Design and implementation of CCD imaging circuit for airborne ultraviolet DOAS imaging spectrometer

Airborne ultraviolet imaging DOAS (Differential Optical Absorption Spectroscopy) spectrometer monitors the distribution and changes of atmospheric trace gases by obtaining the UV radiation of atmosphere and surface reflection or scattering. In this spectrometer, the CCD imaging circuit is the core of electronic device. A complete system was designed and implemented by using frame transfer area array CCD-47-20. Field-Programmable Gate Array (FPGA) was adopted as the core controller of the CCD imaging circuit, which generated CCD driving sequences, CCD data acquisition, received and converted CCD analog imaging signal to digital signal. CCD digital imaging signal was drove by differential line driver and then acquired by the airborne communication system in low voltage differential signaling (LVDS) format. The design and implementation of the circuit was described, and the design process of the CCD imaging circuit was mainly discussed. The imaging resolution of airborne ultraviolet imaging DOAS spectrometer monitoring is 0.286. The experiments show that the requirements of polluting gases observation can be satisfied.