1992 Fiscal Year Final Research Report Summary
Waveness Profilometer of Large Optical Parts Insensitive to the Waveness and Roughness of Reference Mirror
Project/Area Number |
02650028
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Research Category |
Grant-in-Aid for General Scientific Research (C)
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Allocation Type | Single-year Grants |
Research Field |
物理計測・光学
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Research Institution | KANAZAWA University |
Principal Investigator |
ADACHI Masaaki KANAZAWA Univ. Asst. Prof. (FACULTY OF TECHNOLOGY), 工学部, 講師 (50212519)
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Co-Investigator(Kenkyū-buntansha) |
TAKEUCHI Nozomu KANAZAWA Univ. Prof. (FACULTY OF TECHNOLOGY), 工学部, 教授 (20035588)
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Project Period (FY) |
1990 – 1992
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Keywords | Interferometer / Profilometer / Digital signal processing / Supersmooth-surface |
Research Abstract |
A profiling instrument is developed for large supersmooth surfaces, which has a height sensitivity of 0.1 nm under vibrational environments of approximately 0.4-gal root mean square. In taking a profile, a measurement point is scanned on a surface at a constant rate. An interferometric system continues to measure a differential height between the aimed point and its surroundings. The same part in a reference mirror is used during the measurement, then the roughness of the mirror does not affect the measured data. The differential height has the attenuated intensities for high spatial-frequency components. However, a digital signal processing can retrieve the original intensities of the components except one characteristic parameter, the radius of curvature of the surface. This radius can be evaluated from the data which have been measured by this instrument for another large smooth surface having a known absolute profile.
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