Aiming at the design requirement of miniature reflective optical system,a new type of off-axis three-mirror anastigmat (TMA) and freeform surface are adopted, the F#1.8,and diagonal field of view7.5° is realized.Light overlap many times within the optical system,the full field average RMS Wavefront abberations is 0.017λ(λ=10μm). Compared with other optical system, the new freeform TMA has small size, high transmittance, large field of view, large relative aperture, no centered obscuration, low stray, radiation, wide spectral band, etc.
A linearization double-group linkage zoom lens was presented based on the 640×512 cooled FPA. This configuration’s zoom groups and compensate groups are moved linear zing, omit zoom cam which control the movement of zoom curve make common double-linkage zoom lens easily. This configuration is similarity to optical compensate zoom has a little image displacement, but it is not influence the image quality when the image displacement control in allow range. This lens was placed at cold shield and 100% cold shield efficiency had reached. Moreover, detailed design and image quality were given by CODE optical software. After analysis, MTF approaches diffraction limit. The results show that this optical system has large zoom ratio, and excellent image quality.
In this paper, we put forward a new method to adjust the air gap of the total reflection air gap of the infrared Pechan prism. The adjustment of the air gap in the air gap of the Pechan prism directly affects the parallelism of the optical axis, so as to affect the consistency of the optical axis of the infrared system. The method solves the contradiction between the total reflection and the high transmission of the infrared wave band, and promotes the engineering of the infrared wave band. This paper puts forward the method of adjusting and controlling, which can ensure the full reflection and high penetration of the light, and also can accurately measure the optical axis of the optical axis of the different Pechan prism, and can achieve the precision of the level of the sec. For Pechan prism used in the infrared band image de rotation, make the product to realize miniaturization, lightweight plays an important significance.
In order to project the laser command information to the proper distance , so a laser zoom projective lens with variable total track optical system is designed in the carrier-based aircraft landing system. By choosing the zoom structure, designing of initial structure with PW solution, correcting and balancing the aberration, a large variable total track with 35~× zoom is carried out. The size of image is invariable that is φ25m, the distance of projective image is variable from 100m to 3500m. Optical reverse design, the spot is less than 8μm, the MTF is near the diffraction limitation, the value of MTF is bigger than 0.4 at 50lp/mm.
A visible, MWIR, long focal, oblique view and focusing optical system of aerial camera is described, and in this paper we design an innovative optical system with common optical path and catadioptics configuration. The focal length of this optical system is 1.45m in the visible waveband (0.7~0.9μm,) and 0.61m in MWIR waveband (3.7~4.8μm), and the oblique view scanning range is within 20km~100km. To meet the requirements for the sharp imaging quality under the circumstances of high altitude environment and real time variable range, this aerial camera is focused by making back cutoff length longer to add a mirror, then MTF of optical system is all above 0.4 in Nyquest frequency.
A 15× double-group linkage zoom lens was presented based on the 640×512 cooled FPA. Having two alternate components linked and moved together, double-group zoom structure has smoother cam curve, so the displacement of all components are smaller and the total length is shorter. The focal length rang is 30~450mm and wavelength is 3.7~4.8μm, F number is 4. This lens was placed at cold shield and 100% cold shield efficiency had reached. Moreover, detailed design and image quality were given by CODE V® optical software. After analysis, MTF approaches diffraction limit. The results show that this optical system has large zoom ratio, and excellent image quality.