Patent ID: 6278482
Filing Date: 2001-08-21
Classification: G02B

Abstract:
A method for manufacturing a planer lens having a single layer in a substantially plane shape, a plurality of transparent spheres being held in an adhesive layer, which includes the step of pressing said plurality of transparent spheres dispersed on the adhesive layer by a pressure means so as to embed said plurality of transparent spheres in the adhesive layer, comprising the steps of:detecting peak points of brightness from image data obtained by photographing while illuminating said transparent spheres so that a peak point of brightness brighter than the outside area of each sphere is formed in the inside area thereof and a low brightness area darker than the outside area is formed in the circumferential portion thereof;using a first predetermined value lower than the brightness level of the outside area of said each sphere and higher than the brightness level of said low brightness area in the circumferential portion of said each sphere in said image data, successively painting adjacent pixels having brightness of said first proper value or greater with each of the peak points of brightness detected by said brightness peak point detecting means as a starting point;binarizing said image data painted in a predetermined area by using a second predetermined value between said first predetermined value and the brightness level of the outside area of said each sphere as a threshold value;measuring a space filling percentage of said plurality of transparent spheres from the number of white or black pixels of the obtained binary image of said image data; anddetermining or controlling the disposition of said plurality of transparent spheres based on the measured space filling percentage.