Evaluate led standards

Evaluate led standards

Reprinted from: http://www.eslighting.cn/2010/0419/162_2.html

Author: LED times Network

 

As a lighting product, the following factors must be taken into account:
Luminous flux and Efficiency

Colors, colors, heat dissipation design, and reliability

1. Luminous flux and efficiency (typical brands)

		3000 K	4000 K	6000 K
rebel Philips lumileds Philips lumen		luminous flux: 77lm color rendering: 85 luminous efficiency: 71 lm/W	luminous flux: 85lm color rendering: 85 luminous efficiency: 78lm/W	luminous flux: 105lm color rendering: 70 luminous efficiency: 97lm/W
oslon Osram		luminous flux: 85lm color rendering: 80 luminous efficiency: 76lm/W	luminous flux: 90lm color rendering: 80 luminous efficiency: 80lm/W	luminous flux: 110lm color rendering: 70 luminous efficiency: 100lm/W
Xpe Cree Corui		Luminous flux: 85lm Color Rendering: 80 Luminous Efficiency: 78lm/W	Luminous flux: 90lm Color Rendering: 80 Light efficiency: 83lm/W	Luminous flux: 110lm Color Rendering: 75 Luminous Efficiency: 100lm/W

Low-power LED

		Low brightness		High Brightness
		2700 K	6000 K	2700 K	6000 K
3528led		luminous flux: 4 lm color rendering: 70 luminous efficiency: 63 lm/W	luminous flux: 4.5 lm color rendering: 70 luminous efficiency: 72 lm/W	luminous flux: 5.5lm color rendering: 70 luminous efficiency: 88 lm/W	luminous flux: 6.3 lm color rendering: 70 luminous efficiency: 100 lm/W
5050led		Luminous flux: 11 LM Color Rendering: 70 Light efficiency: 58 lm/W	Luminous flux: 13lm Color Rendering: 70 Light efficiency: 68 lm/W	Luminous flux: 16lm Color Rendering: 70 Luminous Efficiency: 85 lm/W	Luminous flux: 20lm Color Rendering: 70 Luminous Efficiency: 100lm/W

2. Color

The color accuracy is related to the phosphor coating.

Accurate Control of the chip Coating Thickness and concentration, you can accurately control the color of production.High-power first-class enterprises have been produced in accordance with ANSI requirements, which can meet the basic requirements of lighting, but the color of each partition is still visible to the naked eye.Small-power packaging enterprises have not been standardized, so the colors produced are greatly different from the CIE standard. Many enterprises do not understand the CIE standard yet, according to the original standard for mobile phone LCD screen, this will not meet the lighting requirements, the color table is very poor, although the brightness is very high, it is difficult for customers to satisfied.

The CIE standard is the lowest standard for customer satisfaction. If this standard cannot be met, we will not be able to talk about lighting applications.
3. Heat Dissipation Design


YesThe evolution of lumileds high-power LEDs. Early Low PowerLEDs, for example, 5 mmled, heat dissipation through the bracket, so the heat dissipation capability is poor, the thermal resistance reaches 240; The pirat is 120; and the high-power LED can reach 12 at the beginning. Thermal resistance is an indicator of heat dissipation capability. For example, if the pad temperature is the same70 degrees 5 mmled Thermal Resistance240 degrees/watt, current 20mA, tube pressure 3.3 V, led node temperature = 70 + 240 × 0.02 × 3.3 = 85.84 degrees K2 Thermal Resistance12 degrees/watt, current 350mA, tube pressure 3.2 V, led node temperature = 70 + 12 × 0.35 × 3.2 = 83.44 degrees Rebel Thermal Resistance10 degrees/watt, current 350mA, tube pressure 3.1 V, led node temperature = 70 + 10 × 0.35 × 3.1 = 80.85 degrees It can be seen that although the power is getting bigger and bigger, the internal temperature is getting lower and lower, this isDevelopment Trend of LED cooling.

The ceramic substrate adopts Aluminum Nitride Ceramic, and the thermal conductivity exceeds the copper index, while the expansion coefficient is close to that of the silicon wafer, which greatly improvesLed stability. Ceramic Material plays an irreplaceable role in the development of LED.