Design Of Optical Path Controlling System For Single Photon Time Resolved Imaging Spectrometer

Frontier science and hi-tech industry have an increasingly higher demand for observing the key material producing and transferring process of transient and extremely weak optical signals. The traditional spectroscopy and imaging techniques are important means of understanding the objective world, but they are unable to meet the current demand of scientists. The single photon time resolved imaging spectrometer becomes the urgent needed high-end instrument in the current frontier science research field. It innovatively solves the dimension and sensitivity problems by combining compressive sensing theory and single photon detection technology. It is a new generation of high performance optical instrument based on new principle. With the development plan of single photon time resolved imaging spectrometer proposed, the development requirement of subsystems and key components arises naturally.The optical path controlling system designed in this dissertation is the core technology of this instrument, and it is used for implementing the measurement process of compressive sensing theory. It realizes the binary random measurement matrix with a DMD (Digital Micromirror Device) which modulates the light and converges it to the single photon detector. The controlling system plays a key role in the instrument by connecting the optics and electronics.Firstly, the DMD controlling system overall architecture based on FPGA is proposed in this dissertation. It consists of a DDR2 SDRAM application interface and a DMD controller. The DDR2 SDRAM application interface provides high speed data flow for DMD and the DMD controller realizes binary showing with DMD.Secondly, a customized DDR2 SDRAM application interface is designed for DMD based on the system overall architecture. This interface greatly simplifies the user’s operation. It can be operated with just a single signal line without complex operation commands. The application interface will synchronize data and commands automatically.Finally, a specialized DMD controller is designed for compressive sensing. Based on DMD interface chip DDC4100, the controller can achieve the most convenient operation. A single signal line is available to accomplish all the process of showing operation. The controller will automatically read data from DDR2 SDRAM interface and transfer them to DMD for binary matrix showing.The experimental results show that this system realizes the binary matrix. It provides a technology platform for compressive sensing measurement process in the spectrometer.