Relevant bibliographies by topics / Lens

Academic literature on the topic 'Lens'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 March 2023

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Journal articles on the topic "Lens"

1

Kurosaka, Daijiro, Toshiyasu Imaizumi, and Junya Kizawa. "Time Course of Lens Epithelial Cell Behavior in Rabbit Eyes following Lens Extraction and Implantation of Intraocular Lens." Journal of Ophthalmology 2021 (January 16, 2021): 1–8. http://dx.doi.org/10.1155/2021/6659838.

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Background. After cataract surgery, some lens epithelial cells (LECs) transdifferentiate into myofibroblast-like cells, which causes fibric posterior capsule opacification (PCO). Residual LECs differentiate into lens fiber cells, forming Elschnig pearls with PCO. This study was carried out to identify the time course of both types of LEC behavior in rabbit eyes following lens extraction and implantation of an intraocular lens (IOL). Methods. Phacoemulsification and implantation of posterior chamber IOLs were performed in rabbit eyes. Following enucleation, immunohistochemical methods were used to detect α-smooth muscle actin (α-SMA), a marker for myofibroblast-like cells, in the pseudophakic rabbit eyes. A mouse monoclonal antibody against α-SMA was used. Results. Soon after the operation, the LECs migrated and covered the lens capsule. Thereafter, the LECs around the anterior capsular margin were always positive for α-SMA. However, the distributions of these cells were not consistent. In some specimens, α-SMA-positive LECs were present around the IOL optic early after surgery, but most of them had disappeared several weeks after the surgery. The residual cells induced fibrotic PCO. In the other specimens, most LECs around the IOL optic except the anterior capsular margin were negative for α-SMA. In the peripheral region covered by the peripheral anterior and posterior capsules, LECs on the posterior capsule always differentiated into lens fiber cells and formed a Soemmering ring. Thereafter, migration of lens fiber cells from the Soemmering ring and differentiation of LECs in situ on the central posterior capsule consisted of Elschnig pearls type of PCO. Conclusions. Although postoperative LEC behavior is not consistent, residual α-SMA-positive LECs induced fibrotic PCO. The lens fiber cells that migrated from the peripheral capsular bag or that were differentiated in situ covered the central posterior capsule, forming Elschnig pearls with PCO.
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Novo, Samuel G., Adam P. Faranda, Mahbubul H. Shihan, Yan Wang, Ananya Garg, and Melinda K. Duncan. "The Immediate Early Response of Lens Epithelial Cells to Lens Injury." Cells 11, no. 21 (November 1, 2022): 3456. http://dx.doi.org/10.3390/cells11213456.

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Cataracts are treated by lens fiber cell removal followed by intraocular lens (IOL) implantation into the lens capsule. While effective, this procedure leaves behind numerous lens epithelial cells (LECs) which undergo a wound healing response that frequently leads to posterior capsular opacification (PCO). In order to elucidate the acute response of LECs to lens fiber cell removal which models cataract surgery (post cataract surgery, PCS), RNA-seq was conducted on LECs derived from wild type mice at 0 and 6 h PCS. This analysis found that LECs upregulate the expression of numerous proinflammatory cytokines and profibrotic regulators by 6 h PCS suggesting rapid priming of pathways leading to inflammation and fibrosis PCS. LECs also highly upregulate the expression of numerous immediate early transcription factors (IETFs) by 6 h PCS and immunolocalization found elevated levels of these proteins by 3 h PCS, and this was preceded by the phosphorylation of ERK1/2 in injured LECs. Egr1 and FosB were among the highest expressed of these factors and qRT-PCR revealed that they also upregulate in explanted mouse lens epithelia suggesting potential roles in the LEC injury response. Analysis of lenses lacking either Egr1 or FosB revealed that both genes may regulate a portion of the acute LEC injury response, although neither gene was essential for expression of either proinflammatory or fibrotic markers at later times PCS suggesting that IETFs may work in concert to mediate the LEC injury response following cataract surgery.
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Taqwim, Moh Ahsanit, Imam Sucahyo, and Meta Yantidewi. "RANCANG BANGUN ALAT PENENTU PANJANG FOKUS PADA LENSA BIKONVEKS MENGGUNAKAN SENSOR TEMT6000 DAN MOTOR STEPPER." Inovasi Fisika Indonesia 10, no. 2 (July 5, 2021): 81–86. http://dx.doi.org/10.26740/ifi.v10n2.p81-86.

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Abstrak Penelitian ini bertujuan untuk merancang instrumen pengukuran panjang fokus lensa bikonveks secara otomatis. Dengan menerapkan sifat lensa bikonveks dimana berkas-berkas sinar yang paralel terhadap sumbu lensa akan dibiaskan dan berpotongan pada titik fokus. Titik fokus lensa ditentukan menggunakan sensor TEMT6000 dan panjang fokusnya diukur meggunakan motor stepper. Sinar dari dua buah laser dioda yang dipasang sejajar terhadap sumbu lensa akan berpotongan pada titik fokus sehingga intensitas di titik tersebut akan maksimum. Sensor TEMT6000 yang terhubung dengan motor stepper bergerak linier sesumbu dengan sumbu lensa dan berhenti pada titik fokus lensa karena hasil pembacaan sensor bernilai maksimum pada titik tersebut. Mikrokontroler akan menghitung jarak yang ditempuh sensor dan menampilkannya pada display sebagai panjang fokus lensa. Instrumen ini akan diujicobakan pada tiga buah lensa yang memiliki spesifikasi panjang fokus 100 mm, 150 mm, 200 mm, 250 mm dan 300 mm. Berdasarkan penelitian yang dilakukan, panjang fokus hasil pengukuran secara otomatis adalah: 103,8 mm untuk lensa berspesifikasi panjang fokus 100 mm dengan tingkat kesalahan 3,8%, 153,1 mm untuk lensa berspesifikasi panjang fokus 150 mm dengan tingkat kesalahan 2,1%, 203,2 mm untuk lensa berspesifikasi panjang fokus 200 mm dengan tingkat kesalahan 1,6%, 253,2 mm untuk lensa berspesifikasi panjang fokus 250 mm dengan tingkat kesalahan 1,3%, 303,5 mm untuk lensa berspesifikasi panjang fokus 300 mm dengan tingkat kesalahan 1,1%. Penyebab terjadinya penyimpangan titik fokus adalah berkas sinar yang berasal dari laser tidak sejajar dengan sumbu lensa dikarenakan terjadi penyimpangan sudut tembak laser. Kata Kunci: panjang fokus lensa bikonveks, sensor TEMT6000, motor stepper Abstract This study aims to design an automatic instrument for measuring the focal length of biconvex lens. By applying the property of a biconvex lens, the rays parralel to the axis of the lens will be refracted and intersect at the focal point. The focal point of the lens was determined using a TEMT6000 sensor and the focal length measured using a stepper motor. The rays from the two laser diodes that were placed parallel to the lens axis would intersect at the focal point so that the intensity at that point would be maximum. TEMT6000 sensor which is connected to the stepper motor moves linearly about the lens axis and stops at the focal point of the lens because the sensor reading is maximum at that point. Microcontroller would calculate the distance travelled by the sensor and show it on the display as the focal length of the lens. The instrument would be tested on five lenses that have focal length specifications of 100 mm, 150 mm, 200 mm, 250 mm and 300 mm. Based on the research wich has been done, focal length of the automatic measurement results is: 103,8 mm for the lens with the specification of focal length 100 mm and the error was 3,8%, 153,1 mm for the lens with the specification of focal length 150 mm and the error percentage is 2,1%, 203,2 mm for the lens with the specification of focal length 200 mm and the error percentage was 1,6%, 253,2 mm for the lens with the specification of focal length 250 mm and the error percentage was 1,3%, 303,5 mm for the lens with the specification of focal length 300 mm and the error percentage was 1,1%. The cause of focal point deviation is, ray from the laser was not parallel to the lens axis due to laser beam angle deviation. Keywords: focal length of biconvex lens, TEMT6000 sensor, stepper motor
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Xiong, Lang, Yan Sun, Jingqi Huang, Pengjuan Ma, Xiaoran Wang, Jiani Wang, Baoxin Chen, et al. "Long Non-Coding RNA H19 Prevents Lens Fibrosis through Maintaining Lens Epithelial Cell Phenotypes." Cells 11, no. 16 (August 17, 2022): 2559. http://dx.doi.org/10.3390/cells11162559.

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The integrity of lens epithelial cells (LECs) lays the foundation for lens function and transparency. By contrast, epithelial-mesenchymal transition (EMT) of LECs leads to lens fibrosis, such as anterior subcapsular cataracts (ASC) and fibrotic forms of posterior capsule opacification (PCO). However, the underlying mechanisms remain unclear. Here, we aimed to explore the role of long non-coding RNA (lncRNA) H19 in regulating TGF-β2-induced EMT during lens fibrosis, revealing a novel lncRNA-based regulatory mechanism. In this work, we identified that lncRNA H19 was highly expressed in LECs, but downregulated by exposure to TGF-β2. In both human lens epithelial explants and SRA01/04 cells, knockdown of H19 aggravated TGF-β2-induced EMT, while overexpressing H19 partially reversed EMT and restored lens epithelial phenotypes. Semi-in vivo whole lens culture and H19 knockout mice demonstrated the indispensable role of H19 in sustaining lens clarity through maintaining LEC features. Bioinformatic analyses further implied a potential H19-centered regulatory mechanism via Smad-dependent pathways, confirmed by in vitro experiments. In conclusion, we uncovered a novel role of H19 in inhibiting TGF-β2-induced EMT of the lens by suppressing Smad-dependent signaling, providing potential therapeutic targets for treating lens fibrosis.
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Yoon, Min-Hwa. "Changes of Refractive Correction Value with Different Age Group: A Case for Myopia Control Lens, Single Vision Lens and Reverse Geometry Contact Lens." Journal of Korean Ophthalmic Optics Society 18, no. 1 (March 31, 2013): 75–84. http://dx.doi.org/10.14479/jkoos.2013.18.1.075.

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Zhang, Junfang, Jiawei Luo, Guowei Zhang, Bai Qin, Xiumei Ren, and Huaijin Guan. "An Ex Vivo Study on Release, Uptake, and miRNA Profile of Exosomes in Rat Lens." Journal of Ophthalmology 2022 (April 21, 2022): 1–7. http://dx.doi.org/10.1155/2022/6706172.

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Purpose. To identify the ability of releasing and uptaking exosomes in rat lens and characterize the exosomal microRNA profile of lens-derived exosomes. Methods. The rat lenses were cultured ex vivo and the medium was collected. The exosomes were isolated from medium and measured in size and concentration by nanoflow cytometry (nFCM) and transmission electron microscopy (TEM) and verified with CD63 and TSG101 by Western blot. The miRNAs in exosomes released from lens epithelial cells (LECs) were sequenced. The plasma exosomes labeled by PKH26 were used to verify the exosomes uptake LECs, and their colocalized fluorescence was imaged by confocal microscopy. Results. LECs released numerous exosomes into the medium through the capsule, which contained abundant miRNAs. The most abundant miRNAs included miR-184, let-7c-5p, let-7a-5p, let-7b-5p, let-7f-5p, miR-125a-5p, miR-204-5p, miR-125b-5p, miR-1b, and miR-23a-3p. The LECs but not the lens fibre cells showed exosome uptake. The LECs uptake more PKH26-labeled exosomes at day 7 than day 3 and day 14. Conclusions. Our results suggested that LECs can release and uptake exosomes through the capsule. Exosomes may be an important way for the lens to communicate among LECs, aqueous humour, vitreous body, and other ocular tissues.
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Syu, Yong-Sin, and Yung-Chun Lee. "Quantitative Evaluation of Light Collimating for Commercial UV-LEDs Based on Analytic Collimating Lens." Applied Sciences 12, no. 2 (January 17, 2022): 911. http://dx.doi.org/10.3390/app12020911.

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This paper proposes a lens design method for effectively collimating the light emitting from a light-emitting diode (LED). This collimating lens contains two aspherical lens surfaces which can be mathematically characterized using a few designing parameters, and hence is called an analytic collimating lens. An optical ray-tracing algorithm has been developed for these analytic collimating lenses to analyze their optical performance and to optimize their designs. Six high-power and commercially available ultraviolet (UV) LEDs are chosen as examples for demonstrating the optimal collimating lens design. For each UV-LED, the corresponding optical collimating lens is determined by inputting the ray data file provided by the manufacture over a finite-size emitting area. The divergent angles of the six UV-LEDs have been successfully collimated to a narrow range in between 1.56° to 2.84° from their original radiation angle around 46° to 120°. Furthermore, the proposed analytical collimating lenses are suitable for mass-production using standard mold injection methods, and hence possess great potentials for industry applications of LEDs.
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Shen, Xinyue, Manhui Zhu, Lihua Kang, Yuanyuan Tu, Lele Li, Rutan Zhang, Bai Qin, Mei Yang, and Huaijin Guan. "Lanosterol Synthase Pathway Alleviates Lens Opacity in Age-Related Cortical Cataract." Journal of Ophthalmology 2018 (July 11, 2018): 1–9. http://dx.doi.org/10.1155/2018/4125893.

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Purpose. Lanosterol synthase (LSS) abnormity contributes to lens opacity in rats, mice, dogs, and human congenital cataract development. This study examined whether LSS pathway has a role in different subtypes of age-related cataract (ARC). Methods. A total of 390 patients with ARC and 88 age-matched non-ARC patients were enrolled in this study. LSS expression was analyzed by western blot and enzyme-linked immunosorbent assay (ELISA). To further examine the function of LSS, we used U18666A, an LSS inhibitor in rat lens culture system. Results. In lens epithelial cells (LECs), LSS expression in LECs increased with opaque degree C II, while it decreased with opaque degree C IV and C V. While in the cortex of age-related cortical cataract (ARCC), LSS expression was negatively related to opaque degree, while lanosterol level was positively correlated to opaque degree. No obvious change in both LSS and lanosterol level was found in either LECs or the cortex of age-related nuclear cataract (ARNC) and age-related posterior subcapsular cataract (ARPSC). In vitro, inhibiting LSS activity induced rat lens opacity and lanosterol effectively delayed the occurrence of lens opacity. Conclusions. This study indicated that LSS and lanosterol were localized in the lens of human ARC, including ARCC, ARNC, and ARPSC. LSS and lanosterol level are only correlated with opaque degree of ARCC. Furthermore, activated LSS pathway in lens is protective for lens transparency in cortical cataract.
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Mukmin, Amrul, Parjiman, and Muhamad Rif’an. "PENGARUH PENGGUNAAN LENSA DIVERGEN SERTA KONVERGEN TERHADAP DAYA KELUARAN PANEL SURYA." Journal of Electrical Vocational Education and Technology 1, no. 2 (March 21, 2020): 44–51. http://dx.doi.org/10.21009/jevet.0012.08.

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ABSTRACT The purpose of this research is to increase the power output of the solar panels and to know the effect on the solar panel after adding a converging lens and a diverging treatment varying distances and angles. The hypothesis of this study is anticipated to the influence of the use of a diverging lens and converges to the power output of solar panels. This study used an experimental method with quantitative approach. The subjects of the study were used that kind of Polycrystalline solar panels. Data analysis technique used is descriptive analysis with data collection techniques are observation laboratory and field observations. The conclusion of this study is to raise the value of the output power on solar panels can use a converging lens. This is evidenced by the results of the testing are the biggest increase in the converging lens use solar panels to power 900 outputs the angle and the distance between the lens and solar panels with a power output of 25 cm measured 56.46 μW. The influence of the use of a converging lens located on the corner of 150 and the distance between the lens and the solar panel 21 cm with an increase of 203.64%. These values occurred as a converging lens can focus the light so that the intensity of the light falling on the solar panels increases. While the greatest influence use of a diverging lens located on the corner of 300 and the distance between the lens and solar panels 1 cm with a decrease of 63.96%. These values occurred as a diverging lens can refract light so that the intensity of the light falling on the solar panel decreases. ABSTRAK Tujuan penelitian ini yaitu untuk meningkatkan daya keluaran pada panel surya dan untuk mengetahui perbedaan pengaruh pada panel surya setelah ditambahkan lensa konvergen serta divergen dengan perlakuan jarak dan sudut yang bervariasi. Hipotesis penelitian ini yaitu diduga adanya pengaruh dari penggunaan lensa divergen dan konvergen terhadap daya keluaran panel surya. Penelitian ini menggunakan metode eksperimen dengan pendekatan kuantitatif. Subyek penelitian yang digunakan yaitu panel surya jenis Polycrystalline. Teknik analisis data yang digunakan yaitu analisis deskriptif dengan teknik pengumpulan data yaitu observasi laboratorium dan observasi lapangan. Kesimpulan dari penelitian ini yaitu Untuk menaikan nilai daya keluaran pada panel surya dapat menggunakan lensa konvergen. Hal ini dibuktikan dengan hasil pengujian terdapat kenaikan terbesar penggunaan lensa konvergen pada panel surya terhadap daya keluaran yaitu sudut 900 dan jarak antara lensa dan panel surya 25 cm dengan daya keluaran yang terukur 56,46 µW.Pengaruh terbesar penggunaan lensa konvergen terdapat pada sudut 150 dan jarak antara lensa dan panel surya 21 cm dengan kenaikan sebesar 203,64%. Nilai tersebut terjadi karena lensa konvergen dapat memusatkan cahaya sehingga intensitas cahaya yang jatuh pada panel surya meningkat. Sedangkan pengaruh terbesar penggunaan lensa divergen terdapat pada sudut 300 dan jarak antara lensa dan panel surya 1 cm dengan penurunan sebesar 63,96%. Nilai tersebut terjadi karena lensa divergen dapat membiaskan cahaya sehingga intensitas cahaya yang jatuh pada panel surya menurun. jatuh pada panel surya menurun.
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Markiewicz, Ewa, Stephen Barnard, Jackie Haines, Margaret Coster, Orry van Geel, Weiju Wu, Shane Richards, et al. "Nonlinear ionizing radiation-induced changes in eye lens cell proliferation, cyclin D1 expression and lens shape." Open Biology 5, no. 4 (April 2015): 150011. http://dx.doi.org/10.1098/rsob.150011.

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Elevated cataract risk after radiation exposure was established soon after the discovery of X-rays in 1895. Today, increased cataract incidence among medical imaging practitioners and after nuclear incidents has highlighted how little is still understood about the biological responses of the lens to low-dose ionizing radiation (IR). Here, we show for the first time that in mice, lens epithelial cells (LECs) in the peripheral region repair DNA double strand breaks (DSB) after exposure to 20 and 100 mGy more slowly compared with circulating blood lymphocytes, as demonstrated by counts of γH2AX foci in cell nuclei. LECs in the central region repaired DSBs faster than either LECs in the lens periphery or lymphocytes. Although DSB markers (γH2AX, 53BP1 and RAD51) in both lens regions showed linear dose responses at the 1 h timepoint, nonlinear responses were observed in lenses for EdU (5-ethynyl-2′-deoxy-uridine) incorporation, cyclin D1 staining and cell density after 24 h at 100 and 250 mGy. After 10 months, the lens aspect ratio was also altered, an indicator of the consequences of the altered cell proliferation and cell density changes. A best-fit model demonstrated a dose-response peak at 500 mGy. These data identify specific nonlinear biological responses to low (less than 1000 mGy) dose IR-induced DNA damage in the lens epithelium.
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Dissertations / Theses on the topic "Lens"

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Yan, Yufeng. "Photographic Fisheye Lens Design for 35mm Format Cameras." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/613395.

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Fisheye lenses refer to ultra-wide angle lenses that have field of view equal or larger than 180 degrees. Such lenses introduce large amount of barrel distortion to capture at least the entire hemisphere in front of the lens. Fisheye lenses were initially designed for scientific use, such as cloud recording and angle measuring, and were widely used for commercial purposes later. The development of photographic fisheye lenses started in 1960s. However, the lack of detailed references on photographic fisheye lens design makes such design challenging. This thesis provides detailed introduction of photographic fisheye lens design for 35mm format DSLR cameras. A discussion on the history of fisheye lenses is provided to describe the development of fisheye lenses. The tangential and sagittal magnifications are mathematically derived for each fisheye lens projection mapping method to show their differences. The special properties and design issues of photographic fisheye lenses are described in detail. Along with each design issue, some solutions suggested by the author are also provided. The performance of the current diagonal fisheye lenses for 35mm DSLR cameras are evaluated in detail. Then a new diagonal fisheye lens designed by the author is presented and compared with the current diagonal fisheye lenses on the market. Finally, a zoom fisheye lens designed for 35mm DSLR cameras is presented and discussed.
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Shepard, III Ralph Hamilton. "Metamaterial Lens Design." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/194734.

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Developments in nanotechnology and material science have produced optical materials with astonishing properties. Theory and experimentation have demonstrated that, among other properties, the law of refraction is reversed at an interface between a naturally occurring material and these so-called metamaterials. As the technology advances metamaterials have the potential to vastly impact the field of optical science.In this study we provide a foundation for future work in the area of geometric optics and lens design with metamaterials. The concept of negative refraction is extended to derive a comprehensive set of first-order imaging principles as well as an exhaustive aberration theory to 4th order. Results demonstrate congruence with the classical theory; however, negative refraction introduces a host of novel properties. In terms of aberration theory, metamaterials present the lens designer with increased flexibility. A singlet can be bent to produce either positive or negative spherical aberration (regardless of its focal length), its contribution to coma can become independent of its conjugate factor, and its field curvature takes on the opposite sign of its focal power. This is shown to be advantageous in some designs such as a finite conjugate relay lens; however, in a wider field of view landscape lens we demonstrate a metamaterial's aberration properties may be detrimental.This study presents the first comprehensive investigation of metamaterial lenses using industry standard lens design software. A formal design study evaluates the performance of doublet and triplet lenses operating at F/5 with a 100 mm focal length, a 20° half field of view, and specific geometric constraints. Computer aided optimization and performance evaluation provide experimental controls to remove designer-induced bias from the results. Positive-index lenses provide benchmarks for comparison to metamaterial systems subjected to identical design constraints. We find that idiosyncrasies in a metamaterial lens' aberration content can be exploited to produce imaging systems that are superior to their conventional counterparts. However, in some circumstances the reduced low-order aberration content in a metamaterial lens reduces the effectiveness of aberration balancing and stop shifting. Through a series of design experiments the relative advantages and challenges of using metamaterials in lens design are revealed.
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Shams-Ul-Bari, Naveed. "Isospectral orbifold lens spaces." Thesis, Loughborough University, 2016. https://dspace.lboro.ac.uk/2134/23981.

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Spectral theory is the study of Mark Kac's famous question [K], "can one hear the shape of a drum?" That is, can we determine the geometrical or topological properties of a manifold by using its Laplace Spectrum? In recent years, the problem has been extended to include the study of Riemannian orbifolds within the same context. In this thesis, on the one hand, we answer Kac's question in the negative for orbifolds that are spherical space forms of dimension higher than eight. On the other hand, for the three-dimensional and four-dimensional cases, we answer Kac's question in the affirmative for orbifold lens spaces, which are spherical space forms with cyclic fundamental groups. We also show that the isotropy types and the topology of the singularities of Riemannian orbifolds are not determined by the Laplace spectrum. This is done in a joint work with E. Stanhope and D. Webb by using P. Berard's generalization of T. Sunada's theorem to obtain isospectral orbifolds. Finally, we construct a technique to get examples of orbifold lens spaces that are not isospectral, but have the same asymptotic expansion of the heat kernel. There are several examples of such pairs in the manifold setting, but to the author's knowledge, the examples developed in this thesis are among the first such examples in the orbifold setting.
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Yuan, Sheng. "Aberrations of Anamorphic Optical Systems." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195267.

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A detailed study of the aberrations of anamorphic optical systems is presented. This study has been developed with a theoretical structure similar to that of rotationally symmetric optical systems (RSOS) and can be considered a generalization.A general method of deriving the monochromatic primary aberration coefficient expressions for any anamorphic system types with double plane symmetry has been provided.The complete monochromatic primary aberration coefficient expressions for cylindrical anamorphic systems, toroidal anamorphic systems and general anamorphic systems with aspheric departure have been presented, in a form similar to the Seidel aberrations of RSOS.Some anamorphic image system design examples are provided that illustrate the use and value of the theory developed.
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Kumar, Bharat. "The Mechanobiology of the Crystalline Lens." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587649113548924.

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Wilson, Cynthia Nicole. "A Fully Customizable Anatomically Correct Model of the Crystalline Lens." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20130.

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The human eye is a complex optical system comprised of many components. The crystalline lens, an optical component with a gradient index (GRIN), is perhaps the least understood as it is situated inside the eye and as a result is difficult to characterize. Its complex nonlinear structure is not easily measured and consequently not easily modeled. Presently several models of the GRIN structure exist describing the average performance of crystalline lenses. These models, however, do not accurately describe the performance of crystalline lenses on an individual basis and a more accurate individual eye model based on anatomical parameters is needed. This thesis proposes an anatomically correct, individually customizable crystalline lens model. This is an important tool and is needed both for research on the optical properties of human eyes and to diagnose and plan the treatment of optically based visual problems, such as refractive surgery planning. The lens model consisted of an interior GRIN with a constant refractive index core. The anterior and posterior surface was described by conic sections. To realize this eye model, the optical and biometric properties of mammalian lenses were measured and the correlation relationships between these measurements were used to simplify the model down to one fitting parameter which controls the shape of the GRIN. Using this data, an anatomically correct individualizable model of the lens was successfully realized with varying parameters unique to each lens. Using this customizable lens model, customizable human eye models based on measurements of the entire human eye can be realized.
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Ollinger, Christoph German Josef. "A waveguide-based lens-less x-ray microscope." Doctoral thesis, [S.l.] : [s.n.], 2006. http://webdoc.sub.gwdg.de/diss/2006/ollinger.

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Sasián, José. "Joseph Petzval lens design approach." SPIE-INT SOC OPTICAL ENGINEERING, 2017. http://hdl.handle.net/10150/627184.

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Gao, Weichuan, and Jose Sasian. "Air lens vs aspheric surface: a lens design case study." SPIE-INT SOC OPTICAL ENGINEERING, 2017. http://hdl.handle.net/10150/627181.

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We discuss the behavior of air lenses in lens design. The structural aberration coefficients of a thin air lens are derived and compared with their glass thin lens counterpart. Examples are provided for a telephoto lens and the Monochromatic Quartet where air lenses or aspheric surfaces are used.
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DePianto, Daryle Joseph. "Studies on lens fiber cell gene expression & lens differentiation /." Connect to Digital dissertations. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.

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Books on the topic "Lens"

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Contact lens optics and lens design. 2nd ed. Oxford: Butterworth-Heinemann, 1995.

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Contact lens optics and lens design. 3rd ed. Edinburgh: Elsevier Butterworth-Heinemann, 2006.

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Lens design. 4th ed. Boca Raton, FL: CRC Press, 2007.

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Laikin, Milton. Lens design. New York: M. Dekker, 1991.

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Sargeant, Jack. Naked lens. London: Creation Books, 1997.

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Lens design. 3rd ed. New York: Marcel Dekker, 2001.

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Laikin, Milton. Lens design. 2nd ed. New York: Marcel Dekker, Inc., 1995.

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Laikin, Milton. Lens design. 2nd ed. New York: Marcel Dekker, Inc, 1995.

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Contact lens complications. Oxford: Butterworth-Heinemann, 1999.

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10

Ebenhardt, Alayne M. A lovely lens. Port Sydney, Ont: Dog House Pub., 2005.

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Book chapters on the topic "Lens"

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Hanks, Laura Hourston. "Louvre-Lens, Lens, France." In New Museum Design, 125–38. Abingdon, Oxon ; New York : Routledge, 2020.: Routledge, 2021. http://dx.doi.org/10.4324/9780429435591-7.

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Yu, Johan. "Lens." In Getting Started with Salesforce Einstein Analytics, 73–86. Berkeley, CA: Apress, 2019. http://dx.doi.org/10.1007/978-1-4842-5200-0_5.

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Krieglstein, Günter K., Christian P. Jonescu-Cuypers, Maria Severin, and Michael A. Vobig. "Lens." In Atlas of Ophthalmology, 123–43. Berlin, Heidelberg: Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/978-3-642-57132-9_6.

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Stefani, Fritz H., and Gerhard Hasenfratz. "Lens." In Macroscopic Ocular Pathology, 91–96. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-71796-3_8.

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Lee, W. R. "Lens." In Ophthalmic Histopathology, 313–27. London: Springer London, 1993. http://dx.doi.org/10.1007/978-1-4471-3843-3_14.

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Lee, William R. "Lens." In Ophthalmic Histopathology, 443–60. London: Springer London, 2002. http://dx.doi.org/10.1007/978-1-4471-3910-2_14.

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Naumann, G. O. H. "Lens." In Pathology of the Eye, 509–55. New York, NY: Springer New York, 1986. http://dx.doi.org/10.1007/978-1-4613-8525-7_9.

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Berman, Elaine R. "Lens." In Biochemistry of the Eye, 201–90. Boston, MA: Springer US, 1991. http://dx.doi.org/10.1007/978-1-4757-9441-0_5.

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Roberts, Fiona, and Chee Koon Thum. "Lens." In Lee's Ophthalmic Histopathology, 439–54. London: Springer London, 2013. http://dx.doi.org/10.1007/978-1-4471-2476-4_14.

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Nita, Stefania Loredana, and Marius Mihailescu. "Lens." In Haskell Quick Syntax Reference, 145–51. Berkeley, CA: Apress, 2019. http://dx.doi.org/10.1007/978-1-4842-4507-1_20.

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Conference papers on the topic "Lens"

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Ueda, Naoki, Masaru Sasago, Akio Misaka, Hisao Kikuta, Hiroaki Kawata, and Yoshihiko Hirai. "Built-in lens mask lithography: challenge for high definition lens-less lithography." In Photomask Japan 2014, edited by Kokoro Kato. SPIE, 2014. http://dx.doi.org/10.1117/12.2065251.

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Chaves, Julio, Juan C. Minano, and Pablo Benitez. "Afocal video-pixel lens for tricolor LEDs." In Optics & Photonics 2005, edited by Roland Winston and R. John Koshel. SPIE, 2005. http://dx.doi.org/10.1117/12.620148.

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Ju, Xi, Hongwei Zhang, Wenjie Zeng, Mukundan Sridharan, Jing Li, Anish Arora, Rajiv Ramnath, and Yufeng Xin. "LENS." In the 6th ACM international workshop. New York, New York, USA: ACM Press, 2011. http://dx.doi.org/10.1145/2030718.2030727.

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Courtial, Johannes, Tomáš Tyc, Jakub Bělín, Stephen Oxburgh, Euan Cowie, and Chris D. White. "Ideal-lens cloak and omnidirectional lens." In Frontiers in Optics. Washington, D.C.: OSA, 2017. http://dx.doi.org/10.1364/fio.2017.jtu2a.45.

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Clark, Peter P. "1985 International Lens Design Conference Lens Design Problem: A Reversible Lens." In 1985 International Lens Design Conference, edited by Duncan T. Moore and William H. Taylor. SPIE, 1986. http://dx.doi.org/10.1117/12.949260.

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Schelkanova, I., A. Pandya, G. Macdonald, D. Shah, L. Lilge, and A. Douplik. "Microvascular Patterns Monitoring Via Lens Less CMOS Chip." In Biomedical Optics. Washington, D.C.: OSA, 2014. http://dx.doi.org/10.1364/biomed.2014.bs3a.48.

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Murata, Osamu, Hiroyuki Toge, and Kunihiro Sato. "Lens-less holographic microscope with large visual depth." In SPIE OPTO: Integrated Optoelectronic Devices, edited by Hans I. Bjelkhagen and Raymond K. Kostuk. SPIE, 2009. http://dx.doi.org/10.1117/12.808766.

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Fatemi, Reza, Behrooz Abiri, and Ali Hajimiri. "An 8×8 Heterodyne Lens-less OPA Camera." In CLEO: Applications and Technology. Washington, D.C.: OSA, 2017. http://dx.doi.org/10.1364/cleo_at.2017.jw2a.9.

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Wagner, Omer, Aditya Pandya, Yoav Chemla, Hadar Pinhas, Irina Schelkanova, Asaf Shahmoon, Yossi Mandel, Alexandre Douplik, and Zeev Zalevsky. "Lens-less Micro-endoscopy through highly scattering media." In CLEO: Applications and Technology. Washington, D.C.: OSA, 2018. http://dx.doi.org/10.1364/cleo_at.2018.jtu2a.107.

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Sato, Kunihiro, and Osamu Murata. "Lens-less holographic microscope with high resolving power." In OPTO, edited by Hans I. Bjelkhagen and Raymond K. Kostuk. SPIE, 2010. http://dx.doi.org/10.1117/12.843481.

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Reports on the topic "Lens"

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Krider, J. Lithium Lens Interlocks. Office of Scientific and Technical Information (OSTI), December 1985. http://dx.doi.org/10.2172/948901.

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Primas, Lori Ellen. SQS Fiber Lens Array. Office of Scientific and Technical Information (OSTI), November 2018. http://dx.doi.org/10.2172/1482901.

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Mallett, Michael Wesley. Lens of Eye Dosimetry. Office of Scientific and Technical Information (OSTI), March 2015. http://dx.doi.org/10.2172/1209275.

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Birge, Noah Watson, and Verena Geppert-Kleinrath. MixIT LDRD Lens Design. Office of Scientific and Technical Information (OSTI), June 2020. http://dx.doi.org/10.2172/1633554.

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Xue, Liang, and Vincent Fusco. Electronically Reconfigurable Microwave Lens Antennas. Fort Belvoir, VA: Defense Technical Information Center, December 2005. http://dx.doi.org/10.21236/ada445588.

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Marshall, P. The SNAP Strong Lens Survey. Office of Scientific and Technical Information (OSTI), January 2005. http://dx.doi.org/10.2172/839722.

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Seryi, Andrei. Tevatron Electron Lens Magnetic System. Office of Scientific and Technical Information (OSTI), October 2001. http://dx.doi.org/10.2172/798884.

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Andresky, Nikolai L. HAMAS through a Constructivist Lens. Fort Belvoir, VA: Defense Technical Information Center, September 2008. http://dx.doi.org/10.21236/ada510054.

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Vigil, M. G. Plane shock generator explosive lens. Office of Scientific and Technical Information (OSTI), May 1996. http://dx.doi.org/10.2172/245662.

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Мінтій, Ірина Сергіївна, Тетяна Анатоліївна Вакалюк, and Світлана Миколаївна Іванова. Огляд можливостей онлайн-сервісу Lens. ЧДТУ, 2022. http://dx.doi.org/10.31812/123456789/6468.

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Abstract:
Під час написання дослідження велике значення від самого початку має зручність і швидкість виконання усіх процесів – від самого початку – пошуку матеріалів, їх аналізу аж до завершення певного етапу і поширення результатів. Більшість користувачів використовують для різних процесів різні сервіси – це можуть бути і звичайні пошукові системи, наукометричні бази даних, бібліотечні референс-менеджери, сповіщення, підписки та інше. Проте існують сервіси, що надають можливість виконувати усі ці дії. Наприклад, онлайн-сервіс Lens. Вітчизняні розробки щодо використання цього сервісу станом на сьогодні відсутні. В роботі розглянуто основні аспекти щодо пошуку, аналізу, упорядкування, оновлення та поширення матеріалів дослідження, використовуючи сервіс Lens. Сервіс має інтуїтивно зрозумілий інтерфейс. Lens має набагато ширші можливості, ніж це розглянуто у дослідженні, а їх розгляд є напрямом подальших досліджень.
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