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Generation and detection of squeezed light with a YAG laser
Abstracts FOG applications at JAE
F O G development status at Mitsubishi Precision Co, Lid
Eiichi Asami
Akihiro Kurokawa
J a p a n Aviation Electronics Industry Ltd.
Mitsubishi Precision Co, Ltd
9th Meeting on Lightwave Sensing Technology, Japanese Society of Lightwave Sensing Technology, J a p a n Society of Applied Physics
9th Meeting on Lightwave Sensing Technology, Japanese Society of Lightwave Sensing Technology, J a p a n Society of Applied Physics
Intermediate-grade FOGs and high-accuracy grade FOGs have been developing at JAE. These FOGs have closed-loop configurations which are realized by using integrated optics. We have also obtained the intermediate-grade (l°hr ' ~ 10°hr t) FOG for practical use. Some of our intermediate-grade FOGs are in practical use, for example rocket control systems, train positioning systems and another vehicle guidance systems. On the other hand, high-accuracy grade FOGs have been developing at JAE in order to realize the AHRS (Attitude Heading Reference System) for aerospace applications. In this paper, we introduce the development status of these FOGs and the applications at JAE.
In 1985, development of an interferometer type fibre-optic gyroscope (I-FOG) began at Mitsubishi Precision Co (MPC). As a result of comparing an I-FOG with conventional gyros, it was expected that an I-FOG, with low bias drift, wide dynamic range and environmental ruggedness, would become the main current gyro for the middle- and high-performance category during the 90s. At present, MPC has developed an open-loop and closed-loop I-FOG with 0.1 ~ 0.01 ° hr ' bias stability and a closed-loop I-FOG with 1° hr ' bias stability. The flight test of our open-loop I-FOG was successfully demonstrated on 22 February 1990 aboard the S-520-11 rocket of the Institute of Space Astronautical Science (ISAS) as a Roll Axis Rate Sensor. This paper presents a chronology of the development and performance of our FOGs.
Optical gyrocompass using a fibre-optic gyroscope with high resolution
Tatsuya Kumagai, Norihiro Ashizuka, Hisanori Nakai, Hiroshi Kajioka
Generation and detection of squeezed light with a YAG laser
Hitachi Cable Ltd.
J'Sehool of Engineering, Nagoya University, *Transmission Division, Fujitsu Ltd
9th Meeting o n Lightwave Sensing Technology, Japanese Society of Lightwave Sensing Technology, Japan Society of Applied Physics A fibre-optic gyroscope (FOG), based on the Sagnac effect, is an optical rotation sensor. This sensor resists vibration, starts quickly, and needs little power. These advantages over conventional gyroscopes result from the operational principle-optical interferometry. In recent years, the gyrocompass, which is compact, lightweight, maintenancefree and should have a long operating life is required for industrial and aerospace uses. If a FOG is used as a gyrocompass, however, it must measure the earth's rotation rate accurately and seek the direction of rotation axis. Moreover, it needs high sensitivity and low zero drift characteristics. Various types of FOGs have been designed and studied so far. This paper first describes the investigation of a high performance FOG, with the focus on an all-fibre gyroscope with phase modulation. Then, the performance of the optical gyrocompass is discussed.
N. Nishizawaf, M. Morit, T. Gotot, A. Miyauchi*
10th Meeting on Lightwave Sensing Technology, Japanese Society of Lightwave Sensing Technology, J a p a n Society of Applied Physics We demonstrate an experiment of squeezed light generation with the optical Kerr effect in an optical fibre. The squeezed vacuum is generated in a fibre ring reflector. It is necessary to tune the coupling ratio of the fibre coupler at 50% : 50% in order to observe the squeezed vacuum. A new tunable polarization maintaining optical fibre coupler, whose coupling ratio could be smoothly and finely tuned, is developed. A low-noise balanced homodyne detector, whose common noise reduction ratio is about 30 dB, is used. A very reproducible experimental configuration is made with the coupler and the detector. About 3 dB noise reduction is observed at low frequencies (100-350 kHz), although the noise level varies on a long-term scale.
Development of a fibre-optic gyroscope for wide applications
All-fibre gyroscope using output stabilization technique
Atsushi Watanabe, Hidehiko Negishi, Yoshihiko Honjoya, Yuko Takei, Toru Kanno
Ken-ichi Okada, Ryuji Usui
Matsushita Research Institute Tokyo, Inc. 9th Meeting on Lightwave Sensing Technology, Japanese Society of Lightwave Sensing Technology, Japan Society of Applied Physics A prototype of a fibre-optic gyroscope (FOG) with medium performance has been developed. This FOG is designed to support requirements from various applications such as mobile navigation systems and industrial robotics control. It is characterized by using a sensing loop of low birefringent single-mode fibre (length: 200 m), a Lyot type depolarizer and a laminated polarizer. The noise characteristic of this FOG was evaluated and it was found that the amplitude modulation (AM) noise from the phase modulator, which was the major source of zero bias drift, has particular phase characteristics. With the newly developed signal processing scheme, we have successfully eliminated the influence of the AM noise on zero bias drift and thus achieved a higher level of performance for a moderate FOG cost. Optics & Laser Technology VOl 25 No 4 1993
Japan Aviation Electronics Industry, Ltd 9th Meeting on Lightwave Sensing Technology, Japanese Society of Lightwave Sensing Technology, J a p a n Society of Applied Physics The open loop-type fibre-optic gyroscope is essentially influenced by the variation of the phase modulator characteristics and the optical power to the photodetector, and these cause the large scale-factor error and the rate output noise. We have designed a new signal processing using the second, the third and the fourth harmonic components of the phase modulation frequency. Thus, by automatically controlling the phase modulator characteristics, and furthermore, by compensating the optical power variation and the rate sine-output, the scale factor was remarkably stabilized. As a result, the performance of our experimental model (150m long and 0.04m mean radius: fibre coil) is the scale factor stability is within 5:0.03%, the scale factor linearity is within _+0.1%, and the bias temperature stability is less than 2° hr -L (hr) in the temperature range of -20°C ~ +70°C.
263
F O G development status at Mitsubishi Precision Co, Lid
Eiichi Asami
Akihiro Kurokawa
J a p a n Aviation Electronics Industry Ltd.
Mitsubishi Precision Co, Ltd
9th Meeting on Lightwave Sensing Technology, Japanese Society of Lightwave Sensing Technology, J a p a n Society of Applied Physics
9th Meeting on Lightwave Sensing Technology, Japanese Society of Lightwave Sensing Technology, J a p a n Society of Applied Physics
Intermediate-grade FOGs and high-accuracy grade FOGs have been developing at JAE. These FOGs have closed-loop configurations which are realized by using integrated optics. We have also obtained the intermediate-grade (l°hr ' ~ 10°hr t) FOG for practical use. Some of our intermediate-grade FOGs are in practical use, for example rocket control systems, train positioning systems and another vehicle guidance systems. On the other hand, high-accuracy grade FOGs have been developing at JAE in order to realize the AHRS (Attitude Heading Reference System) for aerospace applications. In this paper, we introduce the development status of these FOGs and the applications at JAE.
In 1985, development of an interferometer type fibre-optic gyroscope (I-FOG) began at Mitsubishi Precision Co (MPC). As a result of comparing an I-FOG with conventional gyros, it was expected that an I-FOG, with low bias drift, wide dynamic range and environmental ruggedness, would become the main current gyro for the middle- and high-performance category during the 90s. At present, MPC has developed an open-loop and closed-loop I-FOG with 0.1 ~ 0.01 ° hr ' bias stability and a closed-loop I-FOG with 1° hr ' bias stability. The flight test of our open-loop I-FOG was successfully demonstrated on 22 February 1990 aboard the S-520-11 rocket of the Institute of Space Astronautical Science (ISAS) as a Roll Axis Rate Sensor. This paper presents a chronology of the development and performance of our FOGs.
Optical gyrocompass using a fibre-optic gyroscope with high resolution
Tatsuya Kumagai, Norihiro Ashizuka, Hisanori Nakai, Hiroshi Kajioka
Generation and detection of squeezed light with a YAG laser
Hitachi Cable Ltd.
J'Sehool of Engineering, Nagoya University, *Transmission Division, Fujitsu Ltd
9th Meeting o n Lightwave Sensing Technology, Japanese Society of Lightwave Sensing Technology, Japan Society of Applied Physics A fibre-optic gyroscope (FOG), based on the Sagnac effect, is an optical rotation sensor. This sensor resists vibration, starts quickly, and needs little power. These advantages over conventional gyroscopes result from the operational principle-optical interferometry. In recent years, the gyrocompass, which is compact, lightweight, maintenancefree and should have a long operating life is required for industrial and aerospace uses. If a FOG is used as a gyrocompass, however, it must measure the earth's rotation rate accurately and seek the direction of rotation axis. Moreover, it needs high sensitivity and low zero drift characteristics. Various types of FOGs have been designed and studied so far. This paper first describes the investigation of a high performance FOG, with the focus on an all-fibre gyroscope with phase modulation. Then, the performance of the optical gyrocompass is discussed.
N. Nishizawaf, M. Morit, T. Gotot, A. Miyauchi*
10th Meeting on Lightwave Sensing Technology, Japanese Society of Lightwave Sensing Technology, J a p a n Society of Applied Physics We demonstrate an experiment of squeezed light generation with the optical Kerr effect in an optical fibre. The squeezed vacuum is generated in a fibre ring reflector. It is necessary to tune the coupling ratio of the fibre coupler at 50% : 50% in order to observe the squeezed vacuum. A new tunable polarization maintaining optical fibre coupler, whose coupling ratio could be smoothly and finely tuned, is developed. A low-noise balanced homodyne detector, whose common noise reduction ratio is about 30 dB, is used. A very reproducible experimental configuration is made with the coupler and the detector. About 3 dB noise reduction is observed at low frequencies (100-350 kHz), although the noise level varies on a long-term scale.
Development of a fibre-optic gyroscope for wide applications
All-fibre gyroscope using output stabilization technique
Atsushi Watanabe, Hidehiko Negishi, Yoshihiko Honjoya, Yuko Takei, Toru Kanno
Ken-ichi Okada, Ryuji Usui
Matsushita Research Institute Tokyo, Inc. 9th Meeting on Lightwave Sensing Technology, Japanese Society of Lightwave Sensing Technology, Japan Society of Applied Physics A prototype of a fibre-optic gyroscope (FOG) with medium performance has been developed. This FOG is designed to support requirements from various applications such as mobile navigation systems and industrial robotics control. It is characterized by using a sensing loop of low birefringent single-mode fibre (length: 200 m), a Lyot type depolarizer and a laminated polarizer. The noise characteristic of this FOG was evaluated and it was found that the amplitude modulation (AM) noise from the phase modulator, which was the major source of zero bias drift, has particular phase characteristics. With the newly developed signal processing scheme, we have successfully eliminated the influence of the AM noise on zero bias drift and thus achieved a higher level of performance for a moderate FOG cost. Optics & Laser Technology VOl 25 No 4 1993
Japan Aviation Electronics Industry, Ltd 9th Meeting on Lightwave Sensing Technology, Japanese Society of Lightwave Sensing Technology, J a p a n Society of Applied Physics The open loop-type fibre-optic gyroscope is essentially influenced by the variation of the phase modulator characteristics and the optical power to the photodetector, and these cause the large scale-factor error and the rate output noise. We have designed a new signal processing using the second, the third and the fourth harmonic components of the phase modulation frequency. Thus, by automatically controlling the phase modulator characteristics, and furthermore, by compensating the optical power variation and the rate sine-output, the scale factor was remarkably stabilized. As a result, the performance of our experimental model (150m long and 0.04m mean radius: fibre coil) is the scale factor stability is within 5:0.03%, the scale factor linearity is within _+0.1%, and the bias temperature stability is less than 2° hr -L (hr) in the temperature range of -20°C ~ +70°C.
263