A colorimeter is an instrument that determines the amount of light that passes through a solution in comparison through a pure solvent. A photocell in the colorimeter detects the amount of light passing through the solution and converts it into an electrical signal. Light absorption and the current produced by the photocell is increased by higher concentrations and colors. - Built-in white plate parameters. No need to calibrate each time which can perform measurement quickly. - Double Locating: Illuminating locating and precise cross locating. - Switchable Double Measurement End Face: Large stable end face and small concave-convex end face. - New 45°/0° Optical Path Design: Significantly improve the measurement stability and precision.