TWI268456B - Signal processing method for a heterodyne laser system - Google Patents

Signal processing method for a heterodyne laser system

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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
Application number
TW093140341A
Other languages
Chinese (zh)
Other versions
TW200622954A (en
Inventor
Shih-Kang Kuo
Chuan-Cheng Hung
Chang-Ching Lin
Koung-Ming Yeh
Original Assignee
Metal Ind Res & Dev Ct
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Publication date
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Priority to TW093140341A priority Critical patent/TWI268456B/en
Publication of TW200622954A publication Critical patent/TW200622954A/en
Application granted granted Critical
Publication of TWI268456B publication Critical patent/TWI268456B/en

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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.
TW093140341A 2004-12-23 2004-12-23 Signal processing method for a heterodyne laser system TWI268456B (en)

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

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Family Applications (1)

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TW093140341A TWI268456B (en) 2004-12-23 2004-12-23 Signal processing method for a heterodyne laser system

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Country Link
TW (1) TWI268456B (en)

Cited By (3)

* Cited by examiner, † Cited by third party
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

Cited By (3)

* Cited by examiner, † Cited by third party
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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