LED color calibration

In factory calibration
In general, as a result of the LED's wide range of brightness and color, the general filtering and selection procedure cannot fully unify the LEDs brightness and color onto a display.OPTOTECH, however, has managed to bypass this challenge by developing the chromaticity measurement and correction system. This system can adjust every unit of the LED brightness and chroma and keep the difference below 5% so as to ensure optimum LED uniformity.

On site calibration
Why on-site color calibration?
The imbalance in uniform brightness and color shade of display might be caused by the following reasons:

•  • Not performing factory calibration of each module during the manufacturing process.
•  • The maintaining, reworking or repairing of display.
•  • LED will be polluted or decayed by environmental condition or time.

The effect of calibration

•  • Each LED pixel’s value can be adjusted in uniform brightness and color shade.
•  • Improves the uniformity in color shade and brightness of whole display
•  • Retains the quality of display on uniform brightness and color shade over time.

The consideration of calibration
With regards to the implementation of calibration, there are five factors that have to be considered.

•  •  Environment: calibration is implemented at night without any lighting affection. Therefore, it is essential to evaluate the lighting from the surroundings and avoid illumination from street lights.
•  • Distance: the best distance of remote communication for sending each pixel calibration data between measure device and the display is 50m to 100m.
•  • Power: at least four sets of AC power for calibration device.
•  • Working day: the working day of calibration depends on the size of display.
•  • Limitation: calibration service is only for on-site display, not including spare parts.

Virtual pixel sharing techlology

Specific RGB LED design and accurate driver controlling technology improves the image caused by the edge-line effect. OPTOTECH's virtual pixel technology enables every LED pixel to be shared by the surrounded pixel, increasing the resolution three or four fold, hence delivering a higher quality image to the human eye. This system is an economical way of increasing resolution with a controlled number of LEDs.

16 bit color depth

With the development of the driving system and gamma correction technology, OPTOTECH is able to successfully diminish the flickering and interference in the lower scale of brightness and lightness area. 16 bit from OPTOTECH is able to demonstrate more than 280 trillion colors grey scales on red, green and blue. Brightness varies from 0.08nit, 0.16nit, 0.24nit, 0.32nit. In addition, the 16 bit grey scale smoothly enhances the dim pixel image and enhances the picture quality of the display.

Video processing technoloty

Video processing technology provides a complete digital image product system. Through transforming the input signals to all digitalized image data and output to the display, the technology can fully support a resolution of up to 1024 x 768 and give a 24 bit full color image. As a result of this technology, OPTOTECH has managed to create some space between itself and the competition, and effectively lead the field.