Статті в журналах: "Coefficient of transmittance"

1

Hendricks, T. J., and J. R. Howell. "New Radiative Analysis Approach for Reticulated Porous Ceramics Using Discrete Ordinates Method." Journal of Heat Transfer 118, no. 4 (November 1, 1996): 911–17. http://dx.doi.org/10.1115/1.2822588.

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A novel radiative modeling technique using discrete ordinates has been developed for reticulated porous ceramics (RPCs) from experimental measurements of transmittance and reflectance on small samples of partially stabilized zirconium oxide (PS ZrO2) and oxide-bonded silicon carbide (OB SiC). The new technique defines and quantifies the direct transmittance fraction, fdt, of a reticulated porous ceramic, demonstrates how it redefines the extinction process, and creates a new effective extinction coefficient, Kλ,eff. This ultimately produces a modified form of the radiative transfer equation (RTE) and an innovative discrete ordinates formulation to solve the RTE unique to RPCs. The direct transmittance modeling approach has been compared to a more conventional homogeneous modeling approach, in which the direct transmittance effects are essentially ignored and the RPC is treated as a homogeneous lump of material. The two modeling approaches yield identical results in predicting small test sample reflectances and transmittances. The direct transmittance technique does demonstrate explicitly, through a unique relationship between absorption coefficients in the two modeling approaches, the importance of scattering processes in enhancing the absorption mechanism in RPCs. It can also be an important secondary modeling technique that imposes additional parameter constraints in an inverse analysis to help refine derived radiative coefficients.

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2

Kanayama, K., and H. Baba. "Transmittance of Distilled Water and Sodium-Chloride-Water Solutions." Journal of Solar Energy Engineering 110, no. 2 (May 1, 1988): 113–19. http://dx.doi.org/10.1115/1.3268240.

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The spectral transmittance of pure water and salt water solutions of various concentrations, which are important for the thermal calculation of a solar pond, is measured experimentally for specimen thickness of 1 to 100 mm by means of an autorecording spectro-radiometer inside an air-conditioned room. On the basis of the measured spectral transmittance, the total transmittance of pure and salty waters to 3 m of water depth is calculated as a ratio of the total radiation energy over all wavelengths arriving at any depth from the water surface of the solar pond to the solar radiation incident upon the water surface with various air masses. According to Nielsens’ four-partition method, the effective absorption coefficient is calculated for each wavelength band. Lastly, the transmission properties obtained for pure water, i.e., spectral and total transmittances, absorption wavelength band, and effective absorption coefficient, are compared with past results, and those for salty water with various concentrations are compiled as basic data for the use of solar energy by a solar pond.

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3

Hayashi, Takahiro, Takayuki Kobayashi, and Jun Takahashi. "Quantification of the void content of composite materials using soft X-ray transmittance." Journal of Thermoplastic Composite Materials 30, no. 11 (April 24, 2016): 1522–40. http://dx.doi.org/10.1177/0892705716644670.

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Carbon fiber reinforced thermoplastics (CFRTPs) have high potential in high-cycle (1 min) molding as a weight-reducing material for the mass production of automobile components. However, residual voids in CFRTPs lead to diminished and unstable mechanical properties; therefore, the effective quantification of the void content in CFRTP products is necessary for developing an affordable system for mass production. In a previous study, we demonstrated that the X-ray attenuation coefficient decreases with increasing void content; thus, measurements of X-ray attenuation coefficients can be used to estimate the void contents of CFRTPs. In this study, we first investigated in detail the soft X-ray attenuation coefficients of completely impregnated composite materials with three different thicknesses; we observed that the attenuation coefficients decreased with increasing composite thickness, even though they should be independent of the thickness according to the Beer–Lambert law. We next demonstrated that although no correlation exists between the X-ray transmittance and the apparent attenuation coefficient of six composites with various void contents, the true attenuation coefficient modified to account for void content exhibits a good linear relationship with the X-ray transmittance, same as fully impregnated composites. Using the approximation line between the X-ray transmittance and the modified attenuation coefficient of CFRTP, we estimated the void content on the basis of the difference between the apparent and true X-ray attenuation coefficients. The average difference in void content determined by conventional hydrostatic weighing and that determined by the proposed X-ray transmittance method was 0.43%. We therefore concluded that the void content of CFRTPs of any thickness can be estimated nondestructively using soft X-rays.

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4

Peris-Martínez, Cristina, Mari Carmen García-Domene, Mariola Penadés, María Josefa Luque, Ester Fernández-López, and José María Artigas. "Spectral Transmission of the Human Corneal Layers." Journal of Clinical Medicine 10, no. 19 (September 29, 2021): 4490. http://dx.doi.org/10.3390/jcm10194490.

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We have assessed the spectral transmittance of the different layers of the human cornea in the ultraviolet (UV), visible, and near-infrared (IR) spectral ranges. Seventy-four corneal sample donors were included in the study. Firstly, the corneal transmittance was measured using a spectrophotometer. Then, all samples were fixed for histopathological analysis, which allowed us to measure the thickness of each corneal layer. Finally, the absorption coefficients of the corneal layers were computed by a linear model reproducing total transmittance. The results show that corneal transmission was almost in unity at the visible and IR ranges but not at the UV range, in which the layer with higher transmission is Descemet’s membrane, whereas the stroma showed the lowest transmittance. Regarding the absorption coefficient, the most absorptive tissue was Bowman’s layer, followed by the endothelium. Variations on transmittance due to changes in the stroma, Bowman’s layer, or Descemet layer were simulated, and important transmission increases were found due to stroma and Bowman changes. To conclude, we have developed a method to measure the transmittance and thickness for each corneal layer. All corneal layers absorb UV light to a greater or lesser extent. The absorption coefficient is higher for Bowman’s layer, while the stroma is the layer with the lowest transmittance due to its thickness. Variations in stroma thickness or changes in the corneal tissue of Bowman’s layer or the endothelium layer due to some pathologies or surgeries could affect, to a greater or lesser degree, the total transmission of the cornea. Thus, obtaining accurate absorption coefficients for different layers would help us to predict and compensate these changes.

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5

Qi, Hanbing, Lu Yang, Xinhao Hu, Dong Li, Qiushi Wang, and Guozhong Wu. "Optical Properties of Oilfield Wastewater and its Application in Measuring Oil Content." Applied Spectroscopy 72, no. 8 (June 18, 2018): 1252–57. http://dx.doi.org/10.1177/0003702818767405.

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Optical properties of oilfield wastewater play an important role in the on-line measurement of oil content. As an important parameter of optical properties, absorption coefficient is usually obtained by indirectly modeling transmittance spectra. In this work, transmittance spectra of oilfield wastewater in the wavelength range of 190–900 nm at normal incidence were measured by TU-1900 double beam ultraviolet visible spectrophotometer. The absorption coefficient of oilfield wastewater was obtained by a double thickness method, and the relationship between the oil content in oilfield wastewater and its absorption coefficient was studied. The results show that the transmittance spectra of oilfield wastewater decrease with the increase of oil content. The oil content of oilfield wastewater is found to correlate negatively with its transmittance. The oil content of oilfield wastewater and its absorption coefficient have a good fitting effect at 234 nm, and the fitting error of three order polynomial fitting is minimal, with a range of 0.02–5.39%, and the fitting accuracy is 0.9940.

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6

Pereyra, Pedro. "Photonic Transmittance in Metallic and Left Handed Superlattices." Photonics 7, no. 2 (April 18, 2020): 29. http://dx.doi.org/10.3390/photonics7020029.

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We study the transmission of electromagnetic waves through layered structures of metallic and left-handed media. Resonant band structures of transmission coefficients are obtained as functions of the incidence angle, the geometric parameters, and the number of unit cells of the superlattices. The theory of finite periodic systems that we use is free of assumptions, the finiteness of the periodic system being an essential condition. We rederive the correct recurrence relation of the Chebyshev polynomials that carry the physical information of the coherent coupling of plasmon modes and interface plasmons and surface plasmons, responsible for the photonic bands and the resonant structure of the surface plasmon polaritons. Unlike the dispersion relations of infinite periodic systems, which at best predict the bandwidths, we show that the dispersion relation of this theory predicts not only the bands, but also the resonant plasmons’ frequencies, above and below the plasma frequency. We show that, besides the strong influence of the incidence angle and the characteristic low transmission of a single conductor slab for frequencies ω below the plasma frequency ω p , the coherent coupling of the bulk plasmon modes and the interface surface plasmon polaritons lead to oscillating transmission coefficients and, depending on the parity of the number of unit cells n of the superlattice, the transmission coefficient vanishes or amplifies as the conductor width increases. Similarly, the well-established transmission coefficient of a single left-handed slab, which exhibits optical antimatter effects, becomes highly resonant with superluminal effects in superlattices. We determine the space-time evolution of a wave packet through the λ / 4 photonic superlattice whose bandwidth becomes negligible, and the transmission coefficient becomes a sequence of isolated and equidistant peaks with negative phase times. We show that the space-time evolution of a Gaussian wave packet, with the centroid at any of these peaks, agrees with the theoretical predictions, and no violation of the causality principle occurs.

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7

Geyer, Christoph, Andreas Müller, and Barbara Wehle. "Measurements of thermal Transmittance of an External massive timber wall in-situ and in the Laboratory." E3S Web of Conferences 172 (2020): 14009. http://dx.doi.org/10.1051/e3sconf/202017214009.

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The thermal transmittance of an exterior massive timber wall was measured in situ in Appenzell, Switzerland according to the standard ISO 9869-1. The measurements were performed with two different measurement sets in parallel. The measurements started in February and stopped at end of April. The measuring data were analyzed using mean values of the thermal transmittance coefficient and of the thermal resistance following the procedure of ISO 9869-1. In order to clarify if the in-situ measurement results show significant deviations from the measurement results of the thermal transmittance obtained in the laboratory, the thermal transmittance of the identical wall construction was measured in the laboratory of Bern University of Applied Sciences in Biel according to the standard EN ISO 8990 for steady state boundary conditions in a guarded and calibrated hot box. The test results will be presented and the measurement setup will be described. The calculation value of the thermal transmittance coefficient of the massive timber wall according to EN ISO 6946 is U = 0.53 W/(m2K). The test results of the thermal transmittance coefficient, U-value of the wall, measured in the hot box, agreed well within a confidence level of 95 % with the calculated value. The in-situ measurement results of the thermal transmittance coefficient of the two measurement sets differ significantly in the order of 8 % referred to the calculated U-value of the wall as the basic amount. Furthermore, both in situ test results of the U-value of the wall show significant deviations from the calculated U-value up to 27 %.

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8

Burger, T., J. Kuhn, R. Caps, and J. Fricke. "Quantitative Determination of the Scattering and Absorption Coefficients from Diffuse Reflectance and Transmittance Measurements: Application to Pharmaceutical Powders." Applied Spectroscopy 51, no. 3 (March 1997): 309–17. http://dx.doi.org/10.1366/0003702971940404.

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A measurement and data evaluation technique for the separate determination of the scattering and absorption properties of loose pharmaceutical powders is described. The equation of radiative transfer for diffuse reflectance and transmittance is analytically solved by using a three-flux approximation. Combined transmittance and reflectance measurements then allow one to derive both the scattering and the absorption coefficients. The scattering and absorption coefficients provide more information about particle size, degree of agglomeration, and chemical composition of the samples in comparison to the usual determination of only the ratio of the coefficients from diffuse reflectance measurements on optically thick samples. Furthermore, the theory of diffuse reflectance of optically thick samples according to Kubelka and Munk is compared to the three-flux approximation. The influence of the particle size on the scattering and absorption coefficient is investigated, and it is shown that the assumption of a wavelength-independent scattering coefficient, though often made in reflectance spectroscopy, is not generally valid.

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9

Journal, Baghdad Science. "Effects of Non-Thermal Argon Plasma Produced at Atmospheric Pressure on the Optical Properties of CdO Thin Films." Baghdad Science Journal 15, no. 2 (June 4, 2018): 221–26. http://dx.doi.org/10.21123/bsj.15.2.221-226.

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In this paper the effect of nonthermal atmospheric argon plasma on the optical properties of the cadmium oxide CdO thin films prepared by chemical spray pyrolysis was studied. The prepared films were exposed to different time intervals (0, 5, 10, 15, 20) min. For every sample, the transmittance, Absorbance, absorption coefficient, energy gap, extinction coefficient and dielectric constant were studied. It is found that the transmittance and the energy gap increased with exposure time, and absorption. Absorption coefficient, extinction coefficient, dielectric constant decreased with time of exposure to the argon plasma

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10

Abass, Khalid Haneen. "Spray Pyrolysis Deposition and Effect of Annealing Temperature on Optical Properties of Cu:NiO Film." International Letters of Chemistry, Physics and Astronomy 47 (February 2015): 178–84. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.47.178.

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Spray pyrolysis method that used to prepare Cu:NiO thin films onto glass substrate with various annealing temperature. Spectral transmittance of prepared thin films determined by UV-Visible spectrophotometer in the range of (380-900) nm. The transmittance decreased with increasing annealing temperature. While the absorption coefficient and extinction coefficient increased with increasing annealing temperature. Energy gap decreased from 2.9 eV before annealing to 2.78 eV after 500 °C annealing temperature.

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11

Zhao, Jiandong, Mingmin Han, Changcheng Li, and Xin Xin. "Visibility Video Detection with Dark Channel Prior on Highway." Mathematical Problems in Engineering 2016 (2016): 1–21. http://dx.doi.org/10.1155/2016/7638985.

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Dark channel prior (DCP) has advantages in image enhancement and image haze removal and is explored to detect highway visibility according to the physical relationship between transmittance and extinction coefficient. However, there are three major error sources in calculating transmittance. The first is that sky regions do not satisfy the assumptions of DCP algorithm. So the optimization algorithms combined with region growing and coefficient correction method are proposed. When extracting atmospheric brightness, different values lead to the second error. Therefore, according to different visibility conditions, a multimode classification method is designed. Image blocky effect causes the third error. Then guided image filtering is introduced to obtain accurate transmittance of each pixel of image. Next, according to the definition meteorological optical visual range and the relationship between transmittance and extinction coefficient of Lambert-Beer’s Law, accurate visibility value can be calculated. A comparative experimental system including visibility detector and video camera was set up to verify the accuracy of these optimization algorithms. Finally, a large number of highway section videos were selected to test the validity of DCP method in different models. The results indicate that these detection visibility methods are feasible and reliable for the smooth operation of highways.

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12

Palková, Adela, and Milan Palko. "Theoretical Calculation of Thermal Transmittance." Applied Mechanics and Materials 820 (January 2016): 212–17. http://dx.doi.org/10.4028/www.scientific.net/amm.820.212.

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The article is focused on the theoretical calculation of thermal transmittance for new plastic window frame. Constant making the thermos-technical requirements stricter lays higher demands on improvement of window frames which the weakest element from the point of heat engineering. One important part of the window, which is needed to be improved, is a frame profile. Assessment of newly proposed window profile system is realised based on currently effective technical norms and regulations. The main aim of the theoretical assessment and computer simulation is to define the coefficient of passage of heat of the frame construction of a new plastic profile system.

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13

Kayani, Zohra Nazir, Maryam Iqbal, Saira Riaz, Rehana Zia, and Shahzad Naseem. "Fabrication and properties of zinc oxide thin film prepared by sol-gel dip coating method." Materials Science-Poland 33, no. 3 (September 1, 2015): 515–20. http://dx.doi.org/10.1515/msp-2015-0085.

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AbstractZnO thin films were deposited on a glass substrate by dip coating technique using a solution of zinc acetate, ethanol and distilled water. Optical constants, such as refractive index n and extinction coefficient k. were determined from transmittance spectrum in the ultraviolet-visible-near infrared (UV-Vis-NIR) regions using envelope methods. The films were found to exhibit high transmittance, low absorbance and low reflectance in the visible regions. Absorption coefficient α and the thickness of the film t were calculated from interference of transmittance spectra. The direct optical band gap of the films was in the range of 3.98 to 3.54 eV and the thickness of the films was evaluated in the range of 173 to 323 nm, while the refractive index slightly varied in the range of 1.515 to 1.622 with an increase in withdrawal speed from 100 to 250 mm/s. The crystallographic structure of the films was analyzed with X-ray diffractometer. The films were amorphous in nature.

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14

Zhu, Wenqi, Xingzhong Guo, Lan Wu, and Hui Yang. "Simulation of the Light Transmittance in Macroporous Silica." Materials 13, no. 7 (April 1, 2020): 1635. http://dx.doi.org/10.3390/ma13071635.

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This paper focuses on the light transmittance of macroporous silica as a photocatalyst carrier. In addition to the characteristics of photocatalysts, the structure of porous bulk is also important since it affects the propagation of light. Realistic porous structures are generated by a Voronoi-based approach. Four morphological parameters are highly controlled during generating, that is, porosity, coefficient of variation, diameter ratio and normalized curvature. Finite element method (FEM) is used to simulate the propagation of light in the porous models in the visible light range. The intensity shows a quadratic decrease with the increase of the depth of light propagation. The influences of the morphological parameters on the light transmittance are analysed. It turns out that the porosity has a great influence on the light transmittance while the coefficient of variation and the diameter ratio have small ones. Moreover, the influence of the normalized curvature is little. Besides, the effect of the wavelength of visible light can not be ignored. With the simulation, the depth of visible light entering the porous silica can be estimated, which is challenging to access experimentally.

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15

Khan, Muhammad Irshad, Muhammad Irfan Khattak, and Mauth Al-Hasan. "Miniaturized MIMO Antenna with Low Inter-radiator Transmittance and Band Rejection Features." Journal of Electromagnetic Engineering and Science 21, no. 4 (September 30, 2021): 307–15. http://dx.doi.org/10.26866/jees.2021.4.r.38.

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In this article, compact a multiple-input and multiple-output (MIMO) system with flag-shaped radiators and a mountain-shaped ground plane is presented. Isolation is enhanced with the help of a decoupling stub placed between radiators, where two bands are stopped with the help of slits etched into the radiators. The overall size of the proposed antenna is 15 mm ×25 mm ×1.6 mm. The reflection coefficients are less than -10 dB between 3–10.9 GHz, except the bands WiMAX (3.2–3.7 GHz) and WLAN (5–6 GHz); similarly, measured and simulated transmission coefficients are less than -20 dB across the entire band of UWB. The envelope correlation coefficient (ECC) is less than 0.02 and the diversity gain is greater than 9.9 dB. The gain, ECC, radiation pattern, multiplexing efficiency, diversity gain and various other parameters are discussed and evaluated in detail.

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16

Burger, T., H. J. Ploss, J. Kuhn, S. Ebel, and J. Fricke. "Diffuse Reflectance and Transmittance Spectroscopy for the Quantitative Determination of Scattering and Absorption Coefficients in Quantitative Powder Analysis." Applied Spectroscopy 51, no. 9 (September 1997): 1323–29. http://dx.doi.org/10.1366/0003702971941999.

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A three-flux approximation of the equation of radiative transfer is used to separately determine the effective specific scattering and absorption coefficients of powder mixtures from hemispherical reflectance and transmittance measurements. For a two-component mixture of lactose and paracetamol, it is demonstrated how the knowledge of the separately known scattering coefficient can be used to improve partial least-squares regression (PLS) calibrations of diffuse reflectance data pretreated by multiplicative scatter correction (MSC). Furthermore it is shown that the measured specific absorption coefficient of the investigated mixtures is not generally a linear function of the constituents concentration, a result which might be caused by the mixing procedure of the samples. With the use of the absorption coefficient, it is demonstrated that artificial neural networks are superior to PLS calibrations when modeling a nonlinear relation.

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17

Palková, Adela, and Milan Palko. "Material Properties of Windows in the Building Energy Concept." Advanced Materials Research 855 (December 2013): 116–19. http://dx.doi.org/10.4028/www.scientific.net/amr.855.116.

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The window is an exposed part of the external cladding. Assessment of windows regarding the heat transfer coefficient. Categorization of thermo-technical requirements for windows. Experimental measurement and determination of heat transfer coefficient. Calculation and determination of linear thermal transmittance. Material base of windows for passive energy building standard.

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18

Kirchner, Sara, Sebastien Narinsamy, Alain Sommier, Marta Romano, Meguya Ryu, Junko Morikawa, Jacques Leng, Jean-Christophe Batsale, and Christophe Pradère. "Calibration Procedure for Attenuation Coefficient Measurements in Highly Opaque Media Using Infrared Focal Plane Array (IRFPA) Spectroscopy." Applied Spectroscopy 72, no. 2 (January 9, 2018): 177–87. http://dx.doi.org/10.1177/0003702817736320.

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The purpose of this article is to present a new calibration procedure for spectroscopic measurements using an infrared focal plane array (IRFPA) spectrometer on highly opaque middle-wave infrared (MWIR) media. The procedure is based on the properties of the IRFPA camera and especially the integration time (IT), which is the main parameter that can be adjusted to control the sensitivity of the measurements. The goal of the paper is to experimentally validate this dependence with the direct reference intensity light coming out of the IR monochromator in order to predict the spectrum shape and intensity level in a range out of the camera saturation. This method allows determining spectrum used as background for transmittance calculation. It has been applied in the case of measurement of water transmittance, which is a highly opaque medium and whose measurement requires high ITs. The main result is the ability to take an IR spectroscopic imaging measurement through 300 µm of water and the determination of its transmittance with sufficient sensitivity due to the proposed calibration procedure. This procedure allows the possibility of transitory studies in heterogeneous aqueous media.

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19

Journal, Baghdad Science. "The Effect of Chlorine Concentration on the Optical Constants of SnS Thin Films." Baghdad Science Journal 8, no. 2 (June 12, 2011): 566–70. http://dx.doi.org/10.21123/bsj.8.2.566-570.

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Chlorine doped SnS have been prepared utilizing chemical spray pyrolysis. The effects of chlorine concentration on the optical constants were studied. It was seen that the transmittance decreased with doping, while reflectance, refractive index, extinction coefficient, real and imaginary parts of dielectric constant were increased as the doping percentage increased. The results show also that the skin depth decrease as the chlorine percentage increased which could be assure that it is transmittance related.

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20

Brown, Martin J., and Geoffrey G. Parker. "Canopy light transmittance in a chronosequence of mixed-species deciduous forests." Canadian Journal of Forest Research 24, no. 8 (August 1, 1994): 1694–703. http://dx.doi.org/10.1139/x94-219.

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We measured the photosynthetically active radiation transmitted through the canopies of 24 Maryland forest stands, each around midday in midsummer. We then compared the observed values of PAR transmittance with stand age and measures of canopy structure. Generally, transmittance was low, with positively skewed frequency distributions. The geometric mean transmittance followed a distinct pattern with stand age. It was lowest (about 1%) in the youngest stands, increased to about 2.5% as forests approached ages of about 50 years, and then declined with age in the oldest sites (65–340 years). Transmittance was not significantly correlated with many simple measures of forest structure, including estimated aboveground biomass and leaf area index. Better predictions of transmittance used information on the vertical arrangement of the canopy, such as leaf area density. The results are contrary to the common assumptions that forests get consistently darker through time, and that transmittance is inversely proportional to the sheer mass or leaf area of the canopy. The Beer–Lambert extinction coefficient, k, changed with stand age and structure and was especially high in very young stands. We suggest that the variation in light transmittance, and k, can be explained by successional changes in the three-dimensional structure of the canopy.

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21

Mangthong, Pornnapha, Phalatt Leowkijsiri, Nattapon Srisittipokakun, and Jakrapong Kaewkhao. "Comparison and Transmission Studies of Commercial Glass and Laminated Glass with PDLC Film for Heat Resistant and Other Building Structure Applications." Solid State Phenomena 305 (June 2020): 103–7. http://dx.doi.org/10.4028/www.scientific.net/ssp.305.103.

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The work emphasizes on energy saving in multi-layered glasses. Appropriate multi-layer designing was envisaged with various possibility and measured the transmittance of light in UV-Vis-NIR range. Various glasses were selected to study their transmittance for their specific advantages among each other for designing the multi-layer.Visible region showing higher transmittance revealing that these glasses allows more light in this range. While in the IR region these glasses show less transmittance revealing that these glasses doesn’t transmit much heat, this being the interest of study to stack the glasses for multi-layered glass with smart film then subjected to study their optical behavior and understood their energy saving phenomenon from window 6 program to obtain Solar Heat Gain Coefficient (SHGC) and Light to Solar Gain (LSG) data. Such multi-layered glasses can be used as a database in industrial plants.

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22

Gao, Xiao Long, Da Ming Wu, Ya Jun Zhang, Xiu Ting Zheng, and Yan Liu. "Investigation on Transmittance and Uniformity of Light Diffuser Plate of Filling Coefficient of Microstructure." Advanced Materials Research 683 (April 2013): 185–90. http://dx.doi.org/10.4028/www.scientific.net/amr.683.185.

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In this paper, the filling coefficient is defined by the ratio between effective by light area and the total area of the light diffuser when a beam of light strikes it, namely micro lens array structure of configuration density. In order to analyze the relation between the filling coefficient of the microstructure and the optical properties of the diffuser, the filling coefficient is expressed as center-to-center spacing of the microstructure.As the the center-to-center spacing increases,the filling coefficient becomes smaller.and the relation between the filling coefficient of the diffuser microstructure and the optical properties of diffuser have also been simulated by the Light Tools software based on the Monte-Carlo Method. Then the test sample which has the same aspect ratio and filling coefficient with the simulation sample has been obtained by using micro injection casting, Comparing the haze and transmittance of the experimental diffuser with the simulation result, the relation between the filling coefficient of the diffuser microstructure and the optical properties of diffuser have been gotten.

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23

Zeng, J. S. Q., R. Greif, P. Stevens, M. Ayers та A. Hunt. "Effective optical constants n and κ and extinction coefficient of silica aerogel". Journal of Materials Research 11, № 3 (березень 1996): 687–93. http://dx.doi.org/10.1557/jmr.1996.0083.

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In this work the normal reflectance, R, at a planar silica aerogel interface and the normal transmittance, T, of a silica aerogel slab were measured using a Fourier Transform Infrared Spectrometer. Two procedures were used to obtain the effective optical constants, i.e., the refractive index n and the absorption index κ, of silica aerogel. One procedure determined κ from the measured transmittance T and then determined n from the results for κ and from the measured reflectance R using the Kramers–Kronig relation; the other procedure determined n and κ of silica aerogel from n and κ of fully dense silica glass by using the Clausius–Mossotti equation, Maxwell Garnett formula, and Bruggeman formula. The first procedure has a relatively large error due to the inaccuracy of the transmission and reflection measurements. The second procedure, especially the Clausius–Mossotti equation, yields values of n that are consistent with experiments and may be used for the calculation of the effective optical constants and the extinction coefficient of silica aerogel.

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24

Aly, S. A. "Optical Characteristics of Tungsten Oxide Thin Films Prepared by Sputtering Technique." Defect and Diffusion Forum 295-296 (January 2010): 11–17. http://dx.doi.org/10.4028/www.scientific.net/ddf.295-296.11.

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The optical properties of tungsten oxide (WO3) films prepared by DC sputtering on unheated glass substrates with different film thicknesses have been studied. The structural characteristics of the samples were investigated using X-ray diffraction. The optical properties of the prepared films were studied by transmittance and reflectance measurements, and the integrated transmittance (TUV, TVIS, and TNIR) and absorption (AUV, AVIS, and ANIR) in UV, VIS and NIR regions. The integrated UV absorption and transmittance are varied with the film thicknesses, also, no remarkable change in VIS and NIR regions was observed. The dependence of refractive index as well as extinction coefficient on wavelength was also reported. The energy gap was calculated and is located around 3.25 eV.

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25

AHMAD, JAVED, SHER ALAM, JIANDING YU, and YASUTOMO ARAI. "EFFECT OF Ti ON THE OPTICAL BAND GAP OF FERROELECTRIC BaTixO5-BASED BULK GLASS." Modern Physics Letters B 23, no. 19 (July 30, 2009): 2377–83. http://dx.doi.org/10.1142/s0217984909020497.

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Optical transmittance on ferroelectric BaTi x O 5 (x=1.7, 2, 2.1)-based glasses prepared recently by a containerless synthesis technique is measured at room temperature in the wavelength range 190–800 nm. A sharp decrease in the transmittance observed in the ultraviolet (UV) region, which shifts toward longer wavelength region on increasing x is associated with fundamental absorption edge. From the linear region of the absorption coefficient calculated from the transmittance spectrum the optical band gap of 3.41 eV is estimated for x=1.7, which decreases on increasing x. The Urbach energy increases on increasing x demonstrating an increase of structural disorder in the ferroelectric BaTi x O 5 glass on increasing Ti concentration.

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26

Yao, Jian, and Jin Xu. "Monte Carlo Simulation for the Angle-Dependent Light Transmittance of Thermotropic Material." Applied Mechanics and Materials 29-32 (August 2010): 2781–84. http://dx.doi.org/10.4028/www.scientific.net/amm.29-32.2781.

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In this paper we propose a Monte-Carlo method for the simulation of the angle-dependent light transmittance of thermotropic material. The results show that the scattering light increased as temperature rose, and most of light transmitted went through the sample of thermotropic material at the angles between 10~40 deg. The results also indicate that the light transmittance measurement of thermotropic material by spectrophotometer without an integrating sphere is not accurate. As a conclusion, Monte Carlo simulation is an effective method for the determination of angle-dependent light transmittance of thermotropic material, and results of these simulations can be used to calculate the shading coefficient of window for building energy efficiency.

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27

ZHANG, L. F., X. DONG, J. XU, Y. G. JIANG, L. W. ZHOU, and Y. H. ZHU. "SHORT TIME DYNAMIC STRUCTURE FORMATION OF CARBON-DOPED TiO2 ER FLUIDS WITH DIFFERENT CONDUCTIVITY USING DIFFUSING WAVE SPECTROSCOPY." International Journal of Modern Physics B 16, no. 17n18 (July 20, 2002): 2321–27. http://dx.doi.org/10.1142/s021797920201230x.

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A new method of doing DWS (diffusing wave spectroscopy) measurement has been developed by using high speed CCD to investigate the structure and the dynamics of nonergodic and concentrated system such as electrorheological (ER) fluids under high electric field. The DWS results from the CCD method and the traditional method using a single-mode optical fiber agree well for ergodic system. The structure response time is obtained by measuring the transmittance of the sample under different electric field. The force response time of about 100ms is obtained from the time-dependent diffusion coefficient. In this paper, by comparing the time variation of transmittance and diffusion coefficient obtained under different conditions, a criterion of fast and strong responses of practical ER fluids to electric field is provided.

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28

Awad, Tabarak Mohammed, and May A. S. Mohammed. "Study the Effect of Heat Treatment and Pressure on some the Optical Properties of the Pure PVA Nano Polymer." Key Engineering Materials 900 (September 20, 2021): 16–25. http://dx.doi.org/10.4028/www.scientific.net/kem.900.16.

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In this study, some optical properties were studied of the pure vinyl polyvinyl alcohol (PVA) nanopolymer (German origin). Under the influence of different temperatures and pressures of PVA. Where 25 samples were prepared for the purpose of conducting the research. Which studied the study of these samples was done by recording the absorbance and transmittance spectra of the wavelengths (200-900) nm. From them, absorbance, transmittance, reflectivity, absorption coefficient, refractive index, extinction coefficient, complex dielectric constant were calculated. At different temperatures (25,40, 80, 120, 160)°C. And with different pressures within the range (7.5,8,8.5,9,9.5) MPa. The results are that the permeability of the polymer (PVA) at different temperatures for each pressure decreases with increasing temperature, and that all other calculated optical properties increase with increasing temperature.

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29

Al-Taa'y, Wasan A., and Bushra A. Hasan. "Structural and optical properties of TiO2:NiO nanoparticles thin films prepare by chemical spray pyrolysis." Iraqi Journal of Physics (IJP) 19, no. 49 (May 18, 2021): 22–31. http://dx.doi.org/10.30723/ijp.v19i49.632.

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The properties of structural and optical of pure and doped nano titanium dioxide (TiO2) films, prepared using chemical spray pyrolysis (CPS) technique, with different nanosize nickel oxide (NiO) concentrations in the range (3-9)wt% have been studied. X-Ray diffraction (XRD) technique where using to analysis the structure properties of the prepared thin films. The results revealed that the structure properties of TiO2 have polycrystalline structure with anatase phase. The parameters, energy gap, extinction coefficient, refractive index, real and imaginary parts were studied using absorbance and transmittance measurements from a computerized ultraviolet visible spectrophotometer (Shimadzu UV-1601 PC) in the wavelengths range (300-800)nm. Optical properties of TiO2 affected by the adding of NiO impurity where the transmittance increased as NiO concentration increased but with more adding the transmittance returned to decrease again. It was found the extinction coefficient, refractive index, real and imaginary parts values decreased with increasing doping percentage up to 7% and then increases occur one more again at 9%. Energy gap values increased after doping with NiO where the values lies in the range was 3.31 to 3.51 eV .

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30

Tang, Hua Juan. "A Free-Lead and Cadmium of Antimony Ruby Glass Composition and its Preparation Method." Advanced Materials Research 535-537 (June 2012): 2158–61. http://dx.doi.org/10.4028/www.scientific.net/amr.535-537.2158.

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The antimony ruby glass is prepared by soda-lime silica system as matrix composition which coefficient of linear expansion is appropriate for the ordinary glassware.UV-VIS spectrometer is used to measure the transmittance curves of various amount Sb2O3 glasses Relation between amount Sb2O3 and transmittance of antimony glasses are investigated which indicates that the tSuperscript textransmittance of antimony glass becomes lower with Sb2O3 amount increasing. Comparing un-treatment with heat treatment antimony glass, the dominate wavelength moves toward the red wavelength and the pure color increases.

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31

Journal, Baghdad Science. "The Effect of Thickness on Some Optical Properties of Sb2S3 Thin Films Prepared by Chemical Bath Deposition." Baghdad Science Journal 7, no. 1 (March 7, 2010): 168–73. http://dx.doi.org/10.21123/bsj.7.1.168-173.

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Sb2S3 thin films have been prepared by chemical bath deposition on a glas sub Absorbance and transmittance spectra were recorded in the wavelength range (30-900) nm. The effects of thickness on absorption coefficient, reflectance, refractive index, extinction coefficient, real and imaginary parts of dielectric constant were estimated. It was found that the reflectivity, absorption coefficient , extinction coefficient, real part of dielectric constant and refractive index, all these parameters decrease as the thickness increased, while the imaginary part of the dielectric constant increase as the thickness increased.

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32

Liu, Sanfeng, Hansheng Geng, Xinli Kong, Yinzhi Zhou, Peng Wang, and Fengnian Jin. "Experimental Study on the Propagation Law of Explosive Stress Wave in Cement Mortar with Weak Layers." Buildings 12, no. 5 (May 20, 2022): 687. http://dx.doi.org/10.3390/buildings12050687.

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The weak layer has good attenuation performance when it comes to the explosive stress wave, which can be used in protective structures. In this paper, a cement mortar specimen was designed, cast, and tested. Under inner explosion, due to the expansion of air in the explosive hole, the tensile cracks formed around the explosive hole are mainly in a damage pattern. In ordinary cement mortar, the transmittance is decreasing as the distance increases. At a distance of 8 cm to 14 cm from the explosive center, the average transmittance is 50.16%, 12 cm to 18 cm, while the average transmittance is 62.89%, increasing by 12.73%. Adding one weak layer into the cement mortar, the transmittance of one weak layer is 43.37%. The effect of increasing weak layers in short spacing is not obvious, and the transmittance of the second and third weak layer is about 80%, much less than the first layer. The softer the weak layer and the larger the wave impedance, the smaller the transmission coefficient is. The research proves that the weak layer has excellent attenuation performance when it comes to the explosive stress wave.

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33

Ashoor, Habib E., and Khalil Ebrahim Jasim. "Determining the optical properties of blood using He-Ne laser and double integrating sphere set-up." Polish Journal of Medical Physics and Engineering 25, no. 1 (March 1, 2019): 1–5. http://dx.doi.org/10.2478/pjmpe-2019-0001.

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Abstract The behaviour of light interaction with biological tissue is determined by micro-optical parameters: refractive index (n), absorption coefficient (µa), scattering coefficient (µs), and anisotropy (g). The goal of this study is to measure the optical properties of normal whole blood using He-Ne laser (wavelength 632.8 nm). The refractive index is measured using the traveller microscope. The integrating sphere method is used to measure the macro-optical parameters: total diffusive reflectance, transmittance, and collimated transmittance at wavelength 632.8 nm. The macro-optical parameters are fed to Inverse Adding Doubling (IAD) theoretical technique, to estimate the micro-optical parameters (µs, µa, g). An alternative practical method is used to measure the g value based on utilising the goniometric table. The study reveals that the refractive index (n) equals 1.395±0.0547, absorption coefficient (µa) equals 2.37 mm−1, scattering coefficient (µs) equals 55.69 mm−1, and anisotropy (g) equals 0.82. In conclusion, these findings approved, in general, the applicability of the suggested experimental set up. The set up depend on using three devices: the integrating sphere method to estimate (µs, µa, g), traveller microscope (n) and goniometer (g).

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34

Il'chuk, H., A. Kashuba, R. Petrus, I. Semkiv, and N. Ukrainets. "Simulation the spectral dependence of the transmittance for semiconductor thin films." Фізика і хімія твердого тіла 21, no. 1 (March 28, 2020): 57–60. http://dx.doi.org/10.15330/pcss.21.1.57-60.

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The spectral dependence of the transmittance as a function of the film thickness, the refractive index of the substrate, bandgap and the Cauchy parameters (α and β) of the semiconductor material was determined from condition of interference extremes. The absorption coefficient was simulated for the structure – thin film/substrate. Cadmium chalcogenides (CdTe, CdSe, and CdS) deposited on quartz substrates was selected as model samples. Experimental behavior of substrate transmittance was used to determine its refractive index. The theoretical results are compared with the experimental data and shows good agreement.

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35

Qiu Yang, 邱阳, 吕且妮 Lü Qieni, 赵爽 Zhao Shuang, and 周期辉 Zhou Qihui. "Simultaneous Measurement of Electrooptic Coefficient and Transmittance of KLTN Crystal with Digital Holography." Laser & Optoelectronics Progress 50, no. 9 (2013): 090902. http://dx.doi.org/10.3788/lop50.090902.

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36

Mogunde, Charles, and Cliff Orori Mosiori. "Transmittance and Extinction Coefficient of Sea and Well-Water in Mombasa County, Kenya." Path of Science 4, no. 10 (October 31, 2018): 3001–5. http://dx.doi.org/10.22178/pos.39-4.

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37

Sun, Guodong, Laian Qin, Zaihong Hou, Xu Jing, Feng He, Fengfu Tan, and Silong Zhang. "Small-scale Scheimpflug lidar for aerosol extinction coefficient and vertical atmospheric transmittance detection." Optics Express 26, no. 6 (March 14, 2018): 7423. http://dx.doi.org/10.1364/oe.26.007423.

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38

Domínguez-Gómez, A. B., R. A. Mauricio-Sánchez, and A. Mendoza-Galván. "Extinction coefficient of free-standing chitosan films determined from partially coherent transmittance spectra." Optical Materials 84 (October 2018): 564–71. http://dx.doi.org/10.1016/j.optmat.2018.07.059.

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39

Guketlov, Kh M., H. A. Khachetlov, and K. A. Kibishev. "Method for calculating the garret window light transmittance coefficient at clear sky CIE." IOP Conference Series: Materials Science and Engineering 913 (September 12, 2020): 042001. http://dx.doi.org/10.1088/1757-899x/913/4/042001.

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40

Gençyılmaz, O., F. Atay, and İ. Akyüz. "Photoluminescence, ellipsometric, optical and morphological studies of sprayed Co-doped ZnO films." Modern Physics Letters B 30, no. 15 (June 9, 2016): 1650171. http://dx.doi.org/10.1142/s0217984916501712.

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In this study, undoped and cobalt (Co)-doped zinc oxide (ZnO) films were successfully produced by ultrasonic spray pyrolysis (USP) technique at low temperature (350[Formula: see text]C). The optical and surface properties were investigated as a function of Co content. The optical parameters (thickness, refractive index and extinction coefficient) were determined using spectroscopic ellipsometry (SE) and it was seen that the refractive index and extinction coefficient values of Co-doped ZnO films decreased slightly depending on the increasing of Co doping. For investigation, the transmittance and photoluminescence (PL) spectra of the films, UV–Vis spectrophotometer and PL spectroscopy were used at room temperature. The transmittance spectra show that transmittance values decreased and Co[Formula: see text] ions substitute Zn[Formula: see text] ions of ZnO lattice. The optical band gap values decreased from 3.26 eV to 2.85 eV with the changing of Co content. The results of PL spectra exhibit the position of the different emission peaks unchanged but the intensity of peaks increased with increasing Co doping. Also, the surface properties of the films were obtained by atomic force microscopy (AFM) and these results indicated that the surface morphology and roughness values were prominently changed with Co doping.

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41

Järvinen, Onni, and Matti Leppäranta. "Transmission of solar radiation through the snow cover on floating ice." Journal of Glaciology 57, no. 205 (2011): 861–70. http://dx.doi.org/10.3189/002214311798043843.

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AbstractSpectral measurements of solar radiation in the band 400–900 nm were performed above and inside the snowpack in two locations in Finland, using a spectroradiometer. The transmittance and extinction coefficient were estimated for different snow layers. Four small candle-shaped photosynthetically active radiation (PAR) sensors were also used to measure the transfer of PAR inside the snowpack. In addition to the light measurements, physical characterization of snow stratigraphy was done, including the thickness, density, hardness (hand test), salinity, and grain size and shape (photographs of crystals). The transmittance varied from <1% (0–12 cm layer) to 80% (0–4 cm layer), and the extinction coefficient was between 0.03 cm−1 (4–8 cm layer) and 0.8 cm −1 (0–4 cm layer). The physical properties of the snow varied considerably between locations and days. The density of the snow varied between 140 and 480 kg m−3.

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42

Journal, Baghdad Science. "Effect of thickness on optical properties of pure Epoxy Resin plates." Baghdad Science Journal 11, no. 2 (June 1, 2014): 554–59. http://dx.doi.org/10.21123/bsj.11.2.554-559.

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In this study, Epoxy Resin plates was prepared by mixing epoxy(A) and hardner(B)with ratio(A:B) (3:1) with different thickness (0.3-0.96)cm. The effect of thickness on optical properties have been studied (absorption ,transmission ,reflectance) also the optical constant were found like (absorption coefficient, extenuation coefficient and refraction index) for all of the prepared plates. The results have shown that by increasing the thickness of plates., the absorption intensity increase in which at plates thickness (0.3-0.96)cm the absorption intensity were(1.54-1.43) respectively, and since absorption peak for epoxy occur in ultraviolet region and exactly at wavelength(368)nm and energy gap(Eg=3.05 eV) thus their good transmittance in the visible light region The plates have transmittance of about (60-83.4)% in visible region ,the refraction index for Elda epoxy is (n= 1.53 ) and its reflectance is (R=4 )% at wavelength (368 nm).

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43

Journal, Baghdad Science. "Annealing Effect on Some Optical Properties of Cr2O3 Thin Films Prepared by Spray Pyrolysis Technique." Baghdad Science Journal 8, no. 2 (June 12, 2011): 561–65. http://dx.doi.org/10.21123/bsj.8.2.561-565.

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Cr2O3 thin films have been prepared by spray pyrolysis on a glass substrate. Absorbance and transmittance spectra were recorded in the wavelength range (300-900) nm before and after annealing. The effects of annealing temperature on absorption coefficient, refractive index, extinction coefficient, real and imaginary parts of dielectric constant and optical conductivity were expected. It was found that all these parameters increase as the annealing temperature increased to 550°C.

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44

Chmúrny, Ivan. "Triple or Quadruple Glazing?" Applied Mechanics and Materials 820 (January 2016): 242–47. http://dx.doi.org/10.4028/www.scientific.net/amm.820.242.

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Comparison of basic thermal insulation properties of triple glazing and quadruple glazing. It also compares the heat transfer coefficient of glazing, transmittance of solar radiation, the weight of glass and other basic properties of glazing. It deals with the effect of number and position of low-emission coating the quadruple glazing on the heat transfer coefficient. Reducing weight of quadruple glazing using thin heat-strengthened glass and dimensional constraints.

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45

Chen, Zhuo, Jun Guo, Hao Li Qin, Hui Xie, Ke Jia Liu, Wei Zhao, and Ji Ping Liu. "Character and Preparation of Nano-SiO₂/PI Composites by Sol-Gel Method." Advanced Materials Research 924 (April 2014): 110–14. http://dx.doi.org/10.4028/www.scientific.net/amr.924.110.

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Polyimide/nano-SiO2 (PI/SiO2) composites with different contents of SiO2 were prepared by in situ polymerization. The transmittance, solubility, thermal property, flame retardant properties and mechanics properties of PI/nano-SiO2 composites were investigated. The results showed that with the increased addition of SiO2 content, the transmittance of PI/SiO2 compositions reduced; tensile strength changed with the amount of nanometer powder, when the addition content was 10 wt%, it achieve the maximum value. Thermal resistance of the composite was improved obviously while with the amount of nanometer powder increased, volume resistivity coefficient of volume resistance would have decreased.

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46

Li, Dong, Qing Ai та Xin Lin Xia. "Optical Constants of Quartz Glass in 1.34-4.20μm Spectral Range". Advanced Materials Research 652-654 (січень 2013): 523–26. http://dx.doi.org/10.4028/www.scientific.net/amr.652-654.523.

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The transmittance spectrograms of quartz glass slabs are measured in spectral range 1.34-4.20μm. A new inversion method of optical constants (k is extinction coefficient and n is refractive index) of glass was proposed to calculate the optical constants. The optical constants of selenide glass attained in the references were selected as the true values, and the spectral transmittance radio of the semitransparent solid based on the direct model simulation were regarded as the experimental values, and validation of the new inversion method was investigated. Then the optical constants of quartz glass were achieved by the inverse model.

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47

Ghimire, R. R., Y. P. Dahal, K. B. Rai, and S. P. Gupta. "Determination of Optical Constants and Thickness of Nanostructured ZnO Film by Spin Coating Technique." Journal of Nepal Physical Society 7, no. 2 (August 6, 2021): 119–25. http://dx.doi.org/10.3126/jnphyssoc.v7i2.38632.

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In this report, we have investigated optical constants and thickness of nanostructured ZnO films grown on a glass substrate by sol-gel spin coating technique using zinc acetate as precursor. Optical constants such as complex refractive index ñ and dielectric constant ϵ determined from the transmittance spectrum in the ultraviolet, visible, near infrared (UV-VIS, NIR) region by envelope method. The value of refractive index decreases from 2.34 to 1.86 and extinction coefficient increases from 0.28 to 0.64 with increasing wavelength. The decreasing behavior of refractive index is attributed due to the increase in transmission and decrease in absorption coefficient with increasing wavelength. The film exhibits reasonably high transmittance (>80%) in the visible region. Absorbance coefficient α and film thickness (d) were calculated from the interference of fringes of transmittance spectrum. The band gap and thickness of the film were found 3.02 eV and 275nm, respectively. The thickness of the film measured by envelope method is validated with cross-section micrograph of SEM images which is about 285 nm. The real part of the dielectric function of nanostructured ZnO decreases with increasing wavelength where as the imaginary part of dielectric constant increases with increasing wavelength. The observed high value of refractive index n and real part of dielectric constant ϵ at lower wavelength is due to band edge absorption of carriers. The dispersion relation shows the increase of complex refractive index and dielectric constant at the high frequency regime is due to the discharging of defect levels using optical excitation of carriers in the visible region.

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48

Mai, Zhi Jie, Fang Lin, and Jian Ming Fan. "Research of Monitoring Deterioration of Milk by Using Surface Tension Coefficient and Viscosity." Advanced Materials Research 455-456 (January 2012): 467–70. http://dx.doi.org/10.4028/www.scientific.net/amr.455-456.467.

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Nutrient-rich milk is the natural medium, easy to spoilage. Some physical parameters will change with milk deterioration such as density, viscosity, surface tension coefficient, light transmittance, etc. Detecting these physical parameters is useful to monitoring the deteriorate degree of milk. This article focuses on the surface tension efficient and viscosity of milk by monitoring its deteriorate process. The experimental results show that deterioration of milk is indeed accompanied with the change of surface tension coefficient and viscosity. In compare with surface tension coefficient, viscosity dramatically change after deterioration.

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49

Jandow, Nidhal Nissan. "Effects of Cu-Doping on Optical Properties of NiO." International Letters of Chemistry, Physics and Astronomy 48 (March 2015): 155–62. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.48.155.

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This work presents the effect of Cu-doping on some optical properties of Cu:NiO thin film prepared by spray pyrolysis technique. UV-Visible spectrophotometer in the range 380-900 nm used to determine the absorbance spectra for various Cu-doping of Cu:NiO thin film. The transmittance and energy gap are decreased with increasing Cu-doping in the prepared films, while absorption coefficient, extinction coefficient, and skin depth are increased with increasing Cu-doping.

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50

CRUZ, H., A. HERNANDEZ-CABRERA, and A. MUÑOZ. "RELATIVISTIC CORRECTIONS TO BALLISTIC QUANTUM TUNNELING THROUGH Ga1−xAlxAs BARRIERS." Modern Physics Letters B 05, no. 13 (June 10, 1991): 881–88. http://dx.doi.org/10.1142/s021798499100109x.

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Analytical solutions of a Dirac-type equation as effective mass equation. for electrons are obtained and by means of these solutions we have analytically calculated the relativistic transmission coefficient for quantum electron ballistic tunneling through Ga 1−x Al x As -GaAs single barriers. This solution for the transmission coefficient is applied to the tunnel injector of a hot electron device finding that relativistic corrections yield small but significant shifts in the transmittance-voltage characteristics.

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