Key Engineering Materials Vol. 552

Abstract: The simulator provides a virtual emulational condition. It can test the functions of infrared missile by simulating the movement of the target and the interferes. A target simulator with multiple interferences is provided in this paper. The blackbody is used as radiating source. The simulator’s construction, principle and the realization of motion track are mentioned. It has been proved that the simulator can meet the demands of development of missile. And the simulator is universal because the interference source has three bands.

Abstract: The paper aims to measure the exact position while detecting inner surface defects of large scale pipeline. A realizable method using opto-electrical is presented in this paper, which can give the position of opto-electrical sensor. On-line measured data is automatically recorded and processed with precision because of the application of step motor and gear drive, as well as software controlling computer.

Abstract: This paper studies the measurement of illumination parameters from a bright product. We are making use of diffuse reflection characteristics of the integrating sphere, which can greatly reduce the measurement error caused by the shape of the light, the divergence angle, and different location on the detector. In this way we can measure the intensity of the light source accurately, and the measurement accuracy less than 5%.

Abstract: A precise detection technique with array camera is discussed for the detection of dynamic focus position in this paper. This technique is well applicable for measuring the focal spot shifting of large and slow lens or optical systems. Two coated wedges are adopted in light path to supply bands of beams, which form the spots matrix on the detector. Focus position shifting can be indirectly obtained from position shifting of the smallest spot on the detector. The technology discussed here is simple and accurate; it also solves the problem that dynamical focal spot position shifting is immeasurable for conventional focal length measureing methods.

Abstract: Multi-element ultrasonic probe applied in vivo, compared with the traditional probe applied in vitro or single-element probe, has its own specialty in working environment and structure. This paper designed an analog circuit applied in vivo including excitation and reception amplification for multi-element ultrasonic probe. The circuit provides an excitation and receiving front-end for the self-developed multi-element ultrasound endoscope imaging system. This ultrasound analog circuit can be used for d / 2 ultrasonic scanning along with the 16 element ultrasound transducer.

Abstract: The programmable coded aperture has been applied to the optical systems to enhance their functionality and performance. Therefore, the optical system is programmable. It means that the optical system could be changed momentarily. Conventionally, during MTF measurement, the optical system is fixed. The system under test and the test equipment have no relation of time- sequence. The image sensor sample of test equipment can be random. But In the programmable optical system, the aperture style and its duration in a frame period have a impact on the system MTF. Conventional MTF measurement methods can’t be used to test accurately the MTF of programmable optical system. In this paper, we propose a method and design a system which can test precisely MTF of the programmable optical system. In this method the sample of a sensor would be synchronized with the coded aperture program logic, which ensures the precision of MTF measurement.

Abstract: Small field ArF projection optics for experiment is favorable to the prospective study and key technique development for lithography equipment. An ArF projection optics has been designed with specifications of 0.75 numerical aperture (NA), 100μm image field of view and 40X reduction ratio. The designed composite root-mean-square (RMS) of wave front error of the system can reach 0.03λ (λ=193.29nm). To achieve diffraction limited resolution, the optical manufacture tolerances of this high-NA projection optics are too tight to manufacture, such as radius error within ±0.01%, central thickness within ±2μm and surface figure error less than peak-valley (P-V) of 1/30λ (λ=632.8nm). In this paper, two effective compensatory methods are presented to relax the manufacture tolerances before assembly. One method is re-computation of air spaces including actual measured values of the radii of curvature and center thickness for each element. The second method is rotating lenses to find the best matching manner of measured surface figure. The results show that radius error, central thickness error and surface figure error can be compensated significantly，and the best performance of the projection optics disregarding assembly error has been acquired. The composite wave front error RMS can reach 0.09λ (λ=193.29 nm) after compensation, which is much smaller than 0.25λ before compensation under the same optical manufacture error. Both methods can also be used in development of industrial lithographic projection optics.

Abstract: It is difficult to measure deformation for artillery components accurately without disassembly since these components have complex structures and large dimensions. A new deformation measurement method for artillery components is introduced in this paper based on laser radar. Test data proves that laser radar’s measurement accuracy can satisfy the requirement of artillery’s approval test.

Abstract: As the increasingly improvement of modern weapons and detection technique, it is proposed that a higher demand on firing accuracy of artillery and bullet spread, and the parallelism of artillery’s directional beam was one of the important factors. The article conducted a research on the measuring methods of the parallelism of artillery’s directional beam. After concluding its shortcomings, a method of parallelism of artillery’s directional beam based on the laser radar was put forward by laser radar to detect the parallelism of artillery’s directional beam. The experimental results shown that the method can reach the detection accuracy of 0.2 mils, realize the high accuracy and high efficiency measurement.

Abstract: The distorted (scale and rotation etc.) target images and the training images are edge extracted by Prewitt operator. The Maximum Average Correlation Height filter is synthesized with the training images. The low frequency information of the distorted target images and the filter is enhanced. Then the edge extracted distorted target image is filtered by the Maximum Average correlation Height filter. Thereby, the distortion tolerance of the Maximum Average Correlation Height filter is expanded. By this method, when the space edge extraction combines with frequency domain filtering, the scale distortion tolerance is 0.76~1.56 times; the rotation distortion tolerance can reach up to 80 degrees. For the targets exceeding the distortion tolerance range, the intensity of correlation peak becomes weaker and weaker, but some of the targets can still be identified.