Papers by Keyword: Optical Design

Abstract: Aerial cameras are widely used in resource surveys, topographic mapping, military reconnaissance and many other fields. This paper introduced the sort of aerial camera, the development in our country and abroad about the theory of secondary spectrum. In order to meet the requirement for simple structure and high-resolution, the optical design of the apochromatism objective lens of aerial camera is achieved by common optical material. Objective’s focal length is 400mm, relative aperture is F/4 and work waveband is 420nm~850nm. Designing results show that the MTF of every field above 0.75 in 60lp/mm and satisfy the requirements of imaging for large frame array CCD whose effective size is 36mm×48mm.

Abstract: As for the requirement of size and energy distribution of focal spot in the laser detection area, this paper designs a laser beam-shaping system of flow cytometry. The 640nm red diode laser and 488nm blue solid laser which are arranged vertically are used as the excitation source. The emergent ray of two lasers is combined by beam splitter, and the combined beam is focused on the screen through two orthogonal cylindrical lens. The focal spot is compressed by doublet lens which is also used to eliminate chromatic aberration of focal spot. Applying ZEMAX software to optimize the whole optical system, the simulated results meet fully the actual experiment for individual blood cells, and it has certain theoretical significance for actual design of optical system about flow cytometry.

Abstract: The system of achromatic phase matching (APM) based on grating pairs is designed by the commercial optical design software ZEMAX. Firstly, we theoretically calculate the theoretical incident angular where each frequency components exactly reaches the phase-matching in nonlinear crystals. Subsequently, the model of APM system is built and optimized in ZEMAX. The results are well in accordance with the theoretical ones. In addition, the effects of grating frequency and aberration produced by the focus lens on APM scheme are analyzed.

Abstract: Based on the principle of passive optical athermalization, a wide field medium wave infrared optical system is designed for working at -40℃-60℃. A 320×240 focal plane array (FPA) detector as image plane is used in the system. The system has a field-of-view of 30°×22.72° and a relative aperture of f/2 at 3-5 µm with 100% cold shield efficiency. The modulation transfer function (MTF) of each field is greater than 0.6 at the Nyquist frequency and the maximum distortion is less than 3% at -40℃-60℃. The system can meet the demand of the excellent image quality. This work is valuable for athermalization design of wide field medium wave infrared optical system.

Abstract: In this research, a contact lens design for myopia and astigmatism eyes was proposed. With two spherical surfaces assembled in the optical system, the design could take advantage of compacting overall volume size. But in this design, the value of spherical aberration (SA) at wide radius of contact lenses seems lower. If we corrected the design to improve the value of SA, Modulation Transfer Function (MTF) and coma aberration (TCO) value would become lower relatively. In this study, we integrated the Taguchi method and principal component analysis (PCA) to optimize the multiple quality characteristics (SA, TCO and MTF) of the contact lenses. With the combination of the methods, a set of optimum design parameters was well selected to balance the values of SA, TCO and MTF that improve the SA 25.63%, TCO 91.88% and MTF 2.4%. It was concluded that the integration of the Taguchi method and PCA succeeded in optimizing the SA, TCO and MTF values, and the contact lenses could be well designed without sacrificing system performance.

Abstract: With the development of the high resolution micro display device and the virtual reality technology, head mounted display is now going to a commercial age. And the products of their own are also put forward to some special requirements: small volume, light quality, simple operation, object popularity. As the requirements at a suit, it needs excellent optical system design, electronic system design, structural design and many other fields together. In order to solve this problem, we use the software designer Zemax and compact a portable structure optical system, combined with 3D imaging hardware decoding technology, preliminary design a set of glasses declined display system. The system has a watching feeling as you see a 80 inch screen at 3 meters away.

Abstract: A new optical structure design method was proposed by forward-object lens, zoom lens, focus lens and behind-object lens with transmissive switch-zoom infrared system. And an alignment method of the above structure was proposed to assure the imaging precision. The larger caliber forward lens structure was designed to immovably axial with system axis, while the zoom lens structure was designed to three different structures by actual optical design for reducing system dimension. The focus lens structure was absolute configuration for the stabilization during focus. The rear lens structure was also designed to small radial clearance. A through-shaft type tooling was proposed to cooperate to adjusting and confirming of the system optical axis by exact boring machine. Experiment results showed that the alignment method can be assured precision and economized cost.

Abstract: Objective lens is the core part of a collimator, its quality has a direct impact on the collimators quality. Due to the small field of view and low image quality requirement, general collimator objective lens is difficult to achieve the requirement of testing an aerial camera s performance. So designing a large field of view, apochromatic collimator objective lens has an important practical significance. In this paper, the major qualifications were first proposed to design the collimator objective lens,according to which the initial configuration was confirmed. Then we used the ZEMAX optical design software to optimize the initial structure and normalized the optimized structural parameters. Finally the image quality of collimator objective lens was evaluated to make it achieve the requirement of qualifications.

Abstract: The diffractive optical elements, with the negative dispersive characteristic and the random phase distributing to realize random phase modulation for wave-front, are not only helpful to simplify the optical system, but also improve the image quality, while putting it into the optical system. It can decrease the element numbers of the system and obtain a compact configuration that introducing diffractive optical element into the design of eyepiece. A hybrid diffractive-refractive wide-angle eyepiece, with a big exit pupil distance, is designed by using the Code V Optical Design Software. The features of the wide-angle eyepiece are 30mm effective focal length, 60°whole field-of-view (FOV), 30mm exit pupil distance and 6mm exit pupil diameter, and which consists of four lens and two diffractive elements. From the result of design, the MTF in the center field of the wide-angle eyepiece is over 0.55at 60lp/mm, at the same time, the MTFs in all fields are over 0.3 at 50lp/mm, which show that this wide-angle eyepiece has a great image quality.

Abstract: Endoscopic telecentric apparatus is a precision measuring instrument which consists of optical, mechanical and electrical technologies. It can be applied in real-time accurate test to detect the position, shape and wall surface defects of brake master cylinder. This paper designed an optical system with Zemax, it can be used in endoscopic telecentric apparatus. The system has 4mm linear field of view, the line of vision is 90°,the magnification is 0.75×,the depth of field is 6mm.The value of modulation transfer function (MTF) is close to the diffraction limit, the resolution of the system is up to 3 and the spot diagrams of all configurations are smaller than Airy disk, the total track is less than 300mm. It adopts 1/6CCD to receive image, the measurement accuracy reaches to 0.03mm.The system uses pentagonal prism to realize 90°line of vision, it is convenient to assemble and avoids the mirror image. The image quality is good and the design meets the requirement.