| With the rapid development of such technologies as miniaturized machining, micro-optical, micro-mechanics and micro-electronics, how to measure the 3-D surface topography of micro-specimens quickly and accurately has become a challenge in the field of modern micro-measurement. Confocal technology is widely applied in 3-D profile detecting field because of its unique advantages of high resolution, high accuracy, and facileness to realize the digitization of 3-D imaging. Recently, a. non-scanning whole-field confocal detecting technique attracts worldwide attentions. The method uses micro-optic components to realize the division of light beam. Multiple-beam parallel detecting is applied instead of single-point to collimate and scan. The research is based on the project sponsored by the National Natural Science Foundation of China (NSFC) and another project sponsored by Important Research Foundation of National Education Ministry of China. In this dissertation, the non-scanning whole-field confocal system and its key technologies are in-depth investigated. The optical characteristics and the accuracy of system are analyzed and validated by practical experiments. The study proposed a novel confocal measuring technique, which demonstrates good characteristics of high accuracy and high speed and thus improves the flexibility and applicability of 3D non-contact probe. It also provides a powerful theoretical foundation for the prospective application of non-contact confocal 3D detecting technology.The main work of this dissertation is as follows:(1) The work principle of parallel confocal microscopy is introduced on the basis of Fourier transform optics. The characteristic parameters of parallel confocal system are analyzed in detail. The criterions and measuring range of axial and transversal resolution are given. Moreover, the methods of design and configuration of the system are given. The factors that influence the performance of the multi-beam parallel confocal system are discussed.(2) The parallel confocal experiment system is developed based on theoretic analysis and experimental studies. System software is also designed based on VC++ 6.0. It has several function blocks based on windows interface such as image collection, axial stepped control and 3-D profile reconstruction.(3) The key techniques and approaches for system performance optimization are discussed in order to improve measurement accuracy and efficiency. The proposed methods for optical systems construction and 3-D profile reconstruction solve the problem of the deficiency of general confocal testing systems and decrease the influence of noise and other error factors.(4) The application of the digital light source in the parallel confocal microscopy is investigated, which makes the parallel confocal testing system more flexible and adaptable for the requirements of customized measurement tasks.The originalities of this dissertation are as follows:(1) Based on astigmatic method, a new 3-D profile parallel detecting method is proposed. This method uses a micro-lens array and astigmatic lens to form parallel micro-astigmatism light path. The whole-field detecting of measured plane is realized simultaneously. By using the linearity characteristic of astigmatic system, high axial resolution is achieved at a larger sampling interval, thus solve the conflict between the measuring efficiency and the measuring accuracy. The performance parameters and factors that influence the astigmatic system are discussed. Furthermore, experiment result shows good agreement with the theoretical analysis. It indicates that astigmatic method is feasible in the application of 3-D profile parallel detecting. The research has obtained a patent of utility model.(2) Based on differential confocal microscopy method, a non-scanning 3-D profile detecting system is presented. In the system the reflected light beam is divided into two differential paths, and two CCD cameras was used to detect the defocusing facula array synchronously. Because the differ...
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