CRT projection display apparatus and color correction method thereof

Abstract

A CRT type projection display device having a plurality of CRTs whose cathodes are fed with primary color video signals and displays images projected from each CRT onto a screen. The device includes a separation section which separates a synchronizing signal from an input video signal; a correction signal generator circuit which generates a correction signal for correcting uneven colors on a screen by utilizing said synchronizing signal; a control circuit , which controls said correction signal according to the luminance level of the primary color video signal fed to the CRT; The uneven colors on the screen caused by each CRT.

Description

technical field [0001] The present invention relates to a CRT type display device using a primary color CRT (cathode ray tube), and more particularly to a CRT type projection display device which corrects uneven colors due to different projection angles of each CRT. Background technique [0002] CRT-type projection display devices using primary color CRTs (blue CRT, green CRT, red CRT) are set so that their projection angles are different from each other, and those adjacent right and left CRTs are arranged in a predetermined position relative to the central CRT. angle setting. As a result, there are slight differences in the brightness distribution of each primary color image on the screen, which leads to uneven colors when a pure white display is performed. [0003] As a conventional technique for optical disc devices (Japanese Patent Application Laid-Open No. 3-151786), an example is known in which uneven colors are corrected on a CRT type projection display device. Here...

AI Technical Summary

Problems solved by technology

As a result, the brightness distribution of each primary color image on the screen is slightly different, which can lead to uneven color when displaying all white

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