| Technical support in modern high-tech war has been becoming more and more heavy, difficult and complex. And its technology system is becoming more and more complicated, the fault rate and damage rate are increasing. Facing the high-tech weaponry the evaluation can't stay on the experience and sense of the repair experts. The old fault equipment brings us inestimable difficulties and sometimes can't detect at all. Nowadays, the detecting equipment for armored equipments used in our army can only detect some index of single-type vehicle. It has complicated structure and bad universal use. In addition, when it is used, we must disassembly the optical equipment from the vehicle. Therefore, it is urgency to design and develop a set of comprehensive in-situ detecting equipment with small volume and universal use which can be fit for different indexes and different vehicles. It has great military significance.However, the detecting system using the conventional optical design has a large volume and complicated structure so that it can't meet the demand of in-situ detection . Due to the advantages such as high diffraction efficiency, special optical transform function, binary optics has been widely used in many fields such as optical sensors, optical communication, optical computation, optical disk readout and writein and laser application system. It has the bright future. The paper has succeeded in exploiting diffractive optics into the design which realizes high accuracy detection.At first, according to the property of diffractive lens, monochromatic aberration and apochromatism are corrected. The design idea of refractive and diffractive hybrid system is creatively applied in develop the collimator with large aperture and apochromatic correction. The system has many advantages such as compact structure, few pieces, high transmissivity and good achromatic property. This design scheme has the image of high quality and has practical meaning as well. It can realize the demands of light, skillful and small military equipment.In order to verify the creative design idea, the refractive diffractive hybrid system is compared with the conventional system from the aspects of modulate transmission function, spot diagram, distortion curve, aberration curve etc. From the MTF curve, we can see that as for the long focal length objective system, at the spatial frequency of 501p/mm, the average MTF of the refractive diffractive hybrid system is 0.5 and that of conventional system is 0.43. When it comes to wide angle objective system, at 101p/mm, the MTF of the refractive diffractive hybrid system is 0.89 approaching to the diffractive limit whereas that of conventional system is just 0.35.From the spot diagram, as for the long focal length objective system, the root means square diameter of the maximum spot of the refractive diffractive hybrid system is 38.8μm and that of conventional system is 80μm. When it comes to the wide angle objective system, the root means square diameter of the maximum spot of the refractive diffractive hybrid system is 40μm whereas that of conventional system is 210μm. From the distortion curve, as for the long focal length objective system, the distortion of refractive diffractive hybrid system is 0.1 % whereas that of conventional system is 0.6%. When it comes to the wide angle objective system, the distortion of refractive diffractive hybrid system is -2.5% whereas that of conventional system is -4%.From the aberration curve, we can see that for the long focal length objective system, the aberration in refractive diffractive hybrid system is 0.013mm and that of the conventional system is 0.054mm. When it comes to the wide angle objective system, the aberration in refractive diffractive hybrid system is 0.05mm and that of the conventional system is 0.20mm. From all above, we can get the conclusion that the indexes in refractive diffractive hybrid system are much better than that in conventional system.In order to locate the collimator at the very position on the vehicle that is fit for accurate detection, magnetic mechanical system is designed. It can meet the demands of measure adjustment. It can guarantee the rapid, reliable and precise detection for muli-type vehicles.Diffractive element is used in the design of collimator for the first time. The theoretical analysis and design formula are given. Besides, diffractive theory is tried to be used in long length objective. Compared with the conventional one, the optimal design is realized. DOEs are applied to design the wide angle objective and the theoretical design formulas are deduced .Then a design example is discussed in detail.In this paper, the nonlinearity problem of CCD is analyzed then the reason is found. In addition, the approach to correct nonlinearity is put forward in detail, which guarantees the accuracy of the measurement.In order to ensure that the collimator designed by diffractive optics can be used as the standard instrument to detect the military optical equipments, we demarcate the collimator at the quality test center of Changchun institute of optics, fine mechanics and physics Chinese academy of sciences. In the process of demarcating, a standard collimator whose focal length is 1600mm, aperture is 160mm,resolution is 8×10-3 is adopted. The demarcating result shows that the real focal length is 500.40mm, the angular resolution is 1.72".What is more, the influences of adjustment error of collimator, measurement error of CCD and non-measured signals on the measurement result are analyzed. On the basis of collimator demarcating and error analyzing, various indexes of the vehicle borne optical equipments are in-situ detected. The test results show that the detecting system is able to detect various indexes of optical equipments on armored vehicles rapidly and accurately. It is the first time that the comprehensive non-disassembled in-situ detection for vehicle borne optical equipments has been realized.
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