34 results about "Diffuse transmittance" patented technology

A device and a method to provide a more reliable and accurate measurement of hematocrit (Hct) by noninvasive means. The changes in the intensities of light of multiple wavelengths transmitted through or reflected light from the tissue location are recorded immediately before and after occluding the flow of venous blood from the tissue location with an occlusion device positioned near the tissue location. As the venous return stops and the incoming arterial blood expands the blood vessels, the light intensities measured within a particular band of near-infrared wavelengths decrease in proportion to the volume of hemoglobin in the tissue location; those intensities measured within a separate band of wavelengths in which water absorbs respond to the difference between the water fractions within the blood and the displaced tissue volume. A mathematical algorithm applied to the time-varying intensities yields a quantitative estimate of the absolute concentration of hemoglobin in the blood. To compensate for the effect of the unknown fraction of water in the extravascular tissue on the Hct measurement, the tissue water fraction is determined before the occlusion cycle begins by measuring the diffuse transmittance or reflectance spectra of the tissue at selected wavelengths.

The present invention provides a diffusely-reflecting polarizer havinga first polymer which is amorphous and having a birefringence of less than about 0.02 and a second polymer, the first polymer being a continuous phase, and the second polymer being a disperse phase whose index of refraction differs from said continuous phase by greater than about 0.05 along a first axis and by less than about 0.05 along a second axis orthogonal to said first axis;wherein the diffuse-reflectivity of said first and second polymers taken together along at least one axis for at least one polarization state of electromagnetic radiation is at least about 50%, the diffuse transmittance of said first and second polymers taken together along at least one axis for at least one polarization state of electromagnetic radiation is at least about 50%.

A nitride semiconductor light-emitting device includes a nitride semiconductor light-emitting chip including an active layer for outputting polarized light, the active layer having a non-polar plane or a semi-polar plane as a growth plane; and a light-transmissive cover for transmitting light from the active layer. The light-transmissive cover includes a first light-transmissive member located in an area, among areas to the side of the nitride semiconductor light-emitting chip, and in a direction perpendicular to a polarization direction of the polarized light, and a second light-transmissive member located in an area above the nitride semiconductor light-emitting chip. The first light-transmissive member has a higher diffuse transmittance than the second light-transmissive member.

Method and apparatus for spectrophotometric characterization of turbid materials are provided. An incident light beam is used to illuminate a turbid material sample and optical signals of coherent reflectance, diffuse reflectance, collimated transmittance and diffuse transmittance are measured from the sample as functions of wavelength. The following optical parameters are determined as functions of wavelength for spectrophotometric characterization of the turbid material sample in the spectrum of interest: absorption coefficients μa, scattering coefficient μs, anisotropy factor g and real refractive index n.

A diffuser is formed on an inner surface of a globe included in a compact self-ballasted fluorescent lamp, and a diffuse transmittance of the diffuser τ is set at 95%. When designing dimensions of the compact self-ballasted fluorescent lamp, at the same time, a ratio Dg / Pg is set at 0.8 or greater. Here, Pg is a helical pitch of an arc tube having a helical configuration, and Dg is a half of a difference between a helix diameter of the arc tube and a maximum outside diameter of the globe.

The disclosure relates to optical measuring methods and apparatus for determining the transmission and / or reflection properties of translucent objects with utility for process monitoring and quality inspection in the manufacture of surface-coated substrates. According to the disclosure the transmission and reflection properties are determined in such a way that sequentially:a first large surface of the object is illuminated by a first illuminating device, with a photodetector measuring the total transmittance (Ttotal),a second, large surface of the object, lying opposite and parallel to the first one, is illuminated by a second illuminating device, with a photodetector measuring the diffuse transmittance (Tdiffuse), and optionallythe first large surface of the object is illuminated by the first illuminating device, with the photodetector measuring the reflectance, and / orthe second large surface of the object is illuminated by the second illuminating device,with the photodetector measuring the reflectance.

The present invention provides a method for manufacturing a diffusely reflecting polarizer, comprising the steps of: coextruding first and second polymers through a chaotic mixer and a sheeting die to produce a cast sheet with a desired blend morphology and stretching said cast sheet to produce a composite film containing a first polymer having a birefringence of less than 0.02, with said first polymer being an amorphous material and a continuous phase, and a second polymer which forms a dispersed phase, and having an index of refraction that differs from said continuous phase by greater than about 0.05 along a first axis and by less than about 0.05 along a second axis orthogonal to said first axis, wherein said first and second polymers taken together along a first axis for one polarization state of electromagnetic radiation exhibit a diffuse reflectivity R 1d , a specular reflectivity R 1s , a total reflectivity R 1t , a diffuse transmittance T 1d , a specular transmittance T 1s , and a total transmittance T 1t , and along a second axis for another polarization state of electromagnetic radiation exhibit a diffuse reflectivity R 2d , a specular reflectivity R 2s , a total reflectivity R 2t , a diffuse transmittance T 2d , a specular transmittance T 2s , and a total transmittance T 2t , the said first and second axes being orthogonal, wherein the parameters of composition, chaotic mixing, stretch temperature and stretch ratio for the process and Tg, and refractive index of the first and second polymers are selected to satisfy the equations: R 1 d is greater than R 1 s ; T 2 t / 1 - 0.5 R 1 t + R 2 t > 1.35.

The present invention provides a method for manufacturing a diffusely reflecting polarizer, comprising: extruding and stretching a film containing a first polymer having a birefringence of less than 0.02, with said first polymer being a substantially amorphous nano-composite material, and a second polymer, the first polymer being a major phase, and the second polymer being a dispersed minor phase, wherein said first and second polymers taken together along a first axis for one polarization state of electromagnetic radiation exhibit a diffuse reflectivity R 1d , a specular reflectivity R 1s , a total reflectivity R 1t , a diffuse transmittance T 1d , a specular transmittance T 1s , and a total transmittance T 1t, and along a second axis for another polarization state of electromagnetic radiation exhibit a diffuse reflectivity R 2d , a specular reflectivity R 2s , a total reflectivity R 2t , a diffuse transmittance T 2d , a specular transmittance T 2s , and a total transmittance T 2t , the said first and second axes being orthogonal, wherein the parameters of composition, Tg, and refractive index and the stretch temperature and stretch ratio of the first and second polymers are selected to satisfy the equations: (1) R 1d is greater than R 1s ; and (2) T 2 t / ( 1 - 0.5 ( R 1 t + R 2 t) )> 1.35.

The present invention provides a method for manufacturing a diffusely reflecting polarizer, comprising the steps of: coextruding first and second polymers through a chaotic mixer and a sheeting die to produce a cast sheet with a desired blend morphology and stretching said cast sheet to produce a composite film containing a first polymer having a birefringence of less than 0.02, with said first polymer being a substantially amorphous nano-composite material, and a second polymer, the first polymer being a major phase, and the second polymer being a dispersed minor phase, wherein said first and second polymers taken together along a first axis for one polarization state of electromagnetic radiation exhibit a diffuse reflectivity R 1d , a specular reflectivity R 1s , a total reflectivity R 1t , a diffuse transmittance T 1d , a specular transmittance T 1s , and a total transmittance T 1t , and along a second axis for another polarization state of electromagnetic radiation exhibit a diffuse reflectivity R 2d , a specular reflectivity R 2s , a total reflectivity R 2t , a diffuse transmittance T 2d , a specular transmittance T 2s , and a total transmittance T 2t , the said first and second axes being orthogonal, wherein the parameters of composition, chaotic mixing, stretch temperature, stretch ratio for the process and Tg, and refractive index of the first and second polymers are selected to satisfy the equations: (1) R 1d is greater than R 1s ; and (2) T 2t / (1-0.5(R 1t +R 2t ))>1.35.

The invention discloses a class-II water atmospheric correction method based on neural network quadratic optimization and relates to the technical field of remote sensing image data processing. The method comprises the steps of extracting geometric information and wavelength information of an acquired hyperspectral image and an initial optical thickness value T(550)<0> of aerosol at 550nm; inputting the extracted parameters into a neutral network model, and outputting atmospheric transmittance t and total contribution Rho(path) in a simulation manner; simulating apparent reflectance Rho(toa)<sim> according to off-water reflectance Rho(w)(NIR) of a near infrared band together with the t and the Rho(path); performing spectral optimization on the Rho(toa)<sim> and real apparent reflectance Rho(toa)<mes> extracted from the image to finally obtain optimal solutions T(550)<pt>, R<opt> and n<opt>; inputting the T(550)<pt> into the neutral network model to obtain atmospheric diffuse transmittance t<opt> of all hyperspectral bands and the total contribution Rho(path)<opt> of atmospheric molecules and the aersol; estimating the off-water reflectance of the hyperspectral image according to the real apparent reflectance Rho(toa)<mes> of the image. According to the class-II water atmospheric correction method based on the neural network quadratic optimization, the practicability of the model is improved, the input parameters are reduced, and the estimation precision is improved.

An inexpensive substrate for thin film solar cells having improved performance of a thin film solar cell, and a manufacturing method thereof are provided by increasing light trapping effect due to effective increase in unevenness of a substrate for thin film solar cells. Furthermore, a thin film solar cell having improved performance using the substrate is provided. A substrate for thin film solar cells of the present invention has a transparent insulating substrate and a transparent electrode layer deposited thereon including at least zinc oxide (ZnO), the transparent insulating substrate has a fine surface unevenness having a root-mean-square deviation of the surface (RMS) 5 to 50 nm in an interface by a side of the transparent electrode layer, a projected area thereof consists of a curved surface, and furthermore a haze ratio or a ratio of a diffuse transmittance to a total transmittance as an index of unevenness of a substrate may be set at not less than 20% measured using a C light source. And thereby light trapping effect may effectively occur to improve performance of the thin film solar cell.

The invention provides a satellite atmospheric correction method for a multi-angle polarized water color remote sensor. The atmospheric correction method provided by the present invention uses the vector radiation transfer model to construct an index lookup table of atmospheric diffuse transmittance for the linear polarization component of the water-leaving radiation in the water body with medium and low turbidity. After accurate correction, the concentration of suspended particulate matter in water and the distribution of aerosol optical depth, concentration and particle size were obtained accurately according to the linear polarization component of water-leaving radiation. Through the atmospheric correction method provided by the present invention, the image quality of satellite remote sensing detection can be higher, and the detection result is more accurate.