| In order to apply the near infrared image acquisition technology to photo elasticmodulator-imaging spectro polarimeter (PEM-ISP) to get high quality spectrum, polarizationand image information. To improve the integrity and data collection, transmission speed ofimage data in the process of collecting the near infrared camera data. This paper introducesthe near infrared image acquisition technology based on FPA-640x512InGaAs focal planearray detector, used in the photo elastic modulator-imaging spectro polarimeter (PEM-ISP).Due to the field-programmable gate array (FPGA) process digital information usingparalleling. Using FPGA to realize the detector’s sequential control, can meet the highprecision requirements of the system, and design is flexible, the portability of program andmodule is strong. Therefore, the system adopts FPGA as the signal processing unit, achievethe rapid acquisition and parallel processing of the optical signal, satisfy the requirements ofthe high speed, real-time signal transmission and processing technology, etc. To adopt theFPA-640x512InGaAs focal plane array detector in receiving element of the optical detection,the data will be collected by the A/D and stored in Static RAM (SRAM) that is FPGAextended. Using two pieces of SRAM as data buffer module, through the mutual cooperationof the selection module of input data and output data, the buffered data flow is sent to theprocessing unit with on time to stop, to ensure the integrity of the data flow. Finally the data issent to the PC through the Universal Serial Bus (USB), the PC achieves image reduction byLabVIEW software.Results of the experiments show that the system can be applied to the photo elasticmodulator-imaging spectro polarimeter (PEM-ISP), realize the precise detection andacquisition of the measurement signal. Greatly improve the speed of the data cache, realize seamless processing and transmission of the data, get the full spectrum, polarization andimage information. |
