When imaging with white light, in addition to the five kinds of monochromatic aberrations produced by each monochromatic light, the dispersion caused by different refractive index of different colored light will also cause different propagation light paths of different colored light, thus showing the aberrations caused by different light paths of different colored light, which is called chromatic aberration (color aberration for short). The chromatic aberration can be divided into position chromatic aberration and magnification chromatic aberration.
Raw material powder (flour, starch, rice flour, salt, textile, printing and dyeing, chemical fiber, plastic, porcelain clay, talcum powder, white cement, paint, paint, ceramics, enamel, paper, pulp, etc.) needs to control the whiteness of the product. Sometimes in order to control the quality of the same batch of products or different batches of products, in addition to testing the whiteness of the pigment, it is also necessary to use the instrument to assist the analysis to control the color difference, so as to ensure the controllability of the color of different batches of products.