Substance detection method and apparatus, and detection device

A detection terminal, comprising a light source and a lens component, wherein the lens component is used for collecting light emitted by the light source and collecting the scattered light of the light through a substance to be detected, so that the detection terminal obtains the spectral information of the substance to be detected according to the scattered light;

• and the detection terminal further comprises:
• a camera component used for taking a picture of the substance to be detected, so that the detection terminal obtains the image information of the substance to be detected;
• wherein the lens component comprises a first fixed focus lens, the camera component comprises a second fixed focus lens;
• and the distance between the first fixed focus lens and the second fixed focus lens is represented as a, the fixed focal length of the first fixed focus lens is represented as d, then the installation angle of the second fixed focus lens is α=arctan (a/d), and the fixed focal length of the second fixed focus lens is f=√{square root over (a2+d2)}.