as a publicity medium for use, we should know some LED screen knowledge, below we will explain some how to distinguish the brightness of LED display screen knowledge.
First, let's take a look at what is the brightness of the LED display: LED light-emitting tube brightness refers to the intensity of light emitted by the luminous body, called light intensity, to MCD.
LED screen luminous brightness is a composite index, which refers to: all LED modules in the unit volume of luminous total (luminous flux) and at a certain distance of the illumination of the comprehensive indicators.
LED display brightness: In a given direction, each unit area of the luminous intensity of the unit is cd/m2. The brightness is proportional to the number of LEDs per unit area and the brightness of the LED itself. The brightness of the LED is directly proportional to its driving current, but the life expectancy is in inverse proportion to the square of the current, so the driving current cannot be increased in order to pursue brightness.
At the same point density, LED display brightness depends on the use of LED chip material, package form and size, the larger the chip, the higher the brightness, conversely, the lower the brightness.
So what are the brightness requirements of the ambient brightness for the screen?
General brightness requirements are as follows:
(1) Indoor LED display: >800cd/m2
(2) Semi-indoor LED display: >2000cd/m2
(3) Outdoor LED display
(sitting north of the Southern Dynasty): >4000cd/m2
(4) Outdoor LED display (south): >8000cd/m2 The market sells led light-emitting tube quality is uneven, the brightness most cannot guarantee, the shoddy phenomenon deceives the consumer, the majority did not discriminate the LED luminous tube brightness ability.
And the light is indistinguishable from the naked eye, so how to identify it?
How to identify the brightness of LED electronic display
1. Make a 3V DC power supply which is easy to connect with light-emitting diode, preferably made of battery.Can use two button batteries, installed in a small plastic pipe and two probes as positive and negative output, tail end with shrapnel directly into a switch, when used, the positive and negative probe corresponding to contact light-emitting diode positive and negative pins, hold down the end of the switch, light-emitting tube to be electroluminescent.
2, secondly, with photoresistors and digital multimeter combined into a simple metering device, the photoresistors leads to two fine wire, directly connected in the digital multimeter two pens, multimeter stalls placed in the 20K position (depending on the photoresistors, as far as possible to make the reading accurate), note that the measured value is actually photoresistors resistance, so,The lighter the light, the smaller the value.
3, take an LED light-emitting diode, with the above 3V DC Electric Light, light-emitting head is right and close to live connected photoresistors of the photosensitive surface, at this time, the multimeter appears reading, to distinguish the luminous brightness of the LED.
Second, the brightness identification level, refers to the human eye can distinguish between the most black and white brightness level. LED display has a high level of gray, can reach 256 or even 1024 levels. However, due to the limited sensitivity of the human eye to brightness, it is not possible to fully recognize these gray levels. That is to say, there may be many adjacent levels of gray people look the same. and eye-resolution is different for each person. For the display, the level of recognition of the human eye is naturally the more the better, because the display of the image is for people to see. The more brightness levels the human eye can distinguish, the larger the color space of the display screen, and the greater the potential for rich colors.
Brightness identification level can be used to test the specific software, the general display can reach more than 20 level is a better grade.
Third, brightness and visual angle requirements: Indoor Full-color LED display in the brightness of 800cd/m2 above, outdoor full color screen brightness to 1500cd/m2 above, to ensure the normal work of the display, otherwise, because the brightness is too low to see the image displayed. The size of the brightness is mainly determined by the quality of the LED tube core. The size of the visual angle directly determines the number of LED display audience, so the bigger the better.
The angle of view is mainly decided by the tube core package. Determine the brightness of LED display is very necessary, the current city lighting LED display brightness requirements, or a new regulation, LED screen brightness is too high, it will cause trouble to nearby residents.
In order to avoid adverse repercussions, this requires the business in the customization and maintenance of LED signs
requires relevant expertise. The above is how to distinguish the real LED display brightness index brightness of the method, I hope to help you, another LED display brightness size is not larger the better, but according to the use of demand, the appropriate brightness will achieve unexpected results.