摘要:
To obtain a coherent laser radar device that realizes high reliability and the high output of a transmitted light, the device includes a first optical coupler that branches a laser beam from a laser source into two lights, a local light and a transmitted light, an optical modulator that modulates the transmitted light, a space type optical amplifier that amplifies the modulated transmitted light, a transmitting/receiving optical system that applies the amplified transmitted light toward a target and receives a scattered light from the target, a transmitting/receiving light splitting device that splits the transmitted light and the received light, a second optical coupler that mixes the local light and the split received light together, a photodetector that detects heterodyne of a mixed light, a beat signal amplifier that amplifies a detected signal, a signal processing device that processes an amplified signal, and a display device that displays a processed result. The first and second optical couplers and an optical modulator are structured by polarization maintained type optical elements, and an optical path that extends from the laser source to the space type optical amplifier through the first optical coupler, an optical path that extends from the transmitting/receiving light splitting device to the photodetector through the second optical coupler, and an optical path that extends from the first optical coupler to the second optical coupler are connected by polarization maintained type single mode optical fibers.
摘要:
To obtain a coherent laser radar device that realizes high reliability and the high output of a transmitted light, the device includes a first optical coupler that branches a laser beam from a laser source into two lights, a local light and a transmitted light, an optical modulator that modulates the transmitted light, a space type optical amplifier that amplifies the modulated transmitted light, a transmitting/receiving optical system that applies the amplified transmitted light toward a target and receives a scattered light from the target, a transmitting/receiving light splitting device that splits the transmitted light and the received light, a second optical coupler that mixes the local light and the split received light together, a photodetector that detects heterodyne of a mixed light, a beat signal amplifier that amplifies a detected signal, a signal processing device that processes an amplified signal, and a display device that displays a processed result. The first and second optical couplers and an optical modulator are structured by polarization maintained type optical elements, and an optical path that extends from the laser source to the space type optical amplifier through the first optical coupler, an optical path that extends from the transmitting/receiving light splitting device to the photodetector through the second optical coupler, and an optical path that extends from the first optical coupler to the second optical coupler are connected by polarization maintained type single mode optical fibers.
摘要:
A lidar includes CW laser light sources that oscillate CW laser light rays with wavelengths different from each other; an optical multiplexing coupler that mixes the CW laser light rays oscillated by the CW laser light sources; an optical branching coupler that splits the CW laser light passing through the mixing by the optical multiplexing coupler; a light modulator that modulates first CW laser light split by the optical branching coupler; and an optical fiber amplifier that amplifies the laser light modulated by the light modulator, in which a transmit-receive optical system irradiates a target with the laser light amplified by the optical fiber amplifier, and receives scattered light of the laser light by the target.
摘要:
A lidar includes CW laser light sources that oscillate CW laser light rays with wavelengths different from each other; an optical multiplexing coupler that mixes the CW laser light rays oscillated by the CW laser light sources; an optical branching coupler that splits the CW laser light passing through the mixing by the optical multiplexing coupler; a light modulator that modulates first CW laser light split by the optical branching coupler; and an optical fiber amplifier that amplifies the laser light modulated by the light modulator, in which a transmit-receive optical system irradiates a target with the laser light amplified by the optical fiber amplifier, and receives scattered light of the laser light by the target.
摘要:
In the measurement system for an aircraft according to the present invention, the three-axis components of the airspeed of the aircraft, the three-axis components of the wind speed currently encountered by the aircraft, and the wind speed distribution ahead of the aircraft, are measured simultaneously, by providing a Doppler anemometer which measures the airflow speeds at a plurality of points separated by a prescribed distance in the beam irradiation direction, and an inertial data measurement device which measures the movement information and positional information of the aircraft. Furthermore, in the measurement system for an aircraft according to the present invention, the measurement accuracy of the device is improved by providing means for obtaining information the movement and positional information of the aircraft during measurement, from the inertial data measurement device, and for correcting the measurement values from the Doppler anemometer by means of the information.
摘要:
A laser radar apparatus includes a mixer 12 for converting the frequency of an electric signal outputted from a photodetector 11 into a baseband frequency by using a modulating signal generated by an oscillator 2. The laser radar apparatus carries out a coherent integral of the electric signal whose frequency has been converted by the mixer 12, and measures the quality of scatterers which exist in the atmosphere from a result of the integral. As a result, even when the S/N ratio of the light signal received by a receiving optical unit 8 is low, the laser radar apparatus can detect the quality of the scatterers.
摘要:
A measurement system for an aircraft having the three-axis components of the airspeed of the aircraft, the three-axis components of the wind speed currently encountered by the aircraft, and the wind speed distribution ahead of the aircraft simultaneously in real time. It comprises a Doppler anemometer measuring the airflow speeds at a plurality of points separated by a prescribed distance in the beam irradiation direction that changes in a time series, and an inertial data measurement device measuring the movement information and positional information of the aircraft. Moreover, the display system of the aircraft includes the horizontal two-axis airspeed of the aircraft, the three-axis components of the wind speed currently encountered by the aircraft, and information on the wind speed distribution ahead of the aircraft are displayed simultaneously in real time.
摘要:
A laser radar apparatus includes a mixer 12 for converting the frequency of an electric signal outputted from a photodetector 11 into a baseband frequency by using a modulating signal generated by an oscillator 2. The laser radar apparatus carries out a coherent integral of the electric signal whose frequency has been converted by the mixer 12, and measures the quality of scatterers which exist in the atmosphere from a result of the integral. As a result, even when the S/N ratio of the light signal received by a receiving optical unit 8 is low, the laser radar apparatus can detect the quality of the scatterers.
摘要:
An optical wavelength conversion element includes: a wavelength conversion waveguide that has a periodic polarization reversal structure having alternately and cyclically formed domains of which polarization directions are inverted, that guides light as a fundamental wave corresponding to the periodic polarization reversal structure, and performs a wavelength conversion of the guided fundamental wave; a first clad that is made of a dielectric having a refractive index lower than that of the wavelength conversion waveguide and is provided in contact with the domains; a second clad that is made of a dielectric having a refractive index lower than that of the wavelength conversion waveguide and is provided in contact with the domains such that the second clad is opposed to the first clad film; a first conducting unit that electrically connects the domains in parallel via the first clad; and a second conducting unit that electrically connects the domains in parallel via the second clad.
摘要:
An optical wavelength conversion element includes: a wavelength conversion waveguide that has a periodic polarization reversal structure having alternately and cyclically formed domains of which polarization directions are inverted, that guides light as a fundamental wave corresponding to the periodic polarization reversal structure, and performs a wavelength conversion of the guided fundamental wave; a first clad that is made of a dielectric having a refractive index lower than that of the wavelength conversion waveguide and is provided in contact with the domains; a second clad that is made of a dielectric having a refractive index lower than that of the wavelength conversion waveguide and is provided in contact with the domains such that the second clad is opposed to the first clad film; a first conducting unit that electrically connects the domains in parallel via the first clad; and a second conducting unit that electrically connects the domains in parallel via the second clad.