Patent ID: 6018361
Filing Date: 2000-01-25
Classification: H04N

Abstract:
An apparatus for measuring image qualities of a color display unit, comprising:an image quality sensor comprising a color video camera for imaging a display screen of the color display unit and a fixed-focus lens combined as an imaging lens with said color video camera;image quality measuring means for measuring image qualities of the color display unit based on an image signal generated by said color video camera; andimage signal generating means for generating an image signal required to measure the image qualities and supplying the image signal to the color display unit;wherein said color display unit either comprises a color cathode-ray tube or includes a color cathode-ray tube, further comprising magnetic field generating means for imparting an external magnetic field to electron beams in said color cathode-ray tube; andwherein said magnetic field generating means comprises a coil and staircase signal generating means for supplying a staircase current to said coil.