First of all, LED chips have BIN and gear differences. Different BIN and gear need to be mixed according to regulations, otherwise there will be color difference and other undesirable conditions. The BIN and BIN color mixing schemes of particles produced by different companies are also different. It depends on the BIN color mixing scheme provided by the light source supplier. When you can’t mix BIN, it is recommended to use a single BIN.
Let’s talk about BIN first. BIN is actually a relatively abstract concept. In life, humans evaluate color consistency. White has beige, pure white, and milky white, and green has dark green and light green. For LED chips, the same 3,000K color temperature will have different colors from different light sources.
In the process of light source selection, light color and electrical tests will be carried out to obtain color coordinates. The color coordinates fall at different positions on the MacAdam ellipse, and the color will be different. For example, although the red dots in different areas of the 3000K MacAdam ellipse belong to the 3000K range, the human eye can still find the difference in color. Therefore, the light source supplier will divide the entire 3000K range into multiple areas, such as the four areas ABCD in the figure above, which become four different BINs. For example, the five red dots (color coordinates) in the figure above fall into different partitions.
Next, let’s talk about the gear. Generally, the gear is determined according to the chip difference of the light source itself. The more common classifications are voltage/current gear and lumen gear (luminous flux gear). In the process of light source packaging production, large factories have huge output and cannot guarantee that the same products produced at the same time have the same voltage, current, and luminous flux output. Therefore, after the packaged products are produced, they will go through a process called “optical selection”, that is, the light source is classified using an optical sorter. The classified light sources will be divided into multiple categories, namely “gears”, according to different voltages, currents, and luminous flux outputs.
For example, the common light source gear subdivision (no practical significance, for reference only):
Gear A: voltage 2.9-3.0V, luminous flux 21-23lm
Gear B: voltage 3.0-3.1V, luminous flux 23-25lm
Gear C: voltage 3.1-3.2V, luminous flux 25-27lm
In simple terms, it is to subdivide the color temperature partitions so that the color of the light source in the same color temperature partition remains highly consistent.