###### Abstract  
In this paper, a method of color discrimination based on sample sensitivity to light wavelength is proposed based on the reflection spectra of a large number of samples and the statistical calculation of the measurement data. A laser detection system is designed to realize the color discrimination. For the color discrimination of polycrystalline silicon cells, the most sensitive wavelength, 434 nm, and the least sensitive wavelength, 645 nm, of polycrystalline silicon cells is obtained according to this method. A laser detection system was built to measure the polycrystalline silicon cells. This system consists of two lasers, optical shutters, collimating beam expanding systems, an optical coaxial system, sample platform, collecting lens, and optical power meter or optical sensor. Two laser beams of different wavelengths are beamed coaxially through the optical coaxial system onto a polycrystalline silicon cell and are reflected or scattered. The reflected or scattered lights are collected through a lens with a high number aperture and received separately by the optical power meter. Then the color value of the polycrystalline silicon cell in this system is characterized by the ratio of light intensity data received. The system measured a large number of previous polycrystalline silicon cells to form the different color categories of polycrystalline silicon cells of this system in the computer database. When a new polycrystalline silicon cell is measured, the color discrimination system can automatically classify the new polycrystalline silicon cell to a certain color category in order to achieve color discrimination.  
color discrimination; laser detection  
namely the ocular estimate method, the color discrimination system based on imaging technology, and the color discrimination system based on spectral technology.  
The ocular estimate method is a traditional method of color discrimination. The specific method is that standard chromaticity observers visually identify objects under specific lighting conditions and compare them with the CIE (Commission Internationale de L'Eclairage) standard chromaticity diagram to obtain color parameters. The research on the chromaticity diagram dates back to as early as the beginning of the 20 th century when [PERSON] [2] proposed the color system of the same name. Subsequently, many color systems were developed, including the CIE standard chromaticity diagram [3] that has been widely used since 1931. But the main problem with the ocular estimate method is that it relies entirely on the human eye to recognize color differences. This is a drain on the human eyes, and recognition results are affected by individual differences and fatigue. In 1839, [PERSON] invented the camera, which laid the foundation for color discrimination system based on imaging technology. This method mainly analyzes object color based on imaging photos, and the analysis principle is mainly based on RGB color model. A color image of a number of objects in an unknown light condition that automatically computes a certain transformation in order to obtain the color parameters of each object in the scene under a certain standard or known light. The color discrimination system based on spectral technology obtains the color parameters by analyzing and converting the reflectance spectral information of the object under different wavelengths of illumination.