A photometer is a kind of measuring instrument of light and color.
Photometer meter is one of the necessary instruments in the laboratory, which has been widely used in various quantitative and qualitative analyses.
Principle of Photometer:
The photometer mainly uses a pair of light holes with a certain distance to receive the light flux with a fixed solid angle and a fixed projection area. This value does not change with the distance of the object, as long as the surface area of the object is large enough. In order to aim at the measured object, an imaging system is often used. After passing through the objective lens, the light source is imaged on the mirror with a hole (front light hole). Part of the light source is received by the human eye through the mirror and eyepiece, so as to aim and monitor the clear imaging surface, which coincides with the aperture mirror. The other part of the light passes through the small hole in the mirror and then reaches the V (λ) receiver through the back-light hole. The brightness value is displayed by pointer or digital meter.
Features of Photometer:
1. Use a microcomputer to control and process data.
2. The interference filter is used as the beam splitting element, and the photoelectric conversion is carried out by the photoelectric tube.
3. It has functions such as the direct reading of potassium as well as sodium concentration, curve fitting, sensitivity drift, automatic correction, automatic full adjustment, display of operating errors, printing results, and so on.
4. It has good linear stability and reproducibility, especially suitable for clinical application.
Application of Photometer:
Photometer is commonly used in lighting engineering, light source and light-emitting devices, film and television, traffic signal, architecture, atmospheric photometry, and other fields.