JP2015127718A - Sub-millimeter wave proximate field measuring device having high precision non-contact position measuring mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system and a method for measuring the distribution of electromagnetic intensities of sub-millimeter wave beams without being affected by errors ensuing from the setup of optical constituent elements and moreover in a non-contact way.SOLUTION: Three or more collimated light reflectors are arranged in a sub-millimeter wave beam receiver, and any misalignment between a transmission system and a receiver optical system is determined on the basis of the receiving positions of collimated light beams transmitted from a collimator and reflected by the reflectors; a distribution of electromagnetic intensities of sub-millimeter wave beams received by the receiver optical system, cleared of any influence of misalignment, is determined by correction using the misalignment.

Description

  The present invention relates to a system and method for measuring the electromagnetic intensity distribution of a submillimeter wave beam. In particular, the present invention realizes the mechanical positioning of the submillimeter wave beam receiving optical system with respect to the coordinate system that defines the near field of the submillimeter wave beam transmitter with high accuracy and non-contact, thereby providing a submillimeter wave beam for the coordinate system. The present invention relates to a system and method for determining an electromagnetic intensity distribution after removing the influence of a shift and tilt of a receiving optical system.

  Electromagnetic waves with a wavelength of 1mm to 0.1mm are called submillimeter waves. Elucidation of phenomena in space such as supernova explosions and celestial formation, and ozone layer destruction mechanism by detecting trace substances such as ClO and HCl contained in the stratospheric atmosphere Such researches are mainly observed and used for academic research purposes.

  Since submillimeter waves have a shorter wavelength than microwaves, in order to achieve low-loss and wideband signal transmission in the submillimeter wave band, the mechanical accuracy of the antenna and optical system used is higher than before. Imposed. Moreover, it is necessary to strictly manage manufacturing errors caused by individual dependence in each optical element. In order to meet these requirements, it is difficult to design the shape, inclination, and position of optical elements such as various mirrors and manage their error distribution compared to the design and management of mirrors used in the microwave band. It is.

  Submillimeter wave observation has come to be used as the above research method relatively recently, and submillimeter wave utilization and measurement technologies are still in the development stage. There are many performance parameters that cannot be determined at the time of designing and manufacturing optical elements (reflection loss, etc.). For this reason, in order to evaluate the performance of the antenna and optical system to be used in the submillimeter wave band, it is not sufficient to mechanically measure the shape, position, etc. of each optical element constituting them. In contrast, the sub-millimeter wave electromagnetic field characteristics (beam direction, beam diameter, beam spreading method) are actually measured using the optical elements, such as transmitting a sub-millimeter wave beam and determining its electromagnetic field characteristics by three-dimensional distribution measurement. It is necessary to measure.

  However, when measuring the electromagnetic field characteristics of a submillimeter wave beam, a manufacturing error of a measurement object (an optical element such as a mirror) constituting the submillimeter wave beam reception optical system, or a submillimeter wave beam reception optical including the measurement object. The assembly error of the system and the submillimeter wave beam transmission system including the submillimeter wave beam transmitter cannot be ignored. That is, in the near-field measurement in a long wavelength band such as a microwave band, the mechanical tolerances are maintained and managed at the time of designing the transmission system and the reception optical system, so that the target accuracy is sufficiently met. In contrast to this, in the near-field measurement in the submillimeter wave band with a wavelength of 1 mm or less, it is not possible to eliminate it by maintenance before the measurement. Even small errors can have a negligible effect on the measurement results.

  For example, in order to determine the electromagnetic field characteristics (beam width, center position, pointing direction, etc.) of a submillimeter wave beam with respect to the mechanical reference of the submillimeter wave beam transmission system, the submillimeter wave beam is received using the submillimeter wave beam receiving optical system. It is necessary to receive the beam and measure the electromagnetic intensity distribution in the three-dimensional space of the submillimeter wave beam. Here, the misalignment (relative position) between the submillimeter wave beam transmitting system and the submillimeter wave beam receiving optical system is required. , Deviation from the design value of the orientation), the measured intensity distribution changes apparently. However, it is difficult to discriminate only from the measured intensity distribution whether such a change in intensity distribution is due to the characteristics of the beam itself or only an apparent change due to misalignment. On the other hand, as already mentioned, it is impossible to remove all the errors that affect the near-field measurement in the submillimeter wave band before the measurement, and the measurement result of the intensity distribution is apparent due to such misalignment. It is inevitable that the above changes are included.

  On the other hand, in order to obtain an intensity distribution measurement result in which such apparent changes are eliminated, the electromagnetic intensity distribution of the submillimeter wave beam was measured using a transmission system and a reception optical system having misalignment with each other. After that, it is effective to remove the influence of the misalignment by correcting the measured intensity distribution according to the misalignment. For that purpose, a technique for measuring the alignment between the transmission system and the reception optical system separately from the measurement of the submillimeter wave beam and determining the misalignment is required. In particular, by setting the distance between the transmission system and the reception optical system to various values and scanning the two-dimensional plane using the transmitter while fixing the reception optical system, the submillimeter wave beam for the various distances is scanned. In an embodiment in which a two-dimensional in-plane electromagnetic intensity distribution is measured and a submillimeter wave beam electromagnetic intensity distribution in a three-dimensional space is determined as a set of such two-dimensional in-plane distributions, (i) a receiving optical system Three-dimensional information about the relative position and orientation between the mechanical reference of (ii) and the two-dimensional measurement grid to be scanned by the transmitter, as defined by the transmission system, before the measurement of the electromagnetic intensity distribution. A technique for determining with an accuracy of 10 μm or less is required. In addition, as a prior art related to the measurement of such an alignment, there is a remote displacement measuring device described in Patent Document 1, which is a patented invention used for measuring the mirror surface accuracy of a reflecting mirror product. It is not directly related to the problem to be solved by the invention.

  In addition, when measuring the alignment between equipment and parts used in research in the aerospace field, such measurement can be performed without mechanically contacting the equipment and parts with the alignment measuring device. It is desirable. If mechanical contact occurs, equipment and parts may be damaged. For example, various parts mounted on satellites cannot be easily repaired or replaced at the operation stage in space. Such contact should avoid mechanical damage to the parts.

Japanese Patent No. 2788281

  In view of the above, a technique for determining misalignment with high accuracy by measuring the alignment between the submillimeter wave beam transmitting system and the submillimeter wave beam receiving optical system in a non-contact manner, and the electromagnetic of the submillimeter wave beam There is a need for a technique for determining the intensity distribution from which the influence of the misalignment is removed by correcting the intensity distribution measurement result according to the misalignment.

  In order to achieve the above object, the present invention provides a collimator comprising: a collimator light transmitter that transmits collimated light; and a reflected light receiver that receives reflected light; A sub-millimeter wave beam receiving section including three or more collimated light reflectors that reflect the collimated light transmitted from the light transmitting section, and a sub-millimeter wave beam receiving optical system, and predetermined coordinates that define the emission position of the collimated light A position determining unit that determines a position where light reflected by any of the three or more collimated light reflectors in the system is received, and reflected by the three or more collimated light reflectors respectively determined by the position determining unit. The position of the submillimeter wave beam receiving unit in a predetermined coordinate system and the geometric orientation of the submillimeter wave beam receiving unit with respect to the predetermined coordinate system using the received light receiving position A position and geometric orientation calculating unit, a submillimeter wave beam transmitting unit for transmitting a submillimeter wave beam, and a submillimeter wave beam receiving unit using a submillimeter wave beam receiving optical system. Measuring the electromagnetic intensity of the submillimeter wave beam received by the submillimeter wave beam measuring section, the electromagnetic intensity of the submillimeter wave beam measured by the submillimeter wave beam measuring section, and the emission position of the submillimeter wave beam in the coordinate system And the position and geometric orientation of the submillimeter wave beam receiver calculated by the position and geometric orientation calculator, and the submillimeter wave beam transmitted from the submillimeter wave beam transmitter in the coordinate system. An intensity distribution determining unit for determining an electromagnetic intensity distribution, thereby providing a position and geometry of the submillimeter wave beam receiving unit. The electromagnetic intensity in the coordinate system of the submillimeter wave beam transmitted from the submillimeter wave beam transmitter after correction corresponding to the apparent change in the electromagnetic intensity distribution of the submillimeter wave beam that occurs depending on the local orientation Provided is a submillimeter wave beam measurement system characterized by determining a distribution.

Using the above system,
(1) While moving the collimator in a predetermined coordinate system, the collimated light is transmitted to each collimated light reflector disposed at a predetermined position with respect to the submillimeter wave beam receiving unit, and each collimated light reflector The light reflected from the collimator is received by the collimator, the position coordinates of the collimated light reflector in the coordinate system are determined from the light receiving position, and the position coordinates are fitted to, for example, a translation or rotation model of a rigid body. Then, the alignment between the system including the submillimeter wave beam transmission unit (submillimeter wave beam transmission system) and the submillimeter wave beam receiving optical system is calculated, and the misalignment is determined as the difference between the design value and the actual measurement value in the alignment.
(2) While maintaining the alignment between the transmission system and the reception optical system when the step (1) is performed, the submillimeter wave beam reception optics is continuously moved while moving the submillimeter wave beam transmission unit within the predetermined coordinate system. By transmitting the submillimeter wave beam to the system and measuring the electromagnetic intensity of the submillimeter wave beam received using the receiving optical system, the electromagnetic intensity distribution of the submillimeter wave beam in the coordinate system is measured.
(3) Further, the electromagnetic intensity distribution is corrected using the misalignment determined in (1) above.
By this process, it is possible to determine the electromagnetic intensity distribution of the submillimeter wave beam after eliminating the apparent change due to misalignment. Note that the predetermined coordinate system here is typically a two-dimensional coordinate system that defines a two-dimensional plane to be scanned by the submillimeter wave beam transmitter, but the system of the present invention can be applied to any other coordinate system. It is also possible to configure.

  In the step (1), it is not essential to move the collimator in the coordinate system. For example, a large apparatus that covers the entire measurement target area in the coordinate system may be used as a collimator, and collimated light may be emitted from an arbitrary position in the coordinate system. Regarding the light receiving position of the reflected light in the collimator, a light receiving element such as a CCD is arranged in such a large collimator so as to cover the measurement target region, and a signal from the element that has received the reflected light is read out. Can be determined without moving. Similarly, it is not essential to move the submillimeter wave beam transmitter in the coordinate system in the step (2).

  Alternatively, the system of the present invention is a system for determining the position of the specimen in a predetermined coordinate system and the geometric orientation of the specimen with respect to the predetermined coordinate system, and a collimated light transmitter for transmitting collimated light; A collimator including a reflected light receiving unit that receives the reflected light, and three or more collimated lights that are arranged at predetermined positions with respect to the specimen and reflect the collimated light transmitted from the collimated light transmitting unit A position determining unit for determining a position at which light reflected by any of the three or more collimated light reflectors is received in a predetermined coordinate system that defines an emission position of the collimated light; and a position determining unit Using the light receiving positions of the light reflected by the three or more collimated light reflectors determined by the above, the position of the specimen in a predetermined coordinate system, and the predetermined coordinate system Calculating the geometric orientation of the specimen, the position and the geometrical orientation calculation unit may be configured as a system comprising a.

  In particular, the system includes a configuration for determining misalignment between the transmission system and the reception optical system by the step (1). If this system is used, the position and geometric orientation of the specimen relative to a predetermined coordinate system can be measured with high accuracy by a non-contact method. In the conventional measurement using an autocollimator, the relative inclination of the specimen with respect to a predetermined coordinate system could be determined in a non-contact manner, but both the relative position and the relative inclination were not in contact as in the present invention. It was impossible to make a decision at the same time.

  The specimen may be a measurement target wavelength band light beam receiving unit including a measurement target wavelength band light beam receiving optical system. The system of the present invention can be configured as a system for determining the position of such a specimen in a predetermined coordinate system and the geometric orientation with respect to the predetermined coordinate system. In such a system, the measurement target wavelength band light beam transmission unit that transmits the measurement target wavelength band light beam and the measurement target wavelength band light beam transmission unit that transmits the measurement target wavelength band light beam is used. The measurement target wavelength band light beam measurement unit that measures the electromagnetic intensity of the measurement target wavelength band light beam received by the measurement target wavelength band light beam receiver, and the measurement measured by the measurement target wavelength band light beam measurement unit. The electromagnetic intensity of the target wavelength range light beam, the emission position of the measurement target wavelength range light beam in the coordinate system, the position of the measurement target wavelength range light beam reception unit calculated by the position and geometric orientation calculation unit, and And determining the electromagnetic intensity distribution in the coordinate system of the measurement target wavelength band light beam transmitted from the measurement target wavelength band light beam transmitter using the geometric orientation. And a determination unit may further include. If such a system is used, a correction corresponding to the apparent change in the measurement target wavelength region light beam electromagnetic intensity distribution, which occurs depending on the position and geometric orientation of the measurement target wavelength region light beam receiver, is performed. In addition, the electromagnetic intensity distribution in the coordinate system of the measurement target wavelength band light beam transmitted from the measurement target wavelength band light beam transmission unit can be determined.

  The system of the present invention is not limited to the submillimeter wave band, and can be configured as a system for determining the electromagnetic intensity distribution of a beam belonging to an arbitrary wavelength range to be measured.

  On the other hand, the measurement target wavelength band light beam transmission unit may be a submillimeter wave beam transmission unit that transmits a submillimeter wave beam, and the measurement target wavelength band light beam reception unit includes a submillimeter wave beam reception optical system. It may be a submillimeter wave beam receiver.

  As already mentioned, slight errors accompanying the setup that cannot be eliminated by maintenance before measurement affect the measurement in the high frequency band such as the submillimeter wave band. Is particularly useful for performing high-precision beam measurement while eliminating the apparent change that such errors have on the measurement results.

  In the system of the present invention, the moving mechanism unit moves the collimator and the measurement target wavelength band light beam transmission unit in the coordinate system, and changes the distance between the collimator and the measurement target wavelength band light beam transmission unit and the specimen. Can be further provided. Further, the position where the reflected light is received is determined based on the information on the movement of the collimator in the coordinate system by the moving mechanism unit, and the coordinate system of the light beam transmitting unit to be measured by the moving mechanism unit. The position determination unit can be configured to determine the emission position of the measurement target wavelength band light beam in the coordinate system based on the information regarding the movement within the coordinate system.

In the steps (1) and (2), any device can be used as the moving mechanism unit that moves the collimator or the submillimeter wave beam transmitting unit within a predetermined coordinate system. As an example, as described in the embodiments below,
(I) A base on which a collimator or a submillimeter wave beam transmission unit can be installed is slidably attached to a first direction shaft portion extending in a first direction defining the predetermined coordinate system,
(Ii) One end of the first direction shaft portion is slidably attached to a second direction shaft portion that is orthogonal to the first direction and extends in a second direction that defines the coordinate system together with the first direction,
(Iii) Use a moving mechanism configured by slidably attaching the second direction shaft portion to a third direction shaft portion extending in a third direction orthogonal to the first direction and the second direction. Can do.
If such a moving mechanism part is used, after installing a collimator or a submillimeter wave beam transmitting part in the base, the base is slid with respect to the first direction axis part, and the first direction axis part is further changed to the second direction axis part. The collimator or the submillimeter wave beam transmitter can be moved to an arbitrary position in the predetermined coordinate system, and is attached to the second direction shaft (and attached to the second direction shaft). The distance between the collimator or the submillimeter wave beam transmitting unit and the specimen can be changed by sliding the first direction shaft portion) with respect to the third direction shaft portion.

  Further, by acquiring the length of sliding of the base or the corresponding another shaft portion with respect to each shaft portion, the movement in the coordinate system in the collimator or the submillimeter wave beam transmitting portion, and the collimator or the submillimeter wave beam If a position determining unit that determines a change in the distance between the transmitting unit and the specimen is connected to the moving mechanism unit, the reflected light receiving position is determined based on the position of the collimator when the collimator receives the reflected light. Furthermore, the submillimeter wave beam emission position can be determined based on the position of the submillimeter wave beam transmission unit when the submillimeter wave beam is transmitted. The same applies to the case where an arbitrary measurement target wavelength band light beam transmission unit is used instead of the submillimeter wave beam transmission unit.

  In the system of the present invention, using the electromagnetic intensity distribution in the coordinate system of the measurement target wavelength band light beam determined by the intensity distribution determination unit, the beam center position of the measurement target wavelength band light beam in the coordinate system, and Each of the electromagnetic intensity distributions determined by the intensity distribution determining unit while changing the distance between the measurement target wavelength region light beam transmitting unit and the specimen by the first statistical analysis means for determining the beam width and the moving mechanism unit. A statistical analysis unit having a second statistical analysis unit that determines a propagation vector direction and a beam offset of a light beam to be measured in the wavelength band using each beam center position determined by the first statistical analysis unit. Can be further provided.

  As will be described later in the examples, by performing statistical analysis using the two-dimensional Gaussian distribution model on the electromagnetic intensity distribution of the beam obtained by measurement, the center position of the beam in the coordinate system, the beam Beam parameters such as width can be determined. Furthermore, while changing the distance between the light beam transmitter for the wavelength to be measured and the test piece in various ways, performing the beam measurement while maintaining the respective distances to determine the electromagnetic intensity distribution in the coordinate system. If the beam center position corresponding to each distance is determined by the above statistical analysis, the propagation vector direction of the light beam to be measured is typically determined as the direction of a straight line approximating the set of beam center positions. The beam offset can be determined as the virtual beam center position in the coordinate system when the distance between the beam transmission unit and the specimen is zero using the straight line.

  The reflected light receiving unit may be further configured to measure the intensity of the received reflected light. In addition, the position and geometric orientation calculation unit 3 in the coordinate system is based on two or more light reception positions determined by the position determination unit to be a position where reflected light having an intensity equal to a predetermined threshold is received. The position of each of the collimated light reflectors is determined, and the position of the specimen in the predetermined coordinate system and the predetermined coordinate system are determined using the determined positions of the three or more collimated light reflectors. May be configured to calculate the geometric orientation of the specimen relative to.

  The above configuration is an example for calculating the position and geometric orientation of the specimen using the reflected light receiving position from the collimated light reflector arranged on the specimen. As described in the examples below, the coordinate plane is scanned by the collimator while measuring the intensity of the reflected light so that the collimated light transmitted to the specimen crosses any of the three or more collimated light reflectors. In addition, if scanning with a collimator is similarly performed from various directions and the reflected light intensity is measured, and the light receiving position when the reflected light intensity becomes equal to a predetermined threshold is obtained, typically The position coordinates of the collimated light reflector in the above coordinate system can be determined as the geometric center of the set of light receiving positions acquired in (1). By fitting the position coordinates of each collimated light reflector determined by performing such operations on each collimated light reflector to a rigid translational and rotational model as described above, The position and geometric orientation can be calculated.

  The collimating light reflector is composed of a high parallelism mirror and a covering member that is pressure-bonded to the high flatness mirror via a packing, from a slit provided at a predetermined position of the covering member to the high parallelism mirror. A reflector configured to reflect incident collimated light can be used.

  Further, the present invention provides a step of transmitting collimated light from the collimated light transmitting unit in the collimator, and a submillimeter wave beam receiving unit that is transmitted from the collimated light transmitting unit and includes a submillimeter wave beam receiving optical system. A step of receiving light reflected by any one of the three or more collimated light reflectors disposed at the position of the reflected light receiving unit in the collimator, and a predetermined coordinate system that defines an emission position of the collimated light, The step of determining the position where the reflected light is received by the position determining unit, and using the light receiving positions of the light reflected by the three or more collimated light reflectors respectively determined by the position determining unit, The position of the sub-millimeter wave beam receiving unit in the coordinate system and the geometric orientation of the sub-millimeter wave beam receiving unit with respect to the predetermined coordinate system, the position and geometric orientation calculating unit A submillimeter wave beam transmitted from the submillimeter wave beam transmitter and received by the submillimeter wave beam receiver using the submillimeter wave beam receiving optical system. Measuring the electromagnetic intensity of the beam by the submillimeter wave beam measuring unit, the electromagnetic intensity of the submillimeter wave beam measured by the submillimeter wave beam measuring unit, the emission position of the submillimeter wave beam in the coordinate system, the position and The electromagnetic intensity distribution in the coordinate system of the submillimeter wave beam transmitted from the submillimeter wave beam transmitter using the position and geometric orientation of the submillimeter wave beam receiver calculated by the geometric orientation calculator Determining the position of the submillimeter wave beam receiving unit. The electromagnetic wave in the above coordinate system of the submillimeter wave beam transmitted from the submillimeter wave beam transmitter is corrected after correction corresponding to the apparent change in the electromagnetic intensity distribution of the submillimeter wave beam that occurs depending on the geometric orientation. Provided is a submillimeter wave beam measurement method characterized by determining a dynamic intensity distribution.

  If the above method is used, it is possible to determine the electromagnetic intensity distribution of the submillimeter wave beam according to the same principle as the system of the present invention, while eliminating the apparent change due to misalignment. That is, collimated light is transmitted from the collimator to three or more reflectors arranged in the submillimeter wave beam receiving unit, the reflected light from the reflector is received to determine the light receiving position, and the submillimeter wave beam is determined from the light receiving position. After determining the misalignment between the transmitting system and the receiving optical system, and correcting the electromagnetic intensity distribution of the submillimeter wave beam by using the misalignment, the electromagnetic intensity from which apparent changes due to misalignment are eliminated The distribution can be determined.

  Alternatively, the method of the present invention is a method for determining the position of the specimen in a predetermined coordinate system and the geometric orientation of the specimen with respect to the predetermined coordinate system, wherein collimated light is transmitted from a collimated light transmitter in the collimator. And a reflected light receiving unit in the collimator, which is transmitted from the collimated light transmitting unit and reflected by any one of the three or more collimated light reflectors arranged at predetermined positions with respect to the specimen. , The step of determining the position where the reflected light is received in the predetermined coordinate system defining the emission position of the collimated light by the position determination unit, and 3 determined by the position determination unit, respectively. Using the light receiving position of the light reflected by the collimating light reflector, the position of the specimen in a predetermined coordinate system and the geometric orientation of the specimen with respect to the predetermined coordinate system are determined. It can be configured as a method comprising the steps of calculating the position and the geometrical orientation calculation unit.

  If such a method is used, the position and geometric orientation of the specimen relative to a predetermined coordinate system can be measured with high accuracy by a non-contact method.

  The above method determines a position in a predetermined coordinate system and a geometric orientation with respect to a predetermined coordinate system for a measurement target wavelength band light beam receiving unit including a measurement target wavelength band light beam receiving optical system as a specimen. It can be configured as a method for doing this. Such a method includes a step of transmitting a measurement target wavelength band light beam by the measurement target wavelength band light beam transmission unit, and a measurement target wavelength band light beam receiving optical system transmitted from the measurement target wavelength band light beam transmission unit. Measuring the electromagnetic intensity of the measurement target wavelength band light beam received by the measurement target wavelength band light beam receiver, and measuring the measurement target wavelength band light beam measurement section. The measurement target wavelength band light beam receiving unit calculated by the electromagnetic intensity of the measurement target wavelength band light beam, the emission position of the measurement target wavelength band light beam in the coordinate system, and the position and geometric orientation calculation unit. Using the position and geometric orientation, the intensity distribution of the electromagnetic intensity distribution in the coordinate system of the measurement target wavelength band light beam transmitted from the measurement target wavelength band light beam transmitter It can further include the steps of determining the tough. By using such a method, correction corresponding to the apparent change in the measurement target wavelength band light beam electromagnetic intensity distribution, which occurs depending on the position and geometric orientation of the measurement target wavelength band light beam receiver, is performed. In addition, the electromagnetic intensity distribution in the coordinate system of the measurement target wavelength band light beam transmitted from the measurement target wavelength band light beam transmission unit can be determined.

  The method of the present invention can be configured as a method for determining the electromagnetic intensity distribution of a beam belonging to an arbitrary wavelength range to be measured without being limited to the submillimeter wave band.

  On the other hand, the step of transmitting the measurement target wavelength band light beam may be a step of transmitting a submillimeter wave beam by a submillimeter wave beam transmitting unit, and the measurement target wavelength band light beam receiving unit is configured to receive a submillimeter wave beam. It may be a submillimeter wave beam receiver provided with an optical system.

  The method of the invention is particularly suitable for determining the electromagnetic intensity distribution of a submillimeter wave beam that is affected even by small errors associated with the setup that cannot be removed by maintenance prior to measurement.

  In the method of the present invention, the step of transmitting the collimated light and the step of receiving the reflected light include moving the collimator within the coordinate system using the moving mechanism unit and the distance between the collimator and the specimen. The collimated light is transmitted from any output position in the coordinate system to the collimated light reflector at an arbitrary distance from the autocollimator, and the reflected light is received in the arbitrary light reception in the coordinate system. Each can be configured to receive light at a location. Further, the step of determining the received position is configured such that the position determination unit determines the position at which the reflected light is received based on information relating to the movement of the collimator in the coordinate system by the movement mechanism unit. The step of transmitting the measurement target wavelength region light beam can be performed by moving the measurement target wavelength region light beam transmission unit within the coordinate system using the moving mechanism unit and the measurement target wavelength region light beam transmission unit and the specimen. Is configured to transmit the measurement target wavelength region light beam from the arbitrary emission position in the coordinate system to the specimen at an arbitrary distance from the measurement target wavelength region light beam transmission unit. The step of determining the electromagnetic intensity distribution of the measurement target wavelength band light beam in the coordinate system by the intensity distribution determination section is performed by the movement mechanism section. Based on the information on the movement in the coordinate system, the position determination unit determines the emission position of the measurement target wavelength band light beam in the coordinate system, and the electromagnetic intensity distribution is determined using the determined emission position. Can do.

  Similar to the system of the present invention, in the method of the present invention, for example, first to third direction shaft portions that extend in the first to third directions and are slidably attached to each other, and the first direction shaft portions. By using a moving mechanism unit comprising a base on which a collimator or a beam transmission unit, which is slidably attached, can be installed, the shaft unit and the base are slid relative to each other, so that collimated light or A light beam to be measured can be transmitted. In addition, by storing the amount of movement of the collimator or the measurement target wavelength range light beam transmission unit in each direction by the movement mechanism unit, the collimator position when receiving the reflected light, the beam transmission unit when transmitting the measurement target wavelength range light beam And the reflected light receiving position and beam emitting position can be determined.

  The method of the present invention further uses the electromagnetic intensity distribution in the coordinate system of the measurement target wavelength band light beam determined by the intensity distribution determination unit, and the beam center position of the measurement target wavelength band beam in the coordinate system, and The step of determining the beam width by the first statistical analysis means, and the respective electromagnetic intensities determined by the intensity distribution determining unit while changing the distance between the light beam transmitting unit to be measured and the specimen by the moving mechanism unit Determining the propagation vector direction and beam offset of the measurement target wavelength band light beam by the second statistical analysis means using each beam center position determined by the first statistical analysis means for the distribution. It may be a thing.

  Similar to the system of the present invention, the method of the present invention can also perform statistical analysis on the electromagnetic intensity distribution of the beam obtained by measurement to determine various beam parameters.

  The method of the present invention may further include the step of measuring the intensity of the received reflected light by the reflected light receiving unit. Further, the step of calculating the position of the specimen in the predetermined coordinate system and the geometric orientation of the specimen with respect to the predetermined coordinate system is calculated by the position and geometric orientation calculation unit with an intensity equal to a predetermined threshold value. Determining the position of each of the three or more collimated light reflectors in the coordinate system based on the two or more light receiving positions determined by the position determining unit as the position where the reflected light is received; Using each position of the three or more collimated light reflectors, a stage comprising the step of calculating the position of the specimen in a predetermined coordinate system and the geometric orientation of the specimen relative to the predetermined coordinate system may be used. it can.

  In the above configuration, the position of the corresponding collimated light reflector in the predetermined coordinate system is specified from the set of positions where the reflected light having the intensity equal to the predetermined threshold is received. This corresponds to an embodiment of the method of the present invention for calculating the position and geometric orientation of the specimen from the position of the collimating reflector.

  The present invention further includes a step of transmitting collimated light from the collimated light transmitting unit in the collimator, and a predetermined value for each of the submillimeter wave beam receiving units that are transmitted from the collimated light transmitting unit and include the submillimeter wave beam receiving optical system. The light reflected by any one of the three or more collimated light reflectors arranged at the position is received by the reflected light receiving unit of the collimator, and reflected in a predetermined coordinate system that defines the emission position of the collimated light. Determining the position at which the received light has been received by the position determining unit, and using the light receiving positions of the light reflected by the three or more collimated light reflectors respectively determined by the position determining unit, The position of the submillimeter wave beam receiving unit in the coordinate system and the geometric orientation of the submillimeter wave beam receiving unit with respect to the predetermined coordinate system are determined by the position and the geometric arrangement. A step of calculating by the calculating unit is performed with respect to a predetermined distance between the collimator and the submillimeter wave beam receiving unit selected by moving the collimator using the moving mechanism unit, and the predetermined distance The submillimeter wave beam is transmitted by the submillimeter wave beam transmitting section from the submillimeter wave beam emitting position having a known displacement with respect to the collimated light emitting position in the collimated light transmitting section, and the submillimeter wave beam transmission. Measuring the electromagnetic intensity of the submillimeter wave beam transmitted by the submillimeter wave beam receiving optical system using the submillimeter wave beam receiving optical system by the submillimeter wave beam measuring section. The sub-millimeter wave beam transmitter is moved in the coordinate system using the The electromagnetic intensity distribution in the coordinate system of the submillimeter wave beam transmitted from the submillimeter wave beam transmitter is defined by the electromagnetic intensity of the submillimeter wave beam measured by the submillimeter wave beam measuring section and the submillimeter wave beam in the coordinate system. The output position of each wave beam and the position and geometric orientation of the submillimeter wave beam reception unit calculated by the position and geometric orientation calculation unit are determined by the intensity distribution determination unit, and the collimator Determining the three-dimensional distribution of the electromagnetic intensity of the submillimeter wave transmitted from the submillimeter wave beam transmitting unit by changing each distance and the electromagnetic intensity distribution while changing the distance from the submillimeter wave beam receiving unit. A submillimeter wave beam measuring method is provided.

  By re-determining the misalignment each time the distance between the transmission system and the reception optical system is changed, the influence of the misalignment can be more strictly removed from the electromagnetic intensity distribution obtained by the measurement. In addition, if the submillimeter wave beam is measured while changing the distance between the transmission system and the reception optical system and the electromagnetic intensity distribution is determined, the submillimeter wave is obtained as a set of intensity distributions obtained for each distance. A three-dimensional distribution of the electromagnetic intensity of the beam can be obtained.

  Using the system and method of the present invention, when performing near-field measurement of a high-frequency beam such as a submillimeter wave band, a slight misalignment between the transmission system and the reception optical system that cannot be removed by maintenance before measurement is performed. It is possible to obtain a more precise measurement result by eliminating the influence on the measurement result. As a result, parameters such as the beam width and propagation vector direction of the submillimeter wave can be determined with unprecedented high accuracy (with respect to the beam width, an error range of about 50 μm).

  Also, by measuring the beam while changing the distance between the transmission system and the reception optical system, and obtaining the change of the submillimeter wave beam width with respect to the distance, the design parameters of the optical system can be determined, and the change of the beam center with the distance By obtaining the (propagation vector direction), it is possible to verify the alignment between the transmission system and the reception optical system by submillimeter waves.

  Furthermore, the alignment measurement between the transmission system and the reception optical system according to the present invention can be performed without touching the equipment and components that constitute each system, and mechanical damage to them can be avoided.

It is a whole block diagram at the time of alignment measurement of the submillimeter wave beam measurement system which is one embodiment of the present invention. It is a whole block diagram at the time of submillimeter wave beam measurement of a submillimeter wave beam measurement system which is one embodiment of the present invention. It is the figure which depicted the state where the collimator used for the submillimeter wave beam measurement system of the present invention was attached to the base. It is a figure showing the more detailed structure of the submillimeter wave beam measurement system which is one Embodiment of this invention. It is a figure showing the more detailed structure of a collimated light reflector. FIG. 5 is a diagram illustrating a specimen and a collimated light reflector when the submillimeter wave beam measurement system in FIG. 4 is viewed from the z direction in FIGS. 1 and 2. It is a figure for demonstrating the apparent change of the beam which originates in the misalignment between a submillimeter wave beam transmission system and a submillimeter wave beam receiving optical system. It is a graph showing the result of having measured the reflected light intensity, scanning the plane in a predetermined coordinate system with a collimator so that collimator light may cross a collimated light reflector from right or left.

  With reference to the drawings, the submillimeter wave beam measurement system, the measurement method, and the measurement data obtained thereby are used to determine the intensity distribution of the submillimeter wave beam, and various beam parameters are determined by statistical analysis. A method for this will be described. However, the configuration of the system and method according to the present invention is not limited to a specific specific configuration shown in each drawing, and can be appropriately changed within the scope of the present invention. As described above, the system of the present invention is not limited to the submillimeter wave band, and can be used to measure an arbitrary measurement target wavelength band light beam and perform intensity distribution determination and statistical analysis.

Configuration of Submillimeter Wave Beam Measuring System 1 FIGS. 1 and 2 are overall configuration diagrams of a submillimeter wave beam measuring system 1 according to an embodiment of the present invention. However, in FIG. 1, elements used for alignment measurement and misalignment determination are shown, and in FIG. 2, elements used for submillimeter wave beam measurement are shown.

  That is, the local oscillator 20, the mixer 21, the amplifier 22, the submillimeter wave beam measuring unit 23, the intensity distribution determining unit 24, and the statistical analysis unit 25 of FIG. 2 are not shown in FIG. 1 because they are used only when measuring the submillimeter wave beam. . These elements may be incorporated into the system when the alignment measurement and the misalignment determination are completed and the submillimeter wave beam is measured, or may be incorporated from the time of the alignment measurement. The submillimeter wave beam receiving optical system 11 including a mirror and an electromagnetic horn for converging and reflecting the submillimeter wave beam transmitted from the submillimeter wave transmitter 26 and guiding it to the mixer 21 is also used only when measuring the submillimeter wave beam. Although it is an element used, in order to measure a submillimeter wave beam in a state in which the measured alignment is strictly maintained, it is desirable to install it in the specimen 10 in advance. The specimen 10 referred to here is a metal housing base made up of the submillimeter wave beam receiving optical system housing portion 8 and the direction defining plate 9, and the submillimeter wave beam receiving optical system 11 is housed in the housing portion 8. Further, the collimated light reflectors 12, 13, and 14 are arranged at predetermined positions on the direction defining plate 9 to constitute a submillimeter wave beam receiving unit. In this embodiment, the orientation of the specimen 10 is defined by the direction of the direction defining plate 9.

  As will be described later, while the collimator 2 is moved by the moving mechanism unit 7 during alignment measurement, collimated light is transmitted to the collimated light reflectors 12, 13, and 14 on the direction defining plate 9 of the specimen 10. At the time of submillimeter wave beam measurement, the submillimeter wave beam receiving optical system 11 installed in the submillimeter wave beam receiving optical system housing section 8 of the specimen 10 is moved while moving the submillimeter wave transmitter 26 by the moving mechanism section 7. The submillimeter wave beam is transmitted through the submillimeter wave beam inlet 15. In this embodiment, in order to perform such an operation, the collimator 2 is installed on the transmitter base 3 during alignment measurement, while the submillimeter wave beam transmitter 26 is installed after removing the collimator 2 during submillimeter wave beam measurement.

  As already described, since it is possible to emit collimated light and a submillimeter wave beam from an arbitrary position using a large apparatus, transmission is performed while the collimator 2 and the submillimeter wave beam transmitter 26 are moved. Is not required.

(1) Configuration at the time of alignment measurement First, the configuration of the submillimeter wave beam measurement system 1 at the time of alignment measurement will be described with reference to FIG. In this embodiment, the alignment is fixed in the specimen 10 with respect to the submillimeter wave beam transmission system 28 (FIG. 2) composed of the submillimeter wave beam transmitter 26, the transmitter base 3, and the moving mechanism unit 7. The relative position and inclination of the sub-millimeter wave beam receiving optical system 11 will be referred to. Since the submillimeter wave beam receiving optical system 11 is fixed with respect to the specimen 10, the alignment is determined by determining the relative position and inclination of the specimen 10 with respect to the transmission system 28.

  In FIG. 1, the collimator 2 includes a collimated light transmission unit including an appropriate light source and a collimator lens for transmitting collimated light (parallel light rays) to the collimated light reflectors 12 to 14, and the collimated light reflectors 12 to 12. And a reflected light receiving unit made up of a light receiving element such as a CCD for receiving reflected light from 14. Here, the reflected light receiving unit measures the received light intensity at a predetermined position within the light receiving surface by measuring the amount of charge generated when the reflected light is imaged at the predetermined position within the light receiving surface of the light receiving unit. It is assumed that an arbitrary processing circuit (not shown) is provided. Alternatively, the processing circuit may be configured as a circuit for measuring the received light intensity at each light receiving position by measuring the received light intensity at each position in the light receiving surface.

  FIG. 3 shows the state in which the collimator 2 is attached to the transmitter base 3 in more detail. In addition to the collimator 2, the transmitter base 3 includes a polarization angle rotation mechanism 29 and a distance fine adjustment stage 30. These are elements used when measuring the submillimeter wave beam with the collimator 2 removed and the submillimeter wave beam transmitter 26 (FIG. 2) attached, and are not used when measuring the alignment.

  At the time of alignment measurement, the collimator 2 is fixed to the transmitter base 3. As will be described later, collimated light can be transmitted from an arbitrary position by moving the transmitter base 3 in the x, y, and z directions in FIG.

  The moving mechanism unit 7 includes a first direction shaft portion 4 extending in the first direction (x direction), a second direction shaft portion 5 extending in the second direction (y direction), and a third direction (z direction). And a third direction shaft portion 6 extending in the direction. The transmitter base 3 is attached to slide in the x direction with respect to the first direction shaft portion 4, and one end of the first direction shaft portion 4 is attached to slide in the y direction with respect to the second direction shaft portion 5. The second direction shaft portion 5 is attached to slide in the z direction with respect to the third direction shaft portion 6. The third direction shaft portion 6 is fixed to the support base 16. FIG. 4 shows an example of such a moving mechanism unit 7 manufactured by the present inventor. As shown in FIG. 4, it is not essential to use the moving mechanism portion 7 in which three orthogonal shaft portions are slidably coupled. Any other mechanism may be used as a mechanism for moving the collimator 2 and the submillimeter wave beam transmitter 26.

  Here, the sliding operation of the transmitter base 3 with respect to the first direction shaft portion 4, the sliding operation of the first direction shaft portion 4 with respect to the second direction shaft portion 5, and the third direction shaft portion 6 of the second direction shaft portion 5. The sliding operation is performed under the control of the moving mechanism control unit 17. The movement mechanism control unit 17 is a controller that generates and transmits a signal for instructing the movement mechanism unit 7 to perform each of the above sliding operations for an arbitrary length. Further, information on the route to be followed by the transmitter base 3 is stored in advance in a storage device of an appropriate computer (not shown), the computer is connected to the moving mechanism control unit 17, and according to the route. The moving mechanism control unit 17 can also be controlled by the computer so that the moving mechanism control unit 17 sequentially generates a slide operation command signal for moving the transmitter base 3.

  The scanner 18 receives information on the slide operation performed in the transmitter base 3 and the shafts 4 to 6 from the moving mechanism control unit 17 and uses the information on the slide operation to present the current state of the transmitter base 3. A device for determining the position. When the position of a predetermined reference point with respect to the transmitter base 3 when the power of the moving mechanism unit 7 is turned on is the origin, the transmitter base 3 slides in the positive x direction with respect to the first direction shaft portion 4. The length of the first direction shaft portion 4 slid in the positive y direction with respect to the second direction shaft portion 5 is ly, and the second direction shaft portion 5 is relative to the third direction shaft portion 6. Thus, the current coordinate of the reference point can be determined as (lx, ly, lz), where lz is the length slid in the positive z direction. The relative coordinates between the coordinates of the reference point with respect to the transmitter base 3 and the coordinates of the predetermined position at which the received light intensity is measured within the light receiving surface of the collimator 2 are not changed by the movement of the transmitter base 3. (The collimator 2 is fixed with respect to the transmitter base 3). If the current coordinates (lx, ly, lz) of the reference point are determined by the scanner 18, the reflected light receiving position at that time is determined. Will be. The scanner 18 as the position determination unit is typically configured as a computer that operates according to an information processing program.

  In the alignment measurement in the present embodiment, the transmitter base 3 is slid with respect to the first direction shaft portion 4 while the position of the collimator 2 in the z direction is fixed, and the first direction shaft portion 4 is moved to the second direction. It is performed by transmitting collimated light to the collimated light reflectors 12, 13, and 14 while moving the collimator 2 in the x and y directions by sliding with respect to the direction shaft portion 5. Therefore, a coordinate system that defines a position related to the x direction and the y direction among the x, y, and z directions defined by the shaft portions 4 to 6 in the first direction to the third direction is hereinafter referred to as “predetermined coordinate system”. " In the present embodiment, the alignment is determined by determining the position of the specimen 10 in the predetermined coordinate system thus defined and the geometric orientation of the specimen 10 with respect to the predetermined coordinate system.

  The position and geometric orientation calculation unit 19 receives an input of the current reflected light receiving position from the scanner 18 and also receives an input of the current reflected light intensity measured in the collimator 2 from the collimator 2. The apparatus is used to calculate the position of the specimen 10 in the predetermined coordinate system and the geometric orientation of the specimen 10 with respect to the predetermined coordinate system. Note that the current coordinates (lx, ly, lz) of the reference point of the transmitter base 3 instead of the reflected light receiving position are input from the scanner 18, and the position and geometric orientation are calculated based on the current coordinates of the reference point. The unit 19 itself may determine the current reflected light receiving position. Alternatively, the position and geometric orientation calculation unit 19 receives a set of received light intensity at each position in the light receiving surface from the collimator 2, and receives the received light intensity set and the reference point input from the scanner 18. The received light intensity distribution corresponding to the current position of the collimator 2 in the predetermined coordinate system may be determined using the current coordinates (lx, ly, lz). In one example, the position and geometric orientation calculation unit 19 has a maximum reflected light intensity received by the collimator 2 when transmitting the collimated light while moving in the predetermined coordinate system by the moving mechanism unit 7. The position of each of the collimated light reflectors 12 to 14 in the predetermined coordinate system is determined as the reflected light receiving position, and the determined position is fitted to a translational / rotational model of the rigid body by fitting the determined position to a rigid model. The position and orientation are calculated. In this case, it is sufficient for the position and geometric orientation calculation unit 19 to receive only the light receiving position corresponding to the maximum value of the reflected light intensity from the scanner 18, and it is necessary to receive the reflected light intensity input from the collimator 2. There is no.

  Furthermore, it is not essential to determine the positions of the collimated light reflectors 12 to 14 as the light receiving position coordinates when the light receiving intensity becomes maximum. For example, the collimator is moved within the predetermined coordinate system while measuring the intensity of the reflected light so that the collimated light transmitted to the specimen crosses one of the collimated light reflectors. If the set of light receiving positions when the intensity of the reflected light is equal to a predetermined threshold is obtained after measuring the reflected light intensity while crossing the line, typically the geometry of the light receiving positions thus obtained is obtained. As a geometric center, the position of the collimated light reflector in the coordinate system can be determined. When the collimator 2 directly receives the laser beam that is completely specularly reflected from the collimated light reflectors 12 to 14, the received light intensity is saturated in the reflected light receiving part of the collimator, and the light reception corresponding to the maximum value of the received light intensity. The position coordinates may not be determined accurately. In such a case, it is desirable to determine the position of each collimated light reflector from the set of light receiving positions corresponding to the predetermined threshold as described above. It is possible to calculate the position and orientation of the specimen 10 by fitting the positions of the collimated light reflectors 12 to 14 thus determined to a rigid translational and rotational model.

  FIG. 5 shows a slit collimated light reflector (an example of collimated light reflectors 12-14) that is particularly suitable for embodiments that determine the position of the reflector as the geometric center as described above. The collimated light reflector with slits is composed of a covering member 35, a high parallelism aluminum vapor deposition mirror 32, most of which is covered by the covering member 35, and a Teflon (registered trademark) packing (not shown) between them. ing. The covering member 35 has a hole (circular slit 31) smaller than the diameter of the mirror, and collimated light is incident on the mirror 32 through the circular slit 31. Since the collimated light reflector with slit is aligned with the specimen 10 by the two positioning pins respectively inserted into the two positioning pin holes 33, the center of the circular slit 31 is the collimating light reflector. It becomes the reference of the position. The covering member 35 is screwed to the mirror 32 through the mounting screw hole 34, and the mirror 32 is pressed from the aluminum vapor deposition surface (mirror surface) side through the packing, so that the reference surface (back surface) of the mirror 32 is the specimen. 10 is representative of the mechanical orientation of the specimen 10. For alignment measurement, it is necessary to obtain information on the relative position shift and rotation of the specimen 10 with respect to the predetermined coordinate system (rotation information about the x-axis and y-axis). Three or more light reflectors are attached to the specimen 10. 6 shows the specimen 10 to which the slit collimated light reflectors 12 to 14 shown in FIG. 5 are attached in the submillimeter wave beam measurement system 1 manufactured by the present inventor as viewed from the z direction in FIG. (However, the submillimeter wave beam receiving optical system 11 is not shown because it is accommodated in the specimen 10). The alignment measurement is performed by transmitting collimated light to the collimated light reflectors 12 to 14 while moving the collimator 2 in the xy plane and measuring the light receiving position of the reflected light. In the following, it is assumed that the collimated light reflectors 12 to 14 are the collimated light reflectors with slits in FIG.

(2) Configuration at the time of submillimeter wave beam measurement Next, the configuration of the submillimeter wave beam measurement system 1 at the time of submillimeter wave beam measurement will be described with reference to FIG.

  Unlike the configuration in FIG. 1, in the system in FIG. 2, a submillimeter wave beam transmitter 26 is installed in the transmitter base 3. An example of the submillimeter wave beam transmitter 26 used in the present embodiment is a frequency multiplier that connects an amplifier to a Gunn diode capable of generating a high frequency exceeding 100 GHz and further outputs a frequency signal that is twice the input frequency. And a frequency multiplier that outputs a frequency signal that is three times the input frequency is connected to output a submillimeter wave beam of an arbitrary frequency in the 640 GHz band. Correspondingly, the above-mentioned local oscillator 20 is configured to output a local oscillation signal having a predetermined frequency in the 640 GHz band. The submillimeter wave beam measurement unit 23 measures the intensity of the intermediate frequency signal obtained by mixing the submillimeter wave beam and the local oscillation signal by the mixer 21, so that the submillimeter wave beam measurement unit 23 at an arbitrary frequency in the 640 GHz band corresponding to the submillimeter wave beam. Measure the beam intensity (power intensity, electric field intensity, etc.). The submillimeter wave beam transmitted from the submillimeter wave beam transmitter 26 is incident on the submillimeter wave beam receiving optical system 11 through the submillimeter wave beam entrance 15 provided in the specimen 10.

  At the time of measuring the submillimeter wave beam, the submillimeter wave beam is transmitted while moving the transmitter base 3 provided with the submillimeter wave beam transmitter 26 within the predetermined coordinate system (xy plane) by the moving mechanism 7. Here, the relative coordinates between the beam emission position 27 (probe position) in the submillimeter wave beam transmitter 26 and the coordinates (lx, ly, lz) of the reference point with respect to the transmitter base 3 are the transmitters. Since it does not change depending on the movement of the base 3, if the current coordinates (lx, ly, lz) of the reference point are determined by the scanner 18, the current submillimeter wave beam emission position 27 is determined.

  In FIG. 2, the local oscillator 20 outputs a local oscillation (LO) signal for mixing with the received submillimeter wave beam. If the submillimeter wave beam is converted into an intermediate frequency (IF) signal having a low frequency by mixing, subsequent amplification and detection processing are facilitated.

  When the submillimeter wave beam measurement is performed at room temperature, the mixing can be performed by the Schottky barrier diode mixer 21. The Schottky barrier diode mixer 21 outputs an intermediate frequency signal having a frequency equal to the difference between the frequency of the submillimeter wave beam transmitted from the submillimeter wave beam transmitter 26 and the frequency of the local oscillation signal transmitted from the local oscillator 20. Is output. The intermediate frequency signal is amplified by one or more amplifiers 22 as necessary, and is measured by a spectrum analyzer as a submillimeter wave beam measurement unit 23 (the signal power as a received signal level, typically a submillimeter wave beam). However, depending on the specifications of the detector of the receiver such as a spectrum analyzer, the received signal level may be determined as the square root of such signal power). From the intensity of the submillimeter wave beam measured in this way, the two-dimensional distribution of the electromagnetic intensity of the submillimeter wave beam, and the submillimeter wave beam transmitting system 28 and the submillimeter wave beam receiving optical system 11 having such a two-dimensional distribution, The change according to the distance is determined. The electromagnetic intensity referred to here is typically the electric field intensity of the submillimeter wave beam theoretically determined from the signal power as described above, but the submillimeter is also theoretically determined from the signal power. The present invention can be configured to determine the distribution of the wave beam power as the electromagnetic intensity, or the sub-millimeter wave beam can be configured as a spectrum analyzer (or as a sub-millimeter wave beam measurement unit 23). The electromagnetic strength may be defined as another arbitrary amount that can be measured using another arbitrary measuring device.

  On the other hand, when the submillimeter wave beam measurement is performed at an extremely low temperature (liquid helium temperature), the above mixing can be performed by a superconductor SIS (Superconductor Insulator Superconductor) mixer 21. The superconducting SIS mixer 21 is a mixer formed by cooling an element formed by tunneling a superconductor layer, an insulator layer, and a superconductor layer, such as Nb / AlOx / Nb, to a superconducting state. . In the measurement at a cryogenic temperature, the specimen 10, the superconducting mixer 21, and the amplifier 22 are maintained at a liquid helium temperature in a cryostat (not shown). In the following, the configuration and operation of the submillimeter wave beam measurement system 1 will be described on the assumption that a Schottky barrier diode mixer is used. However, when measurement is performed at a cryogenic temperature using a superconducting SIS mixer, and under any other conditions Even when measurement is performed using an arbitrary mixer, the present invention can be implemented based on the same principle.

  The intensity distribution determination unit 24 receives the input of the beam intensity measurement value from the submillimeter wave beam measurement unit 23 and further receives the input of the current submillimeter wave beam emission position 27 from the scanner 18. Using this information, the intensity distribution determination unit 24 inputs from the submillimeter wave beam measurement unit 23 as the electromagnetic intensity of the submillimeter wave beam at the position of the submillimeter wave beam entrance 15 as viewed from the current submillimeter wave beam emission position 27. Determine the electromagnetic intensity of the emitted beam. However, the position of the submillimeter wave beam entrance 15 is determined in advance by a separate measurement operation or the like and is input to the intensity distribution determination unit 24. In FIG. 2, the coordinates of the submillimeter wave beam exit position 27 and the submillimeter wave beam entrance 15 in the xy plane coincide with each other. However, in actual measurement, the submillimeter wave beam exit position 27 and the submillimeter wave beam entrance 15 in the xy plane near the submillimeter wave beam entrance 15 Measurement is performed while moving the wave beam emission position 27. In this way, by determining the beam intensity for various submillimeter wave beam emission positions 27, the electromagnetic intensity distribution of the submillimeter wave beam in the predetermined coordinate system is determined. Note that the current coordinates (lx, ly, lz) of the reference point are input from the scanner 18 instead of the submillimeter wave beam emission position 27, and the intensity distribution determination unit 24 itself performs the current emission based on the current coordinates of the reference point. The position 27 may be determined.

  In the present embodiment, the submillimeter wave beam receiving optical system 11 is fixed, and the submillimeter wave beam transmitter 26 is moved by the moving mechanism unit 7 to measure the beam, so that the submillimeter wave beam emission position 27 and the submillimeter wave beam incidence are measured. The electromagnetic intensity distribution of the beam with respect to the coordinates relative to the mouth 15 is determined. However, this is in consideration of the fact that it is preferable to measure with a cryostat fixed, particularly when a superconducting SIS mixer is used as the mixer 21, and the submillimeter wave beam is fixed while the submillimeter wave beam transmitter 26 is fixed. The measurement may be performed while moving the reception optical system 11.

  The intensity distribution determination unit 24 further receives from the position and geometric orientation calculation unit 19 the input of the position of the specimen 10 in the predetermined coordinate system and the geometric orientation of the specimen 10 with respect to the predetermined coordinate system. Based on these, the electromagnetic intensity distribution of the submillimeter wave beam is corrected. Thereby, the influence of misalignment is removed from the electromagnetic intensity distribution, and an electromagnetic intensity distribution when the alignment between the transmission system and the reception optical system is ideal can be obtained. A shift of the electromagnetic intensity distribution due to misalignment and a specific correction method for removing the influence will be described in detail later. The intensity distribution determination unit 24 is typically configured as a computer that operates according to an information processing program.

  The statistical analysis unit 25 receives an input of the electromagnetic intensity distribution from which the influence of the misalignment in the submillimeter wave beam is removed from the intensity distribution determination unit 24, and statistical analysis using a two-dimensional Gaussian distribution model or the like for these inputs. This is a device for obtaining beam parameters such as the beam center position and beam width in the coordinate system. The statistical analysis unit 25 further determines each beam center position when the distance between the submillimeter wave beam transmitter 26 and the specimen 10 is variously changed, and the propagation vector of the submillimeter wave beam based on the set of the center positions. A direction is determined, and a beam offset is determined based on the determined propagation vector direction. These specific methods will be described later in detail. The statistical analysis unit 25 is typically configured as a computer that operates by an information processing program.

  The polarization angle rotation mechanism 29 in FIG. 3 rotates the transmitter base 3 about the z-direction axis in FIG. 1 so that the submillimeter wave installed on the transmitter base 3 at the time of measuring the submillimeter wave beam. Rotate the beam transmitter 26 to adjust the polarization of the receiver to the polarization of the submillimeter wave beam to be transmitted (main polarization measurement), or to adjust the polarization of the receiver to the polarization orthogonal to the transmission polarization This is a mechanism for performing (cross polarization measurement).

  The distance fine adjustment stage 30 is a mechanism for moving the transmitter base 3 by λ / 4 in the z direction (λ is the wavelength of the submillimeter wave beam to be transmitted). In the measurement of the submillimeter wave beam, a standing wave is generated between the submillimeter wave beam transmitter 26 and the submillimeter wave beam receiving optical system 11. In order to suppress the influence of the standing wave on the electromagnetic intensity measurement result of the beam. It is effective to perform the same measurement after shifting the distance between the submillimeter wave beam transmitter 26 and the submillimeter wave beam receiving optical system 11 by λ / 4 and use the average value of the measured intensities.

  In the configuration described above, at least the function units of the movement mechanism control unit 17, the scanner 18, the position and geometric orientation calculation unit 19, the submillimeter wave beam measurement unit 23, the intensity distribution determination unit 24, and the statistical analysis unit 25 are executed. The function to be performed may be executed by a single computer operated by an appropriate information processing program. Or the function which they carry out can also be shared by arbitrary number of apparatuses. Furthermore, the operator himself / herself may perform at least a part of the functions executed by these functional units. For example, the position determination by the scanner 18 may be performed by an operator using information on a slide operation displayed on an appropriate display (not shown) connected to the moving mechanism unit 17, and the position and geometry are similarly determined. The fitting to the rigid body model by the automatic orientation calculation unit 19 may be performed by the operator himself according to theoretical formulas relating to translation and rotation of the rigid body model. Similarly, data input to and output from each function unit can be automatically performed by computer control via an appropriate wired / wireless line, or an operator himself can set each function unit. You may do it from the interface.

Operation of Submillimeter Wave Beam Measurement System 1 Next, a method for determining the electromagnetic intensity distribution of a submillimeter wave beam and calculating beam parameters using the submillimeter wave beam measurement system 1 will be described.

(1) Measurement of alignment and determination of misalignment First, the alignment between the submillimeter wave beam transmitting system 28 and the submillimeter wave beam receiving optical system 11 is measured, and the deviation from the actually measured alignment design value is measured. The operation for determining the misalignment will be described. In the following, misalignment is re-determined every time the distance between the transmission system and the reception optical system is changed in order to obtain a more precise measurement result. However, the present invention is implemented in this manner. Is not essential, and it is possible to consistently use alignments measured for a particular distance.

  The moving mechanism unit 7 moves the transmitter base 3 on the xy plane under the control of the moving mechanism control unit 17. At this time, since the second direction shaft portion 5 is fixed with respect to the third direction shaft portion 6, the movement of the collimator 2 is also limited to the xy direction. The collimator 2 continues to transmit collimated light toward the specimen 10 while moving in the xy direction, and at the same time, measures the received light intensity of the reflected light. The received light intensity of the reflected light that changes from time to time is output to the position and geometric orientation calculation unit 19. During this time, the scanner 18 determines the reflected light receiving position at each time point, and outputs it to the position and geometric orientation calculation unit 19. In addition, when the laser spot center position of the collimator 2 is not guaranteed by the product, it is necessary to separately configure the position and perform the instrumental error correction process.

  For each of the collimated light reflectors 12 to 14 with slits, the moving mechanism unit 7 scans the xy plane with the collimator 2 so that the collimated light crosses the reflector from various directions. FIG. 8 shows an example of the measurement result of the reflected light intensity when the collimator 2 is traversed from the left and right, that is, from both directions along the y-axis in FIG. Due to the symmetry of the shape of the circular slit 31, the change in reflected light intensity is substantially the same regardless of whether it is crossed from the left or right.

  The position and geometric orientation calculation unit 19 calculates the geometry of the reflected light receiving position coordinates when the reflected light intensity is at a predetermined level (for example, when “DET.LVL” in FIG. 8 is 120). As a geometric center, the position of the corresponding collimated light reflector with slits in the coordinate system is determined. Since the slit 31 is circular, when the collimated light crosses the reflector, even if it does not pass through the center of the mirror 32 of the reflector, the predetermined reflection obtained by various scans including up, down, left, and right The coordinates of the reflector can be obtained by taking the average of the light receiving positions corresponding to the light intensity.

  Through the above steps, the position and geometric orientation calculation unit 19 determines the positions of the collimated light reflectors 12 to 14 with slits in the predetermined coordinate system, and fits them into a rigid translational and rotational model. 10 positions and orientations are calculated.

Specifically, after considering the direction-defining plate 9 of the specimen 10 as a flat rigid plate,
(I) The direction of the direction defining plate 9 (normal direction of the surface of the direction defining plate 9) coincides with the negative direction of the z axis in FIG. 1, and a predetermined reference point in the direction defining plate 9 is in the xy plane. The xy of the collimated light reflectors 12 to 14 when the specimen 10 is placed in the xy plane so as to coincide with the origin (assuming that such an origin is previously defined as a fixed point before measurement). The coordinates (reference coordinates) are (x ₁ , y ₁ ), (x ₂ , y ₂ ), and (x ₃ , y ₃ ).
(Ii) The xy coordinates (measured coordinates) of the collimated light reflectors 12 to 14 determined based on the reflected light receiving position as described above are (x ₁ ′, y ₁ ′), (x ₂ ′, y ₂ ′). ), (X ₃ ', y ₃ ').
In this procedure, the reference coordinates and the actual measurement coordinates are determined for each reflector, and translational and rotational transformations connecting the coordinates are calculated by computer simulation or the like.

  That is, the reference coordinate and the actual measurement coordinate in each reflector are the translation of the direction defining plate 9 and the x axis and the y axis (with the predetermined reference point in the direction defining plate 9 fixed). Since the rotation is related by a combination of rotation, after the arbitrary translation and rotation about both coordinate axes are applied to the direction defining plate 9, the coordinates after movement starting from the reference coordinates are sequentially calculated by a computer. Thus, the position and orientation of the specimen 10 can be calculated (or a rotation matrix or the like) by finding a translation vector in which the calculated coordinate after movement matches the actual measurement coordinate and two rotation angles. The amount of translation and rotation may be derived analytically using).

The translation vector thus determined is defined as (ΔX ₀ , ΔY ₀ ), the rotation angle (pitch angle) around the x axis is Φ, and the rotation angle (yaw angle) around the y axis is Θ. As these sets, actual measurement values of the alignment in the present embodiment are given.

Here, in the present embodiment, the xy coordinates of the collimated light reflectors 12 to 14 coincide with the reference coordinates (x ₁ , y ₁ ), (x ₂ , y ₂ ), (x ₃ , y ₃ ). Assume that the arrangement of the specimen 10 is designed. In this case, the measured values of the translation vector, pitch angle, and yaw angle obtained by the above procedure all represent deviations from the design in the position and orientation of the specimen 10. That is, the misalignment is determined as a set of the translation vector (ΔX ₀ , ΔY ₀ ), the pitch angle Φ, and the yaw angle Θ.

  As described above, the apparent change in the beam intensity distribution caused by the influence of the misalignment can be removed by a correction calculation described later. However, in consideration of correction calculation errors and the like, it is desirable to adjust misalignment as much as possible by adjusting the arrangement of the optical system before measuring the submillimeter wave beam. That is, the beam measurement is continuously performed by repeating the procedure of finely adjusting the arrangement and inclination of the specimen 10 in accordance with the determined misalignment, measuring the alignment again, and checking the size of the misalignment. It is effective to adjust the measurement system 1 before.

(2) Measurement of submillimeter wave beam and determination of electromagnetic intensity distribution Next, while maintaining the misalignment finally determined through fine adjustment (the position and orientation in the specimen 10 after fine adjustment are unchanged) The electromagnetic intensity distribution of the submillimeter wave beam.

  First, after removing the collimator 2 from the transmitter base 3 and installing the submillimeter wave beam transmitter 26 instead, the moving mechanism unit 7 moves the transmitter base 3 on the xy plane under the control of the moving mechanism unit 17. Let At this time, since the second direction shaft portion 5 is fixed with respect to the third direction shaft portion 6, the movement of the submillimeter wave beam transmitter 26 is also limited to the xy direction. The submillimeter wave beam transmitter 26 continues to transmit the submillimeter wave beam toward the vicinity of the submillimeter wave beam entrance 15 while moving in the xy direction. Similar to the laser spot center of the collimator 2, the mechanical center of the transmission probe of the submillimeter wave transmitter 26 is also measured in advance with a three-dimensional measuring instrument, and instrumental error correction is performed by data processing as necessary.

  The submillimeter wave beam incident from the incident port 15 is converged and reflected by the action of each optical element constituting the submillimeter wave beam receiving optical system 11, and is then waveguide-connected from the electromagnetic horn in the receiving optical system 11. Input to the Schottky barrier diode mixer 21. The Schottky barrier diode mixer 21 mixes the submillimeter wave beam and the local oscillation signal input from the local oscillator 20 and outputs an intermediate frequency signal.

  The submillimeter wave beam measurement unit 23 determines the electromagnetic intensity of the submillimeter wave beam by measuring the intensity of the intermediate frequency signal, and outputs the electromagnetic intensity to the intensity distribution determination unit 24. At the same time, the current submillimeter wave beam emission position 27 is input from the scanner 18 to the intensity distribution determination unit 24. The submillimeter wave transmitter 26 scans the vicinity of the beam entrance 15 and measures the beam intensity at a sufficient number of measurement points.

  The intensity distribution determination unit 24 uses a measurement unit as a distribution of the electromagnetic intensity measurement values of the submillimeter wave beam transmitted from the emission position 27 with respect to the relative coordinates between the submillimeter wave beam emission position 27 and the submillimeter wave incident port 15. 23 and the measurement data input from the scanner 18 are used to determine the electromagnetic intensity distribution of the submillimeter wave beam.

(3) Correction of Electromagnetic Intensity Distribution Further, the intensity distribution determining unit 24 receives information on the position and geometric orientation of the specimen 10 determined by the position and geometric orientation calculating unit 19 and receives them. Based on the above, the electromagnetic intensity distribution of the submillimeter wave beam is corrected. That is, after an apparent change in the electromagnetic intensity distribution caused by the misalignment is determined, correction that cancels this change is performed on the electromagnetic intensity distribution obtained from the measurement data.

In the present embodiment, the information on the position and the geometric orientation is input as a set of a translation vector (ΔX ₀ , ΔY ₀ ), a pitch angle Φ, and a yaw angle Θ, which is a quantity representing misalignment. . This misalignment causes an apparent change in the beam as described below.

FIG. 7 is a diagram for explaining an apparent change in the beam caused by misalignment between the submillimeter wave beam transmission system 28 and the submillimeter wave beam reception optical system 11. In FIG. 7, the transmission side coordinate system 36 is a coordinate system defined by coordinate axes in the x, y, and z directions in which the first to third direction axis portions 4 to 6 extend, and the reception side coordinate system 37 is a direction definition. This is a coordinate system defined by an x _zn axis and a y _zn axis that define a plane along the surface of the plate 9 and an axis in the normal direction of the surface (a chain line in FIG. 7) (n = The case of 1 and 2 is shown as a representative). Here, n is an integer index representing various distances between the submillimeter wave transmission system 28 and the reception optical system 11 that are changed by sliding the second direction shaft portion 5 with respect to the third direction shaft portion 6. (In FIG. 7, since the transmission side coordinate system 36 is drawn in a fixed manner, the reception side coordinate system 37 moves in accordance with the change in distance).

ここで、ΔＸ₀，ΔＹ₀，Φ，Θはいずれも微小量であるとし、上記（１），（２）式においてこれらの２次以上の量は無視した。このような扱いは説明を単純化する目的のためだけになされるものであって、当然ながら、本発明において高次の微小量を無視することは必須の要件ではない。座標系の並進、回転変換に関する理論式を用いれば、更に厳密にシフト量を決定してビームパターンを分析することが可能である。当業者であれば、本明細書の開示に従い、適宜そのような態様で本発明を実施することができる。 The reception side coordinate system 37 is shifted by (ΔX ₀ , ΔY ₀ ) in the (x, y) direction with respect to the transmission side coordinate system 36, and the x _zn axis and the y _zn axis are the x axis and the y axis. Are inclined by a pitch angle Φ and a yaw angle Θ. When such a misalignment exists, if a submillimeter wave beam transmitted from (x, y) = (Δx ₀ , Δy ₀ ) in the transmission side coordinate system 36 is observed in the reception side coordinate system 37, z = At a position separated by z _n , the beam incident position is shifted by the following F _xerr (z _n ) and F _yerr (z _n ) in the x _zn axis and y _zn axis directions, respectively.

Here, it is assumed that ΔX ₀ , ΔY ₀ , Φ, and Θ are all minute amounts, and these secondary and higher amounts are ignored in the above formulas (1) and (2). Such treatment is performed only for the purpose of simplifying the explanation, and it is a matter of course that ignoring high-order minute amounts is not an essential requirement in the present invention. By using a theoretical formula relating to translation and rotation conversion of the coordinate system, it is possible to determine the shift amount more strictly and analyze the beam pattern. A person skilled in the art can implement the present invention in such a mode as appropriate according to the disclosure of the present specification.

上記（３）式を用いて、実際に測定される｜Ｅ’_zn（ｘ_n，ｙ_n）｜を変換することにより、ミスアラインメントの影響が排されたビーム強度分布が得られる。 It is a beam incident position measured in the x _n y _n plane of the receiving side coordinate system 37 (x _n (z _n ), y _n (z _n )) = (Δx (z ₁ ), Δy (z ₁ )) , (Δx (z ₂ ), Δy (z ₂ )) are incident positions after shifting by an amount given by the above equations (1) and (2) due to misalignment. That is, the beam incident position when there is no misalignment can be expressed as (Δx _n (z _n ) −F _xerr (z _n ), Δy _n (z _n ) −F _yerr (z _n )). . Therefore, in the case of that there is no misalignment, (as an example, the electric field intensity distribution.) Beam intensity distribution in an ideal x _n y _n plane _{| E zn (x n, y} n) | and Miss If the intensity distribution of the actually measured submillimeter wave beam shifted by the influence of the alignment is represented by | E ′ _zn (x _n , y _n ) |, the two are associated by the following equations.

By converting | E ′ _zn (x _n , y _n ) | actually measured using the above equation (3), a beam intensity distribution that eliminates the effects of misalignment can be obtained.

を用いて、最小自乗法によるフィッティングを行う。

(4) Determination of beam center position and beam width For a specific z _n = z _i , a beam intensity pattern | E _zi (x _i , y _i ) | If so, by fitting | E _zi (x _i , y _i ) | ² to an appropriate statistical model function, such as a quadratic Gaussian distribution model, the beam center at a distance z _i from the submillimeter wave beam transmitter 26 The position and beam width can be determined. In this embodiment, the following two-dimensional Gaussian distribution function

Is used for fitting by the method of least squares.

ｙ軸方向のピーク位置（ビーム中心位置）、

ｘ軸方向のビーム幅ω_x（ｚ_i）、
ｙ軸方向のビーム幅ω_y（ｚ_i）、
ガウス分布円の傾斜度ρ（ｚ_i）
を未知のパラメータとして、補正後のビーム強度パターンの自乗値｜Ｅ_zi（ｘ_i，ｙ_i）｜²と上記（４）式により計算される２次元ガウス分布関数

との自乗誤差が最小となるようなパラメータの組を、Ｌｅｖｅｎｂｅｒｇ−Ｍａｒｑｕａｒｄｔ法などによって決定する。 Specifically, in the above formula (4),
Bias value a,
Amplitude b,
peak position in the x-axis direction (beam center position),

peak position in the y-axis direction (beam center position),

beam width ω _x (z _i ) in the x-axis direction,
beam width ω _y (z _i ) in the y-axis direction,
Degree of inclination of Gaussian circle ρ (z _i )
Is the unknown parameter, the square value of the corrected beam intensity pattern | E _zi (x _i , y _i ) | ² and the two-dimensional Gaussian distribution function calculated by the above equation (4)

Is determined by the Levenberg-Marquardt method or the like.

(5) Beam propagation vector direction and offset determination The above operations (1) to (4) are repeated while changing the distance z _i between the submillimeter wave beam transmission system 28 and the submillimeter wave beam reception optical system 11. As a result, a three-dimensional distribution of submillimeter wave beam electromagnetic intensity from which the influence of misalignment is eliminated is obtained, and beam center positions for various distances z _i are obtained. If the beam center position thus obtained is fitted to a linear function of the distance z _{i by} the least square method, the propagation vector direction and offset of the beam can be determined without the influence of misalignment. it can. In this embodiment, fitting by the least square method is performed using the following linear function.

と、の自乗誤差が最小となるようなパラメータの組が、以下の（７）〜（１０）式により与えられる。

ただし、ｚ₁〜ｚ_NというＮ通りの距離について、それぞれミスアラインメントの決定、サブミリ波ビーム強度分布の測定、及び２次元ガウス分布関数によるフィッティングを行い、ビーム中心のｘ座標Δｘ（ｚ₁）〜Δｘ（ｚ_N）、及びｙ座標Δｙ（ｚ₁）〜Δｙ（ｚ_N）が決定されているものとする。 Specifically, in the above formulas (5) and (6),
The rotation angle θ around the y-axis of the beam propagation vector,
Rotation angle φ around the x-axis of the beam propagation vector,
X-coordinate Δx _o of offset as beam center at distance z _i = 0
Y coordinate Δy _o of the offset as the beam center at distance z _i = 0
Is an unknown parameter, beam center position coordinates Δx (z _i ), Δy (z _i ) as a function of z _i obtained by fitting using the above equation (4) for each distance z _i , and the above As a function of z _i calculated by equations (5) and (6)

A set of parameters that minimizes the square error is given by the following equations (7) to (10).

However, for N distances z _{1 to} z _N , misalignment determination, submillimeter wave beam intensity distribution measurement, and fitting with a two-dimensional Gaussian distribution function are performed, and the x coordinate Δx (z ₁ ) ˜ It is assumed that Δx (z _N ) and y coordinates Δy (z ₁ ) to Δy (z _N ) have been determined.

  The present invention can be used in the field of astronomical and space observation using the submillimeter wave and the earth atmosphere environment field. Since the influence on the measurement result due to the error associated with the setup of the beam measurement test can be removed by post-measurement data processing, it is strictly possible in the submillimeter wave band, which was previously impossible due to the limitations of manufacturing and assembly technology. Beam measurement can be performed.

DESCRIPTION OF SYMBOLS 1 Submillimeter wave beam measurement system 2 Collimator 3 Transmitter base 4 1st direction shaft part 5 2nd direction shaft part 6 3rd direction shaft part 7 Movement mechanism part 8 Submillimeter wave beam receiving optical system accommodating part 9 Directional direction plate 10 Specimen 11 Submillimeter wave beam receiving optical system 12 Collimated light reflector 13 Collimated light reflector 14 Collimated light reflector 15 Submillimeter wave beam entrance 16 Support base 17 Moving mechanism controller 18 Scanner 19 Position and geometric orientation calculator 20 Local Oscillator 21 Mixer (Schottky barrier diode mixer or superconducting SIS mixer)
22 Amplifier 23 Submillimeter wave beam measurement unit 24 Intensity distribution determination unit 25 Statistical analysis unit 26 Submillimeter wave beam transmitter 27 Submillimeter wave beam emission position 28 Submillimeter wave beam transmission system 29 Polarization angle rotation mechanism 30 Distance fine adjustment stage 31 Circular slit 32 High parallelism aluminum vapor deposition mirror 33 Positioning pin hole 34 Mounting screw hole 35 Cover member 36 Transmission side coordinate system 37 Reception side coordinate system

Claims (16)

A collimator comprising: a collimated light transmitting unit that transmits collimated light; and a reflected light receiving unit that receives reflected light;
A submillimeter wave beam receiving section comprising three or more collimated light reflectors each reflecting a collimated light transmitted from the collimated light transmitting section and a submillimeter wave beam receiving optical system, each disposed at a predetermined position; ,
A position determining unit that determines a position at which light reflected by any of the three or more collimated light reflectors is received in a predetermined coordinate system that defines an emission position of the collimated light; and Using the light receiving positions of the light reflected by the three or more collimated light reflectors determined respectively, the position of the submillimeter wave beam receiver in the predetermined coordinate system and the submillimeter wave with respect to the predetermined coordinate system A position and geometric orientation calculator for calculating the geometric orientation of the beam receiver;
A submillimeter wave beam transmitting unit for transmitting a submillimeter wave beam;
A submillimeter wave beam measuring unit that measures the electromagnetic intensity of the submillimeter wave beam transmitted from the submillimeter wave beam transmitting unit and received by the submillimeter wave beam receiving unit using the submillimeter wave beam receiving optical system;
The submillimeter wave beam calculated by the electromagnetic intensity of the submillimeter wave beam measured by the submillimeter wave beam measurement unit, the emission position of the submillimeter wave beam in the coordinate system, and the position and geometric orientation calculation unit. An intensity distribution determining unit that determines an electromagnetic intensity distribution in the coordinate system of the submillimeter wave beam transmitted from the submillimeter wave beam transmitting unit using the position and geometric orientation of the receiving unit. By performing correction corresponding to an apparent change in the submillimeter wave beam electromagnetic intensity distribution, which occurs depending on the position and geometric orientation of the submillimeter wave beam receiver, the submillimeter wave beam transmitter And determining an electromagnetic intensity distribution in the coordinate system of the submillimeter wave beam transmitted from the submillimeter wave beam. System. A system for determining a position of a specimen in a predetermined coordinate system and a geometric orientation of the specimen relative to the predetermined coordinate system,
A collimator comprising: a collimated light transmitting unit that transmits collimated light; and a reflected light receiving unit that receives reflected light;
Three or more collimated light reflectors that reflect the collimated light transmitted from the collimated light transmitter, each disposed at a predetermined position with respect to the specimen;
A position determining unit that determines a position at which light reflected by any of the three or more collimated light reflectors is received in the predetermined coordinate system that defines an emission position of the collimated light;
Using the light receiving position of the light reflected by the three or more collimated light reflectors determined by the position determining unit, the position of the specimen in the predetermined coordinate system, and the position relative to the predetermined coordinate system A system comprising: a position and geometric orientation calculation unit for calculating a geometric orientation of a specimen. A system for determining a position in a predetermined coordinate system and a geometric orientation with respect to the predetermined coordinate system of a measurement target wavelength band light beam receiving unit including a measurement target wavelength band light beam receiving optical system as the specimen. Because
A measurement target wavelength band light beam transmitting unit that transmits a measurement target wavelength band light beam; and
The electromagnetic intensity of the measurement target wavelength band light beam transmitted from the measurement target wavelength band light beam transmitting section and received by the measurement target wavelength band light beam receiving section using the measurement target wavelength band light beam receiving optical system is measured. A measurement target wavelength band light beam measurement unit,
The electromagnetic intensity of the measurement target wavelength band light beam measured by the measurement target wavelength band light beam measurement section, the emission position of the measurement target wavelength band light beam in the coordinate system, the position and geometric orientation calculation section The coordinates of the measurement target wavelength band light beam transmitted from the measurement target wavelength band light beam transmission unit using the position and geometric orientation of the measurement target wavelength band light beam reception unit calculated by A measurement target wavelength band light beam generated depending on the position and geometric orientation of the measurement target wavelength band light beam receiving unit by further comprising: an intensity distribution determination unit that determines an electromagnetic intensity distribution in the system. After performing correction corresponding to the apparent change in the electromagnetic intensity distribution, the measurement target wavelength band light beam transmitted from the measurement target wavelength band light beam transmission unit in the coordinate system. The system according to claim 2, wherein the electromagnetic intensity distribution is determined.   The measurement target wavelength band light beam transmission unit is a submillimeter wave beam transmission unit that transmits a submillimeter wave beam, and the measurement target wavelength band light beam reception unit includes a submillimeter wave beam reception optical system. The system according to claim 3, wherein the system is a part. A moving mechanism unit that moves the collimator and the measurement target wavelength band light beam transmission unit in the coordinate system, and changes a distance between the collimator and the measurement target wavelength band light beam transmission unit and the specimen; Prepared,
The position determining unit determines a position at which the reflected light is received based on information on the movement of the collimator in the coordinate system by the moving mechanism unit, and further, the measurement target wavelength by the moving mechanism unit 5. The configuration according to claim 3, wherein an emission position of the measurement target wavelength band light beam in the coordinate system is determined based on information relating to movement of the range light beam transmitter in the coordinate system. The described system. Using the electromagnetic intensity distribution in the coordinate system of the measurement target wavelength region light beam determined by the intensity distribution determination unit, the beam center position and beam width of the measurement target wavelength region light beam in the coordinate system are determined. First statistical analysis means,
Each electromagnetic intensity distribution determined by the intensity distribution determining unit is determined by the first statistical analysis unit while changing a distance between the measurement target wavelength band light beam transmitting unit and the specimen by the moving mechanism unit. A statistical analysis unit having second statistical analysis means for determining a propagation vector direction and a beam offset of the measurement target wavelength band light beam using each beam center position. To
The system according to claim 5. The reflected light receiving unit is further configured to measure the intensity of the received reflected light,
The position and geometric orientation calculation unit
Each position of the three or more collimated light reflectors in the coordinate system based on two or more light receiving positions determined by the position determining unit as being a position where reflected light having an intensity equal to a predetermined threshold is received. Decide
Using the determined positions of the three or more collimated light reflectors, the position of the specimen in the predetermined coordinate system and the geometric orientation of the specimen with respect to the predetermined coordinate system are calculated. The system according to claim 2, wherein the system is configured as follows. The collimating light reflector is composed of a high parallelism mirror and a covering member pressure-bonded to the high flatness mirror via a packing, and the high parallelism is formed from a slit provided at a predetermined position of the covering member. The system according to claim 2, wherein the system is configured to reflect collimated light incident on the mirror. Transmitting collimated light from a collimated light transmitting unit in the collimator;
Light transmitted from the collimated light transmitting unit and reflected by any one of three or more collimated light reflectors each disposed at a predetermined position with respect to the submillimeter wave beam receiving unit including the submillimeter wave beam receiving optical system. And a step of determining a position where the reflected light is received in a predetermined coordinate system defining an emission position of the collimated light by a position determining unit. When,
Using the light receiving positions of the light reflected by the three or more collimated light reflectors determined by the position determining unit, the position of the submillimeter wave beam receiving unit in the predetermined coordinate system, and the predetermined coordinates Calculating the geometric orientation of the submillimeter wave beam receiver relative to the system by a position and geometric orientation calculator;
Transmitting the submillimeter wave beam by the submillimeter wave beam transmitting unit;
Measuring the electromagnetic intensity of the submillimeter wave beam transmitted from the submillimeter wave beam transmitting section and received by the submillimeter wave beam receiving section using the submillimeter wave beam receiving optical system, by a submillimeter wave beam measuring section;
The submillimeter wave beam calculated by the electromagnetic intensity of the submillimeter wave beam measured by the submillimeter wave beam measurement unit, the emission position of the submillimeter wave beam in the coordinate system, and the position and geometric orientation calculation unit. Determining the electromagnetic intensity distribution in the coordinate system of the submillimeter wave beam transmitted from the submillimeter wave beam transmitting section by the intensity distribution determining section using the position and geometric orientation of the receiving section. By including the sub-millimeter wave beam after performing correction corresponding to an apparent change in the electromagnetic intensity distribution of the sub-millimeter wave beam, which occurs depending on the position and geometric orientation of the sub-millimeter wave beam receiving unit. An electromagnetic intensity distribution in the coordinate system of the submillimeter wave beam transmitted from the transmitter is determined. Beam measurement method. A method for determining the position of a specimen in a predetermined coordinate system and the geometric orientation of the specimen with respect to the predetermined coordinate system,
Transmitting collimated light from a collimated light transmitting unit in the collimator;
The light transmitted from the collimated light transmitting unit and reflected by any one of the three or more collimated light reflectors arranged at predetermined positions with respect to the specimen is reflected by the reflected light receiving unit in the collimator. Receiving light; and
Determining a position at which the reflected light is received in the predetermined coordinate system defining an emission position of the collimated light by a position determining unit;
Using the light receiving position of the light reflected by the three or more collimated light reflectors determined by the position determining unit, the position of the specimen in the predetermined coordinate system, and the position relative to the predetermined coordinate system Calculating the geometric orientation of the specimen by the position and geometric orientation calculating section. In order to determine the position in a predetermined coordinate system and the geometric orientation with respect to the predetermined coordinate system of the measurement target wavelength band light beam receiving unit including the measurement target wavelength band light beam receiving optical system as the specimen. The method of claim 10, wherein:
Transmitting the measurement target wavelength band light beam by the measurement target wavelength band light beam transmitting unit;
The electromagnetic intensity of the measurement target wavelength band light beam transmitted from the measurement target wavelength band light beam transmitting section and received by the measurement target wavelength band light beam receiving section using the measurement target wavelength band light beam receiving optical system is measured. , Measuring by the measurement target wavelength range light beam measurement unit,
The electromagnetic intensity of the measurement target wavelength band light beam measured by the measurement target wavelength band light beam measurement section, the emission position of the measurement target wavelength band light beam in the coordinate system, the position and geometric orientation calculation section The coordinates of the measurement target wavelength band light beam transmitted from the measurement target wavelength band light beam transmission unit using the position and geometric orientation of the measurement target wavelength band light beam reception unit calculated by Determining the electromagnetic intensity distribution in the system by an intensity distribution determining unit, and generating the wavelength light to be measured depending on the position and geometric orientation of the light beam receiving unit to be measured After performing correction corresponding to an apparent change in the beam electromagnetic intensity distribution, the coordinate system of the measurement target wavelength band light beam transmitted from the measurement target wavelength band light beam transmitter is added to the coordinate system. A method characterized by determining an electromagnetic intensity distribution in the chamber.   The step of transmitting the measurement target wavelength region light beam is a step of transmitting a sub millimeter wave beam by a sub millimeter wave beam transmission unit, and the measurement target wavelength region light beam reception unit includes a sub millimeter wave beam receiving optical system. The method according to claim 11, wherein the method is a submillimeter wave beam receiver. The step of transmitting the collimated light and the step of receiving the reflected light move the collimator within the coordinate system using a moving mechanism and change the distance between the collimator and the specimen. Thus, the collimated light is transmitted from an arbitrary emission position in the coordinate system to the collimated light reflector at an arbitrary distance from the autocollimator, and the reflected light is received in the arbitrary light reception in the coordinate system. Each configured to receive light at a location,
In the step of determining the received light position, the position determining unit determines a position where the reflected light is received based on information about movement of the collimator in the coordinate system by the moving mechanism unit. Configured,
The step of transmitting the measurement target wavelength band light beam includes moving the measurement target wavelength band light beam transmission section in the coordinate system using the moving mechanism section and the measurement target wavelength band light beam transmission section and the supply. By changing the distance to the specimen, the measurement target wavelength band light beam is transmitted from an arbitrary emission position in the coordinate system to the specimen at an arbitrary distance from the measurement target wavelength band light beam transmission unit. Configured to
The step of determining the electromagnetic intensity distribution of the measurement target wavelength band light beam in the coordinate system by the intensity distribution determination unit relates to the movement of the measurement target wavelength band light beam transmission unit in the coordinate system by the moving mechanism unit. Based on the information, the position determining unit determines an emission position of the measurement target wavelength band light beam in the coordinate system, and the electromagnetic intensity distribution is determined using the determined emission position. 13. A method according to claim 11 or 12, characterized. Using the electromagnetic intensity distribution in the coordinate system of the measurement target wavelength region light beam determined by the intensity distribution determination unit, the beam center position and the beam width of the measurement target wavelength region beam in the coordinate system are set to the first A stage of determination by means of statistical analysis;
Each electromagnetic intensity distribution determined by the intensity distribution determining unit is determined by the first statistical analysis unit while changing a distance between the measurement target wavelength band light beam transmitting unit and the specimen by the moving mechanism unit. Using the second statistical analysis means to determine the propagation vector direction and beam offset of the measurement target wavelength band light beam using each beam center position,
Further comprising:
The method of claim 13. The method further includes the step of measuring the intensity of the reflected light received by the reflected light receiving unit,
Calculating the position of the specimen in the predetermined coordinate system and the geometric orientation of the specimen relative to the predetermined coordinate system;
By the position and geometric orientation calculation unit,
Each position of the three or more collimated light reflectors in the coordinate system based on two or more light receiving positions determined by the position determining unit as being a position where reflected light having an intensity equal to a predetermined threshold is received. A step of determining
Using the determined positions of the three or more collimated light reflectors, the position of the specimen in the predetermined coordinate system and the geometric orientation of the specimen with respect to the predetermined coordinate system are calculated. The method according to any one of claims 10 to 14, characterized in that it is a step consisting of: Transmitting collimated light from a collimated light transmitting unit in the collimator;
Light transmitted from the collimated light transmitting unit and reflected by any one of three or more collimated light reflectors each disposed at a predetermined position with respect to the submillimeter wave beam receiving unit including the submillimeter wave beam receiving optical system. Receiving by the reflected light receiving unit of the collimator, and determining by a position determining unit the position where the reflected light is received in a predetermined coordinate system that defines the emission position of the collimated light; ,
Using the light receiving positions of the light reflected by the three or more collimated light reflectors determined by the position determining unit, the position of the submillimeter wave beam receiving unit in the predetermined coordinate system, and the predetermined coordinates A step of calculating a geometric orientation of the submillimeter wave beam receiving unit with respect to the system by a position and a geometric orientation calculating unit is selected by moving the collimator using a moving mechanism unit, Performing with respect to a predetermined distance between the collimator and the submillimeter wave beam receiver, and maintaining the predetermined distance,
Transmitting the submillimeter wave beam by the submillimeter wave beam transmitting section from the submillimeter wave beam emitting position having a known displacement with respect to the collimated light emitting position in the collimated light transmitting section;
Measuring the electromagnetic intensity of the submillimeter wave beam transmitted from the submillimeter wave beam transmitting section and received by the submillimeter wave beam receiving section using the submillimeter wave beam receiving optical system, by a submillimeter wave beam measuring section;
The sub-millimeter wave beam transmitting unit is moved while moving in the coordinate system using the moving mechanism unit,
The sub-millimeter wave beams respectively measured by the sub-millimeter wave beam measurement unit are measured with respect to the electromagnetic intensity distribution in the coordinate system of the sub-millimeter wave beam transmitted from the sub-millimeter wave beam transmission unit defined for the predetermined distance. And the position and geometric orientation of the submillimeter wave beam receiving unit calculated by the position and geometric orientation calculating unit. , And determined by the intensity distribution determination unit,
By changing the distance between the collimator and the submillimeter wave beam receiving unit and determining the electromagnetic intensity distribution, the 3 mm of the electromagnetic intensity of the submillimeter wave transmitted from the submillimeter wave beam transmitting unit is determined. A submillimeter wave beam measuring method characterized by determining a dimensional distribution.

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