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This paper overviews the research situation and development prospects of artificial compound eye optical systems on the basis of their advantages of small volumes,light weights,large field-of-view and high sensitivity.It introduces the structures and classification of insects′ compound eyes,and describes the research development of artificial compound eyes according to the design of artificial imaging systems with curved and plane surfaces.Then,it gives structures,models and imaging abilities of typical compound eye imaging systems at home and abroad,and summarizes their usages and merits in different fields.Finally,the preparing techniques of artificial compound eyes are analyzed.Analyzed results point out that the functions of compound eye optical systems are dependent on the fabrication of the microelements,the super fine machining is a fine and effective micromachining method and it has the potentials to fabricate higher accuracy lens arrays and improve application abilities.

In order to overcome the shortcoming that the luminous flux of the classical spectrometer is small due to the occlusion of the entrance slit,a design concept of the new kind of Hadamard transform spectrometer is proposed.A method of shaping the beam by a cylindrical lens is given.Using theoretical calculations of the spectral resolution ability and the pixel resolution ability of the spectrometer,containing a digital micromirror array,he limit class of the spectrometer resolution can be determined.Based on the geometric theory of optical imaging,an optimization program of the more focal length of the imaging lens is proposed,which is able to obtain the higher spectral resolution and the more beneficial to the mechanical alignment.The advantages of the new Hadamard transform spectrometer are that it has a high luminous flux,the signal-to-noise ratio is 5times more than that of traditions,and the smaller spectral bandwidth is 3.5nm,providing convenient conditions for the detection of weak spectral signal.In addition,the near-infrared detector selected by the spectrometer needs no refrigeration,which will cut the production costs of the Hadamard transform spectrometer,with a stronger market competitiveness.

An optical method for the nanogap measurement beyond the optical diffraction limit was reported.The function relationship between the nanogap width and the phase difference was built.Based on the high sensitivity of a surface plasmon resonance(SPR) sensor,the nanogap width between a light transmitting mirror and a reflector could be measured by detecting the phase difference between p-and s-polarizations of the light.Numerical simulation shows that the phase difference shifts from 150° to-150° by changing the nanogap width from-0.5 to 0.5 μm and the measured sensitivity of nanogap width is better than 1 nm.This nanogap measurement method can realize the measurement for the smallest gap below 10 nm and provides a simple and real-time operation beyond the physical diffraction limit.

In order to improve the imaging quality of coronagraphs,the ghost image caused by multi-reflection light from an objective lens for the internally occulting refractive ground-based coronagraph is analyzed at a band from 530 nm to 555 nm.The coronagraph with an aperture of 120 nm shows its main specifications in a field of view of 1.1 to 3R⊙,a resolution of 13.5 μm,and F number of 8.2.The paper analyzes its imaging theory and establishes a model for the ghost image.Then,it presents the structure masking measures and performs an experimental demonstration.The experiment result shows that the masking structure is effective on the elimination of ghost image.In addition,the intensity of ghost image and the intensity of diffracted light of objective lens edge are basically the same.The experiment also illuminates that the size of ghost image is the same as the simulation result of 0.9 mm.The ghost image suppressing further improves the capability of elimination of stray light and the image quality of the coronagraph achieves the effective observation of the solar corona.

A lens for a Light Emitting Diode(LED) rear turn lamp of motor vehicles is designed to increase the accuracy of light distribution and energy efficiency of the lamp.According to the nonimaging optical principle and Snell′s law,the lens design is obtained by an iterative solution,and the height and the diameter of the lens are 8.32 mm and 12.64 mm,respectively.By using the optical software TracePro,the LED and the lens of rear turn lamp are traced and simulated.The results show that in a rectangular range from-80° to 80° in the x direction and from-80° to 80° in the y direction,the luminous intensity is greater than 1.6 cd.Moreover,in the rectangular range from-20°to 20°in the x direction and from-10°to 10°in the y direction,the luminous intensity distribution is approximatly rectangular,and the luminous intensity of each test point meets the requirements of GB17905-2008.The lens can control the LED light precisely,which is beneficial to improve the performance of the light distribution and energy efficiency of the rear turn lamp.

In order to make a comprehensive evaluation on a head mounted display(HMD),a simple and feasible testing method is proposed and an optical system for the test is specially designed.According to the requirement of pupil engagement for the HMD and the testing system,a structure of eyepiece is adopted in the optical design,and a plastic aspheric lens is used to realize the distortion-free property.The designed optical system has a field of view of 50°,a pupil size of 4 mm and a distortion less than 0.1%.It can keep high performance when the testing HMD is with diopter from-4 D to 3 D.The analyses on the design show that the evaluation system can satisfy the evaluation requirement of HMD with various diopters.

To solve the problem of poor roughnesses for heavy curved freeform surfaces in prism processing,a Head Mount Display(HMD) prism with decentered aspheric surfaces was developed.All the optical surfaces of the prism were rotationally symmetrical aspherics,which showed a better processing property as compared with freeform surfaces.A short focal length and a large field of view were obtained by controlling the surface curvatures and tilt angles,and the aberration was corrected by optimizing aspheric coefficients.Experiments show that the HMD prism has an exit pupil of 6 mm and a field of view of 55°.At the frequency of 30 lp/mm,the axial Modulation Transfer Function(MTF) is over 0.2,the off-axial MTF is over 0.1,and the maximum distortion is-5.37%.The test and experiment on the prism demonstrate that the surface roughness has been greatly improved to a lower level for the aspheric surfaces,which avoids the image blurring and improves the performance of visualization.

According to the evaluation indexes of road lighting,the light distribution of Light Emitting Diode(LED) luminaries was optimized.A mathematical model of the illumination distribution for LED luminaries was established based on the relationship between the evaluation of road lighting and the illumination distribution.By taking the evaluation indexes of road lighting as the optimization conditions and the ratio(Q) of average luminance to average illuminance of road surface as an optimization target,the light distribution was obtained by solving a constrained optimization problem.Finally,the optimized light distribution was induced into lighting simulation software to simulate the LED luminaries for an asphalt trunk road.The result shows that the light distribution is asymmetric in the lateral direction,and the maximum intensity direction leans to the traffic lane.The light distribution saves 30.3% in energy consumption compared to traditional symmetrical light distribution.Moreover,the Q value is 0.072 7,which is higher than that of the normal asphalt trunk road.The evaluation of the road lighting meets the standard of CJJ 45-2006,and demonstrates that the lighting parameters are optimized well.

In order to achieve full light utilization and satisfy the demand for far-field illuminance of LED,automated optimization method in sequential mode of ZEMAX was proposed in the design of collimator with far-field illuminance for LED source.The system was established in ZEMAX′s multiple configurations,and the user defined merit function was written out using ZEMAX Programming Language(ZPL) macros language.In the simulation,the material of lens is PMMA and the source is Lambertian-type LED light source,of which divergence angle is 180°.Optimum parameters of collimator were obtained via running an optimization.The optical simulation results show that an efficiency of 87% is achieved under a view angle of ±0.1° and for a point LED source.