Browsing by Author "Chiu, MH"

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A heterodyne interferometer using an electro-optic modulator for measuring small displacements
(1996-01-01)
Su, DC
;
Chiu, MH
;
Chen, CD
;
交大名義發表
;
光電工程學系
In this heterodyne interferometer for measuring small displacements, an electro-optic modulator is used as a frequency shifter. It has some merits, such as, free from the mechanical vibration, simple and compact optical structure, and a general and inexpensive electrical signal processing circuit can be used without decreasing the measuring resolution and easily operated in real time.
Angle measurement using total-internal-reflection heterodyne interferometry
(1997-06-01)
Chiu, MH
;
Su, DC
;
交大名義發表
;
光電工程學系
;
National Chiao Tung University
A new optical method for angle measurement based on total-internal-reflection heterodyne interferometry is presented. In this method, heterodyne interferometry is applied to measure the phase difference between s and p polarization states at total internal reflection. This phase difference depends on the angle of incidence. Hence, small-angle measurement can be performed only by evaluating this phase difference. The validity of the method is demonstrated, and it has a measurement range of 10 deg. Its resolution depends on the angle of incidence; the best resolution is 8x10(-5) deg. (C) 1997 Society of Photo-Optical Instrumentation Engineers.
Angle measurement using total-internal-reflection heterodyne interferometry
(1997-06-01)
Chiu, MH
;
Su, DC
;
光電工程研究所
;
Institute of EO Enginerring
A new optical method for angle measurement based on total-internal-reflection heterodyne interferometry is presented. In this method, heterodyne interferometry is applied to measure the phase difference between s and p polarization states at total internal reflection. This phase difference depends on the angle of incidence. Hence, small-angle measurement can be performed only by evaluating this phase difference. The validity of the method is demonstrated, and it has a measurement range of 10 deg. Its resolution depends on the angle of incidence; the best resolution is 8x10(-5) deg. (C) 1997 Society of Photo-Optical Instrumentation Engineers.
Central fringe identification using a heterodyne interferometric technique and a tunable laser-diode
(1996-07-15)
Lee, JY
;
Chiu, MH
;
Su, DC
;
光電工程研究所
;
Institute of EO Enginerring
A novel method combining a heterodyne technique and a tunable laser diode for identifying the central fringe of an interferogram is presented. It has some merits, such as simple optical structure, easier operation, etc. Its feasibility is demonstrated.
Central fringe identification using a heterodyne interferometric technique and a tunable laser-diode
(1996-07-15)
Lee, JY
;
Chiu, MH
;
Su, DC
;
交大名義發表
;
光電工程學系
A novel method combining a heterodyne technique and a tunable laser diode for identifying the central fringe of an interferogram is presented. It has some merits, such as simple optical structure, easier operation, etc. Its feasibility is demonstrated.
Complex refractive index measurements based on Fresnel's equations and the uses of a lock-in amplifier
(1999)
Su, DC
;
Chiu, MH
;
Lee, JY
;
光電工程學系
;
Department of Photonics
A new method for measuring complex refractive index is presented based on Fresnel's equations and the uses of a lock-in amplifier. A lock-in amplifier is introduced into a common path interferometer to measure the product of the amplitude reflection coefficients of s and p polarizations and their corresponding phase difference of a light beam reflected from a medium with complex refractive index. Then, these data are substituted into the special equations derived from Fresnel's equations, the complex refractive index can be obtained by numerical calculations. The resolution of this method is better than 0.01. It has both merits of a conventional common-path interferometer and a heterodyne interferometer. And its validity is demonstrated.
Complex refractive-index measurement based on Fresnel's equations and the uses of heterodyne interferometry
(1999-07-01)
Chiu, MH
;
Lee, JY
;
Su, DC
;
光電工程學系
;
Department of Photonics
The phase difference between s and p polarization of the light reflected from a material is used for measuring the material's complex refractive index. First, two phase differences that correspond to two different incidence angles are measured by heterodyne interferometry. Then these two phase differences are substituted into Fresnel's equations, and a set of simultaneous equations is obtained. Finally, the equations are solved by use of a personal computer by a numerical analysis technique, and the complex refractive index of the material can be estimated. (C) 1999 Optical Society of America.
Improved technique for measuring small angles
(1997-10-01)
Chiu, MH
;
Su, DC
;
交大名義發表
;
光電工程學系
;
National Chiao Tung University
Based on the total-internal-reflection effect and heterodyne interferometry, an improved technique for measuring small angles is proposed. This technique not only expands the measurement range but it also improves measurement performances. Its validity is demonstrated. (C) 1997 Optical Society of America.
Improved technique for measuring small angles
(1997-10-01)
Chiu, MH
;
Su, DC
;
光電工程研究所
;
Institute of EO Enginerring
Based on the total-internal-reflection effect and heterodyne interferometry, an improved technique for measuring small angles is proposed. This technique not only expands the measurement range but it also improves measurement performances. Its validity is demonstrated. (C) 1997 Optical Society of America.
Measurements of material refractive indices using heterodyne interferometry
(2000)
Su, DC
;
Lee, JY
;
Hsu, CC
;
Chiu, MH
;
光電工程學系
The phase difference between s- and p- polarizations of the reflected light from a test material is measured using heterodyne interferometry. The measured data is substituted into the specially derived equations and the refractive index can be calculated. When an absorbing material is tested, a general heterodyne light source is used and two measurement processes should be performed because of its two unknown parameters to be solved. And only one measurement process is performed with a circularly polarized heterodyne light source for testing a non-absorbing material. Because the phase difference can be measured accurately with heterodyne interferometry, its performance is not affected by surrounding light noise. So, it is very stable and has a high resolution.
Method for determining the fast axis and phase retardation of a wave plate
(1996-09-01)
Chiu, MH
;
Chen, CD
;
Su, DC
;
光電工程研究所
;
Institute of EO Enginerring
Based on the heterodyne interferometric technique and the discrimination technique of using two light beams with different wavelengths, a novel method for identifying the fast axis of a wave plate and evaluating its phase retardation is presented. Some of the merits of the method, such as, a simple optical setup, high stability, better resolution, and easier operation, are presented, and the validity of the method is demonstrated. (C) 1996 Optical Society of America.
Method for determining the fast axis and phase retardation of a wave plate
(1996-09-01)
Chiu, MH
;
Chen, CD
;
Su, DC
;
交大名義發表
;
光電工程學系
Based on the heterodyne interferometric technique and the discrimination technique of using two light beams with different wavelengths, a novel method for identifying the fast axis of a wave plate and evaluating its phase retardation is presented. Some of the merits of the method, such as, a simple optical setup, high stability, better resolution, and easier operation, are presented, and the validity of the method is demonstrated. (C) 1996 Optical Society of America.
New type of liquid refractometer
(1998-10-01)
Su, DC
;
Lee, JY
;
Chiu, MH
;
光電工程研究所
;
Institute of EO Enginerring
In a new type of liquid refractometer, the phase difference variation between s and p polarizations produced by the total internal reflection is measured using a heterodyne interferometer with a specially designed probe. Substituting the phase difference variation into the Fresnel's equation, the refractive index can be calculated and displayed. The prototype is set up to demonstrate its feasibility. (C) 1998 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(98)02510-0].
New type of liquid refractometer
(1998-10-01)
Su, DC
;
Lee, JY
;
Chiu, MH
;
光電工程學系
;
Department of Photonics
In a new type of liquid refractometer, the phase difference variation between s and p polarizations produced by the total internal reflection is measured using a heterodyne interferometer with a specially designed probe. Substituting the phase difference variation into the Fresnel's equation, the refractive index can be calculated and displayed. The prototype is set up to demonstrate its feasibility. (C) 1998 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(98)02510-0].
Refractive-index measurement based on the effects of total internal reflection and the uses of heterodyne interferometry
(1997-05-01)
Chiu, MH
;
Lee, JY
;
Su, DC
;
光電工程研究所
;
Institute of EO Enginerring
A new method for measuring the refractive index is presented, First, the phase difference between s and p polarizations that is due to the total internal reflection is measured by heterodyne interferometry. Then, substituting this phase difference into the Fresnel equations, we can obtain the refractive index of the test medium. (C) 1997 Optical Society of America.
Refractive-index measurement based on the effects of total internal reflection and the uses of heterodyne interferometry
(1997-05-01)
Chiu, MH
;
Lee, JY
;
Su, DC
;
交大名義發表
;
光電工程學系
A new method for measuring the refractive index is presented, First, the phase difference between s and p polarizations that is due to the total internal reflection is measured by heterodyne interferometry. Then, substituting this phase difference into the Fresnel equations, we can obtain the refractive index of the test medium. (C) 1997 Optical Society of America.
Simple two-frequency laser
(1996-04-01)
Su, DC
;
Chiu, MH
;
Chen, CD
;
交大名義發表
;
光電工程學系
The optics of a simple two-frequency laser is presented. If consists of a laser, a half-wave plate, and an electro-optic modulator. Because of a simple on-axis optical setup, it has high stability easier operation, and high efficiency, without reducing the available coherence length of a laser and is suitable for two-frequency interferometry.
Vacuum measurement using total-internal-reflection heterodyne interferometry
(1999-10-01)
Chiu, MH
;
Lee, JY
;
Su, DC
;
Lee, KH
;
光電工程學系
Based on the effect that the phase difference between s- and p-polarizations at the total-internal-reflection is changed with the variation of the air refractive index, which is related to the air pressure, a new optical method for measuring the air pressure of a vacuum cavity is proposed. From the experimental curve of the phase difference variation measured by the heterodyne interferometry and the calibrated pressure measurement of a vacuum cavity, an empirical formula is derived. With this empirical formula, the mensurable range of this new optical method is 760 to 0.1 torr. (C) 1999 Elsevier Science Inc. All rights reserved.