公开(公告)号：JPH06125511A

公开(公告)日：1994-05-06

申请号：JP12312391

申请日：1991-04-26

Applicant: ALLIANT TECHSYSTEMS INC

Inventor： KERII ERU SHIEIKURII ,  TOOMASU EI SUTAAMU ,  JIYON SHII UITSUTENBAAGAA

IPC: G09G1/00 ,  H04N1/40 ,  H04N5/57 ,  H04N5/59 ,  H04N17/04

Abstract: PURPOSE: To compensate drift and to always secure high quality reproduction by detecting luminance changes that are caused by drift in video which occurs due to a temperature change and a change with the passage of time, changing voltage that is added to a 2nd grid and controlling video luminance to a pre scribed value. CONSTITUTION: A counting amplifier 110 outputs an output that corresponds to a cathode current IK from electric potential of a detection resistance 86, and an A/D converter 120 converts the output and adds it to a microcomputer(MC) 124. The MC 124 performs various arithmetic calculations and controls and decides the voltage of a 1st grid 74 and a cathode 72 through a control register 128, and amplifiers 132 and 136 with 1st and 2nd outputs. At the same time, after a D/A converter 158 has converted a 3rd output from the MC 124, an amplifier 160 amplifies it and supplies an appropriate bias signal to a 2nd grid 76. Through this, video luminance is controlled to a prescribed value, a drift that is caused by the temperature change and the change with the passage of time is compensated, and high quality reproduction is always secured.

公开(公告)号：JPH06133333A

公开(公告)日：1994-05-13

申请号：JP12459191

申请日：1991-04-30

Applicant: ALLIANT TECHSYSTEMS INC

Inventor： JIYON SHII UITSUTENBAAGAA ,  KERII ERU SHIEIKURII

IPC: B41J2/525 ,  H04N1/407 ,  H04N1/60 ,  H04N9/79

Abstract: PURPOSE: To make accurate high-resolution color reproduction possible by providing a shadow test pattern for color and correcting a signal indicating the color of a color recorder by comparing a signal indicating the reference shadow of the pattern with a signal indicating a recorded actual shadow. CONSTITUTION: A test pattern video is generated on a CRT 22 by generating one set of test pattern signals indicating the plurality of shadows of a color and a recording medium 12 is exposed to the video. When the test pattern is developed on the medium 12, a photodetector 52 detects signals respectively indicating an unexposed background and the luminance of each shadow of each color and supplies the signals to a microcomputer 70. Then one set of measured reflectance values is obtained by adjusting the detected color value of each color against a dark current and a background value. Thereafter, the microcomputer 70 can find a generated corrected signal by obtaining one set of values of a relevant density from the test pattern by converting each reflectance value into a density value.