Test System Of Spectral Transmission Base On The Correlation And Amplification Principle

Spectral transmittance is that the radio of transmitted beam luminous flux and incident luminous flux,and it is an important index of the energy transmission of optical systems.In addition to optical properties and image quality,spectral transmittance is another important performance index in optical systems, because the magnitude of spectral transmittance affects the level of imaging signal-to-noise ratio, spectral transmittance measurement of optical systems has the crucial important significance. Detection methods of spectral transmittance of optical system are limited the spectral range a certain extent at present, and because the interference of background noise can not be avoided, testing have to be achieved in the darkroom,then it puts forward demand for the test conditions.And non-measurement and actual measurement all were performed in the single channel detection system, so it can not guarantee the consistency of the light source intensity, these lead to more testing error.Using that the double grating monochromator emits the awaiting measurement light of the corresponding bands,and lock-in amplifier has a very strong capability of weak signals detection,so this paper presents a detection method of spectral transmittance of optical systems with double channels detection system base on the correlation and amplification detection principle.And it not only can satisfy the spectral detection of multiple bands,but also suppress effectively the interference of the background light, In order to achieve the detection in the bright field, increase the detection precision and reduce the requirements of testing environment.