Method for preventing CRI fron heat injury caused by still picture

Abstract

The invention discloses a method for preventing still images from burning a CRT, comprising the following steps: using an OSD circuit module to generate red, green and blue primary color OSD signals for forming a low-brightness area on a fluorescent screen; setting the OSD switch control signal The high level of the above-mentioned low-brightness three-primary-color OSD signal is formed into a translucent low-brightness three-primary-color OSD signal; the scanning start time of the signal generated by the control OSD circuit module; the translucent low-brightness three-primary-color OSD signal and The signal generated by the video decoding circuit unit to form a normal TV picture is superimposed by the superimposing unit; the superimposed signal is used to control the imaging circuit of the CRT. In this way, the brightness of the still image is reduced, and it is not easy to leave burn marks on the fluorescent screen of the CRT, which protects the CRT and prolongs the service life of the TV set.

Description

technical field [0001] The invention relates to the imaging of a television CRT (cathode ray tube), and is especially applied in preventing specific areas of the CRT from being burned by fixed high-brightness images. Background technique [0002] At present, most TV sets use CRT (cathode ray tube) as the imaging unit, such as ordinary CRT TV, flat-screen CRT TV, rear projection CRT TV and so on. With the improvement of CRT production technology and quality, the brightness and contrast of TVs based on CRT imaging principles have been significantly improved, and the TV screens appear very bright. But because there are often static and unchanging image contents on the TV screen, such as figure 2 The TV station logo (such as CCTV-1) and time signal shown, the fixed display content output by the DVD player (such as disc information), etc., coupled with the high brightness characteristics of the CRT, these still images will soon be displayed on the CRT. Permanent burn marks are ...

AI Technical Summary

Problems solved by technology

But because there are often static and unchanging image contents on the TV screen, such as figure 2 The TV station logo (such as CCTV-1) and time signal shown, the fixed display content output by the DVD player (such as disc information), etc., coupled with the high brightness characteristics of the CRT, these still images will soon be displayed on the CRT. Permanent burn marks are left on the fluorescent screen. Slight marks will affect the effect of watching other TV screens. In severe cases, it is even necessary to replace the CRT to continue to watch normally.

Images