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PURPOSE To investigate the contributions of ocular crystalline lens transmittance spectra and pupil size on age-related differences in the magnitude of light-induced melatonin suppression at night. The first aim was to demonstrate that spectral lens transmittance in children can be measured in vivo with a Purkinje image-based system. The second aim was to test the hypothesis that the magnitude of melatonin suppression in children is enhanced by larger pupils and higher lens transmittance of short wavelengths. METHODS Fourteen healthy children and 14 healthy adults participated in this study. The experiment was conducted for two nights in our laboratory. On the first night, the participants spent time under dim light conditions (

Optical properties of oily sewage play an important role in detection of water quality index of oily sewage. The transmittance spectra of oily sewage were investigated and the optical properties of oily sewage were calculated. Transmittance spectra were measured by a TU-1900 spectrophotometer in the range of 190˜900nm in pH of 6.5˜11.8. The oily sewage optical properties were calculated by the double thickness method, and the optical properties of oily sewage with different pH were compared. The results show that the transmittance of different optical path all decreased with the increase of pH in the range of 8.7˜11.8, and the transmittance in acidic environment is much higher than that in alkaline. In the wavelength of 240˜350 nm and 650˜850 nm, the pH has obvious influence on the refractive index. With the increase of pH in range of 8.7˜11.8, the absorption index has a significant downward trend. When pH is 9.6 and wavelength range is 300˜700nm, the effect of pH change on the refractive index is greater than that of the absorption index.When the solution is neutral, the fitting of the optical properties of oily sewage is the best.

The optical immersion clearing technique has been successfully applied through the last 30 years in the visible to near infrared spectral range, and has proven to be a promising method to promote the application of optical technologies in clinical practice. To investigate its potential in the ultraviolet range, collimated transmittance spectra from 200 to 1000 nm were measured from colorectal muscle samples under treatment with glycerol-water solutions. The treatments created two new optical windows with transmittance efficiency peaks at 230 and 300 nm, with magnitude increasing with glycerol concentration in the treating solution. Such discovery opens the opportunity to develop clinical procedures to perform diagnosis or treatments in the ultraviolet., L.O. and V.T. have contributed equally to this work. The work was supported by the Portuguese grant FCTUID/ EQU/04730/2013. V.T. was supported by RF Governmental grant 14.W03.31.0023.

Leaf biochemical constituents provide useful information about major ecological processes. As a fast and nondestructive method, remote sensing techniques are critical to reflect leaf biochemistry via models. PROSPECT model has been widely applied in retrieving leaf traits by providing hemispherical reflectance and transmittance. However, the process of measuring both reflectance and transmittance can be time-consuming and laborious. Contrary to use reflectance spectrum alone in PROSPECT model inversion, which has been adopted by many researchers, this study proposes to use transmission spectrum alone, with the increasing availability of the latter through various remote sensing techniques. Then we analyzed the performance of PROSPECT model inversion with (1) only transmission spectrum, (2) only reflectance and (3) both reflectance and transmittance, using synthetic datasets (with varying levels of random noise and systematic noise) and two experimental datasets (LOPEX and ANGERS). The results show that (1) PROSPECT-5 model inversion based solely on transmission spectrum is viable with results generally better than that based solely on reflectance spectrum; (2) leaf dry matter can be better estimated using only transmittance or reflectance than with both reflectance and transmittance spectra.

In this article experimental data are presented for inorganic gel based smart window fabricated using silica sol–gel process. Parallel beam transmittances were measured as functions of voltages for samples fabricated with different concentrations of nitric acid. Spectroscopic transmittance data at different driving voltages for samples fabricated with different LC concentrations are shown. Transmittance spectra of the Si–Ti based gel-based-liquid-crystal (GDLC) device measured as different driving voltages were compared with those of PDLC. GDLC showed much lower operating voltages, 10–15 V, for on-state. Formation of the LC droplet in gelation process is illustrated. The methyl organic group surrounds LC droplets. Demonstration of GDLC based smart window showed the successful operation with low driving voltages. GDLC window shows clear color, even at off-state, compared with PDLC.

Eu3+ doped heavy germanate scintillating glasses were prepared by melt quenching method. Their physical and luminescent properties were investigated. The glasses exhibit the densities of more than 6.5 g/cm3. The transmittance spectra show the glasses have good transmittance in the visible region. The glasses show intense red emissions under 393 nm light excitation and X-ray excitation. The lifetimes of 614 nm emission of Eu3+-doped germanate glasses are in the range from 1.424 ms to 1.484 ms. The results indicate that Eu3+-doped high density germanate scintillating glasses could be of good anti-radiation properties and could be an X-ray scintillating material suitable to X-ray detection for slow event.

The synthesis and characterization of peripherally ({1-[(Z or E)-phenylazo]-2-naphthyl} oxy) tetra-substituted metal-free and metallo (Zn(II), Co(II) and Cu(II)) phthalocyanines are described in this study. Aggregation properties of these compounds were investigated in the concentration range of 20–1 μM in tetrahydrofuran. Spectroscopic and photophysical properties of these phthalocyanines have been investigated in tetrahydrofuran. Thin films of metallophthalocyanines were prepared by spin coating technique. Results show that transmittance values of the films change with respect to the metal ions in the visible and Q absorptions regions. Films were also annealed at 100, 200 and 300 °C and their optical properties were investigated as a function of annealing temperature. The spectrophotometric measurements of transmittance spectra were carried out in the wavelength range 200–1000 nm. Results showed that transmittance values of ZnPc thin films were increased as a result of heat treatment.

SnO2 nanostructure thin films were deposited on glass substrate at 450 °C by chemical spray pyrolysis (CPS) technique and then annealed at different temperatures; 450, 550 and 650 °C for 1 h. X-ray diffractions (XRD) of samples showed that grain size of thin films grows gradually from 48 nm for (as prepared sample) to 55 nm (for annealed at 650 °C sample). Transmittance spectra indicated that with increasing the annealing temperature up to 550 °C the transmittance is considerably decreased from 90% to ∼83%, and then increases to 89% for the samples annealed at 650 °C. It is also found that the band gap is gradually decreases with increasing the annealing temperature. PL spectra are shown an intense and broad emission at 434 nm for as prepared sample and that annealed at 450 °C and 550 °C, and a weak broad peak for sample that annealed at 650 °C.

Based on the transmittance spectra modeling, spectroscopic methods were developed to determine the optical properties of a liquid paraffin-filled double glazing unit, including reflectance and absorptance. The transmittance spectrograms of paraffin-filled double glazing units at normal incidence with different thicknesses in the wavelength 240–900 nm were measured by a TU-19 FTIR spectrometer. These values were introduced into spectroscopic methods to calculate the reflectance and absorptance of paraffin-filled double glazing units. The results showed the transmittances of glazing unit that are filled with paraffin in most area are enhanced compared with the empty glazing unit. The absorption and reflectance profiles with different paraffin thicknesses are very similar in shape and are relevantly affected by the paraffin thickness.

In this study, a method for optical simulation of external quantum efficiency (EQE) spectra of solar cells based on spectroscopy is proposed, which is based on the tested transmittance and reflectance spectra. First, to obtain a more accurate information of refractive index and extinction coefficient values, we modified the reported optical constants from the measured reflectance and transmittance spectra. The obtained optical constants of each layer were then collected to simulate the EQE spectra of the device. This method provides a simple, accurate and versatile way to obtain the actual optical constants of different layers. The EQE simulation approach was applied to the flat and textured heterojunctions with intrinsic layers (HIT) solar cells, respectively, which showed a perfect matching between the calculation results and the experimental data. Furthermore, the specific optical losses in different devices were analyzed.

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.

An improved double-thickness method combined with genetic algorithm was developed to determine the optical constants of liquid hydrocarbon fuels. Different from traditional transmission measurement, it obtained the total transmittance of a window–liquid–window three-layer structure, which is the ratio of the transmission intensity of the filled cell and that of the empty sample compartment. Also, the change of the surface reflectance at the interface of the liquid sample and the optical window and the difference between forward reflection and back reflection are considered. Experiments were operated to measure spectra in the wavelength range of 0.83–2.2 µm using a Fourier transform infrared (FT-IR) spectrometer. To verify the reliability of this method, optical constants of the distilled water were determined from its experimental transmittance spectra and the results agreed well with published data. On the basis of verification, the transmittance spectra of Chinese No. -35 diesel fuel were measured at 300 K, 350 K, and 400 K with liquid sample thicknesses of 0.5 mm and 1.0 mm. Then the optical constants of the diesel sample were obtained and the temperature dependence was analyzed. Analytical results indicate that the biggest change of the extinction coefficient between 300 K and 400 K can reach 30%, while that of the refractive index is 4.7%.

This work presents the study of optical constants and film thickness of blended organic thin films, emphasizing on the modeling procedure with modified genetic algorithm aided by absorption or transmittance spectra of both pure materials and the blends. Taking the blending of copper phthalocyanine (CuPc) and fullerene (C60) as an example, a simple, convenient and low-cost method for the determination of the optical constants and film thickness of blended organic thin films was demonstrated. New scheme for optical modeling of blended organic thin film was proposed by introducing peak energies of Cody-Lorentz oscillators of the pure materials, which were determined by fitting the film absorption of pure materials. These oscillators of pure materials could be recognized in the transmittance spectrum of their blends, and were further used as the initial searching ranges in the simulation of blended films. As a result, the constraint bounds of the unknown parameters were significantly reduced and modeling efficiency as well as fitting accuracy was improved. For instance, the fitting of the transmittance curves of blended films with different blending ratios reached reliable results in comparison with extinction coefficients obtained from experiment.

We present the transmittance of two types of one-dimensional periodic structures. The first type of structure consists of alternating layers of a dielectric material. The second type of structure consists of alternating layers of a dielectric material and a superconductor whose dielectric properties are described by the two-fluid model. The variance of the intensity and the bandwidth of the transmittance are strongly dependent on the thicknesses, temperature, and frequencies. We have compared the transmittance spectra and present some details about the two types of structure. In the first type, we will make a comparison between the optical properties of the high temperature superconducting photonic crystal (HTScPC) by using the YBa2Cu3O7 as a superconductor layer with SrTiO3 as a dielectric layer. The second type consists of the dielectric photonic crystals (DPCs) and Al2O3 or MgO with SrTiO3 within the ultra-violet region. The comparison obtained according to the difference of the thickness of SrTiO3 and the variance of the number of periods. The common result is changed in the number of PBGs within the UV range.

Previous results revealed that the influences, caused by both individual differences an1d measuring environmental factors, would be reduced by using the floating-reference theory (FRT) for diffused reflectance spectra (DRS) -based blood glucose measurement by Near Infrared Spectroscopy (NIRS). The obtained signals could highlight the variation in light intensity which was brought only by the change of glucose concentration. The existing studies on FRT have mainly focused on the diffused reflectance spectra, but rarely involved the diffused transmittance spectra. In this talk, it is our aim to investigate the availability of FRT on the diffused transmittance spectra (DTS) on the basis of Monte Carlo (MC) simulation method. The MC simulations of DTS have been carried out with different glucose concentrations and skin tissue thicknesses. The simulation results show that the floating reference position point of DTS will disappear when the tissue thickness is greater than a certain value. Therefore, the FRT might be applied on thin tissue model for DTS by NIRS.

In this report, we have studied the compositional dependence of structural, optical and electrical properties of polycrystalline In x Ga1−x N thin films grown by modified activated reactive evaporation. The growth was monitored by optical emission spectroscopy. The thickness of the films was in the range ~600–800 nm. The phase, crystallinity and composition of the films were determined by X-ray diffraction, Raman spectroscopy and energy dispersive X-ray analysis. The surface morphology was studied by atomic force microscopy. The band gaps of these films obtained from transmittance and photoluminescence measurements were found to vary from 1.88 to 3.22 eV. All the films show n-type conductivity. The carrier concentration was found to be decreasing with increase in gallium incorporation which is in good agreement with the free carrier absorption observed in transmittance spectra.

Characteristic matrix method was used to calculate the transmittance spectra of the one-dimensional photonic crystals (1-D PCs). By theoretical calculations, the transmittance spectra of time-harmonic electromagnetic wave in the 1-D PCs with various incident angles were derived. From the transmittance spectra, it shown that along with the incident angle increased from 0o to 85o, the frequency range of stop band gap also increased from 0.085 to 0.119 for the certain periodicity N=16 of the 1-D PCs. In addition, for a certain incident angle (in this letter, the incident angle 30o was used), the transmittance spectra for different periodicity (N=2, 4, 8 and 16 respectively) were also calculated, it demonstrated that different incident angles could influence the stop band gap range markedly, but on the transmittance was minimal.

The transmittance spectra of one-dimensional photonic crystals (1-D PCs) with single defect in different location have been calculated. Defined the parameter N as the number of the layers located to the left of the single defect, set 13 as the number of the total layers of the 1-D PCs included the defect, during the course of the number of N increased from 0 to 12, as it upped to 3, there occurred defect band gap in the stop band gap, and when N upped to 12, the defect band gap disappeared; besides, the defect band gap is at frequencies between 0.3000~0.3090, most of them are at the frequencies around 0.3020. In addition, the transmittance has a turning point at the parameter N=7, that is to say, there has an approximate symmetry in transmittance when the parameter N increased from 3 to 11.

The time-harmonic electromagnetic wave through the one-dimensional photonic crystals (1-D PCs) perpendicularly has been considered. By theoretical calculation with characteristic matrix method, the dispersion curves and the transmittance spectra were calculated. From the dispersion curves, it shown that the lowest band gap is at frequencies between 0.23~0.32, i.e. it is around 0.27. In addition, according to the transmittance spectra, it shown that the transmittance declined from 40.6% to 0 dramatically along with the periodicity N of the periodically stratified medium increased from 2 to 1024, it also exhibited that when the periodicity N was upped to 8, it could form 1-D PCs.

A rigorous and consistent approach is demonstrated to develop a model of the 4M structure (the four-media structure of a film on a substrate of finite thickness). The general equations obtained for the reflectance and transmittance spectra of the 4M structure are simplified by employing a procedure of the so-called device averaging to reduce them to a succinct form convenient for processing of experimental spectra for the structures with a thick substrate. The newly derived equations are applied to two special cases: (i) an arbitrary film on highly absorbing substrates and (ii) a slightly absorbing film on transparent substrates. The reflectance and transmittance spectra represented in the simplified (with the device averaging) form have a practical application for determining the film thickness and optical constants from experimental spectra by using the known techniques.

We present the transmittance of two types of one-dimensional periodic structures as functions of the frequency of the electromagnetic field incident on them for different thicknesses of the layers from which they are formed. The first type of structure consists of alternating layers of a dielectric material and a lossy metal that is defined by the Drude model. The second type of structure consists of alternating layers of a dielectric material and a superconductor whose dielectric properties are described by the two-fluid model. The variance of the intensity and the bandwidth of the transmittance are strongly dependent on the thicknesses, temperature and frequencies. We have compared between the transmittance spectra and present some details about the two types of structure.

The goal of this study was to develop prediction models to estimate the storage days of tomato. The transmittance spectral data measured on tomato were preprocessed through normalization, SNV, Savitzky-Golay, and Norris Gap and then were used to build the prediction models using partial least square (PLS) method. For the experiments, the tomato samples of different varieties were collected at different harvest time. The samples were taken right after harvest from the field and then were stored in a low-temperature storage room in which room temperature was maintained at . The transmittance spectral data of the tomato samples were measured at three-day intervals for 16 days. The performance of the prediction models was affected by the preprocessing techniques as well as the varieties and harvest time of the tomato. The best model was found when SNV was applied. The accuracy of the best model was 90.2%. It can be concluded that the transmittance spectra are useful information for predicting the period of storage of tomato.

We have investigated the transmittance for two kinds of photonic crystals; (i) One-dimensional metallic photonic crystals (1DMPCs) and (ii) One-dimensional superconducting photonic crystals (1DScPCs). The variance of the intensity and the bandwidth of the transmittance are strongly dependent on the thicknesses and frequencies. We have compared the transmittance spectra in 1DScPCs and 1DMPCs at low frequencies, and we present some details about the transmittance spectra by using Transfer Matrix Method (TMM) at the same conditions.

A novel structure of photoelectrochromic cell fabricated with titanium wirelike photo-electrode is introduced in this paper. The transmittance spectra show that average transmittance of devices is 68.0% (from 400 to 1100 nm) at bleached state and 26.1% (from 400 to 1100 nm) at colored state, respectively. And the maximal photopic transmittance of the device varies from 81.9% (bleached state) to 30.3% (colored state) at 736 nm. Compared with traditional devices, the spectral response range is improved obviously, which solves the problem of lower transmittance at bleached state for traditional devices.

The transmittance spectra of a long-period fiber grating element immersed in different mixtures of water and dimethyl sulfoxide were recorded. The obtained data were compared with a theoretical model based on linearly polarized modes treated with a coupled-mode approach. Excellent agreement between the measurements and theoretical results was found over a wide wavelength range.

Magnesium oxide (MgO) single crystals with an average size of 6 cm have been grown by an arc-fusion method. X-ray powder diffraction and ultraviolet transmittance spectra are used to characterize properties of the obtained MgO single crystals. In addition, an efficient method for the proper use of three electrodes is applied to reduce the number of bubbles in the obtained MgO sample, which allows us to gain optically transparent high-purity MgO single crystals. Our present work shows that the control of the temperature field of the whole system is crucial to grow high-purity MgO single crystals with large and super-large sizes.

Staining of tissue specimens is a classical procedure in pathological diagnosis to enhance the contrast between tissue components such that identification and classification of these components can be easily performed. In this paper, a framework for digital staining of pathological specimens using the information derived from the L-band spectral transmittance of various pathological tissue components is introduced, particularly the transformation of a Hematoxylin and Eosin (HE) stained specimen to its Masson-Trichrome (MT) stained counterpart. The digital staining framework involves the classification of tissue components, which are highlighted when the specimen is actually stained with MT stain, e.g. fibrosis, from the HE-stained image; and the linear mapping between specific sets of HE and MT stained transmittance spectra through pseudo-inverse procedure to produce the LxL transformation matrices that will be used to transform the HE stained transmittance to its equivalent MT stained transmittance configuration. To generate the digitally stained image, the decisions of multiple quadratic classifiers are pooled to form the weighting factors for the transformation matrices. Initial results of our experiments on liver specimens show the viability of multispectral imaging (MSI) for the implementation of digital staining in the pathological context.

The infrared transmittance and Raman scattering spectra in TlGaS 2 , TlInS 2 and TlGaSe 2 layered singlecrystals grown by Bridgman method were studied in the frequency ranges of 400 –1500 and 10 400 cm −1 ,respectively. Three, three and five bands observed at room temperature in IR transmittance spectra ofTlGaS 2 , TlInS 2 and TlGaSe 2 , respectively, were interpreted in terms of multiphonon absorption processes.& 2013 Elsevier B.V. All rights reserved. 1. IntroductionTernary layered crystals TlGaS 2 , TlInS 2 and TlGaSe 2 are chemi-cal analogs of TlSe compounds [1,2]. The lattices consist of strictlyperiodic two-dimensional layers, each successive layer beingturned by a 901 angle about the normal of the previous one.Interlayer bonding is formed betweenTl and S(Se) atoms while theones between Ga(In) and S(Se) atoms are an intralayer bonding.High photosensitivity in the visible range of spectra, high birefrin-gence in conjunction with a wide transparency range of 0.5–14 μmmake these crystals useful for optoelectronic applications [3].Unit cells of TlGaS

To develop a more complete foundation for remote sensing of the marsh grass Juncus roemerianus, we measured the optical properties of its cylindrical leaves at sites of different canopy height, biomass composition and amount, and connectivity to ocean flushing. To measure the leaf optical properties, we adapted a technique used for conifer needles. After establishing the reliability and limits of the adapted technique to the wider J.roemerianus leaves, mean transmittance and reflectance spectra were compared to associated leaf diameters from two dates in 1999 and 2002 and at each site. Transmittance was inversely related to leaf diameter. Mean transmittance and reflectance generated from reoccupation of many field sites in 2002 indicated little or no difference in transmittance between years, a slight reflectance difference in the visible (

Sol–gel-derived materials can be exploited for the construction of various optoelectronic devices, including sensors optodes and their protective layers, as well as other kinds of coatings. Different types of materials were studied: silica sol–gel matrices made from silica solutions with water or alcohol as solvents. The samples were prepared in the form of single layer films. The films were deposited on glass surfaces. The porous structure of sol–gels layers was examined as well as the transmittance spectra, which were measured in the visible and UV regions. A strong influence of the solvent type on the material optical properties was noted. Alcohol-based samples showed stable homogenous structures, with no cracking. However, the water-based samples demonstrated higher transmittance in the visible region. The obtained results can serve as a basis for choosing a suitable layer when constructing optical sensors or coatings.

We have calculated the dependence of transmittance spectra with wavelength for TE wave at normal incidence in one-dimensional dielectric photonic crystals (1DPC) using the transfer matrix method. We demonstrate that when consider two defects layers spatial breaking periodicity in the 1DPC, the presence of defect modes located within the photonic band gap can be found. Additionally we have calculated the effect on the transmittance spectrum by varying the thickness of the defects in the 1DPC.

Infrared transmittance and electrical properties of undoped and In-doped CdTe single crystals were investigated before and after post-growth annealing at high temperature followed by various cooling regimes. Typical free carrier absorption was found in the IR transmittance spectra at low energies. Non-standard absorption behavior was observed in the range 0.8–1.5 eV in samples, which were quenched in the air after annealing.

The sol–gel-derived materials provide excellent matrices for a variety of organic and inorganic compounds. They can be exploited for the construction of various optoelectronic devices, including semiconductors or optodes of fiberoptic sensors. Different types of materials were studied: pure sol–gel matrices prepared on the way of acid hydrolysis, various doped matrices with embedded albumin, urease and osmium tetraoxide, as well as high-temperature treated sol–gel bulks. The transmittance spectra were measured in visible, as well as in UV region. The room temperature stored samples show the highest transmittance in both: visible and in UV spectrum, compared to the heated ones. The transmittances of heated matrices depend strongly on the heating temperature. The influence of the dopants on the matrices transmittance behavior is studied, as well.

Single fibres dyed by indigo and its seven derivatives were measured by microspectrophotometric examination of transmittance spectra in the ultraviolet-visible region (240-760 nm). Glycerin was the most suitable embedding reagent for this measurement. Small intra-sample variation of the transmittance intensity in single woollen fibres was observed, but relatively large inter-sample variation was observed among the fibres obtained from different areas in the same textile. There were no differences in the hmax, hmin and the position of shoulders observed in their spectra. This method was applied to the discrimination of single cotton fibres dyed by vat dyes, such as indigo and seven indigo derivatives which had similar structures. On the basis of the ultraviolet-visible transmittance spectra, these sample fibres could be distinguished from one another. It is a non-destructive method compared with chromatographic dyestuff extraction methods; furthermore, utilization of the ultraviolet region gave spectra providing useful information for evaluating fibre evidence.

OBJECTIVES To evaluate the ultraviolet (UV) transmittance spectra of different contact lenses and assess the effect of wear on UV transmittance values and ocular protection factor (PF). METHODS Transmittance in the UV range (200-400 nm) of 216 contact lenses was measured before and after wear, using a spectrophotometer. The contact lenses used were ACUVUE TruEye, ACUVUE MOIST, ACUVUE OASYS, ACUVUE 2, ACUVUE DEFINE, DAILIES AquaComfort Plus, AIR OPTIX for astigmatism, FreshLook ONE-DAY lens, and Neo Cosmo. RESULTS This study indicates that the following contact lenses transmitted less than the American National Standards Institute (ANSI) of 5% or less of UVB: ACUVUE DEFINE, ACUVUE MOIST, ACUVUE 2, ACUVUE TruEye, and ACUVUE OASYS. All lenses also met the ANSI standard of less than 30% transmittance of UVA except for AquaComfort Plus, AIR OPTIX for astigmatism, and Neo Cosmo. FreshLook meets the UVA transmission standard but fell short of the UVB transmission standard by 3%. FreshLook and ACUVUE MOIST had the highest calculated PF (3.9) of the hydrogel group and were unaffected after wear. Of the silicone-hydrogels (SiHs), the PF for AIR OPTIX for astigmatism was the highest (10.6) before wear and increased after wear to a PF of 13.3. The results also show that, for the UVC region, significant differences exist in transmittance values before and after wear of all SiH lenses and all hydrogel lenses, except for Neo Cosmo. FreshLook and Neo Cosmo were the only lenses that showed no statistically significant differences in the UVA transmittance after wear. CONCLUSIONS Ultraviolet-blocking contact lenses were effective in blocking ultraviolet radiation to safe levels recommended by ANSI, whereas non-UV blockers such as AquaComfort Plus and AIR OPTIX for astigmatism also showed UV-attenuation capabilities greater than the values previously reported. The Neo Cosmo contact lens transmitted greater than 86% UVB and 89% UVA, making it unsuitable for UV protection seekers. Transmission is modified after contact lens wear in almost all lenses but more so in the SiH lenses, probably because of the formation of biofilms on the lens surface.

The methods to grow a novel upconversion crystal Ba2ErCl7 are reported in this note. Ba2ErCl7 material was synthesized with Er2O3, BaCl2·2H2O and NH4Cl by using a so-called “direct synthesis method”. High quality Ba2ErCl7 single crystals with size up to 4 mm×8 mm×15 mm were grown by using the Czochralski and the Bridgman methods. Intense yellow-green luminescence was detected when the crystal was pumped by an 803 laser diode (LD). Transmittance spectrum was measured by using HITACH U-3500 spectrophotometer at room temperature for the first time, in which one can see that the transmittance is high in the range from 350 to 1 600 nm and the cut-off wavelength of the crystal was 230 nm. The upconversion mechanisms were discussed.

Sun care products containing sunscreens are widely used, but consumers are generally unaware of the important differences in the ability of these lotions to block exposure to the ultraviolet A (UVA) portion of the solar spectrum. The purpose of this study was to determine the transmittance spectra, with particular emphasis on the UVA portion of the spectrum, for a variety of commercially available sun care products, to determine Commission Internationale d'Eclairage (CIE) erythema effectiveness spectra and to compare these with information in the product label. The transmittance spectra for a sample of sun care products were measured spectrophotometrically. These values were convoluted with the CIE erythema action spectrum and the sunlight spectra determined for solar noon on June 21 at 0 degrees and 50 degrees N latitude to produce CIE effectiveness spectra. The UVA transmitted through the sun care products that claimed UVA protection on the bottle label varied from as little as 6% to as much as 52%. In addition, it was determined from the CIE effectiveness spectra that any erythema induced following application of the tested lotions would be caused by the UVA portion of the solar spectrum for all, but one, of the products examined. The results of this study emphasize the necessity for better guidance to the consumer as to the ability of sun care products to provide protection against UVA exposure.

The concept of using commercially available water fog generators to simulate natural fogs and military obscurants is investigated. Results obtained with a high-pressure direct impaction system developed for agricultural and environmental control applications are reported. Experiments verify that such systems can produce optically dense “artificial fogs” similar in appearance to natural fogs under favorable meteorological conditions. Measurements of the droplet mass distribution function indicate a broad spectrum in the lower size region (0.3–1.5 μm) and a marked peak in the upper region at a diameter of about 17 μm. Experiments show that droplet size can be partially controlled with common surfactants and inhibitors. The artificially generated fogs are good broadband obscurants, exhibiting a nearly flat transmittance spectrum in the visible through mid-infrared regions with a broad peak in the far infrared region. The measured extinction spectrum is similar to natural fogs, being in between the advective and radiative cases.

In ophthalmology the research using "in vitro" corneas are an excellent model for studies of new ophthalmologic procedures, enabling the analysis of effectiveness, performance and even safety parameters of the procedure. In this work we studied four "in vitro" human corneas preserved in OPTISOL-GS, with initial average pachymetry of 542 microns and a post-mortem average of 6 days. The corneas were preserved in OPTISOL-GS and were washed with saline solution to remove the excess the preservative medium. The corneas were placed in a device aligned with an ultraviolet source of 3mw/cm2 and an optical fiber positioned after the device near the endothelium of the cornea. The UV transmittance spectra in the region of 360-370nm were captured by the emission of UV source for 3 seconds. These spectra were captured every 5 minutes in a total of 60 minutes, resulting in 13 spectra per cornea. The measured average initial UV transmittance was 73% and after 50 minutes of dehydration there was no significant difference in the corneal teansmittance properties. However, for the last 10 minutes we have observed a decrease in the UV transmittance of 4%, probably indicated by corneal dehydration and swelling (wrinkling of the cornea tissue. The final average pachymetry was 421 microns and the UV transmittance after the 60 minutes was 69%. Therefore we can suppose that the UV transmittance of corneas "in vitro" is invariant over a period of up to 60 minutes, even with the thickness decrease, since the material that absorbs in the UV region remains intact and only water loss occurs.

As one of the most important ingredients of our diet, onion is the second largest fresh vegetable in the U.S. To meet the increasing quality demand of consumers, modern optical techniques like hyperspectral imaging have been investigated to evaluate onion quality nondestructively. To better apply these techniques, the optical properties of the dry skin and the flesh of healthy and sour skin infected onions were measured in the wavelength range of 450-1000 nm. The total diffuse reflectance, total transmittance, and collimated transmittance spectra of onion tissues were collected by using an integrating sphere system with a VIS-NIR spectrometer. The absorption coefficient (µa), reduced scattering coefficient (µ’s), and anisotropy (g) of the onion tissues were calculated using the inverse adding-doubling method based on the measured spectra. The results showed that both onion dry skin and flesh were scattering dominated biological tissues. The estimated µa and µ’s values of onion dry skins and flesh were comparable to the optical properties of other fruits and vegetables reported in the literature. In the Vis-NIR range, the µa and µ’s of the flesh of sour skin-infected onions were significantly different from those of the healthy onions, which proved the possibility to inspect quality of onion flesh by optical techniques. The results also suggested that onion dry skins should be handled properly in optical measurements since they can significantly affect the light propagation. The results of this study can be used to develop appropriate optical techniques to improve quality control of onions.

An NIR hardness score based on the reflectance of ground wheat is available (AACC Method 39–70A). However, it is desirable to derive an analogous score applicable to whole wheat so that an on-line measurement of hardness could be used in wheat blending. The intention was to use an algorithm based on the multiplicative effect of scatter on NIR spectra and so an experiment was carried out to determine whether or not the effect of scatter on reflectance and transmittance spectra of whole grain is multiplicative. As no evidence was found to support this model, a different approach will be needed. However, these studies have brought a new insight into the effect of scatter on the NIR spectra of whole grain.

We have investigated optical properties of thermally grown SiO2 layers within the thickness range 150 to 500 nm. The complex dielectric constant ε(ν˜) can be represented by six Lorentz-Gauss oscillators, which allow us to determine the optical constants of SiO2 films by fitting IR transmittance spectra. The spectra of ε(ν˜), unlike transmittance, are not affected by the multiple reflections at the film/air and film/substrate interfaces. Changes of optical constants for different thicknesses can be attributed to changes of physical properties of the film. We compare dielectric functions of samples oxidized at different conditions and discuss the influence of thickness and surface preparation of the substrate. We also compare our results with the dielectric function of bulk vitreous silica.

The Pt films with mass thicknesses ranging from 0.8 to 4.7 nm were evaporated onto quartz-glass substrates under vacuum conditions (p~10 -4 Pa) with evaporation rate ~0.01÷0.2 nm/s. Transmittance spectra were measured in the wavelength range from 196 to 2500 nm. The microstructures were examined by electron microscope. The films with low coverage coefficient consist of islands regular in shape, they prevail in the structure. With coverage coefficient increase the islands become more irregular and join one with other. The experimental and calculated histogram are presented. It has been found that for the films examined the dependencies of transmittance on wavelength exhibit the minima which shift to longer wavelengths with coverage coefficient increase. These optical properties are typical for the island films. The structural examinations confirm island structures of the films examined.

The spectral complex optical constants in the visible and the near-infrared region of VO(2) and V(1-x)W(x)O(2) films deposited on glass substrates were determined from observed reflectance and transmittance spectra for which the least-squares method was used. In the metallic phase, the optical properties were characterized by the Drude model in wavelength regions longer than 750 nm.

A biochemistry nanosensor based on hybrid metallic nanostructure array was put forward in this paper. The hybrid metallic nanostructure array consists of two types Ag nanostuctures, spherical and pyramidal structures with the same period. A biochemistry sensor experiment is demonstrated by detecting the transmittance spectra of hybrid metallic nanostructure using Sciencetech spectrophotometer. The wave peaks of transmittance spectra have shifts when the metallic periods and the refractive index of Ag nanostuctures are different.

This study explored the feasibility of near-infrared (NIR) quantitative and qualitative models for soybean inorganic phosphorus (Pi), which is complementary to phytic acid, a component of nutritional and environmental importance. Spectra, consisting of diffuse reflectance (1100-2500 nm) of ground meal and single-bean transmittance (600-1900 nm) of whole seed, were collected on 191 recombinant inbred soybean lines. Partial least-squares regression models were individually developed for soy meal diffuse reflectance, single-bean transmittance, and averaged (24 beans/line) whole seed transmittance data. The best performance was obtained with diffuse reflectance data, in which the standard errors (rmsd) were 263 and 248 mg/kg for cross-validation and validation sets, respectively. Model accuracy was lower for the 24-bean average transmittance spectra and still lower for single beans. Despite the overall poorer modeling ability of Pi with respect to the common macronutrient NIR regressions, such as those for protein and oil, this technique holds promise for use in breeding programs.

Internal product quality is an important aspect in the quality control and assurance of pickled products. A rapid and non-destructive method for internal defect detection would be of value to the pickling cucumber industry. A hyperspectral transmittance imaging technique was developed to detect internal mechanical injury in the form of carpel suture separation or hollow cucumbers. Partial least squares discriminant analysis (PLS-DA) and hyperspectral image thresholding methods were used to classify cucumber samples into defective or normal classes. Transmittance spectra of defective and normal cucumbers were similar in shape but higher in magnitude for the defective cucumbers. Transmittance values for both defective and normal cucumbers were higher in the nearinfrared range of 700-950 nm than that of the visible range (450-700nm). The hyperspectral image thresholding method resulted in higher classification accuracies compared to PLS-DA. An overall classification accuracy up to 94.3% percent was achieved. The hyperspectral transmittance imaging technique has the potential for rapid detection of internal mechanical injury in pickling cucumbers.

The principle of the ultraviolet and visible (UV-VIS) transmittance method to detect the quality of intact poultry egg and the characteristic of the transmittance spectra of the eggshell, egg content and intact egg were investigated in the spectra range of 200-800 nm using UV-VIS (UV-1100 nm)spectrophotometer at the air condition of 28±2°C and less than 55% R. H. The results indicated that eggshell thickness, different testing position and surface color of the eggshell influenced on spectroscopic characteristic of poultry eggs at a certain extent. There was obvious difference about transmittance spectra between the fertilized and non-fertilized eggs’ content. Two wave crests about 610 nm and 710 nm, and one wave trough about 650 nm in the spectral wavelength range of 500-760 nm were found in this research. A relationship between the intact egg transmittance and the storage time was developed and the correlation equation was established by linear regression analysis of SPSS10.0 with the correlation coefficients was 0.935 based on the sensitive spectral wavelength at the sensitive wavelength of 465 nm. There was significance at the α=0.01 level between the transmittance and the different storage time.

We report the quantitative fluorimetric estimation of the concentration of NADH in human blood samples. To measure both free and bound NADH, the 340-nm-excited fluorescence spectra was recorded from blood samples to which SDS was added. Diffuse reflectance and the transmittance spectra of the same sample were also recorded over the wavelength range 340-650 nm. These measurements were used to correct the measured fluorescence spectra for the wavelength-dependent reduction in fluorescence due to absorption and scattering in the blood sample. NADH concentrations estimated using the corrected fluorescence spectra were found to be in reasonable agreement with the concentrations estimated by the biochemical method.

Transparent and colorless lead fluoride crystals with sizes of 20 × 20 × 20 (mm3) are irradiated with several doses of γ-rays from a 60 Co source. Their transmittance spectra before and after irradiation are measured, and a new parameter ΔT = Tb − Ta is defined to evaluate the irradiation damage. Three optical absorption bands peaking at 270 nm, 370 nm and 500 nm are found in the plots of ΔT versus wavelength, and their intensities increase with the irradiation dose. These optical absorption bands, except the one at 270 nm, can recover spontaneously with time. Thermal annealing treatment can enhance this recovery of the transmittance, while the optimum annealing temperature for different samples depends on the irradiation dose.