LED light source black reason
1. Vulcanization, chlorination, bromination
LED brackets on the silver-plated layer of sulfur-containing gas will produce silver sulfide, contact with acidic nitrogen, bromine gas will produce light-sensitive silver halide, which will lead to light failure. Light source sulfur / chlorine / bromide in the LED light source and lamp production, storage, aging, the use of each link are likely to occur. In the light source is diagnosed as sulfur / chlorine / brominated, the customer should be based on sulfur / chlorine / bromine generation of the link, select the specific sulfur removal program. At present, the sulfur / chlorine / bromine test items introduced by Jinjian are: sulfur / chlorine / bromine (including built-in power supply), brine / chlorine / bromine (except external power supply), power supply sulfur / chlorine / bromine Desulfurization / chlorine / bromine, packaging workshop drainage / chlorine / bromine, lighting workshop sulfur / chlorine / bromine, reflow shop waste / chlorine / bromine. As the sulfur / chlorine / bromine gas will penetrate through the silicone or stent into the light source inside the internal, so Kam Kam has also introduced a gas tightness inspection program to further help customers improve the light source requirements.
Silver in high temperature and humidity environment, will easily react with oxygen, generate black silver oxide. Jin Jian in the diagnosis of light source black reason for the oxidation of silver-plated layer, the customer will be recommended to do further light and light insulation inspection, the eradication of moisture penetration.
In order to talk about experience, LED light source six raw materials (chips, stents, solid crystal, bonding wire, phosphor, plastic packaging) material defects and 3 large packaging process (solid crystal, wire, irrigation) process defects Are likely to cause the light source to produce a very high temperature, resulting in partial or overall black light source, light source carbonization. LED lighting cooling design is unreasonable, thermal conductivity of low thermal conductivity, power supply design is unreasonable, reflow defects can also cause too much light source carbonization. Therefore, when the primary diagnosis of light source is the reason for carbonization, it is recommended that customers take LED light source or lamp failure analysis route, the light source / lamp anatomy, identify defects or high thermal resistance sources.
4. Chemical incompatibility
The lightening of the LED light source may also be caused by contamination of the chemical, which often occurs in sealed lamps with little or no air flow. When the diagnosis of light source is caused by chemical compatibility problems, will be recommended for customers to use the materials used in the lighting incompatibility of the investigation to find out the material is not compatible with the light source. Often encounter problems. However, the black light is only appearance, vulcanization, chlorination, bromination, oxidation, carbonization and chemical incompatibility and other reasons will lead to LED light source black phenomenon. Due to the lack of professional testing equipment and personnel, most of the LED companies to do blacking failure analysis is usually based on experience and guess, the lack of scientific test data. In response to this phenomenon, Jin Jian launched LED light source of the initial diagnosis of the business, aimed at 2 days to help customers quickly, low cost, accurate qualitative LED light source blackening reasons (in the end is vulcanization, chlorination, bromination, oxidation , Carbonization, or chemical incompatibility), and according to the LED light source blacking failure analysis roadmap to provide customers with further solutions to identify the problem.