What is led display
Author:Jiang Yan Time:2021-06-07 10:15 Browse(168)
In some semiconductor PN junctions, when the injected minority carriers are combined with the majority carriers, the excess energy will be released in the form of light, thus the electric energy can be directly converted into light energy. When the reverse voltage is applied to the PN junction, it is difficult to inject a few carriers, so it does not emit light. The use of injection type electroluminescence principle of the production of the diode called light-emitting diodes, referred to as LED.
In the PN junction of some semiconductor materials, when the injected minority carriers are combined with the majority carriers, the excess energy will be released in the form of light, so that the electric energy can be directly converted into light energy.
the PN junction is applied with reverse voltage.

What is led display

the minority carriers are difficult to be injected, so they do not emit light.
this kind of diode made by the injection electroluminescence principle is called light emitting diode.
it is referred to as LED.
in shortThe luminous color and luminous efficiency of LED are related to the material and process of making LED.
at present, red, green and blue are widely used.
because the working voltage of LED is low (only 1.5-3V).
it can emit light actively and has a certain brightness, and the brightness can be adjusted by voltage (or current), and it is shock resistant, vibration resistant and has a long service life (100000 hours), so in large-scale display equipment, At present, there is no other display mode that can match the LED display mode.
there is no other display mode that can match the LED display modeThe red and green LED together as a pixel production screen is called two-color screen or color screen; A display screen with red, green and blue LED tubes as a pixel is called a three color screen or a full color screenNo matter using led to make monochrome, bicolor or tricolor screen.
to display an image, the brightness of each LED that constitutes a pixel must be adjusted, and the fine degree of adjustment is the gray level of the display screen.
the higher the gray level is.
the more delicate the image is, the richer the color is, The corresponding display control system is more and more complex.
generally, the color transition of 256 level gray image is very soft, while the color transition boundary of 16 level gray image is very obvious.
therefore.
Color LED screen is required to be 256 level gray.
at presentWorking principle of LED displayLED electronic display screen is a high-tech product integrating optoelectronics and computer technology.
this paper introduces the development of LED electronic display screenThe overall block diagram is as follows:Performance characteristics of LED productsThe text LED display screen and graphic LED display screen shall have the moving in / out mode and display mode specified in the detailed specification.
the text LED display screen and graphic LED display screen shall have the moving in / out mode and display mode specified in the detailed specificationComputer video LED display should have animation function.
it is required that the animation display of LED display should be consistent with the corresponding area of computer display; Text display function.
text display should be stable, clear and crosstalk; Gray level function.
it is required to have the gray level specified in the detailed specification.
in addition to animation, text display and gray level function,
TV video LED display should be able to show TV and video pictures.
market led display should have the corresponding market display ability.
TV video LED display should be able to show TV and video picturesHow to classify LED displayLED displays can be classified according to the following conditions:·According to the use environment, LED display can be divided into indoor LED display and outdoor LED display·The display color LED display screen can be divided into single primary color LED display screen (including pseudo color LED display screen).
dual primary color LED display screen and full-color (three primary color) led display screen.
according to gray level, it can be divided into 16, 32, 64, 128, 256 gray level LED display screen, etc.
according to gray level, it can be divided into three levels·Display performance LED displays are divided into text LED display, graphic LED display, etc.
computer video LED display, TV video LED display and quotation LED display, etc.
quotation LED display generally includes LED display for securities, interest rate, futures and other purposes.
according to the display performance, LED display can be divided into text LED display, graphic LED display, etc.
computer video LED display, TV video LED display and quotation LED display·According to the single point diameter of LED used, indoor LED display can be divided into three categories Φ 3mm、 Φ 375mm、 Φ 5mm、 Φ 8mm, and Φ 10 mm, etc; The outdoor LED display screen can be divided into three parts according to the pixel diameter Φ 19mm、 Φ 22mm and Φ Mm26The market led displays can be divided into 2.0cm (0.8inch), 2.5cm (1.0inch), 3.0cm (1.2inch), 4.6cmm (1.8inch), 5.8cm (2.3inch), 7.6cm (3inch) led displays according to the size of nixie tubeHow to evaluate the quality of LED screen?·The out of control point of indoor LED display should be no more than 3 / 10000.
the out of control point of outdoor LED display should be no more than 3 / 1000, and it should be discrete;·Consistency the consistency of LED screen is better, the brightness of the whole screen should be balanced, without obvious color block;·There is no potential safety hazard and leakage current, and the leakage current to the ground shall not exceed 3.5ma (AC effective value); Anti spot strength: the LED display screen can withstand the test voltage of 50 Hz and 1500 V (AC RMS), and the insulation breakdown shall not occur; At the same time, LED display should have warning signs at fuse and switching power supply;·There should be no obvious scratch on the outer frame of LED display screen.
the pixel tubes of outdoor LED display screen should be installed in the same way.
there should be no looseness and tube shell fracture;·Structure: the LED display panel can be made of steel, aluminum, wood and other materials, and the structure is required to be solid and beautiful.
.
.
Related topics