Journal articles: 'Laser scannig'

1

Opoka, Szymon, Pawel Malinowski, Tomasz Wandowski, L. Skarbek, and Wieslaw Ostachowicz. "Damage Detection Using Electromechanical Impedance Technique Combined with Scanning Laser Vibrometry." Key Engineering Materials 569-570 (July 2013): 687–94. http://dx.doi.org/10.4028/www.scientific.net/kem.569-570.687.

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The paper consists of two parts. First, Electromechanical Impedance (EMI) method is proven to be able to determine some vibrational characteristics of the investigated structure. In order to verify this statement, Scannig Laser Vibrometry (SLV) is used to correlate frequency peaks of velocity (or displacement) operational deflection shapes with corresponding ones obtained by EMI method. Finally, the influence of moisture content in CFRP sample on resonance peaks is investigated using EMI method. Damage detection indicator in this case is based on shifts of resonant peaks.

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Tirlapur, Uday K., Erhard Kranz, and Mauro Cresti. "Characterisation of isolated egg cells,in vitrofusion products and zygotes ofZea maysL. using the technique of image analysis and confocal laser scanning microscopy." Zygote 3, no. 1 (February 1995): 57–64. http://dx.doi.org/10.1017/s0967199400002380.

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SummaryChanges in membrane Ca2+, calcium receptor protein calmodulin, endoplasmic reticulum (ER), mitochondria and cellulose in unfixed, living, isolated egg cells and fusion products of pairs of one egg and one sperm cell ofZea maysL. have been investigated using chlorotetracycline, fluphenazine, immunocytochemical techniques, 3,3'dihexyloxa-carbocyanine iodide (DiOC6(3)) and calcofluor white in conjuction with computer-controlled video image analysis. In addition, confocal laser scannig microscopy has been used in conjuction with ethidium bromide to detect the nature and location of the sperm cell nuclear chromatin before and after karyogamy. Digitised video images of chlorotetra cycline (CTC) fluorescence reveal that egg cells contain high levels of membrane Ca2+in organelles present around the nucleus while the cytosolic signal is relatively low. Intense CTC fluorescence is invariably present just below the plasma membrane of egg cells and a certain degree of regionalised distribution of Ca2+in cytoplasm is also discrnible. Similarly, the fluphenazine (FPZ)-detectable calmodulin (CaM) and that localised immunocytochemically using monoclonal anti-CaM antibodies reveal high levels of Cam in the vicinity of the nucleus in egg cells. Only a few ER profiles and mitochondria could be visualised in the egg cell and no calcofluor fluorescence could be detected. Followingin vitrofertilisation of single isolated eggs substantial changes in the Ca2+levels occur which include an increase in the membrane Ca2+of the fusion product, particularly in the cytosol and around the nucleus. Unlike in the eggs the fine CTC fluorescence signal below the plasma membrane is not detectable in the fusion products. Compared with isolated egg cell protolasts an increase in the CaM level in the cytoplasm was observed in the fusion products. There is a slight increase in the CaM level in the cytoplasm was observed in the fusion products. There is a slight increase in the fluorescene around the fusion product is visible after 16 h in in culture. The sperm cell chromatin in the fusion product is highly condensed, unlike that of the egg cell, and confocally imaged serial optical sections of thein vitrofusion product reveal the occurrence of karyogamy 35 min following gamete fusion. First visual evidence for intermingling of sperm nuclear chromatin in the zygotic nuclei is also provided.

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Kim, Cheol Hee, Won Ho Choi, and Ki Young Park. "Application of Laser Remote Welding to an Aluminum Automotive Part." Materials Science Forum 654-656 (June 2010): 966–69. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.966.

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Aluminum alloys are extensively used in the automotive industry in response to increasing requirements for weight reduction in car body architecture. Laser welding of Al alloys has many advantages such as low heat input, narrow heat affected zone, minimal thermal distortion and flexibility. Recently, the development of high brightness lasers - thin disk lasers and fiber lasers enable long focal distance welding so that laser remote welding with scanning mirrors can be used in laser welding of Al alloys. In this study, laser remote welding was implemented to a heat shield part of an automobile by utilizing a 4kW disk laser and a 2-axis scanner. By replacing conventional resistance spot welding, the weld flange length could be reduced from 15mm to 8mm and a cycle time for each welding point could also be reduced from 3.5s to 0.6s.

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Jeong, In-Sook, Min-Sung Ban, Kwang-Eun Son, and Byoung-Bag Lee. "Development of Ftheta Lens for Laser Scanning Unit." Transactions of the KSME C: Industrial Technology and Innovation 1, no. 1 (July 1, 2013): 13–19. http://dx.doi.org/10.3795/ksme-c.2013.1.1.013.

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NAP, Mircea Emil, Tudor SĂLĂGEAN, Petre Iuliu DRAGOMIR, and Elemer Emanuel ȘUBA. "Using the Laser Scanning Technology in the Evaluation of a Building Located on Ion Neculce Street from Cluj-Napoca." Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Horticulture 76, no. 2 (November 19, 2019): 221. http://dx.doi.org/10.15835/buasvmcn-hort:2019.0039.

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Laser scanning describes a method by which a surface is sampled or scanned using laser technology. The science of valuation has become more and more sophisticated as the development of society in general and of the economy in particular, in order to meet, eventually, complex information needs. The main idea of this project is to carry out scanning works in the framework of the evaluation report of a property. For this project, The Leica Scanstation C10 laser scanner was used and the following methods were applied for the scan operation: Backward Intersection Method, Deletion Method. For the valuation we used Market approach and Cost approach. The use of the laser scanner led to the expected results, namely the retrieval of an enormous volume of information collected from the field, of extremely high accuracy which subsequently helped to model a large number of details necessary to improve the evaluation process.

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Wang Wei, 王蔚, 沈杰 Shen Jie, 刘伟军 Liu Weijun, 卞宏友 Bian Hongyou, 李强 Li Qiang, and 周瑜 Zhou Yu. "脉冲激光清洗过程中振镜扫描速度对TA15钛合金表面氧化层的影响." Chinese Journal of Lasers 48, no. 18 (2021): 1802004. http://dx.doi.org/10.3788/cjl202148.1802004.

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Lubis, Fadhli Umar. "METODE FADHLI FAME LANER UNTUK ALAT 3D LASER SCANNER." Journal of Mechanical Engineering and Mechatronics 3, no. 1 (January 18, 2019): 21. http://dx.doi.org/10.33021/jmem.v3i1.534.

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The 3D laser scanner that will be used in this study is a design tool for students of the 2007 Mechanical Engineering Department. This tool has been validated and used in several studies. Improvements to the 3D Laser Scanner tool are still being carried out, especially in the accuracy of the geometry of the 3D model produced and the time required in the processing of the scanning data. The research was conducted with the aim to increase the results obtained from the scanning process in order to have maximum results and have a fast processing time. In the research conducted, there are several differences with the previous method, namely the use of Visual Basic, supporting software, placing the camera and laser and camera settings. Based on the results of the study, the final results of the scan show the size of the test object has a smaller deviation of 8.12% for height, 0.8% for width and 19.3% for the neck, compared to previous studies of 61.09% for height, 51.8% for width and 40.75% for neck. For the time of the scanning process, there is a shortening of time that is very far compared to previous research, namely the time needed for 1 minute 56 seconds, while in the previous study it took 1 hour 41 minutes 37 seconds.

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Tan Ge, 谭舸, 花向红 Hua Xianghong, 陶武勇 Tao Wuyong, 赵不钒 Zhao Bufan, and 李丞 Li Cheng. "基于激光跟踪仪的多测站地面激光扫描点云配准方法." Chinese Journal of Lasers 48, no. 17 (2021): 1710002. http://dx.doi.org/10.3788/cjl202148.1710002.

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Wang, Xiao Gang, Xin Zhan Li, and Yue Li. "A Novel Modeling Method Based on Telmat Laser Scanning System." Applied Mechanics and Materials 55-57 (May 2011): 1079–84. http://dx.doi.org/10.4028/www.scientific.net/amm.55-57.1079.

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Though 3D body scanning system is most developed system for achieving body data, there are some scanning dead angles when body is scanned. Based on the scanning file produced by Telmat 3D body scanner, the structure of scanning file was introduced and model algorithm was analyzed. Holes in model were produced because of scanning dead angles, where were on the side of arms, on the side of legs, on the side of upper body, in the side of arms and in the side of legs. A 3D system was developed to automatically read the scanning file and reconstruct body model in it. At the same time holes can be automatic identified and repaired by this system. Then the model repaired was compared to the initial model produced by Telmat system and to confirm the integrality. The algorithm of program is fit to 3D scanning file from all kinds of body scanner system, which holes were produced. The automatic system perfected 3D scanning system and overcome the difficulty produced by the hardware in scanning system.

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Hu, H. C., G. Q. Zhou, X. Zhou, Y. Z. Tan, and J. D. Wei. "DESIGN AND IMPLEMENT OF A CONICAL AIRBORNE LIDAR SCANNING SYSTEM." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-3/W10 (February 8, 2020): 1247–52. http://dx.doi.org/10.5194/isprs-archives-xlii-3-w10-1247-2020.

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Abstract. At present, the main LiDAR is single-point lidar. APD arrays and laser arrays are restricted to exit, so the number of area array LiDAR is scarce. Single-point lidar can't form a scanning pattern with only one laser point on the ground after launching laser, so it must have a set of scanning device for single-point lidar. The scanning device designed in this paper forms a circular scanning area on the ground by rotating the refraction prism, and at the same time forms a conical field of view. At present, marine LiDAR uses this kind of scanner more frequently. The advantages of this scanner are: simple mechanical structure and smooth operation. Overlapping elliptical scanning trajectories can be obtained during flight, which increases scanning density. Ultra-low dispersion glass is used as refractive prism in this paper. In a certain range of laser frequencies, the refractive prism has almost the same effect on laser refraction at different frequencies. The simulation results show that the scanner can be used as a common LiDAR scanner or a dual-frequency LiDAR scanner.

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11

Kim, Kyung Han, Kwang Ho Yoon, Jae Hoon Lee, Jeong Suh, and Jong Soo Kim. "Laser Scanner Stage Synchronization Method for Ultrafast and Wide Area Fabrication." Advanced Materials Research 383-390 (November 2011): 6277–82. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.6277.

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This paper presents an on-the-fly method to synchronize a laser scanner and a linear stage for fast and wide area fabrication. Demands for high-precision laser processing with wide area have been increasing for a number of applications such as in solar cell batteries, display parts, electronic components, and the automobile industry. An ultra high-speed laser scanner system is limited by its size of scanning area, for example, its scanning area is only 50 × 50 mm2. Recently, a laser scanner system that could scan a wide area was developed; however, it was found that the scanning quality of this scanner decreased with an increase in the scanning area. The developed method is different from the existing step and scanning method in that it our method ensures continuous stage movement, which may improve the processing speed and in turn the laser fabrication quality.

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Tkáč, Matúš, and Peter Mesároš. "3D LASER SCANNING OF THE HISTORIC GREEK CATHOLIC CHURCH – CASE STUDY." Czech Journal of Civil Engineering 2, no. 1 (June 30, 2016): 123–28. http://dx.doi.org/10.51704/cjce.2016.vol2.iss1.pp123-128.

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Laser scanning is the most modern technology for high quality focusing on real objects. 3D laser scanning technology allows the space digitizing of objects which means transferring different objects from the real world into a 3D digital environment where they can continue to work. 3D object scanning allows enhancing the design process, speeds up and reduces data collection errors, saves time and money and thus makes it an attractive alternative to traditional data collection techniques. This technology has wide application and it can be used for surveying of various objects such as buildings, factory buildings, machinery, equipment, engineering networks and also cultural monuments or statues. The result of a scan is a 3d model point cloud which represents threedimensional image of scanned objects and complex shapes. The aim of the paper is description of methodology of the work with 3D laser scanner Faro Focus X130 from Faro Company on the real building object - historic greek catholic church. This paper describes the methodology of laser scanning, describes the specific step during scanning and describes the possibility of create 2D documentation from 3D model point clouds.

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13

Heinz, Erik, Markus Mettenleiter, Heiner Kuhlmann, and Christoph Holst. "Strategy for Determining the Stochastic Distance Characteristics of the 2D Laser Scanner Z + F Profiler 9012A with Special Focus on the Close Range." Sensors 18, no. 7 (July 12, 2018): 2253. http://dx.doi.org/10.3390/s18072253.

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Kinematic laser scanning with moving platforms has been used for the acquisition of 3D point clouds of our environment for many years. A main application of these mobile systems is the acquisition of the infrastructure, e.g., the road surface and buildings. Regarding this, the distance between laser scanner and object is often notably shorter than 20 m. In the close range, however, divergent incident laser light can lead to a deterioration of the precision of laser scanner distance measurements. In the light of this, we analyze the distance precision of the 2D laser scanner Z + F Profiler 9012A, purpose-built for kinematic applications, in the range of up to 20 m. In accordance with previous studies, a clear dependency between scan rate, intensity of the backscattered laser light and distance precision is evident, which is used to derive intensity-based stochastic models for the sensor. For this purpose, a new approach for 2D laser scanners is proposed that is based on the static scanning of surfaces with different backscatter. The approach is beneficial because the 2D laser scanner is operated in its normal measurement mode, no sophisticated equipment is required and no model assumptions for the scanned surface are made. The analysis reveals a lower precision in the range below 5 m caused by a decreased intensity. However, the Z + F Profiler 9012A is equipped with a special hardware-based close range optimization partially compensating for this. Our investigations show that this optimization works best at a distance of about 2 m. Although increased noise remains a critical factor in the close range, the derived stochastic models are also valid below 5 m.

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Majid, Z., C. L. Lau, and A. R. Yusoff. "THREE-DIMENSIONAL RECORDING OF BASTION MIDDLEBURG MONUMENT USING TERRESTRIAL LASER SCANNER." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B5 (June 15, 2016): 323–26. http://dx.doi.org/10.5194/isprsarchives-xli-b5-323-2016.

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This paper describes the use of terrestrial laser scanning for the full three-dimensional (3D) recording of historical monument, known as the Bastion Middleburg. The monument is located in Melaka, Malaysia, and was built by the Dutch in 1660. This monument serves as a major hub for the community when conducting commercial activities in estuaries Malacca and the Dutch build this monument as a control tower or fortress. The monument is located on the banks of the Malacca River was built between Stadhuys or better known as the Red House and Mill Quayside. The breakthrough fort on 25 November 2006 was a result of the National Heritage Department through in-depth research on the old map. The recording process begins with the placement of measuring targets at strategic locations around the monument. Spherical target was used in the point cloud data registration. The scanning process is carried out using a laser scanning system known as a terrestrial scanner Leica C10. This monument was scanned at seven scanning stations located surrounding the monument with medium scanning resolution mode. Images of the monument have also been captured using a digital camera that is setup in the scanner. For the purposes of proper registration process, the entire spherical target was scanned separately using a high scanning resolution mode. The point cloud data was pre-processed using Leica Cyclone software. The pre-processing process starting with the registration of seven scan data set through overlapping spherical targets. The post-process involved in the generation of coloured point cloud model of the monument using third-party software. The orthophoto of the monument was also produced. This research shows that the method of laser scanning provides an excellent solution for recording historical monuments with true scale of and texture.

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Majid, Z., C. L. Lau, and A. R. Yusoff. "THREE-DIMENSIONAL RECORDING OF BASTION MIDDLEBURG MONUMENT USING TERRESTRIAL LASER SCANNER." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B5 (June 15, 2016): 323–26. http://dx.doi.org/10.5194/isprs-archives-xli-b5-323-2016.

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This paper describes the use of terrestrial laser scanning for the full three-dimensional (3D) recording of historical monument, known as the Bastion Middleburg. The monument is located in Melaka, Malaysia, and was built by the Dutch in 1660. This monument serves as a major hub for the community when conducting commercial activities in estuaries Malacca and the Dutch build this monument as a control tower or fortress. The monument is located on the banks of the Malacca River was built between Stadhuys or better known as the Red House and Mill Quayside. The breakthrough fort on 25 November 2006 was a result of the National Heritage Department through in-depth research on the old map. The recording process begins with the placement of measuring targets at strategic locations around the monument. Spherical target was used in the point cloud data registration. The scanning process is carried out using a laser scanning system known as a terrestrial scanner Leica C10. This monument was scanned at seven scanning stations located surrounding the monument with medium scanning resolution mode. Images of the monument have also been captured using a digital camera that is setup in the scanner. For the purposes of proper registration process, the entire spherical target was scanned separately using a high scanning resolution mode. The point cloud data was pre-processed using Leica Cyclone software. The pre-processing process starting with the registration of seven scan data set through overlapping spherical targets. The post-process involved in the generation of coloured point cloud model of the monument using third-party software. The orthophoto of the monument was also produced. This research shows that the method of laser scanning provides an excellent solution for recording historical monuments with true scale of and texture.

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Feng Zhu, Feng Zhu, Jianyong Ma Jianyong Ma, Wei Huang Wei Huang, Jin Wang Jin Wang, and Changhe Zhou Changhe Zhou. "Parallel laser writing system with scanning Dammann lithography." Chinese Optics Letters 12, no. 8 (2014): 080501–80504. http://dx.doi.org/10.3788/col201412.080501.

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Hong. "3D Indoor Modeling Based on Terrestrial Laser Scanning." Journal of the Korean Society of Civil Engineers 35, no. 2 (2015): 525. http://dx.doi.org/10.12652/ksce.2015.35.2.0525.

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Song, Dae-Gwon, Jong-Keun Park, Jae-Gyu Kim, Jung-Hyun Park, Sang-Yang So, Yoon-Seok Kwak, Min-Sik Yang, An-Sik Choi, and Tae-Kyung Kim. "8 Beam Laser Diode Development for Laser Scanning Unit." Korean Journal of Optics and Photonics 21, no. 3 (June 25, 2010): 111–17. http://dx.doi.org/10.3807/kjop.2010.21.3.111.

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Park, Yong-Hwa. "Slow scanning electromagnetic scanner for laser display." Journal of Micro/Nanolithography, MEMS, and MOEMS 7, no. 4 (October 1, 2008): 043003. http://dx.doi.org/10.1117/1.3033210.

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Devoino, O. G., V. V. Jarski, and A. P. Pilipchuk. "Simulation of surface hardening using a fiber-optic laser scanning." Proceedings of the National Academy of Sciences of Belarus, Physical-Technical Series 63, no. 4 (January 12, 2019): 435–43. http://dx.doi.org/10.29235/1561-8358-2018-63-4-435-443.

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An analysis of process of scanning laser processing is made. The possibility of use of program and changeable power of a laser radiation in the course of scanning is shown. A mathematical model of process of training is developed by the scanning laser radiation. The model considers parameters of reciprocation of a laser beam and headway of a detail. Calculation of the temperature profile arising at laser training with a constant power and with change of power of a laser radiation depending on the provision of a laser beam at its relative movement is executed. Implementation of laser training with a program and changeable power of radiation in the course of scanning allows lowering a metabolic cost by 25 % with preservation of the given geometry of a zone of hardening. Results of laser training of a surface of steel 45 with the gas laser and the process unit on the basis of the fiberoptic laser with power up to 2 kW are presented. The volume, hardened in unit of time, was taken for an indicator of efficiency. Use of radiation of the fiber-optic laser provides increase in efficiency of training by 3–5 times in comparison with use of radiation of CO2 laser of the same power. The gained effect is explained by change of conditions of interaction of radiation with the surface of metal at change by an order of a radiation wavelength and also by change of balance distribution of heat in a zone of influence of a laser beam. Taking into account higher efficiency of fiber-optic lasers in comparison with gas, the energy efficiency of use of fiber-optic lasers for the surface strengthening is 9–15 times higher than when using CO2lasers.

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Walker, K. P., S. T. Schuschereba, P. R. Edsall, B. E. Stuck, and P. D. Bowman. "Production of a uniform cellular injury by raster scanning of cells for the study of laser bioeffects." American Journal of Physiology-Cell Physiology 292, no. 4 (April 2007): C1536—C1542. http://dx.doi.org/10.1152/ajpcell.00348.2006.

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Efforts to understand laser bioeffects in cells and tissues have been hindered by a nonuniform cellular response of the specimen, resulting in graded biochemical effects. In addition, the small beam diameters of commonly used lasers limit the number of cells expressing a response to numbers inadequate for the study of biochemical effects. For a limited emission power, expansion of the beam diameter reduces the irradiance, thus requiring longer exposure durations to produce a cellular response. Cultured human retinal epithelial cells were exposed as a single spot (“tophat” exposure) from a carbon dioxide (CO2) laser operating at 10.6 μm or scanned with a raster system and compared with thermal injury produced with heated saline for short periods (1–9 s) at relatively high temperature (55–70°C). Cell viability and induction of the 70 kDa heat shock protein were evaluated as indicators of the cellular response. Initial attempts to use a tophat (uniform energy distribution) exposure resulted in a nonuniform cellular response (and nonuniform energy distribution) due to diffraction effects from the 2-mm selection aperture. However, raster scanning for appropriate times with the CO2 laser yielded uniform cell viability and heat shock protein synthesis that were comparable to dipping cells in heated saline. Because scanning results in a homogeneous exposure of cells, the described scanning technique may be applied to studies of cellular responses to other lasers to evaluate photochemical and photomechanical effects.

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Metawie, Mahmoud, and Mohamed Marzouk. "OPTIMIZING LASER SCANNING POSITIONS IN BUILDINGS EXTERIORS: HERITAGE BUILDING APPLICATION." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 26, no. 3 (February 25, 2020): 304–14. http://dx.doi.org/10.3846/jcem.2020.12006.

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Digital documentation for heritage buildings is one of the methods of preserving them as it provides a current record for the buildings. Digital records of heritage buildings can be used for future building rehabilitation, or be presented to the public to raise the awareness, increase tourism and decrease vandalism. This paper focuses on scanning object geometry factor to increase the quality of heritage’s façade point cloud. It optimizes the scanner locations and the scanner field of view to increase the point cloud quality and shorten the scanning time while guaranteeing a set of quality constraints for the point cloud. The quality constraints are based on the incidence angle between the scanned surface and the laser beam, and the max spacing between points. Three different multi-objective optimization algorithms are utilized: 1) genetic algorithm, 2) Jaya algorithm, and 3) particle swarm optimization to increase the quality. Optimization performance measures are adopted to compare the outputs of the optimization algorithms. A multi-criteria decision-making technique (Weighed sum model) is used to choose the optimum solution between the Pareto frontier solutions. Optimization algorithms minimize point cloud density and scanning time while assuring a required point spacing and max incidence angle by changing distance between laser scanner and scanned Facade, horizontal and vertical scan repetitions, and scanner different resolutions. The Jaya algorithm generates the most diversifiable optimal solutions and it is the fastest of the three algorithms considered. This research focuses on vertical building façade and future research will include the all types of Heritage façade. Omar Tosson Palace in Egypt is considered as a case study to demonstrate the use of the developed methodology and to illustrate its essential features.

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Baba, So, Jae Hyuk Park, Harumichi Sato, Shizuka Nakano, Kiwamu Ashida, and Jun Akedo. "Laser-Anneal of Metal-Based Micro Optical Scanner Derived by Aerosol Deposition." Key Engineering Materials 388 (September 2008): 195–98. http://dx.doi.org/10.4028/www.scientific.net/kem.388.195.

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To retain the driving properties of metal-based micro optical scanner derived by aerosol deposition (AD) technique, CO2 laser irradiation was used to anneal the PZT films deposited onto the stainless-steel substrate. Stainless-steel mirror and frame of the scanner with the film annealed by laser irradiation maintained their metallic luster. The scanner with the film annealed by laser irradiation at 600 °C for 1 min has a scanning angle over 30 degree that is comparable with the scanning angle of a similar scanner annealed by electric furnace at 600 °C for 10 min.

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Tanaka, S., K. Hasegawa, N. Okamoto, R. Umegaki, S. Wang, M. Uemura, A. Okamoto, and K. Koyamada. "SEE-THROUGH IMAGING OF LASER-SCANNED 3D CULTURAL HERITAGE OBJECTS BASED ON STOCHASTIC RENDERING OF LARGE-SCALE POINT CLOUDS." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences III-5 (June 6, 2016): 73–80. http://dx.doi.org/10.5194/isprsannals-iii-5-73-2016.

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We propose a method for the precise 3D see-through imaging, or transparent visualization, of the large-scale and complex point clouds acquired via the laser scanning of 3D cultural heritage objects. Our method is based on a stochastic algorithm and directly uses the 3D points, which are acquired using a laser scanner, as the rendering primitives. This method achieves the correct depth feel without requiring depth sorting of the rendering primitives along the line of sight. Eliminating this need allows us to avoid long computation times when creating natural and precise 3D see-through views of laser-scanned cultural heritage objects. The opacity of each laser-scanned object is also flexibly controllable. For a laser-scanned point cloud consisting of more than 107 or 108 3D points, the pre-processing requires only a few minutes, and the rendering can be executed at interactive frame rates. Our method enables the creation of cumulative 3D see-through images of time-series laser-scanned data. It also offers the possibility of fused visualization for observing a laser-scanned object behind a transparent high-quality photographic image placed in the 3D scene. We demonstrate the effectiveness of our method by applying it to festival floats of high cultural value. These festival floats have complex outer and inner 3D structures and are suitable for see-through imaging.

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Tanaka, S., K. Hasegawa, N. Okamoto, R. Umegaki, S. Wang, M. Uemura, A. Okamoto, and K. Koyamada. "SEE-THROUGH IMAGING OF LASER-SCANNED 3D CULTURAL HERITAGE OBJECTS BASED ON STOCHASTIC RENDERING OF LARGE-SCALE POINT CLOUDS." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences III-5 (June 6, 2016): 73–80. http://dx.doi.org/10.5194/isprs-annals-iii-5-73-2016.

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We propose a method for the precise 3D see-through imaging, or transparent visualization, of the large-scale and complex point clouds acquired via the laser scanning of 3D cultural heritage objects. Our method is based on a stochastic algorithm and directly uses the 3D points, which are acquired using a laser scanner, as the rendering primitives. This method achieves the correct depth feel without requiring depth sorting of the rendering primitives along the line of sight. Eliminating this need allows us to avoid long computation times when creating natural and precise 3D see-through views of laser-scanned cultural heritage objects. The opacity of each laser-scanned object is also flexibly controllable. For a laser-scanned point cloud consisting of more than 107 or 108 3D points, the pre-processing requires only a few minutes, and the rendering can be executed at interactive frame rates. Our method enables the creation of cumulative 3D see-through images of time-series laser-scanned data. It also offers the possibility of fused visualization for observing a laser-scanned object behind a transparent high-quality photographic image placed in the 3D scene. We demonstrate the effectiveness of our method by applying it to festival floats of high cultural value. These festival floats have complex outer and inner 3D structures and are suitable for see-through imaging.

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Huang, Jigang, Qin Qin, Jie Wang, and Hui Fang. "Two Dimensional Laser Galvanometer Scanning Technology for Additive Manufacturing." International Journal of Materials, Mechanics and Manufacturing 6, no. 5 (October 2018): 332–36. http://dx.doi.org/10.18178/ijmmm.2018.6.5.402.

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Uhlmann, Eckart, and Alexander Mühlenweg. "Parameterentwicklung im L-PBF-Prozess/Parameter development for laser powder bed fusion." wt Werkstattstechnik online 111, no. 07-08 (2021): 507–12. http://dx.doi.org/10.37544/1436-4980-2021-07-08-39.

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Die aktuelle Literatur zum Thema Laser Powder Bed Fusion (L-PBF) beschäftigt sich größtenteils mit Dauerstrich- (continuous-wave, cw) Laser-Anlagen, die kontinuierlich strahlend das Pulverbett scannen. Zusätzlich gibt es Anlagen mit gepulsten (quasi-continuous-wave, qcw) Lasern, die einen Puls bestimmter Dauer auf einen Punkt abgeben und dann zum nächsten Punkt springen. Die Parametersätze sind nicht ohne Weiteres zwischen den Anlagentypen übertragbar. Diese Arbeit behandelt die Parameterentwicklung für den Werkstoff Haynes 282 auf einer qcw-L-PBF-Anlage.   Current literature on Laser Powder Bed Fusion (L-PBF) mainly focuses on continuous-wave (cw) laser systems to scan the powder bed while continuously emitting laser light. Also, there are systems with pulsed (quasi-continuous-wave, qcw) lasers to scan one point in the powder bed for a set duration and then jump to the next point. The parameter sets for one system are not easy to transfer to a different type of laser system. This work describes the development of a parameter set for Haynes 282 on a system with a qcw laser.

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WIEGER, V., M. STRASSL, and E. WINTNER. "Pico- and microsecond laser ablation of dental restorative materials." Laser and Particle Beams 24, no. 1 (March 2006): 41–45. http://dx.doi.org/10.1017/s0263034606060083.

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For biological hard tissues as well as for artificial restoration materials, ultra-short laser pulses (USLP) have proven their suitability for ablation with negligible collateral damage providing many advantages. For this paper, it was the aim to investigate the suitability of scanned USLP for the ablation of dental restorative materials compared to the microsecond pulses of conventional Erbium lasers. Scanning electron microscopy allowed analyzing the quality of the cavity surfaces with respect to structural properties as well as temperature exposition. Quantitative results about the ablation efficiency are given for different laser parameters on dental hard tissue and a broad variety of dental restoration materials, the latter being reported for the first time.

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Luo, Dong, Si Hai Chen, Wei Chen, Guo Hua Jiao, and Yuan Fu Lu. "Inverse Hysteresis Compensation of One-Dimensional Piezoelectric Scanner with Generalized Prandtl-Ishlinskii Model." Advanced Materials Research 945-949 (June 2014): 1956–61. http://dx.doi.org/10.4028/www.scientific.net/amr.945-949.1956.

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Laser scanner is one of the key components in laser radar, adaptive optics, space optical communications and other fields, which can achieve precise control of the laser beam deflection or scanning. Due to the high precision, high bandwidth and small momentum of inertia, piezoelectric scanner has been widely developed in recent years. It’s necessary to design hysteresis compensation algorithm because the hysteresis effect of piezoelectric ceramics will affect the scanning accuracy of one-dimensional piezoelectric scanner. In the paper, we firstly establish an inverse hysteresis model based on the generalized Prandtl-Ishlinskii model which describes properties of the piezoelectric ceramic, then use particle swarm algorithm to identify the parameters of inverse hysteresis model, obtaining a triangular wave signal with inverse hysteresis to drive one-dimensional piezoelectric scanner. Experimental results show that the scanning nonlinearity is improved from 3.5% to less than 1% after driven by triangular wave votlage within 50Hz, the scanning accuracy of one-dimensional piezoelectric scanner is improved effectively.

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Shaheen, Mohamed E., Joel E. Gagnon, and Brian J. Fryer. "Scanning electron microscope studies on laser ablation of solids." Laser and Particle Beams 37, no. 01 (March 2019): 101–9. http://dx.doi.org/10.1017/s0263034619000132.

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AbstractThis study investigates the interaction of picosecond laser pulses with sapphire and brass in air using scanning electron microscopy. A picosecond laser system operating at a wavelength of 785 nm, pulse width of 110 ps, and variable repetition rate (1–1000 Hz) was used in this study. The pulse width applied in this work was not widely investigated as it lies in the gap between ultrashort (femtosecond) and long (nanosecond) pulse width lasers. Different surface morphologies were identified using secondary electron and backscattered electron imaging of the ablated material. Thermal ablation effects were more dominant in brass than in sapphire. Exfoliation and fractures of sapphire were observed at high laser fluence. Compared with brass, multiple laser pulses were necessary to initiate ablation in sapphire due to its poor absorption to the incident laser wavelength. Ablation rate of sapphire was lower than that of brass due to the dissipation of a portion of the laser energy due to heating and fracturing of the surface.

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Nguyen, Huu-Cuong, and Byung-Ryong Lee. "3D Model Reconstruction System Development Based on Laser-Vision Technology." International Journal of Automation Technology 10, no. 5 (September 5, 2016): 813–20. http://dx.doi.org/10.20965/ijat.2016.p0813.

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We propose a three-dimensional (3D) scanning system based on laser-vision technique and rotary mechanism combination for automatic 3D model reconstruction. The proposed scanning system consists of a laser projector, camera, and turntable. For laser-camera calibration, a new and simple method is applied. The 3D point cloud data of the surface of the scanned object are fully collected by integrating the extracted laser profiles from the laser stripe images corresponding to the rotary angles of the rotary mechanism. The obscured laser profile problem is solved by an additional camera at another viewpoint. From the collected 3D point cloud data, the 3D model of the scanned object is reconstructed based on the facet-representation method. The reconstructed 3D models showed the effectiveness and applicability of the proposed 3D scanning system in many 3D model-based applications.

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Costantino, Domenica, Massimiliano Pepe, and Maria Giuseppa Angelini. "EVALUATION OF REFLECTANCE FOR BUILDING MATERIALS CLASSIFICATION WITH TERRESTRIAL LASER SCANNER RADIATION." Acta Polytechnica 61, no. 1 (March 1, 2021): 174–98. http://dx.doi.org/10.14311/ap.2021.61.0174.

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The main purpose of this work is the evaluation of the potential of Terrestrial Laser Scanning (TLS) technology to perform a reflectance analysis of scanned objects. A laser beam, having a coherent beam in the field of visible light (wavelength between 532nm and 680 nm), can lead to optical diffraction phenomena that allow a correlation between the degree of crystallinity of solids (in particular dispersed crystalline materials) and its reflectivity. Different materials with known crystallinity values have been examined and the diffraction value has been analysed for two types of lasers, one pulsed and the other phase measurement, with two different acquisition conditions (nadiral and oblique position). The results demonstrated the correlation by verifying that the incident laser light beam is more refracted by materials with a higher degree of crystallinity than less crystalline or amorphous materials.

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Saraswat, Manisha, Samantha M. Hamilton, Nicole Jaremco, Howard Gibbins, Clive Coy, and Phil Currie. "Piecing Together Prehistoric Life: Scanning and Articulating Gorgosaurus." Alberta Academic Review 2, no. 2 (September 21, 2019): 65–66. http://dx.doi.org/10.29173/aar68.

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The Skull bones of a Gorgosaurus Libratus was laser scanned in order to articulate the model into software and 3D print. The model had to be articulated due to some missing bone, making it unrealistic to put together. Using the scanned pieces we articulated the model making a skull of The Gorgosaurus Libratus. This detailed computer skull can be sent anywhere in the world, for anyone to study. These scans could also be used to find out how the Gorgosaurus Libratus bit down or determine the way these animals moved. Prior to laser scanning, a method known as Photogrammetry was used. This method involves taking photos of the model and processing the images on a computer, which slow down the process. Another way used to replicate bones was by making silicone molds. This could damage the bone which makes it a method used less often. Laser scanning is the fastest and safest method in order to scan a bone. After the bones were articulated on the computer they were sent to a 3D printer. Unfortunately, the printer beds could not hold the massive skull. Due to this, the bones were printed half size. In order to 3D print, the holes of the model had to be filled using another program. The holes were caused by the light of the laser scanner not being able to go into all the holes creating shadows that the laser scanner could not pick up. However, after the holes were filled some of the objects were still too big to fit on the printer bed. Therefore, some of the objects were cut in half to fit. The 3D printed models were then printed and assembled.

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Kurkela, Matti, Mikko Maksimainen, Arttu Julin, Toni Rantanen, Juho-Pekka Virtanen, Juha Hyyppä, Matti Tapio Vaaja, and Hannu Hyyppä. "Utilizing a Terrestrial Laser Scanner for 3D Luminance Measurement of Indoor Environments." Journal of Imaging 7, no. 5 (May 10, 2021): 85. http://dx.doi.org/10.3390/jimaging7050085.

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We aim to present a method to measure 3D luminance point clouds by applying the integrated high dynamic range (HDR) panoramic camera system of a terrestrial laser scanning (TLS) instrument for performing luminance measurements simultaneously with laser scanning. We present the luminance calibration of a laser scanner and assess the accuracy, color measurement properties, and dynamic range of luminance measurement achieved in the laboratory environment. In addition, we demonstrate the 3D luminance measuring process through a case study with a luminance-calibrated laser scanner. The presented method can be utilized directly as the luminance data source. A terrestrial laser scanner can be prepared, characterized, and calibrated to apply it to the simultaneous measurement of both geometry and luminance. We discuss the state and limitations of contemporary TLS technology for luminance measuring.

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Liang, Yubin, Yan Qiu, and Tiejun Cui. "PERSPECTIVE INTENSITY IMAGES FOR CO-REGISTRATION OF TERRESTRIAL LASER SCANNER AND DIGITAL CAMERA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B3 (June 9, 2016): 295–300. http://dx.doi.org/10.5194/isprsarchives-xli-b3-295-2016.

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Co-registration of terrestrial laser scanner and digital camera has been an important topic of research, since reconstruction of visually appealing and measurable models of the scanned objects can be achieved by using both point clouds and digital images. This paper presents an approach for co-registration of terrestrial laser scanner and digital camera. A perspective intensity image of the point cloud is firstly generated by using the collinearity equation. Then corner points are extracted from the generated perspective intensity image and the camera image. The fundamental matrix F is then estimated using several interactively selected tie points and used to obtain more matches with RANSAC. The 3D coordinates of all the matched tie points are directly obtained or estimated using the least squares method. The robustness and effectiveness of the presented methodology is demonstrated by the experimental results. Methods presented in this work may also be used for automatic registration of terrestrial laser scanning point clouds.

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Liang, Yubin, Yan Qiu, and Tiejun Cui. "PERSPECTIVE INTENSITY IMAGES FOR CO-REGISTRATION OF TERRESTRIAL LASER SCANNER AND DIGITAL CAMERA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B3 (June 9, 2016): 295–300. http://dx.doi.org/10.5194/isprs-archives-xli-b3-295-2016.

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Co-registration of terrestrial laser scanner and digital camera has been an important topic of research, since reconstruction of visually appealing and measurable models of the scanned objects can be achieved by using both point clouds and digital images. This paper presents an approach for co-registration of terrestrial laser scanner and digital camera. A perspective intensity image of the point cloud is firstly generated by using the collinearity equation. Then corner points are extracted from the generated perspective intensity image and the camera image. The fundamental matrix F is then estimated using several interactively selected tie points and used to obtain more matches with RANSAC. The 3D coordinates of all the matched tie points are directly obtained or estimated using the least squares method. The robustness and effectiveness of the presented methodology is demonstrated by the experimental results. Methods presented in this work may also be used for automatic registration of terrestrial laser scanning point clouds.

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Che Ku Abdullah, C. K. A. F., N. Z. S. Baharuddin, M. F. M. Ariff, Z. Majid, C. L. Lau, A. R. Yusoff, K. M. Idris, and A. Aspuri. "INTEGRATION OF POINT CLOUDS DATASET FROM DIFFERENT SENSORS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W3 (February 23, 2017): 9–15. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w3-9-2017.

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Laser Scanner technology become an option in the process of collecting data nowadays. It is composed of Airborne Laser Scanner (ALS) and Terrestrial Laser Scanner (TLS). ALS like Phoenix AL3-32 can provide accurate information from the viewpoint of rooftop while TLS as Leica C10 can provide complete data for building facade. However if both are integrated, it is able to produce more accurate data. The focus of this study is to integrate both types of data acquisition of ALS and TLS and determine the accuracy of the data obtained. The final results acquired will be used to generate models of three-dimensional (3D) buildings. The scope of this study is focusing on data acquisition of UTM Eco-home through laser scanning methods such as ALS which scanning on the roof and the TLS which scanning on building façade. Both device is used to ensure that no part of the building that are not scanned. In data integration process, both are registered by the selected points among the manmade features which are clearly visible in Cyclone 7.3 software. The accuracy of integrated data is determined based on the accuracy assessment which is carried out using man-made registration methods. The result of integration process can achieve below 0.04m. This integrated data then are used to generate a 3D model of UTM Eco-home building using SketchUp software. In conclusion, the combination of the data acquisition integration between ALS and TLS would produce the accurate integrated data and able to use for generate a 3D model of UTM eco-home. For visualization purposes, the 3D building model which generated is prepared in Level of Detail 3 (LOD3) which recommended by City Geographic Mark-Up Language (CityGML).

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Kumar, G. Anil, Maneesha Das, Sindhu Ramesh, and Surendranath Garapati. "An in vitro Evaluation of Microtensile Bond Strength of Resin-based Sealer with Dentin Treated with Diode and Nd:YAG Laser." Journal of Contemporary Dental Practice 14, no. 2 (2013): 183–87. http://dx.doi.org/10.5005/jp-journals-10024-1297.

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ABSTRACT Background Smear layer is a negative factor which prevents adhesion of the filling material to the dentinal walls. Recent advances in dental research have incorporated lasers as a potential adjunct in root canal treatment by removing the smear layer before filling the root canal system, enhancing the adhesion of sealers to dentin and improving the sealing ability. Aim To evaluate the microtensile bond strength of AH-Plus resin-based sealer to dentin after treatment with 980 nm diode and 1,064 nm neodymium-doped:yttrium aluminum garnet (Nd:YAG) laser in vitro. Materials and methods Thirty specimens prepared for three groups namely group I (control), group II (980 nm diode–lased specimens) and group III (Nd:YAG–lased specimens). One tooth from each group was observed under scanning electron microscope for evaluation of intracanal root dentin morphology. Remaining specimens were used for making microsections by hard tissue microtome. Specimens for groups II and III were lased with 980 nm diode and 1,064 nm Nd:YAG laser. AH Plus sealer was applied onto specimens and mounted onto Instron universal testing machine for microtensile bond strength testing. Results were subjected to statistical analysis using one-way analysis of variance (ANOVA) and Tukey's test. Results Group III Nd:YAG had maximum mean microtensile bond strength values (11.558 ± 0.869), followed by group II diode (9.073 ± 0.468) and group I control (6.05 ± 0.036). Statistically significant differences were seen among all the groups. SEM analysis shows removal of smear layer in both groups II and III. Conclusion Both Nd:YAG and diode laser were more effective than control group in improving the microtensile bond strength of AH Plus sealer to dentin. Clinical significance Lasers have the potential to increase the adhesiveness of root canal sealer to dentin surface, thereby improving the quality of root canal obturation. How to cite this article Maneesha D, Anil KG, Sindhu R, Surendranath G, Deepak S. An in vitro Evaluation of Microtensile Bond Strength of Resin-based Sealer with Dentin Treated with Diode and Nd:YAG Laser. J Contemp Dent Pract 2013;14(2): 183-187.

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Li, Qinghua, Yuchi Ma, John Anderson, James Curry, and Jie Shan. "Towards Uniform Point Density: Evaluation of an Adaptive Terrestrial Laser Scanner." Remote Sensing 11, no. 7 (April 11, 2019): 880. http://dx.doi.org/10.3390/rs11070880.

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One of the intrinsic properties of conventional terrestrial laser scanning technology is the unevenness of its point density over the scene where objects rendered closer to the scanner are more densely covered than the ones far away. This uneven distribution can be amplified as the working range of a laser scanner gets longer. In such case a higher pulse repetition rate (PRR) is applied to the whole scanning area and the scanning time will be dramatically increased. To improve the efficiency of the conventional laser scanning technology, a prototype of adaptive scanning technology, the HRS3D-AS scanner has been developed by Blackmore Sensors and Analytics, Inc. This paper briefly describes the working principles of the adaptive scanner and presents a thorough evaluation on the distributions of the point density in comparison to the conventional scanning. Based on this study, we show that such a new technology can produce a point cloud of more uniform density and less data volume. The overall field scanning time can be reduced by several times compared to the conventional, PRR-fixed scanning. Such properties are expected to significantly simplify the algorithmic development and increase the productivity in data acquisition and processing. The limitations of this new adaptive scanning technology are also discussed in terms of redundant and unresolved details. Finally, recommendations related to the practicing of such adaptive scan are discussed.

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Yimei Huang, Yimei Huang, Hongqin Yang Hongqin Yang, Xiuqiu Shen Xiuqiu Shen, Yuhua Wang Yuhua Wang, Liqin Zheng Liqin Zheng, Hui Li Hui Li, and Shusen Xie Shusen Xie. "Visualizing NO in live cells by confocal laser scanning microscopy." Chinese Optics Letters 10, s1 (2012): S11701–311703. http://dx.doi.org/10.3788/col201210.s11701.

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Lee, J. D., K. J. Bhang, and W. Schuhr. "3D TEXTURED MODELLING OF BOTH EXTERIOR AND INTERIOR OF KOREAN STYLED ARCHITECTURES." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W5 (August 18, 2017): 439–42. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w5-439-2017.

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This paper describes 3D modelling procedure of two Korean styled architectures which were performed through a series of processing from data acquired with the terrestrial laser scanner. These two case projects illustate the use of terrestrial laser scanner as a digital documentation tool for management, conservation and restoration of the cultural assets. We showed an approach to automate reconstruction of both the outside and inside models of a building from laser scanning data. Laser scanning technology is much more efficient than existing photogrammetry in measuring shape and constructing spatial database for preservation and restoration of cultural assets as well as for deformation monitoring and safety diagnosis of structures.

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Ohno, Kenta, Hiroaki Date, and Satoshi Kanai. "Study on Real-Time Point Cloud Superimposition on Camera Image to Assist Environmental Three-Dimensional Laser Scanning." International Journal of Automation Technology 15, no. 3 (May 5, 2021): 324–33. http://dx.doi.org/10.20965/ijat.2021.p0324.

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Recently, three-dimensional (3D) laser scanning technology using terrestrial laser scanner (TLS) has been widely used in the fields of plant manufacturing, civil engineering and construction, and surveying. It is desirable for the operator to be able to immediately and intuitively confirm the scanned point cloud to reduce unscanned regions and acquire scanned point clouds of high quality. Therefore, in this study, we developed a method to superimpose the point cloud on the actual environment to assist environmental 3D laser measurements, allowing the operator to check the scanned point cloud or unscanned regions in real time using the camera image. The method included extracting the correspondences of the camera image and the image generated by point clouds by considering unscanned regions, estimating the camera position and attitude in the point cloud by sampling correspondence points, and superimposing the scanned point cloud and unscanned regions on the camera image. When the proposed method was applied to two types of environments, that is, a boiler room and university office, the estimated camera image had a mean position error of approximately 150 mm and mean attitude error of approximately 1°, while the scanned point cloud and unscanned regions were superimposed on the camera image on a tablet PC at a rate of approximately 1 fps.

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Hollaus, M., W. Wagner, and K. Kraus. "Airborne laser scanning and usefulness for hydrological models." Advances in Geosciences 5 (December 16, 2005): 57–63. http://dx.doi.org/10.5194/adgeo-5-57-2005.

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Abstract. Digital terrain models form the basis for distributed hydrologic models as well as for two-dimensional hydraulic river flood models. The technique used for generating high accuracy digital terrain models has shifted from stereoscopic aerial-photography to airborne laser scanning during the last years. Since the disastrous floods 2002 in Austria, large airborne laser-scanning flight campaigns have been carried out for several river basins. Additionally to the topographic information, laser scanner data offer also the possibility to estimate object heights (vegetation, buildings). Detailed land cover maps can be derived in conjunction with the complementary information provided by high-resolution colour-infrared orthophotos. As already shown in several studies, the potential of airborne laser scanning to provide data for hydrologic/hydraulic applications is high. These studies were mostly constraint to small test sites. To overcome this spatial limitation, the current paper summarises the experiences to process airborne laser scanner data for large mountainous regions, thereby demonstrating the applicability of this technique in real-world hydrological applications.

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Holmgren, Douglas E., and Warren Robinett. "Scanned Laser Displays for Virtual Reality:A Feasibility Study." Presence: Teleoperators and Virtual Environments 2, no. 3 (January 1993): 171–84. http://dx.doi.org/10.1162/pres.1993.2.3.171.

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Technologies applicable toward a display system in which a laser is raster scanned on the viewer's retina are reviewed. The properties of laser beam propagation and the inherent resolution of a laser scanning system are discussed. Scanning techniques employing rotating mirrors, galvanometer scanners, acoustooptic deflectors, and piezoelectric deflectors are described. Resolution, speed, deflection range, and physical size are strongly coupled properties of these technologies. A radiometric analysis indicates that eye safety would not be a problem in a retina-scanning system. For head-mounted display applications, a monochromatic system employing a laser diode source with acoustooptic and galvanometer scanners is deemed most practical at the present time. A resolution of 1000 × 1000 pixels at 60 frames per second should be possible with such a monochromatic system using currently available off-the-shelf components. A full-color scanned-laser display suitable for head-mounted display use is not judged feasible to build at this time with off-the-shelf components.

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Yu, Qi Wei, Dong Yun Wang, Yu Fang, and Yan Zhu. "Research on the Trajectory Control Method for Laser Marking." Key Engineering Materials 579-580 (September 2013): 614–17. http://dx.doi.org/10.4028/www.scientific.net/kem.579-580.614.

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Laser marking has become one of the most important identification methods. Compared with the dots scanning marking method, vector scanning marking has a faster marking speed due to its less strokes and smooth trajectory. Based on the principle of the laser galvanometer scanning, an information processing method obtaining the vectors information, pre-marking until control the lasers trajectory is putting forward herein. Experiments proved that this information process method could be applied to character, barcode and any other graphs which could be described by vector information.

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Azarov, B. F. "EXPERIENCE OF USING GLS-1500 SCANNER IN ENGINEERING-GEODETIC SURVEYING OF ROADS." Engineering survey 13, no. 2 (September 4, 2019): 26–34. http://dx.doi.org/10.25296/1997-8650-2019-13-2-26-34.

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Abstract: modern geodetic technologies allow us to quickly obtain relevant, precise and reliable geospatial data. An example of such a technology is ground-based laser scanning. Currently, this technology is actively used in the performance of engineering and geodetic surveys of roads. The devices and software of different companies are used, differing in their accuracy characteristics and functionality. The article focuses on the experience of the use of GLS-1500 ground-based laser scanner produced by TOPCON and ScanMaster ground-based laser scanning data processing software for engineering and geodetic surveys in order to repair nine sections of the Federal highway R-256 "Chuysky tract" with a total length of over than 100 km. The article also describes the options used for registration of scanning data, the features of their use depending on the availability of geodetic control on the object. The order of processing the results of ground-based laser scanning using ScanMaster software is considered. According to the results of field work on ground-based laser scanning of nine sections of the R-256 highway, the time and accuracy of scanning data were estimated. The method of estimation of time spent on scanning works is also described. The issue of evaluating the accuracy of obtaining the scan data in the ScanMaster software is considered. It is noted that the accuracy of the geodetic reference, thus, the accuracy of the absolute orientation of the scans can be estimated by the differences between the coordinates of the marks that were scanned from the location of the device and calculated by ScanMaster software, and their specified values obtained from the equalization of the geodetic control. In conclusion, it is stated that the optimal time and accuracy of scanning with GLS-1500 device are achieved by using the geodetic reference of the scans by the inverse length-angle intersection at two points of the geodetic control.

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Mezei, Adrián, and Tibor Kovács. "Curvature Adaptive 3D Scanning Transformation Calculation." Periodica Polytechnica Electrical Engineering and Computer Science 62, no. 4 (June 13, 2018): 107–16. http://dx.doi.org/10.3311/ppee.11540.

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Three-dimensional objects can be scanned by 3D laser scanners that use active triangulation. These scanners create three-dimensional point clouds from the scanned objects. The laser line is identified in the images, which are captured at given transformations by the camera, and the point cloud can be calculated from these. The hardest challenge is to construct these transformations so that most of the surface can be captured. The result of a scanning may have missing parts because either not the best transformations were used or because some parts of the object cannot be scanned. Based on the results of the previous scans, a better transformation plan can be created, with which the next scan can be performed. In this paper, a method is proposed for transforming a special 3D scanner into a position from where the scanned point can be seen from an ideal angle. A method is described for estimating this transformation in real-time, so these can be calculated for every point of a previous scan to set up a next improved scan.

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Toś, Cezary. "The Possibilities of Using the Terrestrial Scanning Data for Classification of Rocks in Limestone Mine “Czatkowice”." Reports on Geodesy and Geoinformatics 97, no. 1 (February 3, 2015): 80–90. http://dx.doi.org/10.2478/rgg-2014-0013.

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AbstractThis paper presents results of a research of potential utilisation of the intensity of laser beam reflection recorded by ground-based lasers, for an initial classification of rock formations within the Czatkowice Limestone Quarry. As part of the research, spectrometric analysis in visible (VIS), near-infrared (NIR) and Short-wavelength infrared (SWIR) bands was carried out for rock samples typical for the Czatkowice Quarry. Moreover, the rock samples were scanned using equipment working within different wavelengths. The reflected intensity of the laser beam recorded for each rock sample with several different scanners were analysed to assess their potential use for rock classification. The results of this analysis were then compared with spectral curves of each sample. The relationship between the intensity of the laser beam reflection and the spectral curves can be used for selection of most suitable scanner for rock classification.

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Yan, Heng Feng, Jun Shao, and Ji Min Chen. "Design and Implementation of Machine Vision Automatic Laser Scanning System." Advanced Materials Research 201-203 (February 2011): 940–43. http://dx.doi.org/10.4028/www.scientific.net/amr.201-203.940.

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This paper introduces a solution for laser scanning system, which utilizes machine vision technology. It includes algorithm for positioning and matrix for scanning control. The system can be used to detect an object and laser mark on specific position. This work explains how to use one CCD to catch an object’s position variation relative to a reference point, and how to translate the different coordination systems for laser scanner etc.

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M. Al-Bdairy, Ali, Ahmed A. A. Al-Duroobi, and Maan A. Tawfiq. "POINTS CLOUD PRE-PROCESSING AND SAMPLING BASED ON DISTANCE ALGORITHM TECHNIQUE." Journal of Engineering and Sustainable Development 25, no. 02 (March 1, 2021): 1–8. http://dx.doi.org/10.31272/jeasd.25.2.1.

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Although the rapid development of reverse engineering techniques such as a modern 3D laser scanners, but can’t use this techniques immediately to generate a perfect surface model for the scanned parts, due to the huge data, the noisy data which associated to the scanning process, and the accuracy limitation of some scanning devices, so, the present paper present a points cloud pre-processing and sampling algorithms have been proposed based on distance calculations and statistical considerations to simplify the row points cloud which obtained using MATTER and FORM 3D laser scanner as a manner to obtain the required geometrical features and mathematical representation from the row points cloud of the scanned object through detection, isolating, and deleting the noised points. A MATLAB program has been constructed for executing the proposed algorithms implemented using a suggested case study with non-uniform shape. The results were proved the validity of the introduced distance algorithms for pre-processing and sampling process where the proficiency percent for pre-processing was (18.65%) with a single attempt, and the counted deviation value rang with the sampling process was (0.0002-0.3497mm).

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Journal articles on the topic 'Laser scannig'

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