Online backlight unit tester based on area CCD

Concept of using charge coupled device camera embedded with a calibrated image-processing algorithm as a two-dimensional luminance meter was successfully realized and verified with a small-scale backlight unit tester. This built apparatus takes only 3 seconds to get data of 10,000 points spreading uniformly in a 4-inches target, with target arbitrarily oriented. These merits make the tester more attractive and suitable for an online measurement system than other BLU testers based on area CCD.