Optical-fiber type laser wavemeter
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 南京海莱特激光科技有限公司
- Publication Date
- 2011-08-17
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Abstract
Description
technical field
[0001] The invention relates to a wavelength meter, in particular to a fiber optic laser wavelength meter. Background technique
[0002] Excimer lasers are widely used in VLSI lithography due to their short wavelength and weak coherence. As a light source for lithography, laser output is required to have narrow linewidth and high wavelength stability. Factors such as vibration and temperature changes of the laser line width narrowing device can cause the center wavelength of the laser to drift. In order to obtain the center wavelength of the laser and judge the amount of drift between it and the target wavelength, and provide a basis for tuning the center wavelength of the laser, it is necessary to Real-time fast measurement of central wavelength and linewidth.
[0003] A common method for measuring laser wavelength is to use a Fesault interferometer, see the prior art [Chinese Patent Publication No. 1077530]. This technique requires an additional laser wi...