Screening of LED for spectrum-tunable light source

In order to meet the requirements for lifetime and spectrum consistency of LED used in LED-based spectrum-tunable light source, 29 kinds of LEDs were seasoned for 200 hours separately under the accelerated current condition, and a spectral consistency screening algorithm was proposed. Results of ageing test indicate that the values of radiant flux attenuation of 3 kinds of LEDs, whose peak wavelengths are 385 nm, 400 nm and 420-1 nm, are 24.8%, 10.7% and 25.6%,respectively, so they are not suitable for LED-based spectrum-tunable light source. The values of radiant flux attenuation of the remaining 26 kinds of LEDs are all below 3.5%, and they are all suitable for LED-based spectrum-tunable light source. The spectral consistency screening algorithm is based on the LED-s spectroscopic data, and the relative spectral deviation among the same kinds of LEDs can be calculated. The relative spectral deviations of 26 kinds of LEDs are all below 4.5%, the spectral consistency of the screened LED can be ensured.