LED lighting products blue light hazard detection analysis and rich blue analysis and suggestions

Recently, medical experts worry that LED blue light will cause damage to the retina or even blindness. This news has aroused widespread attention and a large number of reposted comments on the Internet, as well as a lot of attention from light source experts. A few days ago, the Shanghai Quality Supervision Bureau specially organized testing agencies to conduct risk monitoring on some LED lighting products, collecting 27 samples from different channels for blue light risk testing. At the same time, the bureau also invited experts from the medical community, universities and industry for a "consultation" for the first time to "cross-border" to listen to the opinions of all parties.

Yu Anqi, deputy director of the National Electric Light Source Quality Supervision and Inspection Center (Shanghai), professor-level senior engineer, deputy general manager of Shanghai Times Light Lighting Electrical Inspection Co., Ltd., and chairman of the Shanghai Lighting Society, conducted a detailed analysis of the LED blue light hazard detection. And the article "Detection and Analysis of Blue Light Hazards of LED Lighting Products and Analysis and Recommendations of Rich Blue" is published. In this article, Yu Anqi mentioned that blue light hazards and "rich blue" lighting effects are not unique to LED lighting products. Some metal halide lamps and some fluorescent lamps have long existed before.

In addition, Yu Anqi emphasized in the article that blue light is an important part of white light, so it is one-sided to filter out blue light under normal circumstances. It is correct to select the light composition and quality according to the physiological rhythm of the person. In order to avoid possible adverse effects on human health due to the use of high color temperature and rich blue light LED lighting products, the color temperature of indoor LED lighting products should not exceed 4000K, and the general color rendering index should reach more than 80. Indoor lighting should avoid the use of LED lighting products with a color temperature of 5000K and above. At present, the promotion of low color temperature LED product technology and cost is completely feasible.

The advancement of technology has led to the continuous emergence of various lighting sources. These light sources can also cause harm to people because of improper use while enriching lighting products and meeting people's needs. For example, what is the actual situation of the blue light hazard of LED, which is currently spread widely? According to international standards, LED lighting products that are determined not to cause blue light hazards, how will their "blue-rich" lighting affect people's physiology? From the development of LED lighting to the present stage, we should have more in-depth research on this to make the development of the industry healthier.

1. Detection and analysis of blue light hazards

According to the possible blue light hazards of LED products, understand the blue light hazards of LED lighting products on the market. And related analysis is as follows:

1. Sample source and composition

(1) Sample source

The total number of tested samples is 27, which are from:

-8 samples were purchased from small informal stores;

-5 samples were purchased from large supermarkets;

-14 samples are the test samples of large and medium-sized production enterprises.

(2) Sample composition

Among the 27 samples, 8 LED desk lamps, 7 LED spotlights, 9 LED downlights, 1 LED bulb and 2 LED flat lamps.

2. Test purpose and basis

Detect and evaluate the blue light hazard of retinal LED lighting products.

Standard for detection and classification: GB / T 20145-2006 Photobiological safety of lamps and lamp systems

Hazard determination basis document: IECEE CTL (International Electrotechnical Commission-Laboratory Committee) Resolution: DSH 0744

3. Blue light hazard level and corresponding requirements

(1) Blue light hazard level

According to GB / T 20145-2006 blue light retinal hazards can be classified as:

1) Non-hazardous (radiance ≤100 W · m-2 · sr-1): The scientific basis of non-hazardous category is that the lamp does not cause any photobiological harm to this standard under extreme conditions;

2) Low risk (category 1) (radiance ≤1 & TImes; 104 W · m-2 · sr-1): the lamp does not cause harm under normal exposure conditions;

3) Moderately dangerous (category 2) (radiance ≤4 & TImes; 106W · m-2 · sr-1): The lamp does not cause harm to the strong light and the uncomfortable reflection of temperature.

4) High risk (category 3) (radiance) 4 & TImes; 106W · m-2 · sr-1): The lamp causes harm in a shorter moment.

(2) Corresponding judgment requirements

According to IECEE CTL Resolution DSH 0744:

1) When the brightness is less than 10000cd / m2, and only visible light is emitted, there is no need to classify the hazard level according to GB / T 20145-2006. It can be classified as a non-hazardous level and can be used directly. If the brightness is greater than 10000cd / m2, it should be handled according to the method of 2) or 3) below.

2) If the manufacturer provides a test report indicating that the radiance of the luminaire does not exceed the non-hazardous and low-risk (Category 1) regulations specified in GB / T 20145-2006, the certification body can accept such an LED luminaire and consider it to be normal In this case, there is no photobiological hazard.

3) If the manufacturer does not provide such a claim, it should be tested according to GB / T 20145-2006, and the test result meets the requirements of 2) above.

4) According to the draft of IEC 62471-2 and IEC 60598-1 8th edition, LED light sources and LED lamps of category 2 and above cannot be used directly without warning signs.

4. Test data analysis

This test analyzes a product in two states, including:

Perform blue light hazard analysis on the test data of normal use LED products;

Perform blue light hazard analysis on the detection data of LED products under abnormal use conditions, that is, remove the front translucent diffuser of the lamp and perform a blue light hazard analysis;

(1) Blue light hazard analysis of LED products in normal use

The test data of normal use LED products are shown in Table 1.

It can be seen from Table 1 that under normal use, the test conclusions of various types of test samples are: Of the 27 samples, 14 samples have a blue light hazard that is non-hazardous, 13 samples belong to category 1 and no samples belong to category 2. Danger.

among them:

-LED desk lamp: There are no LED desk lamps belonging to category 2 in 8 samples, which can be safely used under normal circumstances.

-LED spotlights: 7 samples belong to category 1 and can be safely used under normal circumstances. One of the samples has a color temperature of 100,000K, which is not a white LED lighting product that can be used for lighting.

-LED downlight: 9 samples are non-hazardous.

-LED bulb lamp: 1 sample belongs to category 1 and can be used safely under normal circumstances.

-LED panel light: Both samples belong to non-hazardous category.