The Design Of Microbolometer's Driving Circuit And Ununiformity Correction

Compared with cooled infrared detectors,uncooled infrared detectors show low cost, light weight and low power dissipation .So they been widely used in commercial and civil affairs. Uncooled focal plane array(UFPA) is the core of a microbolometer. It adopts Silicon integration technics and has following features.low cost.well linear responsibility and high dynamic range,low 1/f noise,high frame rate and potentially high sensitivity(NETD can be 0.01K in theory).So UFPA's development is the fastest and it will be booming.Based on Sofradir 320×240 microbolometer , this paper describes the design of drive circuit and infrared image process circuit. Video encoding method is also described when it comes to image display. Virtex-E serial FPGA and TMS320VC5409 DSP are adopted as hardware design platform.In ISE development environment,VHDL is used to describe the driving sequencer,sampling sequencer, asynchronous SRAM access module, interaction between DSP and FPGA, video-coding module. Above-mentioned logic design are all functionally simulated with Modelsim.Due to nonuniformity of UFPA, one-point calibration arithmetic is adopted to calibrate the offset of each pixel. DSP is used to meet real-time processing requirement.At last,this paper summarizes the flaws of system design and methods to improve them,supply the reference for the future.