Papers by Keyword: Position Sensitive Detector (PSD)

Abstract: Aimed at the noise of PSD (position sensitive detector) system signal,In view of the PSD system signal characteristic, the wavelet way is provided for filtering and de-noising to improve system precision. Suitable wavelet processing method db10 is selected, The simulation results indicate that the algorithm can be a better way to filtering and de-noising.

Abstract: To solve the problem that bending caused by the weight of gun barrel will affect firing accuracy, the paper put forward a method that uses position sensitive detector (PSD) , gun barrel robot and some other testing equipments to carry on a automated measurement on gun barrel, and establish a correcting model according to the measured results. By this way it can amend gun launch angle to improve firing accuracy and the hitting accuracy of first Shot.

Abstract: A novel method adopting position sensitive detector (PSD) and laser collimation technique to measure four-degree-of-freedom of linear guide rails is presented in this paper. The yaw and pitch errors can be obtained based on the relationship between output coordinates of horizontal PSD and angle of the mirror. Meanwhile, the horizontal and vertical straightness errors can be calculated by the relationship between output coordinates of vertical PSD and position of sampling points. Besides, BP neural network algorithm is used to correct the nonlinearity between actual and ideal output of PSD. The method is analysed theoretically in detail. The experimental results show that the four-degree-of-freedom of linear guide rails can be measured with high accuracy.

Abstract: The dynamic precision of linear guideway is very important performance for mechatronic equipments. The dynamic errors for the linear guideway of machine tools can reduce machining precision. In according with the advantage of high-speed response, high detection accuracy and non-contact measurement, position sensitive detector (PSD) is widely used in industrial dynamic measurement. In this paper an approach for measuring the motion stability based on PSD is proposed. The measurement system based on PSD is designed and the measurement errors are analyzed. The measurement results show the approach can measure accurately the motion stability of guideway in two dimensions with features of high precision.

Abstract: In this paper, the novel measurement system for estimating the six geometric error of rotary table has been proposed. This system configuration comprising four components namely laser diode, beam splitter, position sensitive detector (PSD) and deflecting mirror. The advantage of this approach is that all six geometric error of rotary table can be evaluated by just measuring four set of points from this system configuration. To estimate the geometric errors, a linear relationship is established mathematically between measurement points and geometric errors. The line equation and plane equation along with homogeneous transformation matrix are used to define the linear relationship. The mathematical model is simulated to verify the validity of the system; the result shows the proposed system is suitable to measure the geometric errors of rotary table.

Abstract: We report on a novel method for measurement of the strain in microcantilever, and a contactless measurement system for strain in microcantilever is designed and implemented based on position sensitive detector (PSD) using optical lever method. To verify the validity and accuracy of the results from measurement, a finite element model of the uniform strength microcantilever has been developed to simulate mechanical behavior in microcantilever based on finite element method (FEM). The results show that results obtained from FEM and measurement based on PSD show excellent agreement. This work has provided a novel and more effective method for measurement of the strain in microcantilever.

Abstract: Interferometric signals of a homodyne Michelson interferometer appear in sinusoidal forms. In this investigation, new concepts for signal processing of Michelson interferometer are demonstrated. With the utilization of detection of position sensitive detector (PSD) and by the procedure of differential signals and the characteristic of symmetric waveform, a compact signal processing for homodyne Michelson interferometer has been developed. Its advantages include simplified procedure, fast processing and few electronic hardware. For experiment tests of the signal processing, a conventional homodyne Michelson interferometer has been constructed. Major components of the interferometer consist of laser light source, beam splitter, mirrors, PSD and piezo transducer for driving measurement mirror. To verify the performance of the signal processing, a commercial nanopositioning stage as reference standard has been utilized for comparison measurements. Through theoretical analysis and experiment tests, it can be proved that by the developed signal processing an interferometer possesses the optical resolution of 79 nm. With support of the developed signal processing, interferometers will possess the benefits of simply structure, few components and lower cost.

Abstract: For the measurement of ultra smooth surface topography, a surface image scanning device measurement head mechanism based on the principle of atomic force microscope (AFM) was designed. It uses coarse adjustment, semi-delicate adjustment, delicate adjustment triple-stage adjustment mechanism, and tests the atomic force between the sample and the probe by using laser generator, position sensitive detector (PSD), cantilever and probe. This mechanism has high setting accuracy and resetting accuracy, combined with two-dimension movable table, can scan the surface topography of samples.

Abstract: This work aims to report results of the spatial and frequency optical detection limits of integrated arrays of 32 one-dimensional amorphous silicon thin film position sensitive detectors with nip or MIS structure, under continuous and pulsed laser operation conditions. The arrays occupy a total active area of 45 mm2 and have a plane image resolution better than 15 m with a cut-off frequency of about 6.8 kHz. The non-linearity of the array components varies with the frequency, being about 1.6% for 200 Hz and about 4% for the cut-off frequency (6.8 kHz).

Abstract: Silicon strip detectors represent a new class of one-dimensional position-sensitive single photon counting devices. They allow a reduction of measurement time at the powder diffractometers by a factor up to 100 compared to instruments with a single counter, while maintaining comparable count statistics. Present work describes a 128-channel detector working with a standard diffractometer. The detector is 12.8 mm long and covers the angular range of 3.2 deg. We discuss the diffraction geometry in real and reciprocal space, the FWHM of diffraction peaks, and the background level. Measurements were made on standard samples and on complex samples of industrial importance (e. g., portland clinker). Applications of the detector to diffraction measurements of single crystals and thin films are discussed briefly.