If you want to tell the brightness of LED display, how much do you know about LED display brightness? LED lighting has been recognized as the most energy-efficient lighting. However, the brightness of the LED diode available on the market not consistent, which is difficult to distinguish even with the naked eyes. Everyone knows that the brightness of white astigmatism LED light-emitting diode is divided into several brightness levels, which is one of the important performance indicators of the light emitting diode; commonly used LED light-emitting diodes in the lighting generally use the brightness of 1400-1600MCD arc tube as light source. However, the LED light-emitting tube on the market is a mixture of ichthyosaur, the quality is uneven, or brightness is not guaranteed. The light emitting diode marked with brightness 1400-1600MCD in the store doesn’t reach the marked brightness, which deceive consumers by shoddy products. Most people do not have the ability to identify LED brightness,led display manufacturer say how much brightness is then you would think the brightness is how much. For the size of the brightness, it is not the bigger the better. But according to the customers' needs, the appropriate size of the brightness will achieve an unexpected effect.
Methods to identify the brightness of the LED display
1. Make an easy connection 3V DC power supply for light-emitting diodes by yourself, it's best to produce with batteries. You can use two button batteries, pack them in a small plastic tube and lead two probes as positive and negative output, directly make the end of shrapnel into a switch. When using, the positive and negative probe correspondingly contact with the light-emitting diode positive and negative pin, press and hold the end of the switch, the light-emitting tube is luminous.
2. Secondly, combining the photoresistor and digital multimeter into a simple metering device, leads two thin wires from photoresistor and directly connect to the two pens on digital multimeter table, placing multimeter stalls on the 20K position (photoresistor, making the readings to be as far as possibly accurate), note that the actual measured value is the photosensitive resistor, so the smaller the value, the brighter the light.
3. Take an LED light-emitting diode, light by the above 3V DC, luminous head opposite and close to the photosensitive surface of connected photosensitive resistance, then there is reading in the multi-meter, which can distinguish the luminous intensity of LEDs.
Brightness level discrimination of LED display
Luminance authentication hierarchical refers that the luminance level of the image can be distinguished by the human eyes from the darkest to the most white. Sometimes, the gray scale of display is very high, which can be up to 256 or even 1024. However, because the sensitivity of the human eye for 360 led display brightness is limited, they cannot fully identify these gradations. It means that a lot of adjacent gray levels look like by human eyes. And each person has varied eyes ability to distinguish. For display, the level of the human eye recognition is naturally higher the better, because the displayed image is to be seen by human after all. The more brightness level the human eye can distinguish, the larger display color space, meaning the potential of rich colors is greater. Brightness level discrimination can use special software to test. Generally the display up to 20 or more grade is even better.
Requirements for LED display brightness and viewing angle
Brightness and viewing angle indoor full color brightness should be above 800cd/m2 and outdoor full color screen brightness should be above 1500cd/m2, which can ensure the normal work of the display, otherwise it's too dark to see the displayed image due to the too low brightness. The size of the brightness of large led displays is decided by whether the LED die is good or bad. The size of the viewing angle directly determines how much about the LED display audiences, therefore the bigger the better. Perspective is mainly decided by the die package.
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