Generally speaking, when a full-color LED display screen runs for a certain period of time, all LED light-emitting tubes will inevitably have brightness attenuation, and the attenuation curves of the three primary color tubes are not the same. So their brightness will be lower than when they left the factory. Because of the difference in the photoelectric characteristics of each LED light-emitting tube, the degree of brightness reduction is error. Therefore, after the display screen is actually used for a period of time, the brightness of the luminous tube will be attenuated to different degrees, which will make the display between the pixels not uniform enough, and then compare with the factory screen to show a granular display state , Or the overall brightness is reduced. Inconsistent decay curves of the three primary color tubes will cause changes in white balance and color temperature.
Due to factors such as the attenuation of the LED light-emitting tube and the ambient temperature, in practical applications, it is almost inevitable that the display function will deteriorate at the time of shipment. It is impossible to complete the installed full-color LED display screen and transport it back to the supplier for calibration. In view of these characteristics, it is necessary for full-color LED display manufacturers to perform calibration on site to ensure In future applications, the display can still maintain the same effect as it was at the factory.
Full color LED display
There are two on-site calibration methods:
1. Correction method based on the running time of the full-color LED display: This is an early on-site correction method, which corrects the display according to the tracking record and the running time of each led module. Carry out a rough calculation of the working time of each led module to determine its respective working time.
Therefore, the brightness attenuation will be estimated as a different correction level before being sent to each led module for corresponding adjustment. Although this method does not require any manual input, it ignores the attenuation of the LEDs, which is estimated at runtime.
This frequency will not be applied to every deletion. With the passage of time, the fluctuation range of the attenuation frequency of the full-color LED display will become larger and larger, and the correction will be carried out on a uniform basis, so that some of the LEDs are close to the corrected level, while the other part of the led screen will become Increasingly inconsistent. Because the brightness of each led module is different, and there is no effective way to adjust the brightness of these modules that do not match, so when the uniformity adjustment between different modules is running, a series of problems will appear, the most serious However, this kind of magnification cannot achieve magnification between pixels. Therefore, after this correction, the full-color LED display screen gives people the overall impression that there is a mosaic phenomenon, which cannot well improve the uniformity of the later display screen.
2. According to the site conditions, a unified correction method is adopted: in order to completely improve the uniformity of the full-color LED display, it is necessary to use special collection equipment to quickly collect the light and color information of each pixel on the full-color LED display. , And compensate the actual attenuation of each LED light-emitting tube through the relevant algorithm, and then complete the common correction, even if the work of the led module cannot be performed at the same time, the pixel-level correction can be completed. The corrected display can be restored to the original effect.
