TWI268456B - Signal processing method for a heterodyne laser system - Google Patents
Signal processing method for a heterodyne laser systemInfo
- Publication number
- TWI268456B TWI268456B TW093140341A TW93140341A TWI268456B TW I268456 B TWI268456 B TW I268456B TW 093140341 A TW093140341 A TW 093140341A TW 93140341 A TW93140341 A TW 93140341A TW I268456 B TWI268456 B TW I268456B
- Authority
- TW
- Taiwan
- Prior art keywords
- vibration
- frequency
- vibration amplitude
- heterodyne
- signal processing
- Prior art date
Links
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- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
Abstract
This patent presents a method for measuring high frequency vibration based on a heterodyne laser interferometry system. In a heterodyne system, an electro-optic modulator is used to split the laser light into a two frequency light source with orthogonal polarization state. Usually the frequency is at least ten times higher than the vibration to be measured. However, as the high frequency measurement is desired, the conventional locking amplifier and phase lock loop cannot be applied. Therefore, a method for computing vibration amplitude based on frequency domain analysis is presented in this patent. The acquired signal is stored and is processed by fast Fourier transform to obtain the spectrum of the signal. It was found that the peak values on the spectrum provides the information of vibration amplitude and is utilized for obtaining vibration amplitude.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
TW093140341A TWI268456B (en) | 2004-12-23 | 2004-12-23 | Signal processing method for a heterodyne laser system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
TW093140341A TWI268456B (en) | 2004-12-23 | 2004-12-23 | Signal processing method for a heterodyne laser system |
Publications (2)
Publication Number | Publication Date |
---|---|
TW200622954A TW200622954A (en) | 2006-07-01 |
TWI268456B true TWI268456B (en) | 2006-12-11 |
Family
ID=57808553
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
TW093140341A TWI268456B (en) | 2004-12-23 | 2004-12-23 | Signal processing method for a heterodyne laser system |
Country Status (1)
Country | Link |
---|---|
TW (1) | TWI268456B (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
TWI403988B (en) * | 2009-12-28 | 2013-08-01 | Mstar Semiconductor Inc | Signal processing apparatus and method thereof |
US10792767B2 (en) | 2017-11-15 | 2020-10-06 | Metal Industries Research & Development Centre | Laser preheating control method and device |
CN109834468B (en) * | 2017-11-29 | 2020-12-08 | 财团法人金属工业研究发展中心 | Laser preheating control method and laser preheating control device |
-
2004
- 2004-12-23 TW TW093140341A patent/TWI268456B/en active
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
TWI403988B (en) * | 2009-12-28 | 2013-08-01 | Mstar Semiconductor Inc | Signal processing apparatus and method thereof |
US10792767B2 (en) | 2017-11-15 | 2020-10-06 | Metal Industries Research & Development Centre | Laser preheating control method and device |
CN109834468B (en) * | 2017-11-29 | 2020-12-08 | 财团法人金属工业研究发展中心 | Laser preheating control method and laser preheating control device |
Also Published As
Publication number | Publication date |
---|---|
TW200622954A (en) | 2006-07-01 |
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