Patent ID: 6974941
Filing Date: 2005-12-13
Classification: G01J

Abstract:
1. A light source testing method comprising: providing a light source for generating light; using an image capturing apparatus for capturing an image with a plurality of pixels according to the light, the image having an image center and an image edge at a distance of D selecting a predetermined gray level G, and defining a brightest area and the light source center as follows: defining the distance between the light source center c and the image center b as D calculating the area Q′ of the brightest area; calculating a maximum gray level GX of the plurality of pixels of the image, and a gray level difference h′=GX−G between the predetermined gray level G and the maximum gray level GX; calculating a product V′=h′*Q′ of the gray level difference h′ and the area Q′; calculating a plurality of rectangles surrounding the brightest area with their four sides in contact with the brightest area; selecting a specific rectangle having a minimum area among the plurality of rectangles, and defining the shorter side of the selected rectangle as X, the longer side as Y; defining the ratio of side R calculating the average gray level I according to the plurality of gray levels of the plurality of pixels; and evaluating the brightness and uniformity of the light source by calculating a P value as follows;