Patent ID: 9488518
Filing Date: 2016-11-08
CPC Classification: G01J,G09G

Claim Text:
1. A brightness calculating apparatus that calculates brightness at a calculation target position on an emission surface when light is emitted from a plurality of light sources of a light source unit, the brightness calculating apparatus comprising: a storage unit configured to store a plurality of attenuation coefficients corresponding to the calculation target position, for the plurality of light sources; and a processor programmed to function as a device that comprises: a setting unit configured to set a calculation target position on the emission surface; a sectioning unit configured to section the plurality of light sources into a plurality of sectioned regions in accordance with the calculation target position set by the setting unit; and a calculating unit configured to calculate the brightness at the calculation target position when light is emitted from the plurality of light sources by calculating, for each of the sectioned regions, the brightness at the calculation target position due to one or more light sources in each of the sectioned regions and summing up calculation results of the respective sectioned regions, wherein the sectioning unit sections light sources inside of a predetermined range from the calculation target position into a plurality of first sectioned regions respectively including a single light source, and sections light sources outside of the predetermined range from the calculation target position into one or more second sectioned regions respectively including two or more light sources, for each of the plurality of first sectioned regions, the calculating unit calculates the brightness at the calculation target position by using the attenuation coefficient of a single light source of each of the plurality of first sectioned regions as an attenuation coefficient of each of the plurality of first sectioned regions, and for each second sectioned region, the calculating unit calculates the brightness at the calculation target position by using a representative value of attenuation coefficients of the two or more light sources of each second sectioned region as an attenuation coefficient of each second sectioned region.