| (Charge Coupled Devices) is a semiconductor photoelectric device with particular performance, which is applied widely in some fields such as camera and industry measurement and so on recently. The measurement system with CCD has an advantage on the geometrical such as displacement for achieving high accuracy, on-line dynamic detection, and non-contact measurement.There are several well-known advantages of optical triangle method with computer vision system in displacement measurement, for example, fast measurement speed, high measurement accuracy and far distance measurement. Furthermore, experimental image which has been collected can be analyzed, and this method is very skillful. For these reasons, triangle method is widely used in displacement measurement, thickness measurement, distance measurement and other fields.Base on laser and CCD image system, the inspected technique of puny deflectable angle measurement to object and displacement is discussed in this paper mostly. Using the optical triangle measurement method, the displacement of laser speckle is analyzed. Through be constructed the theoretical relationship between the laser displacement and reality sizing, it's easily to obtain the real displacement and roll angle. To improve the measurement accuracy, digital correlation method is used in laser speckle pattern. The result shows this method has high measurement precision and settles a foundation for latter work in measurement. In this paper, systematic error is comprehensively extracted, furthermore, the particular technique which can assure the measurement precision is proposed. In the end, contrasting to measurement value and theoretical value of the deflection and roll angle for the equivalent intensity cantilever beam, it's proved that this measurement system works at a high accuracy. This measurement system and analysis technique is benefit to inspect not only the deformation of tiny specimen but also large engineering structure such as bridge distortion. |
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