Questions Analysis of High-power LED in Application

This technical article analyzes twelve questions of high power LED during its application.

1. Chromatic aberration

Individual LED basically has no chromatic aberration problem, however, if there are a lot of LEDs being put into use, or a lamp with multiple LEDs at the same time, the problem will appear. Although like LUXEON will divide LED by the color temperature into eight major military commands, and then points in each military area command aura several parts, which control a wide range of color difference in a certain degree, but with a batch of LEDs in a same quality still exists difference, and this difference is still cannot escape the provocation of people's eye.

2. Insulation

(The insulation mentioned here refers to LED heat dissipation base to the positive and negative terminals). Many famous manufacturers are surprised at this problem. It is still not settled and only some remedial measures are taken. There is no problem for a single LED has insulation question, while series will influence.

3. Anti-impulse

It is still in controversy, which indeed exists in application. It is mainly reflected on cold pulse, which means the moment LED is powered on, some of them will breakdown.

4. Irritation angle

Because LED lens packaging of various manufacturers is different, even the same irritation angle has different effect, which makes the selection of snoot more difficult. 

5. The risk of potential blindness

LED luminous point is too centered, which makes the central point is so bright that is easy to hurt one’s eyes. Although some light producer try to make an effect, the influence is still not so obvious.

6. Heating problem

Theoretically, LED does not heating seriously, but with present immature technology, the problem is well known.

7. Low efficiency (luminosity factor)

At present LED electrothermal conversion efficiency is too low.

8. Inadequate luminance

It makes LED now play a support role in lighting industry, which is mainly used for decoration.

9. Light failure and service life

At present, LED from mainland or Taiwan has serious failure and service life problem. Some famous producer such as LUXEON indicates that their LED has 100,000h life. However, we know that the quality of heat dissipation and driver will also influence LED failure and service life. 

10. Driving power

At present most of the driving circuit is borrowed from switching power supply, of course, there are only a few lines is dedicated to the LED driver, but the effect is essentially the same. Because the LED dc drive is required and takes constant current control, which makes the drive circuit quite large and the efficiency is low. In addition, the manufacturer claims a drive can take ten or more LED for applicability, in fact this is a myth, though it is constant current, high starting voltage will often cause LED to break down in the moment.

11. Limited shape

LED single light feature make its limited shape.

12. High unit price

A foreign LED with 1W to 3W will cost $3, and our LED needs 10yuan or more (which has poor quality and no intellectual property). A lamp with 6 LEDs takes consumers about 1,000yuan.