Study On The Push-broom Infrared Imaging System Based On Imaging Fiber Bundle

For the push-broom infrared remote sensing imaging technology plays animportant role in the high-resolution earth observation, but the internal developmentof infrared imaging technology has been baffled by the technical level of long-lineararray infrared detector, the use of line-plane-switching infrared fiber bundle toachieve high-resolution push-broom infrared imaging has been studied in thisdissertation. In this method the linear array end of the imaging fiber bundle is usedas a long-linear array infrared detector and the plane array end of the bundle iscoupled by a mature small infrared focal plane array with the single fibercorresponding to the pixel of the focal plane one by one. It can evade the difficultyto get the long-linear array infrared detector directly, and has a signally significanceto the development of our country’s infrared imaging technology. This dissertationintroduces the composition, working principle and optical system design process ofthis novel infrared optical system particularly. And the key technology, such ashigh-efficiency coupling method, system pupil matching, and image qualityevaluation method of the system has been discussed respectively. Meanwhile, theexperiments to prove the feasibility of the system have been completed. Theexpression of the system’s modulation transfer function can be used for the imagequality evaluation of other similar discrete sampling imaging system. The opticalsystem design result and method of the telecentric structure off-axis TMA foretelescope system can also be used for the design of imaging spectrometer foretelescope. The designed two structure successor coupling system have good imagequality, small size, low temperature sensitivity and loose tolerance, which couldmeet the requirements of the100%cold diaphragm matching infrared relay system.The use of the microlens arrays for infrared fiber bundle coupling could solve theproblems, such as low fill factor, coupling loss caused by the focal ratio degradation of fibers and other issues, availably. The simulation results showed that the couplingefficiency of the system could be improved by40%. The design method of themicrolens arrays is also suitable for the microlens arrays coupling with infrared focalplane arrays. Finally, the system principle-demonstrating experiment has beenaccomplished, the results of which prove that the push-broom infrared camera basedon the imaging fiber bundle is feasibility and superiority. This experiment is thefoundation for the subsequent further verification experiments.