| Paper Abstract and Keywords |
| Presentation |
2007-02-16 14:40
Multilayered Surface Shape Measurement by Synthesis of Optical Coherence Function with Continuous Frequency Modulation
Hui Ouyang, Zuyuan He, Kwang-Yong Song, Masato Kishi, Kazuo Hotate (Univ. of Tokyo) |
| Abstract |
(in Japanese) |
(See Japanese page) |
| (in English) |
It is well known that a continuous surface shape can be measured by analyzing the interference between reflections from the surface and from a standard reference mirror. In the case of a multilayered object, however, this technique will be failed due to complicate interference between the reflections from the multi-layer surfaces of the object and from the reference mirror. To solve the problem, we need a method to extract selectively the interference between the reflection from an individual surface and that from the reference mirror. The technique called synthesis of optical coherence function (SOCF) provides a solution. Previously, we employed the SOCF technique with stepwise optical frequency modulation for the application. In this work, we use continuous modulation for SOCF to realize the multilayer surface measurement, which can expectedly provide higher measurement speed.
The visibility of the interference pattern in an interferometer is proportional to the coherence degree of the light source. When using a laser diode as the light source, and modulating its light frequency by directly modulating the injection current with a sinusoidal signal, in the viewpoint of time-averaging, the coherence degree is synthesized into a series of narrow peaks. The interval of the coherence peaks is adjustable by changing the modulation frequency. We use the first coherence peak as the measurement window to select the surface to be measured, and by changing the modulation frequency, we can selectively measure individual surfaces one by one. As one surface is selected, we take the fast Fourier transform (FFT) of the optical intensity of the interference fringe. After the process of filtering and inverse Fourier transform, we obtain a phase map which represents the surface shape. The unevenness is then calculated.
Theoretical analysis and experimental demonstration will be presented. |
| Keyword |
(in Japanese) |
(See Japanese page) |
| (in English) |
Fast Fourier Transform(FFT) / Synthesis of Optical Coherence Function(SOCF) / Multilayered Surface Shape Measurement / Interference Fringe / Continuous Frequency Modulation / / / |
| Reference Info. |
IEICE Tech. Rep., vol. 106, no. 532, OPE2006-167, pp. 23-28, Feb. 2007. |
| Paper # |
OPE2006-167 |
| Date of Issue |
2007-02-09 (OPE) |
| ISSN |
Print edition: ISSN 0913-5685 |
| Download PDF |
|
| Conference Information |
| Committee |
OPE |
| Conference Date |
2007-02-16 - 2007-02-16 |
| Place (in Japanese) |
(See Japanese page) |
| Place (in English) |
Kikai-Shinko-Kaikan Bldg. |
| Topics (in Japanese) |
(See Japanese page) |
| Topics (in English) |
Lightwave sensing, control, detection and measurement |
| Paper Information |
| Registration To |
OPE |
| Conference Code |
2007-02-OPE |
| Language |
English (Japanese title is available) |
| Title (in Japanese) |
(See Japanese page) |
| Sub Title (in Japanese) |
(See Japanese page) |
| Title (in English) |
Multilayered Surface Shape Measurement by Synthesis of Optical Coherence Function with Continuous Frequency Modulation |
| Sub Title (in English) |
|
| Keyword(1) |
Fast Fourier Transform(FFT) |
| Keyword(2) |
Synthesis of Optical Coherence Function(SOCF) |
| Keyword(3) |
Multilayered Surface Shape Measurement |
| Keyword(4) |
Interference Fringe |
| Keyword(5) |
Continuous Frequency Modulation |
| Keyword(6) |
|
| Keyword(7) |
|
| Keyword(8) |
|
| 1st Author's Name |
Hui Ouyang |
| 1st Author's Affiliation |
The University of Tokyo (Univ. of Tokyo) |
| 2nd Author's Name |
Zuyuan He |
| 2nd Author's Affiliation |
The University of Tokyo (Univ. of Tokyo) |
| 3rd Author's Name |
Kwang-Yong Song |
| 3rd Author's Affiliation |
The University of Tokyo (Univ. of Tokyo) |
| 4th Author's Name |
Masato Kishi |
| 4th Author's Affiliation |
The University of Tokyo (Univ. of Tokyo) |
| 5th Author's Name |
Kazuo Hotate |
| 5th Author's Affiliation |
The University of Tokyo (Univ. of Tokyo) |
| 6th Author's Name |
|
| 6th Author's Affiliation |
() |
| 7th Author's Name |
|
| 7th Author's Affiliation |
() |
| 8th Author's Name |
|
| 8th Author's Affiliation |
() |
| 9th Author's Name |
|
| 9th Author's Affiliation |
() |
| 10th Author's Name |
|
| 10th Author's Affiliation |
() |
| 11th Author's Name |
|
| 11th Author's Affiliation |
() |
| 12th Author's Name |
|
| 12th Author's Affiliation |
() |
| 13th Author's Name |
|
| 13th Author's Affiliation |
() |
| 14th Author's Name |
|
| 14th Author's Affiliation |
() |
| 15th Author's Name |
|
| 15th Author's Affiliation |
() |
| 16th Author's Name |
|
| 16th Author's Affiliation |
() |
| 17th Author's Name |
|
| 17th Author's Affiliation |
() |
| 18th Author's Name |
|
| 18th Author's Affiliation |
() |
| 19th Author's Name |
|
| 19th Author's Affiliation |
() |
| 20th Author's Name |
|
| 20th Author's Affiliation |
() |
| 21st Author's Name |
|
| 21st Author's Affiliation |
() |
| 22nd Author's Name |
|
| 22nd Author's Affiliation |
() |
| 23rd Author's Name |
|
| 23rd Author's Affiliation |
() |
| 24th Author's Name |
|
| 24th Author's Affiliation |
() |
| 25th Author's Name |
|
| 25th Author's Affiliation |
() |
| 26th Author's Name |
/ / |
| 26th Author's Affiliation |
()
() |
| 27th Author's Name |
/ / |
| 27th Author's Affiliation |
()
() |
| 28th Author's Name |
/ / |
| 28th Author's Affiliation |
()
() |
| 29th Author's Name |
/ / |
| 29th Author's Affiliation |
()
() |
| 30th Author's Name |
/ / |
| 30th Author's Affiliation |
()
() |
| 31st Author's Name |
/ / |
| 31st Author's Affiliation |
()
() |
| 32nd Author's Name |
/ / |
| 32nd Author's Affiliation |
()
() |
| 33rd Author's Name |
/ / |
| 33rd Author's Affiliation |
()
() |
| 34th Author's Name |
/ / |
| 34th Author's Affiliation |
()
() |
| 35th Author's Name |
/ / |
| 35th Author's Affiliation |
()
() |
| 36th Author's Name |
/ / |
| 36th Author's Affiliation |
()
() |
| Speaker |
Author-1 |
| Date Time |
2007-02-16 14:40:00 |
| Presentation Time |
25 minutes |
| Registration for |
OPE |
| Paper # |
OPE2006-167 |
| Volume (vol) |
vol.106 |
| Number (no) |
no.532 |
| Page |
pp.23-28 |
| #Pages |
6 |
| Date of Issue |
2007-02-09 (OPE) |