Method And Device Of Measuring Focus Of Liquid Crystal Display And Cathode-Ray Tube

摘要

PURPOSE: An apparatus and a method for measuring focuses of a cathode ray tube and an LCD projector are provided to measure correctly focuses of a monitor and a screen by using only one camera for scanning various focus measuring points. CONSTITUTION: A pattern generation portion(102) is used for applying a pattern signal including a multitude of character, a multitude of crossed straight line, and a multitude of diagonal line to a cathode ray tube monitor(101). The cathode ray tube monitor(101) is used for displaying the pattern signal of the pattern generation portion(102). An image input portion(103) has a camera(103a) and a lens(103b) in order to photograph an image region of a pattern image displayed on the cathode ray tube(101). An image display process portion(104) is used for differentiating a pattern image signal(105) and determining a state of focus.