Melanopic dose rate and dose are calculated in a virtual environment. A computer generated model of an actual or planned building is used as the virtual environment. Indirect and direct spherical irradiances are calculated using convex polyhedra throughout the virtual environment, and each is multiplied by a melanopic conversion factor. The two are added, then adjusted for a human's angular responsivity and age. Building design features or lighting devices may be adjusted to provide a required melanopic dose rate. A camera is used to capture a panoramic image, which is calibrated to tristimulus values, and used with the spectral power distribution of the light sources to derive the melanopic dose rate.

A hyperspectral imaging spectrophotometer and system, with calibration, data collection, and image processing methods designed to match human visual perception and color matching of complex colored objects.

Provided is a lighting device that emits light of a color that approximates the color of the surface of an object or the like. Disclosed is a method for manufacturing a lighting device, including the steps of: spectroscopically measuring a spectrum that constitutes a color of a measurement target; and adjusting a color of a light source such that an emission spectrum approximates the spectrum that constitutes the color of the measurement target.

Disclosed is a method and system for cost effective, convenient remote color reproduction and matching that can be used to convey color to observers remote to the physical source of color. Such remote observers can include product consumers wishing to view a product color, for example. In a preferred embodiment, the method comprises capture of article or product reflectance spectra and the use of this spectrum to filter ambient light or directed light in the environment of a remote user. Other embodiments of methods include various techniques to capture product spectral information and color matching functions useful for color reproduction using colored light sources. Additional systems embodiments include devices exploiting multiprimary displays to render the product color in avoidance of metamerism.

Described herein is a process for correcting an observed color difference between a color at a first gloss and the color at a second gloss different than the first gloss, said process comprising the steps of: (a) determining a first correction caused by a lightness (Y-value) of the color a first gloss; (b) determining a second correction caused by an inclusion of a first surface diffusion in gloss readings; (c) based on the first and second corrections, determining a specular correction caused by a difference in specular reflections from the color at the first gloss and the color at the second gloss; (d) determining tristimulus corrections based on the specular correction; (e) preparing corrected tristimulus values of the color at a second gloss; and (f) producing a paint composition for the color at the second gloss using the corrected tristimulus values.

A method includes determining a fielded color measurement instrument is not calibrated to measure light emitted by a fielded light emitting device, assembling a calibration matrix, such that a product of the calibration matrix multiplied by a response of the fielded color measurement instrument to the light emitted by the fielded light emitting device is a triplet that corresponds to a Commission Internationale de L'éclairage XYZ color space, wherein the calibration matrix contains measurements made by the fielded color measurement instrument of a first plurality of lights emitted by the fielded light emitting device and measurements made by a spectroradiometer of a second plurality of lights emitted by a reference light emitting device of a same make and model as the fielded light emitting device, wherein the spectroradiometer is located remotely from the fielded color measurement instrument, and storing the calibration matrix on the fielded color measurement instrument.

A compact spectroradiometric device with a digital data processing system used to determine the spectral irradiance, illuminance, chromaticity, correlated color temperature, color rendering, flicker, equivalent melanopic lux and other characteristics of a light source as well as those same characteristics as observed in the transmittance through or reflectance from a sample being illuminated by that light source is described.

The invention generally relates to optical filters that provide regulation and/or enhancement of chromatic and luminous aspects of the color appearance of light to human vision, generally to applications of such optical filters, to therapeutic applications of such optical filters, to industrial and safety applications of such optical filters when incorporated, for example, in radiation-protective eyewear, to methods of designing such optical filters, to methods of manufacturing such optical filters, and to designs and methods of incorporating such optical filters into apparatus including, for example, eyewear and illuminants.

A vision inspection apparatus includes an inspection controller which displays a grid pattern with a plurality of gray levels on a display panel, an imaging converter which drives a charge-coupled device with a predetermined or set exposure-time and converts the grid pattern displayed on the display panel into a grid pattern signal, a charge calculator which calculates a charge amount per unit time for each color of a reference gray level using a reference gray level signal, included in the grid pattern signal, and the set exposure-time, and an exposure-time calculator which calculates an optimum exposure-time for each color of the reference gray level based on a target charge amount of the reference gray level.

There is disclosed a security device, including a substrate; a first color-shifting pigment on a first region of the substrate; and a second pigment, including at least three dielectric layers, on a second region of the substrate; wherein the first color-shifting pigment and the second pigment color match at a first viewing angle. Methods of making and using the security device are also disclosed.