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FPA Imaging Quality Analysis And Optimization Technology Study

Posted on:2006-02-07Degree:DoctorType:Dissertation
Country:ChinaCandidate:Y ZhangFull Text:PDF
GTID:1100360185491822Subject:Optical Engineering
Abstract/Summary:PDF Full Text Request
Infrared thermal imaging technology transforms infrared radiation distribution of the natural scene into visible image, it overcomes not only the shortcomings of active infrared night vision's needing of man-made infrared radiation source, but also the shortcomings of passive low light level night vision's depending on natural light. With the development of infrared Focal Plane Arrays (FPA) technology, especially uncooled infrared FPA technology, thermal imaging technology plays more and more important roles in military affairs and national economy. Just as array imageing devices such as visible light CCD, during the imaging process of staring infrared FPA, spatial-sampling frequency is determined by spatial distance of detecting unit. While spatial frequency of the detected scene is always more than half of the sampling frequency of staring infrared Focal Plane Arrays, thus under-sampling happens, and the quality and utility of the image are seriously degraded by aliasing. On the other hand, the spatial resolution and thermal sensitivity of uncooled infrared FPA image is realitively low for recent technology, the application of infrared FPA technology is restricted to some extent.For this reason, an integrated novel theoretical analysis named Phase Theory Model of Spatial Sampling Array Imaging is put forward, and a theory foundation is provided for study and test of staring infrared Focal Plane Arrays and the reduction of the aliasing effect. As applications of this theory model, microscan and uncontrolled microshift superresolution technology is theoretically discussed; a kind of nonmechenical microscan technology based on infrared TFT-LCD is put forword and designed through the study of routine mechenical microscan technology and the spectrum and electro-optical characteristics of liquid crystal.In addition, while studying FPA spatial-sampling imaging, we noticed that some kinds of array display systems such as full color large scale LED display and handset digital video apparatus can't meet the need of high resolution for various reasons. Triangle pixel regroup and square pixel regroup virtual pixels technology based on array display pixels reformation are put forword under the guidance of phase theory model of spatial sampling array imaging, and over-sampling super resolution display on under-sampling structure condition is realized.In infrared image real-time processing, on the base of IRFPA thermal imaging system...
Keywords/Search Tags:infrared focal plane array, spatial integral sampling, central brillouin zone, aliasing, microscan, super resolution, self adaptation, temperature window adjustment, two dimensional time delay integration(2D-TDI)
PDF Full Text Request
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