There are two big factors that affect brightness consistency. One is the choice of raw material chip, the other is the control mode adopted when using digital tube.
1, raw materials -LED grain VF and brightness and wavelength is a normal distribution, even after screening LED grain, VF and brightness and wavelength has been in a very small range, the production of the product is still in a range, the result is inconsistent brightness.

2, to ensure the LED digital tube brightness, there are also differences in the selection of control mode, the best way is constant current control, flow through each LED diode current is the same, so the LED diode looks the same brightness. Such as constant voltage control, the led diode with different VF current is not the same, so the brightness is different. Of course, these two conditions are complementary.