6 reasons why LED light source becomes the savior of projection

The 20th century had the most inventions, and it is no exaggeration to say that it is one of the greatest inventions of the 20th century. Compared with oil lamps and incandescent lamps, LED light sources are called the third generation of light sources. What are the advantages of LED light sources? Why use LED technology in projectors ?

LED light source

LED technology has a wide range of applications, and the most common ones are LED projectors, LED TVs and LED displays . To be precise, they should be called LED light source projectors, LED backlight TVs and LED backlight displays .

Three-color LED projection Structure

LED backlight LCD structure

At present, LED technology can be applied in almost all fields: a. LED display technology - LED splicing wall; b. LED backlight application - LED projector, LED backlight flat-panel TV ; c. LED lighting application - LED lighting, LED flashlight, LED car taillight; d. LED decoration application - LED decorative lamp; e. LED signal indicator, which can be found in almost all electrical equipment. Traditional light source projectors can meet most usage requirements in terms of brightness , but the short-lived ultra-high pressure mercury design makes home users give up projection and turn to flat-panel TVs; the toxic and harmful mercury element, which has mixed reputations, is the enemy of environmentalists; the expensive late-stage bulb investment is very inconsistent with the consumption habits of Chinese people, which makes small and medium-sized enterprises feel great pressure. Compared with the prosperous scene of LED technology, LED projection seems to be unable to cope with it.

Due to various drawbacks, facing the ever-expanding projection demand market, traditional light source projectors have become a little tired, so can LED become the savior? With the release of Texas Instruments ’ micro HD DLP chip, high-definition micro-projection has become the future development trend. The resolution of 500 lumens and 1280×800 has rekindled our enthusiasm for the application of LED light sources.

1. Simple principle and ultra-long life

Due to the special structure of LED, LED has an inherent advantage of life that other light sources cannot compete with.

LED structure diagram

The first advantage of LED projectors is their extremely long lifespan.

Traditional light sources, such as the mainstream ultra-high pressure mercury lamp, generally have a service life of 3,000 hours in normal mode. Compared with traditional light sources, the service life of LED light sources is generally between 50,000 and 100,000 hours, which is more than 20 times that of traditional light sources.

Luxeon light decay diagram

In real life, we have a big misunderstanding: our hardworking parents always remind us to save electricity by turning off the lights. However, this method not only does not save electricity, but also greatly shortens the service life of bulbs and tubes. Traditional light sources are frequently turned on and off, and the instantaneous current shock consumes a lot of electricity and greatly shortens the life. However, due to the structure of LED, frequent turning on will not affect the service life. For frugal elders, LED is more suitable. The same is true for projectors. Through our tests , after the projector with traditional light source is turned on, the power consumption will continue to soar, fluctuating up and down for a long time. When the brightness is stable, the power consumption will be maintained within a small fluctuation range.

Light decay diagram

We are all used to watching TV, especially the elderly at home. TV is an indispensable element in life. It is even common to turn it on for nearly 18 hours. For traditional projectors, the service life of 3,000 hours will not last for half a year. This is also the real reason why home projectors cannot be promoted, which is incompatible with our traditional concepts. LED projectors can last for as short as 60,000 hours and as long as 100,000 hours. Even if it is turned on countless times a day and the power-on time exceeds 20 hours, the LED projector can still work normally for more than 7 years under such torture.

2. Instant startup without a lighting device

Advantage 2 of LED projector: no need for lighting device, instant startup

Projectors with traditional light sources all have a built-in lighting device, which is why traditional light sources take a long time to start up.

Projection lamp igniter schematic diagram

Schematic diagram of ultra-high pressure mercury lamp structure

Compared with traditional light sources, LEDs can work at low voltages and do not require a lamp. In addition, LEDs have very fast response times, theoretically in the microsecond range.

LEDs made of different materials have different response times. For example, the response time of GaAs, GaASP, and GaAIAS is less than 10 nanoseconds, and that of GaP is 100 nanoseconds. Microsecond, a unit of time, symbol μs (English: microsecond ) , 1 microsecond is equal to one millionth of a second (10 to the negative 6th power of a second).

3. Solid-state luminescence, strong and durable

Advantage 3 of LED projector: solid-state light emission, strong and durable

Incandescent lamps have the simplest structure, not only have a short lifespan, but the filament is also easy to break. They are the main type of light bulbs that are being vigorously eliminated both at home and abroad.

China's Incandescent Lamp Phase-out Plan Implementation Table

Whether it is a fluorescent lamp, high-pressure mercury lamp, halogen lamp, xenon lamp or arc lamp, they all have a glass shell and need to be evacuated or filled with special gas inside the glass lamp tube. Therefore, not only does it require the assistance of a lamp igniter, but it also has the possibility of breakage.

Automobile headlight structure

In terms of structure, LED has no glass shell, and there is no need to evacuate or fill the lamp tube with special gas; LED lamps are highly resistant to earthquakes and impacts, and are more convenient in production, transportation, and use. The most powerful application may be the large outdoor billboards at the joints of LEDs, which can withstand wind and rain, which is unmatched by other lighting equipment.

Portable LED projector

Whether it is an LED micro projector or an LED portable projector, normal shaking is fine, unlike traditional light source projectors. For LED projectors, you don’t have to pay attention to the “handle with care labels and do not move them at will” warning.

4. Energy concentration and strong directivity

Advantage 4 of LED projector: strong light directionality

The light energy is highly concentrated and is concentrated in a smaller wavelength range.

Wavelength range

A large number of LED applications require cylindrical or spherical packaging, which has strong directivity due to the effect of convex lenses .

Scattering angle diagram

The scattering angles (2θ1/2 angle) of several commonly used circular LED packages are: 5°, 10°, 30°, and 45°.

Many domestic experts say that the light energy conversion rate of LED is 80%, but that is just a word game. Everyone knows how high the heat of a light bulb is, and it is impossible for the conversion rate to be greater than 50%. LED flashlights are also very hot, and flashlights are also hot when they light up. Overseas technical data is more reliable. LED DC drive has an electro-optical conversion efficiency of nearly 28%, which is the highest among existing known luminescent materials.

5. Lightweight and environmentally friendly

Advantage 5 of LED projector: light weight

LED components can be made very small, which is convenient for various combination designs, layout installation and integrated applications.

80 0.1W low- power LEDs in series

25 1W LEDs are connected in 5 parallels and 5 series on the chip

80 0.1W low-power LEDs are connected in series, and 25 1W LEDs are connected in 5 parallels and 5 strings on the chip. Even with such a complex design, the LED can still maintain a very slim body. In the field of projectors, there are LED portable projectors the size of optical drives, and LED micro projectors the size of mobile phones .

LED Micro Projector

On the market, LED portable projectors generally weigh around 1 kilogram, and micro projectors weigh around 250 grams.

6. Advantages of LED projectors: green, environmentally friendly, and new energy

Due to the unique mercury-free design of LED, it is one of the representatives of new energy and a new industry vigorously supported by governments of various countries.

In summary:

1. LED light source projector can subvert our traditional concept of projector.

2. LED light source has very promising future prospects and financial prospects.

3. With the development of technology and the popularization of products, the price of LED light sources is getting lower and lower, making them easier for users to accept.

4. Green and environmentally friendly, the mainstream application in the future.