Abstract: Provided is a light beam incident device including an off-axis parabolic mirror that receives parallel light beams and converges the parallel light beams at one point on an object to be measured, and an incident-side light reception surface of a mirror that feeds the parallel light beams to the off-axis parabolic mirror. An angle (incident angle) between the object to be measured and converged light beams obtained by converging the parallel light beams changes in accordance with a light reception portion at which the off-axis parabolic mirror receives the parallel light beams. The incident side light reception surface of the mirror can change the light reception portion by moving with respect to the off-axis parabolic mirror.

Abstract: A pulse light source includes: a master laser that outputs a master laser light pulse whose repetition frequency is controlled to a predetermined value; a slave laser that outputs a slave laser light pulse; a phase comparator that detects a phase difference between an electric signal having a frequency of the predetermined value, and an electric signal based on a light intensity of the slave laser light pulse; a loop filter; an adder that adds a repetition frequency control signal having a certain repetition cycle, to an output from the loop filter; and a phase comparator that measures a pulse phase difference which is a phase difference between the master laser light pulse and the slave laser light pulse. A magnitude of the repetition frequency control signal is controlled such that the measured pulse phase difference matches with a target value of the pulse phase difference.

Abstract: An electromagnetic wave measurement device includes an electromagnetic wave outputter that outputs an electromagnetic wave having a frequency equal to or more than 0.01 THz and equal to or less than 100 THz toward a device under test. An electromagnetic wave detector detects the electromagnetic wave which has transmitted through the device under test. A relative position changer changes a relative position of an intersection of an optical path of the electromagnetic wave transmitting through the device under test and the device under test, with respect to the device under test, so that the intersection is at a predetermined relative position due to the refraction of the electromagnetic wave by the device under test. A characteristic value deriver derives a characteristic value of the electromagnetic wave based on a detection result of the electromagnetic wave detector, the characteristic value being associated with the predetermined relative position.

Abstract: A pulse light source includes: a master laser that outputs a master laser light pulse whose repetition frequency is controlled to a predetermined value; a slave laser that outputs a slave laser light pulse; a phase comparator that detects a phase difference between an electric signal having a frequency of the predetermined value, and an electric signal based on a light intensity of the slave laser light pulse; a loop filter; an adder that adds a repetition frequency control signal having a certain repetition cycle, to an output from the loop filter; and a phase comparator that measures a pulse phase difference which is a phase difference between the master laser light pulse and the slave laser light pulse. A magnitude of the repetition frequency control signal is controlled such that the measured pulse phase difference matches with a target value of the pulse phase difference.

Abstract: Provided is a light beam incident device including an off-axis parabolic mirror that receives parallel light beams and converges the parallel light beams at one point on an object to be measured, and an incident-side light reception surface of a mirror that feeds the parallel light beams to the off-axis parabolic mirror. An angle (incident angle) between the object to be measured and converged light beams obtained by converging the parallel light beams changes in accordance with a light reception portion at which the off-axis parabolic mirror receives the parallel light beams. The incident side light reception surface of the mirror can change the light reception portion by moving with respect to the off-axis parabolic mirror.

Abstract: According to the repetition frequency control device, a master laser outputs a master laser light pulse the repetition frequency of which is controlled to a predetermined value. A slave laser outputs a slave laser light pulse. A reference comparator compares a voltage of a reference electric signal the repetition frequency of which is the predetermined value and a predetermined voltage with each other, thereby outputting a result thereof. A measurement comparator compares a voltage based on a light intensity of the slave laser light pulse and the predetermined voltage with each other, thereby outputting a result thereof. A phase difference detector detects a phase difference between the output from the reference comparator and the output from the measurement comparator. A loop filter removes a high-frequency component of an output from the phase difference detector.

Abstract: A frequency converter includes a first direct digital synthesizer that receives a signal having a predetermined frequency f_master as a clock signal and further an internal frequency setting signal, and outputs an internal signal having a frequency based on the internal frequency setting signal, and a second direct digital synthesizer that receives the internal signal as a clock signal, and further an output frequency setting signal, and outputs an output signal having a frequency f_slave (=f_master??) based on the output frequency setting signal. A difference between the predetermined frequency f_master and the frequency of the internal signal is larger than a difference between the predetermined frequency f_master and the frequency f_slave of the output signal.

Abstract: An electromagnetic wave measurement device includes an electromagnetic wave outputter that outputs an electromagnetic wave having a frequency equal to or more than 0.01 THz and equal to or less than 100 THz toward a device under test. An electromagnetic wave detector detects the electromagnetic wave which has transmitted through the device under test. A relative position changer changes a relative position of an intersection of an optical path of the electromagnetic wave transmitting through the device under test and the device under test, with respect to the device under test, so that the intersection is at a predetermined relative position due to the refraction of the electromagnetic wave by the device under test. A characteristic value deriver derives a characteristic value of the electromagnetic wave based on a detection result of the electromagnetic wave detector, the characteristic value being associated with the predetermined relative position.

Abstract: A detector detects an electromagnetic wave having a frequency of 0.01 THz?f?100 THz and transmitted through a device under test (DUT). A changer changes a relative position of an intersection of an optical path of the electromagnetic wave and the DUT, with respect to the DUT. A deriver derives a characteristic value of the electromagnetic wave based on a detection result of the detector, while the characteristic value is associated with an assumed relative position, which is the relative position if the electromagnetic wave is not refracted by the DUT. A corrector changes the assumed relative position to an actual relative position, which is the relative position if the refraction of the electromagnetic wave by the DUT is considered. A corrected deriver derives the characteristic value associated with a predetermined relative position based on an output from the corrector.

Abstract: According to the present invention, an electromagnetic wave measurement device includes an electromagnetic wave output device, an electromagnetic wave detector, a relative position changing unit, a delay period recording unit, a phase deriving unit, a delay-corrected phase deriving unit, a sinogram deriving unit, and an image deriving unit. The electromagnetic wave output device outputs an electromagnetic wave having a frequency equal to or more than 0.01 THz and equal to or less than 100 THz toward a device under test and a container storing at least a part of the device under test.

Abstract: A repetition frequency control device includes a slave photoelectric conversion unit which converts a slave laser light pulse into a slave electrical signal, a master photoelectric conversion unit which converts a master laser light pulse into a master electrical signal, a frequency change unit which changes the repetition frequency of the master electric signal by a predetermined value, a phase comparator which detects a phase difference between the slave electric signal and the output from the frequency change unit, and a loop filter which removes a high frequency component of an output from the phase comparator, where the repetition frequency of the master laser does not undergo control based on one or both of the master electric signal and the slave electric signal.

Abstract: An object is to enable a change in a frequency for which an electric signal based on an optical signal is measured by a spectrum analyzer. An optical measurement device includes a first photoconductive switch that receives predetermined pulse light from a first laser light source, and outputs terahertz light having the same repetition frequency as the repetition frequency of the predetermined pulse light. The optical measurement device also includes a second photoconductive switch that receives the terahertz light and a sampling light pulse, and outputs a signal corresponding to a power of the terahertz light at a time point when the sampling light pulse is received.

Abstract: According to the repetition frequency control device, a master laser outputs a master laser light pulse the repetition frequency of which is controlled to a predetermined value. A slave laser outputs a slave laser light pulse. A reference comparator compares a voltage of a reference electric signal the repetition frequency of which is the predetermined value and a predetermined voltage with each other, thereby outputting a result thereof. A measurement comparator compares a voltage based on a light intensity of the slave laser light pulse and the predetermined voltage with each other, thereby outputting a result thereof. A phase difference detector detects a phase difference between the output from the reference comparator and the output from the measurement comparator. A loop filter removes a high-frequency component of an output from the phase difference detector.

Abstract: A repetition frequency control device includes a slave photoelectric conversion unit which converts a slave laser light pulse into a slave electrical signal, a master photoelectric conversion unit which converts a master laser light pulse into a master electrical signal, a frequency change unit which changes the repetition frequency of the master electric signal by a predetermined value, a phase comparator which detects a phase difference between the slave electric signal and the output from the frequency change unit, and a loop filter which removes a high frequency component of an output from the phase comparator, where the repetition frequency of the master laser does not undergo control based on one or both of the master electric signal and the slave electric signal.

Abstract: According to the present invention, the CT is carried out based on parameters other than the absorption rate. An electromagnetic wave measurement device includes an electromagnetic wave output device 2 which outputs an electromagnetic wave at a frequency equal to or more than 0.

Abstract: According to the present inventions, a phase control device for laser light pulse includes a laser, a reference comparator, a measurement comparator, a phase difference detector and a loop filter. The laser outputs a laser light pulse. The reference comparator compares a voltage of a reference electric signal having a predetermined frequency and a predetermined voltage with each other, thereby outputting a result thereof. The measurement comparator compares a voltage based on a light intensity of the laser light pulse and a voltage of a measurement electric signal having the predetermined frequency, with a voltage of a phase control signal, thereby outputting a result thereof. The phase difference detector detects a phase difference between the output from the reference comparator and the output from the measurement comparator. The loop filter removes a high frequency component of an output from the phase difference detector.

Abstract: A frequency converter includes a first direct digital synthesizer that receives a signal having a predetermined frequency f_master as a clock signal and further an internal frequency setting signal, and outputs an internal signal having a frequency based on the internal frequency setting signal, and a second direct digital synthesizer that receives the internal signal as a clock signal, and further an output frequency setting signal, and outputs an output signal having a frequency f_slave (=f_master??) based on the output frequency setting signal. A difference between the predetermined frequency f_master and the frequency of the internal signal is larger than a difference between the predetermined frequency f_master and the frequency f_slave of the output signal.

Abstract: According to the present invention, an electromagnetic wave measurement device includes an electromagnetic wave output device, an electromagnetic wave detector, a relative position changing unit, a delay period recording unit, a phase deriving unit, a delay-corrected phase deriving unit, a sinogram deriving unit, and an image deriving unit. The electromagnetic wave output device outputs an electromagnetic wave having a frequency equal to or more than 0.01 [THz] and equal to or less than 100 [THz] toward a device under test and a container storing at least a part of the device under test. The electromagnetic wave detector detects the electromagnetic wave which has transmitted through the device under test. The relative position changing unit changes a relative position of an intersection at which an optical path of the electromagnetic wave transmitting through the device under test and the device under test intersect with respect to the device under test.

Abstract: According to the electromagnetic wave measurement device of the present invention, an electromagnetic wave output device outputs an electromagnetic wave having a frequency equal to or more than 0.01 [THz] and equal to or less than 100 [THz] toward a device under test. An electromagnetic wave detector detects the electromagnetic wave which has transmitted through the device under test. A relative position changing unit changes a relative position of an intersection across which an optical path of the electromagnetic wave transmitting through the device under test and the device under test intersect with respect to the device under test. A characteristic value deriving unit derives a characteristic value of the electromagnetic wave based on a detection result of the electromagnetic wave detector while the characteristic value is associated with an assumed relative position which is the relative position if it is assumed that the electromagnetic wave is not refracted by the device under test.

Abstract: According to the present invention, the CT is carried out based on parameters other than the absorption rate. An electromagnetic wave measurement device includes an electromagnetic wave output device 2 which outputs an electromagnetic wave at a frequency equal to or more than 0.