With the development of science and technology, the performance of today's semiconductor light-emitting diodes has reached a new level, and its photoelectric conversion efficiency has reached more than 10cd/w, especially the emergence of blue ultra-bright LED devices, making the spectrum of LED devices cover the range of natural light .
The visual principle of the full-color LCD advertising machine display is the same as that of a color TV. The color of the image is restored and reproduced through the different light intensities of the three colors of red, green and blue. The purity of red, green, and blue directly affects the visual effect of image color reproduction. However, the three-color ratio of white light is not a simple superposition of three colors.
În primul rând, sub premisa asigurării purității frecvenței optice, raportul dintre intensitatea roșu, verde și albastru trebuie să fie apropiat de 3:6:1;
Second, due to people's visual sensitivity to red, red light sources are required to be distributed in space;
Third, because people's vision responds to the different nonlinear curve of the three colors of red, green, and blue, it is required that the white light with different intensities needs to be -corrected similar to that in a TV for red, green, and blue;
În al patrulea rând, vederea umană are capacitatea limitată de a distinge diferența de culoare. Prin urmare, trebuie găsit un indicator obiectiv al autenticității reproducerii culorilor imaginii.
Pentru a reproduce culoarea reală a imaginii, următoarele cerințe trebuie îndeplinite în distribuția luminii a afișajului mașinii de publicitate LCD:
① The wavelengths of red, green and blue should be about 660nm, 525nm and 470nm respectively;
② It is better to use a 4-tube unit with white light (multi-tube unit is also possible, depending on the light intensity);
③ The gray levels of red, green and blue are 256 levels;
④ Non-linear correction for LED pixel tubes must be adopted.
Distribuția luminii roșii, verzi și albastre și corecția neliniară pot fi realizate de hardware-ul sistemului de control al afișajului sau de software-ul sistemului de redare.
