| A novel interferometric measurement system, which is based on optical line-scanning and suitable for the measurement of3-D nano-surface profile, is proposed. The broadband light emitted from an amplified spontaneous emission (ASE) is dispersed into a piece of fan-shaped light by a blazed grating. The piece of fan-shaped light is collimated into a piece of parallel light and then is used to scan the measured surface. Different wavelength is reflected by the different measured point of the surface. The reflected wavelength is interfered with the reference light. Each pixel of a line array CCD detects the interferometric signal from the corresponding measured point of the surface. The height of the measured point of the surface will be obtained. The optical line-scanning interferomteric measurement will be realized by demodulating every interferometric signal from each pixel of the CCD. In the experiment, a smooth surface of a mirror is used as the measured surface to demonstrate the feasibility of the system. And the result we get is a straight line after the data is processed, which shows that the experiment result agrees well with the theoretical analysis. Some problems have been found in the system if it is used to the practical measurement that have founded the basic work for the further research.. Compared to the optical point-scanning3-D nano-surface profile measurement system, the presented system has the advantages of fast measurement speed and simple scanning structure. |
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