* It is composed of light source, optical system, detection system, data processing and display system. The whiteness calculation of this instrument is blue light whiteness R457 * Define the whiteness value of an suace with a diffuse reflectance ratio of 1 across the visible spectral range as 100, and the whiteness of a black suace with a spectral reflectance factor of 0 as 0 *Diffuse reflection is the reflection of light projected on a rough suace in all directions. When a beam of parallel incident light is emitted to the rough suace, the suace will reflect the light in all directions, so although the incoming rays are parallel to each other, because the normal direction of each point is inconsistent, causing the reflected light to reflect irregularly in different directions, this reflection is called "diffuse reflection" or "diffuse.Shoot " * USB, RS-232C data line output and PC connection, data collection