Performance evaluation of chromaticity measurement of miniature optical fiber spectrometer

LED lighting has the advantages of long life, energy saving and environmental protection. At present, it is gradually replacing some traditional light source products and quickly becoming the new darling of the market. People in the industry are also very optimistic about the future market of LED [1]. Facing the huge domestic market, the evaluation of LED characteristics and quality is becoming increasingly important. The light intensity radiation test of the LED refers to the CIE127-1997 technical document [2] developed by the International Commission on Illumination (CIE). By measuring the spectral radiation distribution of the light source, the luminous flux, color temperature, color rendering index, dominant wavelength, color purity, etc. are obtained. Lots of parameters. The chromaticity coordinates of the light source are very important parameters. Based on the color coordinates, the color tolerance, color temperature, color rendering index, etc. can be determined to reflect the basic color parameters of the light source to be measured. The spectroscopic color measurement system is mainly used to obtain the spectral energy distribution of the light source, and the tristimulus value is obtained according to the color calculation regulations of the CIE, and the chromaticity coordinate value is obtained. In recent years, the miniature optical fiber spectrometer is particularly popular as a spectrophotometric color measuring instrument with high sensitivity and high cost performance. The miniature optical fiber spectrometer is matched with lighting devices such as integrating spheres, and the measured signal is transmitted to the spectrometer through the optical fiber, and the grating is split (color test Generally 380-780nm), and finally converted into signal display by CCD, which can realize online photometric measurement of LED [3]. However, there are few studies on the consistency of the color measurement of the micro spectrometer. The error analysis of the spectrometer and the research on the test uncertainty show that the uncertainty of the test system is affected by the spectrometer's own noise, stray light, wavelength correction, and the stability of the light source. [4], based on the analysis of the chromaticity measurement of the USB2000 + series micro spectrometer, the actual measurement performance is investigated.