LUMINANCE CORRECTING DEVICE OF ILLUMINANT FACE

摘要

PURPOSE:To attain fine luminance correction by storing a characteristics of uneven luminance on a fluorescent screen in a memory in advance. CONSTITUTION:When a picture synchronizing signal (a signal to synchronize a picture signal with an irradiated position of electron beam on a fluorescent screen of a CRT3a) is inputted to a counter 13, an output from the counter 13 is inputted to an address of a memory 14. All the uneven luminance of the CRT 3a is stored in the memory 14 and when the memory 14 is addressed by an output of the counter 13, the uneven luminance information of the addressed location is outputted in parallel and this output is inputted to a latch 15. The output of the latch 14 is D/A-converted 16 and analog luminance correcting signal is obtained and it is amplified 17 and then fed to a grid (g) of the CRT3a. The grid voltage (g) of the CRT3a is changed based on the information of uneven luminance of the memory 14 storing the entire illuminant face, the electron beam amount irradiated onto the fluorescent screen is controlled so as to eliminate almost the uneven luminance of the illuminant face.