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In order to overcome the shortcomings of traditional vision methods in the field of vehicle driving assistance, include visible light imaging system is vulnerable to the influence of illumination conditions and small field of view (FOV) imaging system has a large blind area, this paper proposed an environmental perception method based on ultra-wide FOV infrared imaging system. However, due to the compression of the Ultra-wide FOV infrared lens, the target occupies fewer pixels, and the detection distance is greatly limited. Therefore, this paper studies the feasibility of the application of Ultra-wide FOV infrared imaging system in the vehicle auxiliary driving system from the road objectives imaging size. Firstly, the general model of fisheye camera is used to build the imaging model of the Ultra-wide FOV infrared camera. Then, the vehicle driving safety distance and pedestrian imaging size characteristics are analyzed. Then the pedestrian detection distance of the Ultra-wide FOV infrared imaging system is simulated theoretically. Finally, a set of Ultra-wide FOV imaging system, which the FOV is 143° × 106° FOV and the detector resolution is 800 × 600, is used to carry out the experiment. The experiment shows that the pedestrian detection distance of the system proposed in this paper is more than 100 m, which can meet the needs of assistant driving at medium and low speeds.

According to the working principle of the binocular photoelectric instrument optical axis parallelism digital calibration instrument, and in view of all components of the instrument, the various factors affect the system precision is analyzed, and then precision analysis model is established. Based on the error distribution, Monte Carlo method is used to analyze the relationship between the comprehensive error and the change of the center coordinate of the circle target image. The method can further guide the error distribution, optimize control the factors which have greater influence on the comprehensive error, and improve the measurement accuracy of the optical axis parallelism digital calibration instrument.

Experimental program is designed to analyze the radiation and absorption characteristic of the sky background at near-infrared Oxygen A absorption band of passive ranging based on Oxygen spectral absorption; an acousto-optic tunable hyper spectral imaging spectrometer is used as the measuring device. Under the condition of sunny, cloudy, and snowy weather, the sky background spectral distribution is collected using the acousto-optic tunable hyper spectral imaging spectrometer. Then the Oxygen absorption rate is calculated according to the principle of Oxygen spectrum absorption passive ranging. The measurement result shows: absorption lines exist in the sky background spectral distribution at the Oxygen A absorption band, and the absorption rates are different at different weather conditions. The Oxygen absorption rates are the biggest under snowy weather, bigger under cloudy weather, and the smallest under sunny weather. The general change pattern of Oxygen absorption rate under different weather conditions is obtained and the result has laid solid foundation for suppressing the interference of the background and extracting target spectral accurately in subsequent passive ranging researching.

With the wide application of laser beams in the atmosphere, such as optical communications, the propagation of high-power laser beams and laser ranging, the propagation of laser beams in turbulent atmosphere has been studied extensively for many years. The atmospheric turbulence severely influences the beam quality and therefore the efficiency of the technology. Up to now, there have been many studies in random effects on laser beams propagation through atmosphere. Typically, M 2 factor which is a very important parameter for characterizing the laser beam quality is widely investigated. In this paper, energy Strehl ratio was utilized to characterize the laser beam quality. The propagation of a collimated Gaussian beam through atmospheric paths was numerically simulated using phase screens by the FFT method. And the effects of various factors such as atmosphere turbulent parameter C 2 n , the inner scale, the outer scale and meteorological parameters on energy Strehl ratio were analyzed by means of probability statistics. The results show that the mean of energy Strehl ratio decreases with the transmission distance increasing, and it is the same with strong refractive index fluctuation. However, the beam quality may be improved in shorter distance when energy Strehl ratio is larger than 1. The energy density of the laser beam after propagating through turbulent atmosphere in the radius of that in vacuum can be calculated by energy Strehl ratio. It may represent the accepting states of the laser beam in a short distance.

A tracking algorithm based on arbitrary geometric shape and Unscented Particle Filter is proposed in this paper. Traditional tracking algorithm based on arbitrary geometric shape has following advantages, matching convenient, high precision, but when the geometric shape is not fully visible it results tracking failure so that restricts its use. Another tracking algorithm based on natural feature utilizes natural feature points to finish registration, there are disadvantages such as error accumulation as time goes by. This approach firstly uses arbitrary geometric shape to finish camera calibration, then use unscented particle filter to predict the possible location of the camera, and get 3-D registration matrix, it can reduce non-linear, non-Gaussian interfere brought by other issues. Experiment results show that this method can efficiently work under the circumstances of occlusion, large changes in illumination, and have a high accuracy.

Image intensifier is the kernel of low-light-level device. The field flaw is one of the important index parameters of the image intensifier. Traditionally the statistic number of the image intensifier’s field flaws is calculated through the people’s eyes by the aid of an optical microscope, which main limitation is subjective and inefficient. With the broad application of the high-powered CCD and digital imaging proces sing method in testing performance of image intensifier, the method of appraising SNR based on spatio-temporal noise theory can accurately reflect the spatio-temporal heterogeneous of fluorescence’s output image and fulfill the re quirements of digital and automatic test. The limitation of the flaws’ shape and position can be disr egard and the accurate flaws’ inspection can be realized rapidly by this method. In this paper, the main factors of forming the field flaws are analyzed and the mathematic model of spatio-temporal SNR is deduced. The hardware devices of the test system for image intensifier’s spatio-temporal SNR are discussed. The spatio-temporal SNR of Gen im age intensifier is tested by this test system and the test software based on Visual C++ an d Matlab. The digital and automatic test of a factitious field flaw is realized by the theory of spatio-temporal SNR. The test precision can achieve pixel level. The experimental results show that this new method is rational, reliable and visualized. Keywords: image intensifier, field flaws, spatio-temporal SNR, test

Image intensifier is the kernel of the low-light-level image device. Output signal-to-noise ratio is one of its important parameters which can reflect the image intensifier’s imaging quality. Traditionally the test of image intensifier’s output signal-to-noise raito is realized by using a multiplier phototube, which method only gets the output signal-to-noise ratio of temporal field and can not evaluate the effect of the space structure’s nonhomogeneity of the fluorescence screen in the round. In view of these defects, the traditional method is replaced by a new one based on the three-dimensional noise theory. In this paper, a set of test formulas of output signal-to-noise ratio in spatio-temporal field which can roundly evaluate the image intensifier’s imaging quality are deduced, a test system based on the planar CCD image gathering and processing system with high sensitivity and low noise is designed. By using digital image processing technology based on Visual C++ and Matlab, a part of tested data of some home image intensifiers are given and subsequently some 3-D graphs of noise which can describe the spatical-temporal field’s imaging character in different brightness gain are drawn. The practical results can show that the new test method is rounded, accurate and visualized.

A new method to deal with images by computer is put forward, which is more convenient for the eyes to identify and much easier to understand. As the image edge is a basic character of image, checking it is one of the most important parts in processing the image. The traditional technique is to use the edge detection algorithm, which is to detect the gray level changes of every pixel of image in some epsilon, and to detect the image edge by using the changing regular of directional derivative. But sometimes there is uncertainty of image edge, and man can't distinguish it is the edge or not. Diagram algorithm can't solute this pivotal problem. In order to turn the fuzzy edge to be in focus and solve the problem above, this paper mentions fuzzy enhancing technique to realize image edge's being detected. Fuzzy technology is a newly rising technology used in many fields, especially in the image domain, and fuzzy enhancing technique is one important portion of the fuzzy technology. Based on this technology, this paper firstly sets the image fuzzy characteristic plane of original image, secondly proceeds the fuzzy enhancement, and then detects the edge by Sobel differential arithmetic. At the end of the paper, it realizes the histogram algorithms and the fuzzy enhancing algorithm by Visual C++. Results of the experiment show that fuzzy enhancing algorithm is a superior one in image procession.

Automation and intelligent function in performance testing of optical instrument are the key problems in modern detection technology. In this paper a testing system based on the detection in laboratory is proposed and has successfully realized the detection of multi-optical axes’ parallelism. This system is on the base of optics, mechanics and electricity, and combines the modern computer technology to gather and process the data obtained in the experiment, finally high-precision quantified results can be gotten, so these results can provide reliable data for the alignment of optical axes. The paper introduces the whole testing system’s design options, system composition, operational principle and software design in detail, and it’s technical difficulties and emphases are also analyzed and discussed.

A new type of design for the thermal imaging radiometer is presented in this paper. The new system has many advantages, such as that the apparent temperature configuration of the measured object is showed with image manner, that measure results and parameters of system status is displayed with graphics intuitively, that measure data can be saved easily and conducted further process, etc. Besides these, it has very nicer imaging radiation measure capability, high automatization degree. Its orientation is easy, and field experimental operation is convenient. With so many advantages, it offers an effective method to realize the spatial distributed measure for a target’s infrared radiation, the measure for its variation per hour and the measure for its intensity and dynamic range of the radiation.

The principle of determining passive incident laser beam's space direction by use of linear array CCD deice and structural design of the system are analyzed theory and experiment show passive incident laser beam's space direction can be determined accurately and quickly.