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Measurement of temperature change with a heterodyne optical fibre interferometer
Abstmets Measurement of photothermal vibrational by an interference microscope
displacements
Photoacoustic placement
detection
of Nd:YAG
laser beam
Toshinori Nakajima. Hitoshi Kawai. Ichirou Yamaguchi
Minoru Sakai. Keigo Nagasaka and Hide0 Tashiro
Laser Science Progress Report of the IPCR Physical and Chemical Research)
Laser Science Progress Physical and Chemical
(Institute of
A microscope with an interference
objective has been applied to the measurement of photothermal vibrational displacements of a sample surface. A chopped beam of AR+ laser light is guided by a multimode optical fibre to excite photothermal displacements of the sample under the microscope. A HeNe laser beam for interferometric measurement is guided to the interference objective by a single-mode optical fibre. The measuring system is proved to be stable to external mechanical disturbance and photothermal vibrational displacements of the order of a nanometre can be measured.
Report of the Research)
IPCR
(Institute
of
The photoacoustic method of detecting laser beam placement was applied to the beam from a Nd:YAG laser. Difficulties arising from low signal levels due to the low absorption of the dielectric coating of the mirror were overcome with the use of an additional plate behind the mirror which received the slightly transmitted beam through the coated layer.
Optical
sensing related to multiple points and images
lchirou Yamaguchi Measurement error sensor
of small amplitude
vibrations
by a focus
Toshinori Nakajima. Eiichi Sate. Ichirou Yamaguchi Laser Science Progress Report of the Physical and Chemical Research)
IPCR
(Institute
of
A focus error sensor with a built-in interferometer has been constructed and applied to the measurement of small amplitude vibrations. The focus error sensor detects the displacement of a sample surface from the focal plane of a microscope objective as the intensity change of the reflected light. Although it is mechanically stable and its output signal is linear with the displacement over a wide range. it cannot measure the displacement quantitatively. An output signal from the interferometer is used for calibration. and vibration amplitudes down to several picometres have been detected.
Non-linear optical processes second-harmonic generation
on surfaces: on silicon surfaces
Takanori Suzuki. Takahiro Kasuya Laser Science Progress Physical and Chemical
Report of the Research)
IPCR
(Institute of
As a preliminary study on the application of the non-linear optical processes of second-harmonic (SH) and sum frequency generation to surfaces and interfaces. the second harmonic generation on a clean Si surface has been investigated. Polarization dependence of the SH intensitv is in good agreement with the well-known symmetry properties of the reconstructed silicon surface.
The Optical Engineering Laboratory, The Institute of Physical and Chemical Research. Wako. Saitama. Japan 8th Meeting on Lightwave Sensing Technology, Society of Lightwave Sensing Technology, Japan Applied Physics
Japanese Society of
Lightwave sensing techniques which deliver information at multiple points or over areas are discussed. Application fields and problems are reviewed for interferometry. tomography. spectroscopy. and uses of optical coupling with other waves.
Recent progress in optical fibre measurement
techniques
Yahei Koyamada Nm
Telecommunication
Field Systems
R&D Center
8th Meeting on Lightwave Sensing Technology. Society of Lightwave Sensing Technology. Japan Applied Physics
Japanese Society of
The efficiency of the field work for outside fibre plant construction and maintenance depends on the level of measurement techniques. Current standard measurement techniques are largely adequate for inter-office fibre links which. up to this time. have been the main application for tibres. However. considering the forthcoming largescale introduction of fibres to the subscriber loop. it is necessary to develop measurement techniques which enable field work to be performed more efficiently. This paper reviews recent topics on the subject of optical fibre measurement techniques for outside tibre plant construction and maintenance.
Polarization properties of the multiple reflection Faraday effect sensor with an LED light source
type
Ki_yoshiKurosawa. Tadashi Goto Tokyo Measurement heterodyne
of temperature change optical fibre interferometer
with a
Report of the Research)
IPCR
(Institute
of
A heterodyne optical fibre interferometer using a laser diode as the light source was applied to the measurement of temperature change of water in a glass cell. The injection current of the laser was modulated in a sawtooth waveform for heterodyne interferometry. The phase of an interference signal was shifted by the change of optical path length induced by temperature change and its shift was directly detected by means of a lock-in amplifier. Temperature sensitivity and resolution. which were dependent on the temperature ofthe water. were 5 X IO’ deg-‘C and 5 X lW4”C at 30°C respectively.
158
Power Company
8th Meeting on Lightwave Sensing Technology. Society of Lightwave Sensing Technology, Japan Applied Physics
Tohru Kawaguchi. Toshinori Nakajima. Ichirou Yamaguchi Laser Science Progress Physical and Chemical
Electric
Japanese Society of
Sensitivity enhancement of the Faraday effect current sensor can be made by using the multiple reflection type sensor element made of a flint glass plate. both sides of which are coated with dielectric multilayer reflecting mirrors. In this paper. polarization properties of the element with an LED light source of wide spectral width are studied. for the application of the element to the optical current transformer. The influence of the polarization properties to the output of the current measuring system has also been investigated. From the result of the study. it became known that the measurement error of the measuring sytem caused by the influence is very small. It also became known that adjusting the azimuth of the analyser to 0” is effective for minimizing this error.
Optics & Laser Technology Vol24
No 3 1992
displacements
Photoacoustic placement
detection
of Nd:YAG
laser beam
Toshinori Nakajima. Hitoshi Kawai. Ichirou Yamaguchi
Minoru Sakai. Keigo Nagasaka and Hide0 Tashiro
Laser Science Progress Report of the IPCR Physical and Chemical Research)
Laser Science Progress Physical and Chemical
(Institute of
A microscope with an interference
objective has been applied to the measurement of photothermal vibrational displacements of a sample surface. A chopped beam of AR+ laser light is guided by a multimode optical fibre to excite photothermal displacements of the sample under the microscope. A HeNe laser beam for interferometric measurement is guided to the interference objective by a single-mode optical fibre. The measuring system is proved to be stable to external mechanical disturbance and photothermal vibrational displacements of the order of a nanometre can be measured.
Report of the Research)
IPCR
(Institute
of
The photoacoustic method of detecting laser beam placement was applied to the beam from a Nd:YAG laser. Difficulties arising from low signal levels due to the low absorption of the dielectric coating of the mirror were overcome with the use of an additional plate behind the mirror which received the slightly transmitted beam through the coated layer.
Optical
sensing related to multiple points and images
lchirou Yamaguchi Measurement error sensor
of small amplitude
vibrations
by a focus
Toshinori Nakajima. Eiichi Sate. Ichirou Yamaguchi Laser Science Progress Report of the Physical and Chemical Research)
IPCR
(Institute
of
A focus error sensor with a built-in interferometer has been constructed and applied to the measurement of small amplitude vibrations. The focus error sensor detects the displacement of a sample surface from the focal plane of a microscope objective as the intensity change of the reflected light. Although it is mechanically stable and its output signal is linear with the displacement over a wide range. it cannot measure the displacement quantitatively. An output signal from the interferometer is used for calibration. and vibration amplitudes down to several picometres have been detected.
Non-linear optical processes second-harmonic generation
on surfaces: on silicon surfaces
Takanori Suzuki. Takahiro Kasuya Laser Science Progress Physical and Chemical
Report of the Research)
IPCR
(Institute of
As a preliminary study on the application of the non-linear optical processes of second-harmonic (SH) and sum frequency generation to surfaces and interfaces. the second harmonic generation on a clean Si surface has been investigated. Polarization dependence of the SH intensitv is in good agreement with the well-known symmetry properties of the reconstructed silicon surface.
The Optical Engineering Laboratory, The Institute of Physical and Chemical Research. Wako. Saitama. Japan 8th Meeting on Lightwave Sensing Technology, Society of Lightwave Sensing Technology, Japan Applied Physics
Japanese Society of
Lightwave sensing techniques which deliver information at multiple points or over areas are discussed. Application fields and problems are reviewed for interferometry. tomography. spectroscopy. and uses of optical coupling with other waves.
Recent progress in optical fibre measurement
techniques
Yahei Koyamada Nm
Telecommunication
Field Systems
R&D Center
8th Meeting on Lightwave Sensing Technology. Society of Lightwave Sensing Technology. Japan Applied Physics
Japanese Society of
The efficiency of the field work for outside fibre plant construction and maintenance depends on the level of measurement techniques. Current standard measurement techniques are largely adequate for inter-office fibre links which. up to this time. have been the main application for tibres. However. considering the forthcoming largescale introduction of fibres to the subscriber loop. it is necessary to develop measurement techniques which enable field work to be performed more efficiently. This paper reviews recent topics on the subject of optical fibre measurement techniques for outside tibre plant construction and maintenance.
Polarization properties of the multiple reflection Faraday effect sensor with an LED light source
type
Ki_yoshiKurosawa. Tadashi Goto Tokyo Measurement heterodyne
of temperature change optical fibre interferometer
with a
Report of the Research)
IPCR
(Institute
of
A heterodyne optical fibre interferometer using a laser diode as the light source was applied to the measurement of temperature change of water in a glass cell. The injection current of the laser was modulated in a sawtooth waveform for heterodyne interferometry. The phase of an interference signal was shifted by the change of optical path length induced by temperature change and its shift was directly detected by means of a lock-in amplifier. Temperature sensitivity and resolution. which were dependent on the temperature ofthe water. were 5 X IO’ deg-‘C and 5 X lW4”C at 30°C respectively.
158
Power Company
8th Meeting on Lightwave Sensing Technology. Society of Lightwave Sensing Technology, Japan Applied Physics
Tohru Kawaguchi. Toshinori Nakajima. Ichirou Yamaguchi Laser Science Progress Physical and Chemical
Electric
Japanese Society of
Sensitivity enhancement of the Faraday effect current sensor can be made by using the multiple reflection type sensor element made of a flint glass plate. both sides of which are coated with dielectric multilayer reflecting mirrors. In this paper. polarization properties of the element with an LED light source of wide spectral width are studied. for the application of the element to the optical current transformer. The influence of the polarization properties to the output of the current measuring system has also been investigated. From the result of the study. it became known that the measurement error of the measuring sytem caused by the influence is very small. It also became known that adjusting the azimuth of the analyser to 0” is effective for minimizing this error.
Optics & Laser Technology Vol24
No 3 1992