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For the advanced light source including Free Electron Laser (FEL) and Synchrotron Radiation Facility, X-ray mirrors are very important component for X-ray transport in beamlines. The surface quality requirement on the mirrors for the Free Electron Laser (FEL) or for diffraction-limit application has been studied by many researchers. In this paper, the mirror quality specification in non-diffraction limited case is studied for the partial coherence light source. Simplified model for the beamline system is given and compared with other numerical simulation software. Then, the surface quality on the system performance is studied with special concern on focusing beam without structured or non-uniform pattern. Considering the characteristics of the real mirror error, the general requirement on the mirror surface quality is given for HEPS beamline design.

The advanced light source including Free Electron Laser (FEL) and Synchrotron Radiation Facility, active X-ray optics is very important for X-ray transport with high efficiency in beamlines, which has been proved by the decade’s development and application of bimorph mirrors. In this report, we report a new type of X-ray active optics - the deformable mirror based on thermal-heat effect. Simulation results shows that the mirror provides high spatial resolution over traditional bimorph mirror. In addition, the features of simple process and low cost make it possible to reduce high quality requirement on other X-ray optics.

Laser decoy is widely used in the field of electro-optical countermeasures, against laser guided semi-automatic weapons. Decoy laser usually includes a laser light source with specific wavelength and signal, whose energy distribution has Lambertian reflection characteristics. With a 633nm laser source, a fibre and a diffusive module, a homogeneous field laser was illustrated, which was generated through high-density colloidal dispersion to get diffused. By optimizing the fibre and structure parameters, the laser light energy utilization was improved while maintain light field uniformity. Additionally, the flat field system was designed and tested using high reflectivity PTFE material, with a reflectivity of 97%. A developed Lambertian light source system for reference-based Laser decoy was established, whose non-uniformity was lower than 0.3%. The results showed that the Lambertian light source system could meet the requirement of Laser decoy, and needed to be improved in near infrared.

The third generation synchrotron radiation source like High Energy Photon Source (HEPS, Beijing) requires X-ray optics surface with high accuracy. It is crucial to develop advanced optics surface metrology instrument. The Long Trace Profiler (LTP) is an instrument which measures slope in the long dimension of an optical surface. In order to meet the accuracy requirements for synchrotron optics, a number of researches have been carried out to improve the LTP during the last decades. Many variations have been installed worldwide. As a part of the advanced research of HEPS, the metrology laboratory at Beijing Synchrotron Radiation Facility (BSRF, Beijing) has been conducting work of building a new LTP since 2012. The accuracy of the instrument is expected to be

Image restoration for constructing high-spatial-resolution images in an imaging system which realizes indirectly far-filed imaging by integrating the microlenses array with LCD is reported. We have investigated the indirectly far-field imaging condition where adjacent sampling points contribute the detected signal. Experimental setup with microlens of 500 μm diameter and 8 mm focal length is built to prove this condition by studying performance of image restoration using modified point spread function (PSF). Since any one iterative method is not optimal for all image deblurring problems, some deblurring algorithms including direct deconvolution and iterative deconvolution are applied to our imaging system and we compared the effectiveness of these iterative procedures to choose right one for our use.

This paper presents an improvement approach to realize tracking on smooth glass surface based on subjective speckle. The scattering mechanism on glass surface is analyzed and the affection on tracking precise and range for tracking with subjective speckle is researched. The speckle captured by CCD just from the upper surface of the glass is achieved by grazing incidence of the laser beam and the noise mixed with the signal is eliminated by a barrier above the surface. Based on the apparatus of subjective speckle tracking, the speckle contrast is improved from 0.25 to 1.25 by non-Gauss effect and the range of the tracking has been increased from 200 μm to 400 μm compared with the objective speckle method on the same condition.

We demonstrate a laser Doppler velocimeter (LDV) based on self-mixing effect in a single longitudinal mode VCSEL for velocity measurement of flowing milk using Polymer Optical Fiber (POF). We find that self-mixing signal in frequency domain was broadened using POF compare with space coupled. The flow velocity was measured when POF outside and inside the milk. Their self-mixing signals of power spectrum can be fitted with Gaussian and exponential decay function, respectively. The differences of self-mixing signal in frequency domain when POF outside and inside milk are discussed. Due to POF have the advantages of flexibility and compatible with biology, this velocimeter can also be used for the measurement of blood flow in vivo.

This paper proposed a method by using integral imaging for computationally reconstructing three-dimensional (3D) images from different viewing points without introducing additional system complexity. In this method, the process of 3D scene sensing is accomplished by using a microlens array to obtain elemental images. The multi-viewing-points reconstruction process is carried out by computationally simulating optical reconstruction. The prototype displays differently directional views with a horizontal or vertical angle pitch of 3°~1°, when the depth range of object is from 150mm to 450mm. The viewing angle of one image point is about 53°. By optimizing the parameters of imaging system, the angle pitch would satisfy the requirement of practical application. The experimental results proving the effectiveness of the method are given.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.