摘要:
An optical antenna includes an optical element mount (3) for mounting fiber ends (1a and 2a) of optical fibers (1 and 2) at different positions; and an optical transmitting and receiving system (4) for collimating, when laser beams are radiated from the fiber ends (1a and 2a), the laser beams to parallel light rays toward the space, and for focusing, when laser beams arrive from the space, the laser beams onto the fiber ends (1a and 2a) This makes it possible to set two optical transmitting and receiving directions 5 and 6 without installing complicated mechanical elements.
摘要:
An optical antenna includes an optical element mount (3) for mounting fiber ends (1a and 2a) of optical fibers (1 and 2) at different positions; and an optical transmitting and receiving system (4) for collimating, when laser beams are radiated from the fiber ends (1a and 2a), the laser beams to parallel light rays toward the space, and for focusing, when laser beams arrive from the space, the laser beams onto the fiber ends (1a and 2a) This makes it possible to set two optical transmitting and receiving directions 5 and 6 without installing complicated mechanical elements.
摘要:
An optical system deviation estimating apparatus includes an erected/inverted attitude setting means 9 for changing dispositional attitude of an optical system under test, a non-interferometric type wavefront measuring means 10 for measuring wavefronts at the attitudes as set up without resorting to interference phenomenon of light, a polynomial approximation means 15 for expanding measured wavefront values determined by the non-interferometric type wavefront measuring means 10 to a polynomial, an averaging arithmetic means 11 for averaging the measured values derived from output of the non-interferometric type wavefront measuring means 10 or alternatively arithmetic values derived from output of the polynomial approximation means 15, and a polynomial specific coefficient extraction arithmetic means 16 for extracting specific coefficient values of the polynomial.
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:
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:
A light wave radar apparatus includes a frequency deviation detecting unit 12 for detecting a frequency deviation fchirp of a light signal, and a weighted average processing unit 13 for determining a systematic error ΔVoffset from the frequency deviation fchirp detected by the frequency deviation detecting unit 12, and subtracts the systematic error ΔVoffset from a wind velocity VW calculated by a Doppler signal processing unit 11. As a result, the light wave radar apparatus can carry out a measurement of the wind velocity VW with a high degree of precision.
摘要:
An optical control type phased array antenna includes a laser generating means for generating light of single wavelength, an optical path branching means for branching the light emitted from the laser generating means into first and second transmission lights, a high frequency signal generating means for generating a high frequency signal, an optical frequency modulating means for shifting the frequency of the first transmission light branched by the optical path branching means by the frequency of a high frequency signal thus generated, a spatial light phase modulating means performing spatial phase modulation of the first transmission light shifted by the frequency of a high frequency signal depending on the antenna beam pattern, and an optical path branching/multiplexing means for multiplexing the first transmission light subjected to phase modulation and the second transmission light branched by the optical path branching means. Optical path lengths of two paths between the optical path branching means and the optical path branching/multiplexing means are equalized.
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.