JP5823810B2 - Observation device - Google Patents

Description

  The present invention relates to an apparatus for observing a fluorescent image of an object.

  Since it is difficult to observe a colorless and transparent object (phase object) such as a cell or a glass body based on an intensity distribution (amplitude image) of transmitted light generated when the object is irradiated with light, An endogenous or exogenous fluorescent substance is illuminated with excitation light, and a fluorescent image generated on the object is observed. Examples of the fluorescence from the endogenous fluorescent substance include autofluorescence. Examples of fluorescence from an exogenous fluorescent material include fluorescence from a fluorescent material labeled on an object. A fluorescence microscope is known as an apparatus for observing a fluorescent image of such an object. However, when a fluorescent image of a moving object is obtained using a fluorescence microscope, there is a problem that the photographing speed and image quality are limited.

  As a technique for observing a fluorescent image of a moving object, a technique using a Time Delay Integration (TDI) system described in Patent Document 1 and Non-Patent Document 1 is known. In an observation apparatus based on the TDI system, an image of an object is formed on a light receiving surface of a camera (hereinafter referred to as a TDI camera) incorporating the TDI system, and the movement of the image and the movement of charges within the TDI camera ( By completely synchronizing the movement direction of the charges with the movement direction of the image), it is possible to obtain a multi-exposure image without blurring even with a moving object. Therefore, it is possible to clearly capture an image of an object that is a low illuminance image such as a fluorescent image and moves at high speed.

JP-T-2004-506919

H.-S. Yong, et al, "TDI charge coupled devices: Design and applications," IBM J. Res. Develop., Vol. 36, No. 1, 83-106, (1992).

  However, in the observation apparatus using the TDI method described in Patent Document 1 and Non-Patent Document 1, it is necessary to move the charges in synchronization with the movement of the image of the object. If the synchronization is incomplete, a blurred image can be obtained, and as a result, there is a problem that the spatial resolution is impaired.

  The present invention has been made to solve the above-described problems, and provides an observation apparatus capable of obtaining a fluorescent image in which motion blur is eliminated without impairing spatial resolution. Objective.

  The observation apparatus of the present invention includes: (1) a light source unit that excites a fluorescent substance included in a moving object and irradiates the object with light that generates fluorescence from the object; and (2) the light source unit The direction on the predetermined plane in which the Doppler shift effect due to the movement of the object becomes constant in the light that has reached the predetermined plane among the fluorescence generated from the object by the light irradiation by the first direction is defined as the first direction. When the direction on the predetermined plane orthogonal to the second direction is the second direction, it represents the sum of the data in the second direction, which temporally changes at a frequency corresponding to the amount of Doppler shift of the light reaching each position on the predetermined plane. A detection unit that outputs data at each time for each position in the first direction; and (3) a Fourier transform related to a time variable for data having the position and time in the first direction on a predetermined plane as variables, and after this Fourier transform Data Performing a two-dimensional Fourier transform of Te, characterized in that it comprises a calculation unit, the obtaining the data obtained by the two-dimensional Fourier transform as an image of the object. Here, the first direction is a direction perpendicular to the moving direction of the object, and the second direction is a direction parallel to the moving direction of the object.

  In the observation apparatus of the present invention, an object having a moving fluorescent substance is irradiated with excitation light from the light source unit to generate fluorescence. The fluorescent scattered light undergoes an amount of Doppler shift according to the scattering direction. The fluorescent scattered light is received by the detector. The direction on the predetermined plane in which the Doppler shift effect due to the movement of the object is constant in the light reaching the predetermined plane is defined as the first direction, and the direction on the predetermined plane orthogonal to the first direction is defined as the second direction. . Data representing the sum in the second direction of data that changes in time with a frequency corresponding to the amount of Doppler shift of light that has reached each position on the predetermined plane via the optical system is obtained at each time for each position in the first direction. Is output from the detector. In the calculation unit, Fourier transformation is performed on the time variable for the data having the position and time in the first direction on the predetermined plane as variables, and two-dimensional Fourier transformation is performed on the data after the Fourier transformation. Data obtained by Fourier transform is obtained as an image of the object.

  The detection unit (a) inputs fluorescence generated from the object by the light output from the light source unit, divides the input fluorescence into two at the subsequent stage of the object, and outputs the first light and the second light. And an optical system that heterodyne interferes the first light and the modulated second light on a predetermined plane after the second light is modulated by the modulator, and (b) has a light receiving surface on the predetermined plane. And a photodetector having a pixel structure in the first direction on the light receiving surface.

  The calculation unit includes a first Fourier transform unit that performs a one-dimensional Fourier transform on a time variable, and a second Fourier transform unit that performs a two-dimensional Fourier transform. The second Fourier transform unit performs a one-dimensional Fourier transform on a frequency. You may provide the 3rd Fourier-transform part to perform, and the 4th Fourier-transform part which performs the one-dimensional Fourier transform regarding a 1st direction.

  The observation apparatus according to the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is a back focal plane in the first direction of the lens, and the rear in the second direction of the lens. It may be arranged on the focal plane, and may be arranged in the order of the light source unit, the lens, the detection unit, the first Fourier transform unit, the third Fourier transform unit, and the fourth Fourier transform unit.

  The observation apparatus according to the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is a surface on which the Franforfer diffraction image of the object is formed in the first direction by the lens. And arranged on a surface on which a francophor diffraction image of the object is formed in the second direction, and includes a light source unit, a lens, a detection unit, a first Fourier transform unit, a third Fourier transform unit, and a fourth Fourier transform unit. They may be arranged in order.

  The observation apparatus according to the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is a surface on which the Franforfer diffraction image of the object is formed in the first direction by the lens. It is arranged on the imaging plane where the image of the object is formed in the second direction, and is arranged in the order of the light source unit, lens, detection unit, first Fourier transform unit, third Fourier transform unit, and fourth Fourier transform unit. It may be done.

  The observation apparatus according to the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is a surface on which the Franforfer diffraction image of the object is formed in the first direction by the lens. It is arranged on the surface where the Fresnel diffraction image of the object is formed in the second direction, and is arranged in the order of the light source unit, the lens, the detection unit, the first Fourier transform unit, the third Fourier transform unit, and the fourth Fourier transform unit. It may be done.

  The observation apparatus of the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is an imaging surface on which an image of the object is formed in the first direction by the lens. , Arranged on the surface on which the Franforfer diffraction image of the object is formed in the second direction, the light source unit, the lens, the detection unit, the first Fourier transform unit, the fourth Fourier transform unit, the third Fourier transform unit, the fourth The lenses may be arranged in the order of the Fourier transform unit, and the lens may perform one-dimensional Fourier transform in the first direction.

  The observation apparatus of the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is an imaging surface on which an image of the object is formed in the first direction by the lens. The light source unit, the lens, the detection unit, the first Fourier transform unit, the fourth Fourier transform unit, the third Fourier transform unit, and the fourth Fourier transform are arranged on the image plane on which an image of the object is formed in the second direction. The lenses may be arranged in the order of the parts, and the lens may perform a one-dimensional Fourier transform in the first direction.

  The observation apparatus of the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is an imaging surface on which an image of the object is formed in the first direction by the lens. The light source unit, the lens, the detection unit, the first Fourier transform unit, the fourth Fourier transform unit, the third Fourier transform unit, and the fourth Fourier transform are arranged on the surface where the Fresnel diffraction image of the object is formed in the second direction. The lenses may be arranged in the order of the parts, and the lens may perform a one-dimensional Fourier transform in the first direction.

  The observation apparatus of the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is a surface on which a Fresnel diffraction image of the object is formed in the first direction by the lens. , Arranged on the surface on which the Franforfer diffraction image of the object is formed in the second direction, the light source unit, the lens, the detection unit, the first Fourier transform unit, the third Fourier transform unit, the fourth Fourier transform unit, the fourth It may be arranged in the order of the Fourier transform unit.

  The observation apparatus of the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is a surface on which a Fresnel diffraction image of the object is formed in the first direction by the lens. The light source unit, the lens, the detection unit, the first Fourier transform unit, the third Fourier transform unit, the fourth Fourier transform unit, and the fourth Fourier transform are arranged on the image plane on which an image of the object is formed in the second direction. It may be arranged in the order of the parts.

  The observation apparatus of the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is a surface on which a Fresnel diffraction image of the object is formed in the first direction by the lens. The light source unit, the lens, the detection unit, the first Fourier transform unit, the third Fourier transform unit, the fourth Fourier transform unit, and the fourth Fourier transform are arranged on the surface where the Fresnel diffraction image of the object is formed in the second direction. It may be arranged in the order of the parts.

  The observation apparatus of the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is a surface on which a Fresnel diffraction image of the object is formed in the first direction by the lens. The light source unit, the lens, the detection unit, the first Fourier transform unit, the fourth Fourier transform unit, the third Fourier transform unit, and the fourth Fourier transform are arranged on the surface where the Fresnel diffraction image of the object is formed in the second direction. It may be arranged in the order of the parts.

  An observation apparatus according to the present invention excites a fluorescent material of a moving object and irradiates the object with light that generates fluorescence from the object, and irradiates the object with light from the light source. A direction on the predetermined plane in which the Doppler shift effect due to the movement of the object is constant in the light that has reached the predetermined plane among the generated fluorescence, and the direction perpendicular to the movement direction of the object is the first direction, Depending on the Doppler shift amount of light reaching each position on the predetermined plane when the second direction is a direction on the predetermined plane orthogonal to the first direction and parallel to the moving direction of the object. A detector that outputs data representing the sum in the second direction of data that changes with time at a different frequency at each time for each position in the first direction, and a position and time in the first direction on a predetermined plane. About data as variables An arithmetic unit that performs one-dimensional Fourier transform on a time variable, one-dimensional Fourier transform on a frequency, and one-dimensional Fourier transform on a first direction, and obtains data obtained by these one-dimensional Fourier transforms as an image of an object; And the detection unit inputs fluorescence generated from the object by the light output from the light source unit, and divides the input fluorescence into two at the subsequent stage of the object, and the first light and the second light And an optical system for heterodyne interference between the first light and the modulated second light on a predetermined plane after the second light is modulated by the modulator, and a light receiving surface on the predetermined plane. And a photodetector having a pixel structure in a first direction on the surface.

  The observation apparatus of the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is an imaging surface on which an image of the object is formed in the first direction by the lens. , Arranged in the imaging plane where the image of the object is formed in the second direction, arranged in the order of the light source unit, lens, detection unit, first Fourier transform unit, third Fourier transform unit, the lens in the first direction It may include an effect of performing a one-dimensional Fourier transform.

  The observation apparatus of the present invention further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is an imaging surface on which an image of the object is formed in the first direction by the lens. , Arranged in the second direction on the surface on which the Franforfer diffraction image of the object is formed, arranged in the order of the light source unit, the lens, the detection unit, the first Fourier transform unit, the third Fourier transform unit, It may include an effect of performing a one-dimensional Fourier transform in one direction.

  The lens further includes a lens disposed between the light source unit and the detection unit, and the light receiving surface of the detection unit is an imaging surface on which an image of the object is formed in the first direction by the lens, and the object in the second direction. Are arranged on the surface on which the Fresnel diffraction image is formed, and are arranged in the order of the light source unit, the lens, the detection unit, the first Fourier transform unit, and the third Fourier transform unit, and the lens performs one-dimensional Fourier transform in the first direction. It may include an action.

  In the observation apparatus of the present invention, the calculation unit may further include an initial phase correction unit that corrects an initial phase included in data obtained by the one-dimensional Fourier transform regarding the time variable.

  In the observation apparatus of the present invention, there may be a plurality of detection units, and the calculation unit may further include an output totalizer that calculates the sum of outputs from the plurality of detection units.

  The observation apparatus of the present invention may further include a second direction conversion unit that performs Fourier transformation or Fresnel transformation relating to the second direction.

  In the observation apparatus of the present invention, the calculation unit performs two-dimensional Fourier analysis on data in a region including the Nyquist frequency before and after the difference frequency between the first modulation frequency and the second modulation frequency among the data obtained by Fourier transform. Conversion may be performed.

  In the observation apparatus of the present invention, the calculation unit is a region of the data including the Nyquist frequency before and after the difference frequency between the first modulation frequency and the second modulation frequency in the data obtained by the one-dimensional Fourier transform regarding the time variable. The data may be subjected to a one-dimensional Fourier transform relating to the frequency and a one-dimensional Fourier transform relating to the first direction.

  In the observation apparatus of the present invention, the modulator is configured as a single modulator, and the arithmetic unit calculates the modulation frequency in the single modulator or the modulation frequency of the data obtained by the one-dimensional Fourier transform relating to the time variable. Two-dimensional Fourier transform may be performed on data in a region including the Nyquist frequency around the harmonic wave.

  In the observation apparatus of the present invention, the modulator is configured as a single modulator, and the arithmetic unit calculates the modulation frequency in the single modulator or the modulation frequency of the data obtained by the one-dimensional Fourier transform relating to the time variable. One-dimensional Fourier transform related to the frequency and one-dimensional Fourier transform related to the first direction may be performed on data in a region including the Nyquist frequency around the harmonic wave.

  The observation apparatus of the present invention may further include a speed detection unit that detects the moving speed of the object. In this case, the calculation unit can perform correction related to the speed change of the object in the time direction one-dimensional Fourier transform or two-dimensional Fourier transform based on the speed of the object detected by the speed detection unit.

  In the observation apparatus of the present invention, the light irradiation to the object may be an optical arrangement of transmitted illumination, an optical arrangement of reflected illumination, or an optical arrangement of limit illumination. Good. In the observation apparatus of the present invention, the light source unit may be a light source that generates light in a single longitudinal mode or a light source that generates broadband light. In the latter case, a mode-locked laser is used. There may be.

  In the observation apparatus of the present invention, the detector may further include a filter that is disposed in front of the light receiving surface, blocks light from the light source unit, and transmits fluorescence generated from the object.

  According to the present invention, it is possible to obtain a fluorescent image that eliminates motion blur caused by movement without impairing the spatial resolution.

It is a figure explaining the principle of acquisition of the fluorescence image of the target object by the observation apparatus of this embodiment. It is a figure explaining the scattering direction of the fluorescence scattered light which arises in a target object. It is a figure explaining the position where the scattered light of the fluorescence which arises in a subject reaches the back focal plane of a lens. It is a figure which further demonstrates the position where the scattered light of the fluorescence which arises in a target object arrives at the back focal plane of a lens. It is a figure explaining the position where the scattered light of the fluorescence which arises in a subject reaches the back focal plane of a lens when a subject moves. It is a figure explaining the change of the optical path length until the scattered light of the fluorescence which arises in a target object reaches a back focal plane of a lens when a target object moves. It is a figure explaining the angle which the scattering direction unit vector of the fluorescence scattered light which arises in a target object, and the speed vector of the moving target object make. It is a figure which shows the structure of the observation apparatus 1 of this embodiment. It is a figure which shows the detailed structure of the observation apparatus 1 of this embodiment. It is a figure explaining the arrangement | positioning relationship between the target object 2, the lens 40, and the photodetector 46 in the observation apparatus 1 of this embodiment. It is a figure which shows the structural example of the lens 40 contained in the observation apparatus 1 of this embodiment. It is a figure which shows typically the signal observed on a uv plane when the 1st example of arrangement | positioning is employ | adopted in the observation apparatus 1 of this embodiment. The figure which shows typically the signal observed on a uv plane when it is a case where the 1st arrangement example is employ | adopted in the observation apparatus 1 of this embodiment, and there is no frequency shift by the modulators 20 and 30 (ohm = 0). It is. When the observation apparatus 1 of the present embodiment employs the first arrangement example, the signal s ₁ which represents the sum of the signal h ₁ to h _N on v parallel to the direction line for each u _n a (u _n, t) It is a figure which shows typically operation to obtain. It is a block diagram which shows the structure of the photon detection part 46 and the calculating part 50 in a 1st arrangement example. It is a figure which shows typically the signal observed on u'v 'plane when the 2nd example of arrangement | positioning is employ | adopted in the observation apparatus 1 of this embodiment. It is a figure which shows the structural example of the lens 40 in the 2nd example of arrangement | positioning. It is a block diagram which shows the structure of the lens 40, the photon detection part 46, and the calculating part 50 in the 2nd example of arrangement | positioning. It is a figure which shows the structural example of the lens 40 in the 3rd example of arrangement | positioning. It is a block diagram which shows the structure of the photon detection part 46 and the calculating part 50 in a 3rd arrangement example. It is a schematic diagram of the calculation by the calculating part 50 of the 4th example of arrangement | positioning. It is a block diagram which shows the structure of the photon detection part 46 and the calculating part 50 in the 4th example of arrangement | positioning. It is a schematic diagram of the calculation by the calculating part 50 of the 5th example of arrangement | positioning. It is a block diagram which shows the structure of the photon detection part 46 and the calculating part 50 in a 5th example of arrangement | positioning. It is a schematic diagram of the calculation by the calculating part 50 of the 6th arrangement example. It is a block diagram which shows the structure of the photon detection part 46 and the calculating part 50 in the 6th example of arrangement | positioning. It is a figure which shows the structural example of the lens 40 in the 7th arrangement example. It is a figure which shows the structural example of the lens 40 in the 8th example of arrangement | positioning. It is a figure which shows the structural example of the lens 40 in the 9th arrangement example. It is a figure which shows the structural example of the lens 40 in a 10th arrangement example. It is a figure which shows the structural example of the lens 40 in the 11th arrangement example. It is a figure which shows the structural example of the lens 40 in the 12th arrangement example. It is a figure which shows the structural example of the lens 40 in the 13th arrangement example. It is a figure which shows the structural example of the lens 40 in the 14th arrangement example. It is a figure which shows the structural example of the lens 40 in the 15th arrangement example. It is a block diagram which shows the outline of a calculator structure in the 1st-15th arrangement example. It is a block diagram which shows the outline of a calculator structure in the 16th arrangement example. It is a block diagram which shows the modification of the outline of the arithmetic unit structure in the 16th arrangement example. It is a block diagram which shows the modification of the outline of the arithmetic unit structure in the 16th arrangement example. It is a block diagram which shows the modification of the outline of the arithmetic unit structure in the 16th arrangement example. It is a block diagram which shows the modification of the outline of the arithmetic unit structure in the 16th arrangement example. It is a graph which shows the time waveform s ^(m) (u, t) in the 16th arrangement example. It is a graph which shows time waveform S ^(m) (u, ω) in the 16th arrangement example. It is a block diagram which shows the modification of the outline of the arithmetic unit structure in the 18th arrangement example. It is a block diagram which shows the structure of the modification of the 17th-19th arrangement example. It is a block diagram which shows the structure of the modification of the 17th-19th arrangement example. It is a figure which shows the lens structure in the 20th arrangement example. It is a figure which shows the structure of the observation apparatus 1 in the 21st arrangement example.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

  The observation apparatus of the present embodiment uses the Doppler shift effect that is generated when light is irradiated to a moving object, and in particular, is constant between the scattering direction of the fluorescence generated in the object and the Doppler shift amount. The fluorescence image of the object is acquired by utilizing the above relationship. First, the fundamental matters regarding acquisition of a fluorescent image of an object by the observation apparatus of the present embodiment will be described with reference to FIGS.

  FIG. 1 is a diagram for explaining the principle of acquisition of a fluorescent image of an object by the observation apparatus of the present embodiment. In this figure, the ξη coordinate system, the xy coordinate system, and the uv coordinate system are shown. The ξ axis, η axis, x axis, y axis, u axis, and v axis are all perpendicular to the optical axis of the lens 40. The ξ axis, the x axis, and the u axis are parallel to each other. The η axis, the y axis, and the v axis are parallel to each other. The object 2 to be observed exists on the ξη plane. The lens 40 exists on the xy plane. Further, the rear focal plane of the lens 40 coincides with the uv plane. The distance between the ξη plane and the xy plane is d. The distance between the xy plane and the uv plane coincides with the focal length f of the lens 40.

It is assumed that the object 2 has a fluorescent material and moves in the -η direction on the ξη plane. It is assumed that the object 2 is irradiated with light L0 traveling in the ζ direction perpendicular to the ξη plane. Here, the light L <b> 0 is excitation light that excites the fluorescent material included in the object 2. This light L0 is, for example, a plane wave. When the object 2 is irradiated with the light L0, the fluorescent material of the object 2 is excited, and fluorescence is generated from the object. This fluorescence becomes scattered light traveling in various directions. The fluorescent scattered lights L _{1 to} L ₃ undergo a Doppler shift due to the movement of the object 2. Scattered light L ₁ fluorescence having a scattering direction vector component in the same direction as the moving direction of the object 2, the optical frequency increases. The scattered light L ₂ that does not have the scattering direction vector component in the moving direction of the object 2 does not change the optical frequency. Scattered light L ₃ of the fluorescent light having a scattering direction vector component in the movement direction opposite to the direction of the object 2, the light frequency decreases. These scattered lights L _{1 to} L ₃ reach the uv plane via the lens 40.

  FIG. 2 is a diagram for explaining the scattering direction of fluorescent scattered light (hereinafter also simply referred to as scattered light) generated in an object. In order to express the scattering direction of the scattered light generated by the object 2, it is necessary to describe with two variables of the elevation angle θ and the azimuth angle φ. The point light source virtually arranged in the object 2 is set as the origin of the ξηζ coordinate system. The angle formed by the direction vector of scattered light from the point light source located at the origin and the ζ axis is defined as an elevation angle θ. Further, an angle formed by the projection vector of the scattering direction vector on the ξη plane and the ξ axis is defined as an azimuth angle φ.

  FIG. 3 is a diagram for explaining a position where scattered fluorescent light generated in the object reaches the rear focal plane of the lens. The fluorescent scattered light generated by irradiating the object 2 with the light L0 can be handled as light emitted from a point light source virtually arranged in the object 2. In the figure, five virtual point light sources are arranged in the object 2. These point light sources may exist not only on the front focal plane of the lens 40 but also before and after the front focal plane of the lens 40.

Of the light emitted from these point light sources, scattered light L _{1 to} L ₃ having the same elevation angle θ and azimuth angle φ reaches one point Pa on the rear focal plane of the lens 40. The other scattered light L _{4 to} L ₆ having the same elevation angle θ and azimuth angle φ reaches another point Pb on the rear focal plane of the lens 40. Since the light rays L ₂ and L ₅ are light emitted from the point light source at the front focal position of the lens 40, the light rays L ₂ and L ₅ travel in parallel to the optical axis of the lens 40 after the lens 40. Of the light L0, the light that has not been scattered by the object 2 travels parallel to the optical axis of the lens 40 and is incident on the lens 40, and is thus collected at the rear focal position Po of the lens 40.

If the object 2 is moving in the -η direction on ξη plane, due to the Doppler shift effect, the optical frequency observed at point Pa is smaller than the original optical frequency f _b, the optical frequency observed at the point Pb is larger than the original optical frequency _{f b.} Since the scattering angle (elevation angle θ, azimuth angle φ) is developed on the rear focal plane of the lens, an image on the rear focal plane is sometimes called an angle spectrum. A light beam having a large elevation angle θ is collected at a position far from the center point Po on the rear focal plane of the lens. In summary, even with different virtual point light sources, scattered light having the same scattering angle is collected at one point on the focal plane after the lens.

FIG. 4 is a diagram for further explaining the position where the fluorescent scattered light generated in the object reaches the rear focal plane of the lens. Here, it is assumed that scattered lights L _{1 to} L ₃ are emitted from different virtual point light sources existing on the front lens focal plane in the object 2 at different scattering angles. The scattered light L ₄ emitted from the virtual point light source at the front focal position of the lens 40 proceeds parallel to the optical axis of the lens 40 after the lens 40 and passes through the point Ps on the rear focal plane of the lens 40. If the scattered light L ₁ emitted from a virtual point light source on the front focal plane of the lens 40 has the same scattering angle as the scattered light L 4 emitted from the virtual point light source at the front focal position of the lens 40, the lens 40. Passes through the point Ps on the rear focal plane. The scattered light L ₂ emitted from the virtual point light source at the front focal position of the lens 40 has a scattering angle different from that of L _4, and therefore proceeds in parallel to the optical axis of the lens 40 after the lens 40 but does not pass through the point Ps. If the scattered light L3 emitted from some other virtual point light source on the front focal plane of the lens 40 passes through the center of the lens 40, the traveling direction does not change before and after the incidence of the lens 40. Eventually, the light beams L _{1 to} L ₃ are collected at a point Pr further rearward from the rear focal plane of the lens. Scattered light having different scattering angles does not intersect at one point on the focal plane after the lens.

  FIG. 5 is a diagram for explaining a position where fluorescent scattered light generated in the object reaches the back focal plane of the lens when the object moves. Here, the objects 2a to 2e moved to the respective positions are shown. Further, it is assumed that virtual point light sources exist in the objects 2a to 2e. The virtual point light source in the object 2a exists at the front lens focal position. The virtual point light sources in the objects 2b and 2c exist above and below the position of the virtual point light source in the object 2a. The virtual point light sources in the objects 2d and 2e exist before and after the position of the virtual point light source in the object 2a. Since the spatially uniform light L0 is irradiated onto the objects 2a to 2e, the intensity distribution of the angular spectrum of the scattered light emitted from each point light source in the objects 2a to 2e is constant. That is, even if the object 2 moves, the intensity distribution of the angle spectrum on the rear focal plane of the lens is constant.

As the object 2 moves, the phase of light changes. For example, the optical path length difference until the lights L _1b and L _1c emitted from the point light sources in the objects 2b and 2c on the front lens focal plane reach the position Pa on the rear lens focal plane is as follows. . The optical path length until the light L _1b emitted from the point light source in the object 2b reaches the incident surface of the lens 40 and the light L _1c emitted from the point light source in the object 2c to the incident surface of the lens 40 The optical path lengths are equal to each other. However, the thickness difference of the lens 40, the light L _1b, L _1c respective optical path length to reach the point P _a from the entrance surface of the lens 40 will be different. As the object 2 moves at a constant speed, the optical path length difference changes linearly with time.

  FIG. 6 is a diagram for explaining the change in the optical path length until the fluorescent scattered light generated in the object reaches the back focal plane of the lens when the object moves. However, it is assumed here that the scattered light is observed at infinity without using the lens 40. When the object 2 moves from the position of the object 2b to the position of the object 2c on the front lens focal plane, the case where the scattered light is observed at the point Pa is the same as the case where the scattered light is observed at infinity.

When the object 2 moves in the -η direction on the ξη plane, the amount of change ΔL per unit time of the optical path length until the scattered light emitted from the object 2 reaches the point Pp on the uv plane at infinity Is represented by the following formula (1). Here, e _pr is the scattering direction unit vector, and v _p is the velocity vector of the object 2. When this optical path length change amount ΔL per unit time is used, the phase difference, that is, the optical frequency change amount f _d is expressed by the following equation (2). λ is the wavelength of light. When the scattered light is observed at the position Pp on the uv plane, the optical path length of the scattered light reaching the position Pp is changed and the optical frequency is changed by the movement of the object 2. This is the cause of the Doppler shift.

The Doppler shift can also be explained by time axis movement which is one of the properties of Fourier transform. The complex amplitude of the object 2 is represented by g (x), and the Fourier transform of the object 2 is represented by G (k). When the object 2 moves from the position x0 to the position (x0 + x), the Fourier transform G ′ (k) of the object 2 after the movement is expressed by the following equation (3). The term in the exponential function on the right side of equation (3) represents the phase. As the object 2 moves, this phase rotates in proportion to the wave vector k, so that a frequency shift occurs. When the phase in the exponential function is φ, the frequency shift f _d is expressed by the following equation (4). e _pr is a unit vector of the wave vector k. v _p represents the time derivative of the position x, that is, the velocity of the object 2. This equation (4) is in agreement with the frequency shift equation (2) described from the change in optical path length per unit time described above.

FIG. 7 is a diagram for explaining the angle formed by the unit vector of the scattering direction of the fluorescent scattered light generated in the object and the velocity vector of the object 2. An angle formed by a vector obtained by projecting the scattering direction unit vector e _pr onto the ηζ plane and the ζ axis is represented by θ ′. At this time, the angle formed by the scattering direction unit vector e _pr and the velocity vector v _{p of the} object 2 is θ ′ + π / 2. From this, the inner product of the scattering vector and the velocity vector on the right side of the equation (2) or (4) is expressed by the following equation (5). V is the speed of movement of the object 2. Since the numerical aperture NA of the lens 40 is defined by sin θ ′, the Nyquist frequency f _nyq for obtaining a blur-free image is expressed by the following equation (6).

Next, by applying specific numerical values to estimate the amount of change f _d of the optical frequency due to the Doppler shift. Assume that the moving speed of the object 2 is 1 m / sec, assuming that the object 2 flows with a flow cytometer currently on the market. The light L0 irradiated to the object 2 is assumed to be argon laser light having a wavelength of 488 nm. It is assumed that fluorescence having a wavelength of 520 nm is excited by the excitation light of the light L0. The lens 40 has an NA of 0.45 and a magnification equivalent to 20 times. When such a lens 40 is used, the maximum value of the sine of the scattering angle θ ′ with respect to the velocity vector v _p is 0.45. Therefore, the maximum Doppler shift frequency is estimated to be 860 kHz from the equation (5). If the speed is 100 μm / second, a maximum Doppler shift frequency of 86 Hz is observed.

The scattered light having the scattering angle θ ′ reaches the position represented by the following expression (7) on the uv plane by the lens 40 having the focal length f. Therefore, using the equations (5) and (7) and using the approximate equation of tanθ′≈sinθ ′ that holds when the angle θ ′ is small, the Doppler shift frequency f _d is expressed by the following equation (8): It can be expressed as a function of the v coordinate value. When approximation is not used, it is expressed by the following equation (9).

  The observation apparatus 1 according to the present embodiment acquires a fluorescent image of the object 2 based on the principle described above. The object 2 is an observation object and contains a fluorescent material such as FITC (fluorescein isothiocyanate). This fluorescent substance is excited by light having a wavelength of 488 nm and emits fluorescence having a wavelength of 520 nm. FIG. 8 is a diagram showing a configuration of the observation apparatus 1 of the present embodiment. The observation apparatus 1 of this embodiment includes a light source unit 10, an illumination lens 11, a beam splitter 12, a first modulator 20, a first signal generator 21, a first amplifier 22, a second modulator 30, and a second signal generator 31. , A second amplifier 32, a lens 40, a beam splitter 41, a mirror 42, a mirror 43, a lens 44, a filter 45, a photodetector 46, and a calculation unit 50. The lens 40 includes a lens 401 and a lens 402. FIG. 9 is a diagram showing the configuration of the above observation apparatus 1 in more detail.

The light source unit 10 is, for example, an argon laser light source, and is an excitation light source that outputs excitation light that excites a fluorescent substance included in the object 2. The light source unit 10 irradiates the object 2 with excitation light having a wavelength of 488 nm and excites the fluorescent material of the object 2 to generate fluorescence (light frequency f _b ) having a wavelength of 520 nm. The beam splitter 12 is disposed between the lens 401 and the lens 402. The beam splitter 12 inputs fluorescence generated from the object by the light output from the light source unit 10, and divides the input fluorescence into two at the subsequent stage of the object 2 to be the first light and the second light. The first light is output to the beam splitter 41 via the lens 402, and the second light is output to the first modulator 20. Each of the first modulator 20 and the second modulator 30 is, for example, an acousto-optic element. The first modulator 20 is supplied with the first modulation signal output from the first signal generator 21 and amplified by the first amplifier 22, diffracts the light output from the light source unit 10, and converts the diffracted light into the first light. 2 output to the modulator 30. The second modulator 30 receives the second modulation signal output from the second signal generator 31 and amplified by the second amplifier 32, diffracts the light output from the first modulator 20, and the diffracted light. Is output to the mirror 42.

  The intensity of each of the first modulation signal supplied to the first modulator 20 and the second modulation signal supplied to the second modulator 30 is, for example, 29 dBm. The frequency of the first modulation signal (first modulation frequency) and the frequency of the second modulation signal (second modulation frequency) are slightly different. For example, the first modulation frequency is 40 MHz, the second modulation frequency is 40.00100 MHz, and the frequency difference between them is 10 Hz. Each of the first modulation signal and the second modulation signal is a sine wave. In order to obtain synchronization between the first signal generator 21 and the second signal generator 31, the first signal generator 21 and the second signal generator 31 are connected by wiring. When the first modulator 20 and the second modulator 30 are acousto-optic elements, m-order diffracted light from the first modulator is input to the second modulator 30, and n-order diffracted light from the second modulator 30 to the mirror 42. Output. m and n are integers and generally take values of m = + 1, n = −1 or m = −1 and n = + 1. In both cases, light that has undergone frequency transition by the frequency Ω = 10 Hz of the difference frequency between the first modulation frequency 40 MHz and the second modulation frequency 40.000010 MHz is output from the second modulator 30.

If the first modulator 20 and the second modulator 30 are collectively referred to as a reference light modulator, the reference light modulator may be anything as long as it has a role of shifting the frequency of light by a frequency Ω. There may be one or more modulators constituting the optical modulator. Optical frequency f _b input to the reference light modulator also by the action of the reference light modulator, the output light, the light of f _{b +} Omega frequency transitions only Omega is emitted.

  The lens 40 inputs the fluorescence scattered light generated in the object 2 by the light irradiation from the lens 11 and forms a Fourier transform image of the object 2. FIG. 11 shows the configuration of the lens 40. As shown in FIG. 11, the lens 40 includes a lens 401 and a lens 402, and the beam splitter 12 is disposed between the lens 401 and the lens 402. In addition, the dotted line in FIG. 11 represents the mode of imaging.

As shown in FIG. 11, a Franforfer diffraction image of the object is obtained on the rear focal plane of the lens 401. Light that has not been subjected to the Doppler effect or light that has a small Doppler effect appears at the center of the Franforfer diffraction image on the rear focal plane of the lens 401. The light gathering at the center of the image in this Franforfer diffraction image is called zero-order light. The 0th order light and the fluorescence that can be regarded as the 0th order light are light that has not been subjected to the Doppler effect or light that has a small Doppler effect among the fluorescence generated in the object 2. In the present specification, these lights are referred to as substantially zero order light. The substantially zero-order light is a unit in the scattering direction in which the Doppler shift frequency f _d shown in the above equation (2) is substantially zero when the unit vector e _pr in the scattering direction and the velocity vector v _{p of the} object 2 are substantially orthogonal. Fluorescence with vector e _pr .

That is, the Doppler shift frequency f _d of the inner substantially zero-order light of the fluorescence generated by the object 2 is substantially zero. The beam splitter 12 is disposed on the rear focal plane of the lens 401 and extracts substantially zero-order light from the fluorescence generated by the object 2. The beam splitter 12 divides the light output from the lens 401 into two, and outputs one of them to the lens 402 as the first light. On the other hand, as shown in FIG. 9, the beam splitter 12 guides the reflected substantially zero-order light as second light to the first modulator 20 via the lens 60, the lens 61, the pinhole 62, and the mirror 63. .

  The front focal plane of the lens 60 coincides with the rear focal plane (uv plane) of the lens 401. The lens 60 outputs substantially zero-order light output from the beam splitter 12 as parallel light. The beam diameter of the parallel light output from the lens 60 is enlarged or reduced by the lens 61. The lens 61 is a so-called 4f optical system composed of two lenses, a lens 501 and a lens 502. The 4f optical system is an optical system in which the rear focal plane of the lens 501 coincides with the front focal plane of the lens 502, and an image of the front focal plane of the lens 501 is formed on the rear focal plane of the lens 502.

  A pinhole 62 is disposed on the rear focal plane of the lens 501. By changing the size of the pinhole 62, the purity of the zero-order light component in the substantially zero-order light extracted by the beam splitter 12 can be adjusted. When the pinhole diameter is small, the purity of the 0th-order light component increases, and when the pinhole diameter is large, the purity of the 0th-order light component decreases. The second light is input to the first modulator via the mirror 63 after the beam diameter and the purity of the zero-order light component are adjusted by the lens 61 and the pinhole 62.

  The lens 11 converts the light output from the light source unit 10 into parallel light and irradiates the object 2 with the parallel light. The lens 44 outputs the light output from the second modulator 30 and sequentially reflected by the mirrors 42 and 43 as parallel light to the beam splitter 41. The lens 44 is composed of a lens 503 and a lens 504, which take the configuration of a 4f optical system. The beam is adjusted to a desired beam diameter by the lens 44 and then input to the beam splitter 41.

  The beam splitter 41 causes light reaching from the lens 40 and the lens 44 to enter the light receiving surface of the photodetector 46, and causes both lights to heterodyne interfere on the light receiving surface. That is, the fluorescence generated from the object 2 by the excitation light output from the light source unit 10 is input to the beam splitter 12, and the input light is split into two by the beam splitter 12 so that the first light and the second light are split. Then, after the second light is modulated by the modulators 20 and 30, the beam splitter 41 causes heterodyne interference between the first light and the modulated second light on a predetermined plane.

A filter 45 is provided in front of the light receiving surface of the photodetector 46. The filter 45 is an optical filter that blocks light output from the light source unit 10 and transmits fluorescence generated in the object 2. Specifically, the filter 45 blocks light having a wavelength of about 448 nm and transmits light having a wavelength of about 520 nm. Only the fluorescence generated from the object 2 is incident on the light receiving surface of the photodetector 46 by the filter 45. The frequency of the light output from the second modulator 30 and incident on the light receiving surface of the photodetector 46 is f _b + Ω. In the case of the observation apparatus 1, the frequency Ω is a difference frequency between the first modulation frequency and the second modulation frequency.

  Assuming that the object 2 is moving in the -η direction on the ξη plane, the Doppler shift frequency due to the movement of the object 2 is constant in the light that has reached the light receiving surface of the photodetector 46 via the lens 40. The first direction is the u direction parallel to the ξ axis. That is, the first direction is a direction perpendicular to the moving direction of the object 2. The second direction on the light receiving surface perpendicular to the first direction is the v direction parallel to the η axis. That is, the second direction is a direction parallel to the moving direction of the object 2. The light detector 46 represents data representing the sum in the second direction (v direction) of data that changes with time at a frequency corresponding to the Doppler shift amount of light that has reached each position on the light receiving surface via the lens 40. , Each position in the first direction (u direction) can be output at each time.

  The photodetector 46 preferably has a pixel structure in the first direction (u direction), and the shape of the photosensitive region of each pixel is preferably long in the second direction (v direction). It is. The light receiving surface of the photodetector 46 is a rear focal plane in the first direction of the lens 40 and may coincide with the rear focal plane in the second direction of the lens 40 (first arrangement example described later). It may be an image plane (imaging plane) on which an image of the object 2 is formed in the first direction by the lens 40, and may coincide with an image plane on which the image of the object 2 is formed in the second direction. (Examples of second and fifth arrangements) Further, both the first direction and the second direction may coincide with an arbitrary surface (Fresnel diffraction surface) perpendicular to the optical axis of the front stage or the rear stage of the lens 40 (third and third directions). 6 arrangement example).

  Further, the light receiving surface of the photodetector 46 is a surface on which the lens 40 forms a franphophor diffraction image of the object in the first direction, and a franphophor diffraction image of the object is formed in the second direction. (The seventh arrangement example), or a surface on which the franphophor diffraction image of the object is formed in the first direction by the lens 40, and the image of the object in the second direction. (An eighth arrangement example), or a surface on which a franphophor diffraction image of the object is formed in the first direction by the lens 40, and is formed in the second direction. May be arranged on the surface on which the Fresnel diffraction image of the object is formed (ninth arrangement example).

  Further, the light receiving surface of the photodetector 46 is an image forming surface on which an image of the object is formed in the first direction by the lens 40, and a surface on which a franphophor diffraction image of the object is formed in the second direction. (The tenth arrangement example), or an imaging plane on which an image of the object is formed in the first direction by the lens 40, and an image of the object is formed in the second direction. It may be arranged on the imaging plane (11th arrangement example), or an imaging plane on which an image of the object is formed in the first direction by the lens 40, and Fresnel diffraction of the object in the second direction It may be arranged on the surface where the image is formed (Twelfth Arrangement Example).

  In addition, the light-receiving surface of the photodetector 46 is a surface on which the Fresnel diffraction image of the object is formed in the first direction by the lens 40, and the Francophor diffraction image of the object is formed in the second direction. May be arranged on a surface (13th arrangement example), or a surface on which a Fresnel diffraction image of the object is formed in the first direction by the lens 40, and an image of the object is formed in the second direction. (Fourteenth arrangement example), or a surface on which a Fresnel diffraction image of the object is formed in the first direction by the lens 40, and the Fresnel of the object in the second direction. You may arrange | position to the surface in which a diffraction image is formed (15th arrangement example).

  The calculation unit 50 obtains an image of the object 2 by performing a predetermined calculation on the data having the position and time in the first direction (u direction) on the light receiving surface output from the photodetector 46 as variables. In order to perform this calculation, the calculation unit 50 includes a first Fourier transform unit 51 that performs a one-dimensional Fourier transform on a time variable, and a second Fourier transform unit 52 that performs a two-dimensional Fourier transform. The second Fourier transform unit 52 includes a third Fourier transform unit 53 that performs a one-dimensional Fourier transform on the frequency, and a fourth Fourier transform unit 54 that performs a one-dimensional Fourier transform on the first direction. Detailed calculation contents will be described later.

  FIG. 10 is a diagram for explaining an arrangement relationship between the object 2, the lens 40, and the photodetector 46 in the observation apparatus 1 of the present embodiment. The figure (a) is the figure seen in the (eta) direction, The figure (b) is the figure seen in the (xi) direction. In the figure, the ξη coordinate system having the origin at the front focal position of the lens 40, the xy coordinate system having the origin at the center of the lens 40, the uv coordinate system having the origin at the rear focal position of the lens 40, and the image plane formed by the lens 40 A u'v 'coordinate system having an origin at the center position and a u "v" coordinate system having an origin at an arbitrary position on the optical axis of the lens 40 are shown. In the first arrangement example, the light receiving surface of the photodetector 46 coincides with the uv plane, in the second arrangement example, the light receiving surface of the photodetector 46 coincides with the u′v ′ plane, and in the third arrangement example, light detection is performed. The light receiving surface of the device 46 coincides with the u "v" plane.

As shown in FIG. 5B, the light beams L _{4 to} L ₆ generated at the same angle by the virtual point light sources g _{1 to} g ₃ in the object 2 are a single point a on the uv plane which is the rear focal plane of the lens. And eventually diverge and reach points h, g, and f on the u′v ′ plane, which is the lens imaging plane. Since these rays L _{4 to} L ₆ have the same scattering angle θ ′, they undergo the same amount of Doppler shift.

  The difference between signals received by the photodetector 46 in each of the first arrangement example and the second arrangement example will be described as follows. In the first arrangement example, the frequency shift is regularly observed in the v direction, and there is a one-to-one correspondence between the position in the v direction and the frequency shift amount. On the other hand, in the second arrangement example, the frequency shift is not regularly arranged in the v ′ direction, and there is no one-to-one correspondence between the position in the v ′ direction and the frequency shift amount.

  Here, the frequency shift amounts irregularly arranged in the v ′ direction in the second arrangement example are ordered (that is, the order is as observed on the light receiving surface of the photodetector 46 in the first arrangement example). In this case, the waveform observed at points f, g, and h on the u′v ′ plane may be combined (added) and then subjected to Fourier transform. By doing so, the frequency axis becomes linear. And its amplitude and phase are obtained.

This is because, in the first arrangement example in which the frequency shifts are regularly arranged in the v direction also on the light receiving surface of the photodetector 46, the waveforms h ₁ , h ₂ , h ₃ in the v direction as shown in the graph of FIG. This is the same as obtaining the amplitude and phase at each frequency by Fourier transformation after the summation. In other words, if the photodetector 46 has a light-receiving surface large enough to cover the scattered light that has been subjected to Doppler shift by the object 2, the photodetector 46 disposed at any position. As a result, the obtained signal does not change and is encoded in frequency, so that the distribution obtained on the light receiving surface of the photodetector 46 in the first arrangement example can be recovered.

  On the other hand, as shown in FIG. 9A, since the Doppler shift is not performed in the u direction, the distribution cannot be recovered by calculation or the like even if the signal is integrated in the u direction. From the above, the photodetector 46 needs to have a pixel structure in the u direction, but does not need to have a pixel structure in the v direction.

  Below, the calculation content of the calculating part 50 at the time of employ | adopting each of the 1st-15th arrangement example in the observation apparatus 1 of this embodiment is demonstrated.

(First arrangement example)
In the first arrangement example, the light receiving surface of the photodetector 46 is disposed on the rear focal plane in the first direction of the lens 40 and the rear focal plane (uv plane) in the second direction of the lens 40. At this time, for the complex amplitude image g (ξ, η) of the object 2 on the ξη plane, the image of the object 2 obtained on the uv plane by the Fourier transform action by the lens 40 is expressed by the following equation (10). The Expression (10) includes a term of the Fourier transform image G (u, v) of the object 2 and completely matches G (u, v) when d = f.

In the configuration of the observation apparatus 1 of this embodiment shown in FIGS. 8 and 9, the scattered light (optical frequency f _b −f _d ) that has undergone Doppler shift in the object 2 and passed through the lens 40, and the first modulator 20. The reference light (optical frequency f _b + Ω) that has undergone a frequency shift from the optical frequency f _b by the second modulator 30 through the beam splitter 41 passes through the beam splitter 41 and the uv plane (photodetector 46) that is the rear focal plane of the lens 40. To the light receiving surface). Due to the heterodyne interference between the two lights on the uv plane, a beat signal having a difference frequency (Ω + f _d ) between the scattered light and the reference light is observed at each position on the uv plane. Optical frequency variation f _d of the scattered light due to the Doppler shift can be expressed as a function of v coordinate value as described above (8). Each optical component in the observation apparatus 1 is arranged so that the optical path of the scattered light is equal to the optical path of the reference light in order to increase the coherence between the scattered light and the reference light.

FIG. 12 is a diagram schematically illustrating signals observed on the uv plane when the first arrangement example is adopted in the observation apparatus 1 of the present embodiment. In this figure, the time waveform of the signal at each of the positions v ₁ , v ₂ , v ₃ on the straight line parallel to the v direction for each u _n (n = 1 to N) on the uv plane is schematically shown. Yes. Since the object 2 is moving in the −η direction on the ξη plane, the frequency (Ω− | f _d ) lower than Ω at the position (u _n , v ₁ ) where the v coordinate value v ₁ is positive on the uv plane. |) Signal h ₁ is obtained. position on the uv plane v coordinate value v2 is 0 _{(u n, v 2)} is the signal _{h 2} of the frequency Ω is obtained. On the uv plane, a signal h ₃ having a frequency (Ω + | f _d |) higher than Ω is obtained at a position (u _n , v ₃ ) where the v coordinate value v ₃ is negative.

FIG. 13 shown as a reference is observed on the uv plane when the first arrangement example is adopted in the observation apparatus 1 of the present embodiment and there is no frequency shift by the modulators 20 and 30 (Ω = 0). It is a figure which shows a signal typically. In this case, a DC signal h3 is obtained at a position (u _n , v ₃ ) where the v coordinate value v ₃ is 0 on the uv plane. On two positions (u _n , v ₁ ) and (u _n , v ₅ ) having the same absolute value of the v coordinate value and different signs on the uv plane, the frequency | f _d | is the same but the phase is only π. Different signals h ₁ and h ₅ are obtained. Similarly, at two positions (u _n , v ₂ ) and (u _n , v ₄ ) having the same absolute value of the v coordinate value and different signs on the uv plane, the frequency | f _d | is the same, but the phase Thus, signals h ₂ and h ₄ that differ by π are obtained.

When the first arrangement example is adopted in the observation apparatus 1 of the present embodiment, the signal h _n observed at the position (u _n , v) on the uv plane which is the rear focal plane of the lens has the frequency Ω + f _d = Ω− ( V / λf) v. That is, the signal h _n observed at the position (u _n , v) has a different frequency depending on the v coordinate value. There is a one-to-one correspondence between v-coordinate values and frequencies. Therefore, if a signal s ₁ (u _n , t) representing the sum of signals h _{1 to} h _N on a straight line parallel to the v direction can be obtained for an arbitrary u _n , this signal s ₁ (u _n , t) is obtained. , The signal (amplitude, phase) at each position (u _n , v) can be specified.

14, when the observation apparatus 1 of the present embodiment employs the first arrangement example, the signal s ₁ (u _n representing the sum of signal h ₁ to h _N on a straight line parallel to the v direction for each u _n , t) is a diagram schematically showing an operation of obtaining t). In this figure, symbol Σ indicates an operation for obtaining the sum of signals h _{1 to} h _N. A signal s ₁ (u, t) representing the sum of signals h (v) on a straight line parallel to the v direction for an arbitrary u coordinate value is expressed by the following equation (11). Here, G (u, v) is a Fourier transform image (complex amplitude) of the object 2 obtained on the uv plane. The symbol ∠ represents the phase of the complex amplitude. φ ₀ represents the initial phase resulting from the optical conditions of the scattered light and the reference light. A ₀ represents intensity unevenness of scattered light and reference light. t is a time variable. The term of DC component is omitted.

As described above, as the photodetector 46, a pixel structure arranged pixel e ₁ to e _n in the u direction, the length in the v direction shape of the photosensitive region of the pixel e _n corresponding to each u _n What is a scale is used suitably. Such signal outputted from the pixel e _n photodetectors 46, corresponding to the above (11) signal s ₁ of the formula (u _n, t).

When the above expression (11) is complexly expressed, it is represented by the following expression (12). ω _d is an angular frequency notation of the Doppler shift frequency f _d , and ω _d = 2πf _d . v = a aω _d, is a = λf / (2πV). In equation (12), A ₀ and φ ₀ are omitted. In the following equations, A ₀ and φ ₀ are omitted.

In the right side of the equation (12), the exponential function exp (iΩt) before the integration symbol means that the function after the integration symbol is modulated at the frequency Ω. Specifically, this means that a frequency transition occurs by a frequency Ω in the frequency domain. Further, (12) integral sign of indicates an inverse Fourier transform of the complex amplitude G (u, v) relates to a variable v or omega _d.

The one-dimensional Fourier transform of the signal s ₁ (u, t) relating to the time variable t is expressed by the following equation (13). The rightmost side of the equation (13) represents a signal that is frequency-shifted by the frequency Δv = aΩ in the two-dimensional Fourier transform image G (u, v) with respect to the complex amplitude image g (ξ, η) of the object 2.

Next, a certain range centered on the frequency Ω = 10 Hz is cut out from the data obtained by subjecting the data of the signal s ₁ (u, t) to a one-dimensional Fourier transform (the above equation (13)) with respect to the time variable t. The fixed range cut out at this time is a region including the Nyquist frequency f _nyq expressed by the above equation (6) around the frequency Ω. By this cut-out operation, G (u, v) shown in the equation (14) is obtained.

  Subsequently, as shown in the following equation (15), the complex amplitude image G (u, v) is two-dimensionally Fourier transformed to obtain a complex amplitude image g (ξ, η) of the object 2.

In the configuration of the observation device 1 of the present embodiment, the light receiving surface of the photodetector 46 is disposed on the rear focal plane in the first direction of the lens 40 and the rear focal plane (uv plane) in the second direction of the lens 40. . In the first arrangement example, the arithmetic unit 50 performs the arithmetic processing as described above to obtain an image of the object 2. That is, the arithmetic unit 50 acquires data of the signal s ₁ (u, t) having the position u on the uv plane and the time t as variables, and the data of the signal s ₁ (u, t) is related to the time variable t. A one-dimensional Fourier transform is performed (the above equation (13)), and data in a region including the Nyquist frequency f _nyq around the frequency Ω is cut out from the data G obtained by the one-dimensional Fourier transform (the above (14) The two-dimensional Fourier transform is performed on the extracted data (formula (15) above), and an image g (ξ, η) of the object 2 is obtained.

FIG. 15 is a diagram illustrating a configuration of the light detection unit 46 and the calculation unit 50 in the first arrangement example in which the calculation processing as described above is performed. The calculation unit 50 includes a first Fourier transform unit 51, a second Fourier transform unit 52, and a specific region cutout unit 55. The second Fourier transform unit 52 includes a third Fourier transform unit 53 and a fourth Fourier transform unit 54. The first Fourier transform unit 51 performs a one-dimensional Fourier transform (the above equation (13)) on the time variable t with respect to the data of the signal s ₁ (u, t) having the position u on the uv plane and the time t as variables. The specific region cutout unit 55 _cuts out data of a region including the Nyquist frequency f _nyq around the frequency Ω from the data G obtained by the one-dimensional Fourier transform (the above equation (14)). Third Fourier transform unit 53 performs this extracted data one-dimensional Fourier transform with respect to time-frequency omega _d (Fourier transform with respect to time-frequency omega _d above (15)). The fourth Fourier transform unit 54 performs a Fourier transform on the variable u (Fourier transform on the variable u in the above equation (15)). Focusing on the Fourier transform unit, in the first arrangement example, the calculation unit 50 is disposed in the order of the first Fourier transform unit 51, the third Fourier transform unit 53, and the fourth Fourier transform unit 54. The position of the fourth Fourier transform unit 54 is not limited to this. For example, the fourth Fourier transform unit 54 may be arranged between the first Fourier transform unit 51 and the third Fourier transform unit 53, or the position of the first Fourier transform unit 51 It may be arranged in front. An image g (ξ, η) of the object 2 is obtained by performing computation on the signal s ₁ (u, t) using such a computation unit 50.

  In the first arrangement example, the light receiving surface of the photodetector 46 only needs to be arranged on the same surface as the back focal plane of the lens 40, and therefore, it is sufficiently far from the object 2 and has Fraunhofer diffraction. You may arrange | position in the plane in the area | region which can be seen.

Here, in order to obtain the data of the signal s ₁ (u, t), the photodetector 46 does not have to have a two-dimensional pixel structure, and may have any one-dimensional pixel structure. . Accordingly, the observation apparatus 1 of the present embodiment has a one-dimensional pixel structure and the fluorescence of the moving object 2 even when the photodetector 46 having a low readout speed per pixel is used. An image can be obtained with high sensitivity. Further, it is possible to obtain a fluorescent image in which motion blur caused by movement is eliminated without impairing the spatial resolution.

  Further, as the photodetector 46, it is also possible to use an on-chip arithmetic function camera (for example, a vision chip or a profile sensor) that can directly calculate the modulation frequency of the detected light within the element. At this time, since an image corresponding to the modulation frequency is directly obtained, the image shown in FIG. 1 can be displayed in real time. Furthermore, if the above-mentioned camera with an on-chip arithmetic function is used, a reconstructed image of speed can be directly output from the detector.

(Second arrangement example)
Next, a second arrangement example will be described. In the second arrangement example, as shown in FIG. 17, the light receiving surface of the photodetector 46 is an imaging surface on which an image of the object 2 is formed in the first direction by the lens 40, and the object in the second direction. It is arranged on the imaging plane (u′v ′ plane) on which two images are formed. As shown in FIG. 10, the light rays L _{1 to} L ₄ reaching the point h on the imaging plane (u′v ′ plane) by the lens 40 are emitted from a common virtual point light source g ₁ in the object 2. It is a thing. Since these light rays L _{1 to} L ₄ have different scattering angles θ ′ when emitted from the virtual point light source g ₁ , the Doppler shift frequencies f _d are also different from each other.

FIG. 16 is a diagram schematically illustrating signals observed on the u′v ′ plane when the second arrangement example is adopted in the observation apparatus 1 of the present embodiment. In the second arrangement example, scattered light having various frequencies is incident on each point on the u′v ′ plane. Therefore, as shown on the left side of the figure, the beat signal h (u ′, v ′) obtained by heterodyne interference between the scattered light and the reference light at each point on the u′v ′ plane has various frequency components. Will be included. The signal observed at the position (u _n ′, v ₁ ′) on the u′v ′ plane is represented as h ₁₀ , the signal observed at the position (u _n ′, v ₂ ′) is represented as h _11, and the position A signal observed at (u _n ′, v ₃ ′) is represented as h ₁₂ . In addition, a signal representing the sum of signals h _{10 to} h ₁₂ on a straight line parallel to the v ′ direction for an arbitrary u _n ′ is represented as s ₂ (u _n ′, t) (center in the figure).

When the signal s ₂ (u _n ′, t) is subjected to a one-dimensional Fourier transform with respect to the time variable t, as shown on the right side of the drawing, along the v direction on the rear focal plane (uv plane) in the case of the first arrangement example. The same frequency distribution is obtained. That is, the irregular frequency distribution (left in the figure) on the u′v ′ plane is converted into a regular frequency distribution (same as the figure) by the one-dimensional Fourier transform of the signal s ₂ (u _n ′, t) with respect to the time variable t. Right). In the second arrangement example, since the light receiving surface of the photodetector 46 is arranged on the image formation plane (u′v ′ plane) by the lens 40, the signal s ₂ (u _n ′, t) is also Fourier-transformed with respect to the variable u ′. By converting, the same distribution as the uv plane can be obtained. The u ′ direction will be described in detail. As a result, the Fourier transform is not performed in the u ′ direction by the optical Fourier transform by the lens 404 in FIG. 17 and the inverse Fourier transform by the calculation unit 50. As a result The distribution regarding the u direction in the first arrangement example is obtained.

  That is, a two-dimensional Fourier transform image G (u, Δv + v) for the complex amplitude image g (ξ, η) of the object 2 can be obtained by the following equation (16). Since the Fourier transform image G (u, Δv + v) is the same as that in the first arrangement example, the complex amplitude image g of the object 2 is obtained by performing the same arithmetic processing as in the first arrangement example. (ξ, η) can be obtained.

In the configuration of the observation apparatus 1 according to the present embodiment, the light receiving surface of the photodetector 46 is an image formation surface on which an image of the object 2 is formed in the first direction by the lens 40, and the object 2 in the second direction. In the second arrangement example arranged on the imaging plane (u′v ′ plane) on which the image is formed, the calculation unit 50 performs the calculation process as described above to obtain an image of the object 2. That is, the operation unit 50, the signal s ₂ to the and time t 'position u on a plane'u'v variable (u ', t) to obtain data, the signal s ₂ (u' of, t) The data is _subjected to Fourier transformation with respect to the variable u ′ and the time variable t (Equation (16) above), and the data in the region including the Nyquist frequency f _nyq around the frequency Ω of the data G obtained by this Fourier transformation is obtained. Cutting out (the above formula (14)), and performing two-dimensional Fourier transform on the cut out data (the above formula (15)), an image g (ξ, η) of the object 2 is obtained.

FIG. 18 is a diagram illustrating a configuration of the lens 40, the light detection unit 46, and the calculation unit 50 in the second arrangement example that performs the calculation process as described above. The computing unit 50 includes a first Fourier transform unit 51, a second Fourier transform unit 52, a fourth Fourier transform unit 54, and a specific region cutout unit 55. The second Fourier transform unit 52 includes a third Fourier transform unit 53 and a fourth Fourier transform unit 54. The first Fourier transform unit 51 uses the time variable t for the data of the signal s ₂ (u ′, t), which has the position u ′ on the u′v ′ plane optically Fourier transformed by the lens 40 and the time t as variables. Fourier transform (Fourier transform related to the time variable t in the above equation (16)). The fourth Fourier transform unit 54 arranged at the subsequent stage of the first Fourier transform unit 51 performs a Fourier transform on the variable u ′ (Fourier transform on the variable u ′ in the above equation (16)) for the data obtained by the Fourier transform. Do. The specific region cutout unit 55 _cuts out data in a region including the Nyquist frequency f _nyq around the frequency Ω from the data G obtained by the Fourier transform (the above equation (14)). Third Fourier transform unit 53 performs this extracted data one-dimensional Fourier transform with respect to time-frequency omega _d (Fourier transform with respect to time-frequency omega _d above (15)). The fourth Fourier transform unit 54 arranged at the subsequent stage of the third Fourier transform unit 53 performs Fourier transform related to the variable u (Fourier transform related to the variable u in the equation (15)). Focusing on the Fourier transform unit, in the second arrangement example, the calculation unit 50 is disposed in the order of the first Fourier transform unit 51, the fourth Fourier transform unit 54, the third Fourier transform unit 53, and the fourth Fourier transform unit 54. In addition, the position of the 4th Fourier-transform part 54 arrange | positioned at the back | latter stage of the 1st Fourier-transform part 51 is not restricted to this, For example, it is arrange | positioned at the back | latter stage of the 3rd Fourier-transform part 53 and the 3rd Fourier-transform part 53. It may be disposed between the fourth Fourier transform unit 54 or may be disposed before the first Fourier transform unit 51. Further, the position of the fourth Fourier transform unit 54 disposed at the subsequent stage of the third Fourier transform unit 53 is not limited to this, and for example, the fourth Fourier transform unit 54 disposed at the subsequent stage of the first Fourier transform unit 51 and It may be disposed between the third Fourier transform unit 53 or may be disposed before the first Fourier transform unit 51. An image g (ξ, η) of the object 2 is obtained by performing computation on the signal s ₂ (u ′, t) using such a computation unit 50.

(Third arrangement example)
Next, a third arrangement example will be described. In the third arrangement example, the lens configuration shown in FIG. 19 is used. As shown in FIG. 19, in the third arrangement example, the beam splitter 12 is arranged on the rear focal plane of the lens 405 so as to divide substantially zero-order light into two. The light reflected by the beam splitter 12 is input to the lens 60 as the second light. In the third arrangement example, the light receiving surface of the photodetector 46 is arranged on the u "v" plane which is an arbitrary surface perpendicular to the optical axis of the front stage or the rear stage of the lens 40 in both the first direction and the second direction. The This u "v" plane is treated as a Fresnel diffraction plane. The Fresnel diffraction image g "(u", v ") of the complex amplitude image g (ξ, η) of the object 2 is expressed by the following equation (17). H in this equation (17) is the following (18) H is the Fourier transform of h, G is the Fourier transform of the complex amplitude image g (ξ, η) of the object 2. FT ⁻¹ is a symbol representing the computation of the two-dimensional inverse Fourier transform The variable z in the equation is the distance (distance) between the ξη plane and the u "v" plane, k is the wave number, and λ is the wavelength.

  This equation (17) indicates that an inverse Fourier transform image g "(u", v ") appears on the u" v "plane, which is obtained by multiplying G (u, v) on the uv plane by H (u, v). In other words, the equation (17) is obtained by multiplying G by H when Fourier transforming an image g ″ (u ″, v ″) appearing on the u ″ v ″ plane. It means that.

Accordingly, when a signal representing the sum of signals on a straight line parallel to the v "direction for an arbitrary u _n " on the u "v" plane is represented as s ₃ (u ", t), the following equation (19) is obtained. As shown, the signal s ₃ (u ″, t) is multiplied by H (u) by G (u, v) in the uv plane by performing a Fourier transform on the variable u ″ and the time variable t. Is obtained.

  Here, H (u) represents a function that is uniform in the v direction among the functions H obtained by the two-dimensional Fourier transform of equation (18). The u "direction will be described in detail. The Fourier transform relating to the variable u" by the arithmetic unit 50 is the same as the optical Fourier transform in which the lens 40 in FIG. 1 is arranged, and is represented by d ≠ f in the equation (10). Get the distribution. On the other hand, for the v ″ direction, the same distribution as v in the first arrangement example is obtained for the reason described above.

  In order to obtain G (u, v) in the uv plane from the above equation (19), it may be divided by H (u) as in the following equation (20). Thereafter, a complex amplitude image g (ξ, η) of the object 2 can be obtained by performing the same arithmetic processing as in the first arrangement example.

In the configuration of the observation apparatus 1 of the present embodiment, in the third arrangement example in which the light receiving surface of the photodetector 46 is arranged on an arbitrary u "v" plane perpendicular to the optical axis at the front stage or the rear stage of the lens 40, the arithmetic unit 50 obtains an image of the object 2 by performing the arithmetic processing as described above. That is, the operation unit 50, u "v""signal s ₃ to and time t as a variable (u" position u on the plane, t) to obtain data, the signal s ₃ of (u ", t) Fourier transform is performed on the data with respect to the variable u ″ and the time variable t (the above equation (19)), and the data obtained by this Fourier transform is divided by H to obtain G on the uv plane (the above equation (20)). Of the data G obtained in this way, data in a region including the Nyquist frequency f _nyq around the frequency Ω is extracted (the above equation (14)), and the two-dimensional Fourier transform is performed on the extracted data (the above ( 15) Obtain an image g (ξ, η) of the object 2). In order to obtain a focused complex amplitude image g (ξ, η), it is necessary to appropriately correct the initial phase according to the optical conditions of the reference light and the scattered light.

FIG. 20 is a diagram illustrating a configuration of the light detection unit 46 and the calculation unit 50 in the third arrangement example in which the calculation processing as described above is performed. The computing unit 50 includes a first Fourier transform unit 51, a second Fourier transform unit 52, a fourth Fourier transform unit 54, a specific region cutout unit 55, and a secondary phase division unit 57. The second Fourier transform unit 52 includes a third Fourier transform unit 53 and a fourth Fourier transform unit 54. The first Fourier transform unit 51 performs a Fourier transform on the time variable t with respect to the data of the signal s ₃ (u ″, t) with the position u ″ on the u ″ v ″ plane and the time t as variables (the above equation (19) Fourier transform for time variable t) is performed. The fourth Fourier transform unit 54 arranged at the subsequent stage of the first Fourier transform unit 51 performs a Fourier transform on the variable u ″ (Fourier transform on the variable u ″ in the above equation (19)) for the data obtained by the Fourier transform. Do. The secondary phase division unit 57 divides the data obtained by the fourth Fourier transform unit 54 by H to obtain G on the uv plane (the above equation (20)). The specific area cutout section 55 _cuts out data of an area including the Nyquist frequency f _nyq around the frequency Ω from the data G obtained in this way (the above equation (14)). Third Fourier transform unit 53 performs this extracted data one-dimensional Fourier transform with respect to time-frequency omega _d (Fourier transform with respect to time-frequency omega _d above (15)). The fourth Fourier transform unit 54 arranged at the subsequent stage of the third Fourier transform unit 53 performs Fourier transform related to the variable u (Fourier transform related to the variable u in the equation (15)). Focusing on the Fourier transform unit, in the third arrangement example, the calculation unit 50 is disposed in the order of the first Fourier transform unit 51, the fourth Fourier transform unit 54, the third Fourier transform unit 53, and the fourth Fourier transform unit 54. In addition, the position of the 4th Fourier-transform part 54 arrange | positioned at the back | latter stage of the 1st Fourier-transform part 51 is not restricted to this, For example, it is arrange | positioned at the back | latter stage of the 3rd Fourier-transform part 53 and the 3rd Fourier-transform part 53. It may be disposed between the fourth Fourier transform unit 54 or may be disposed before the first Fourier transform unit 51. Further, the position of the fourth Fourier transform unit 54 disposed at the subsequent stage of the third Fourier transform unit 53 is not limited to this, and for example, the fourth Fourier transform unit 54 disposed at the subsequent stage of the first Fourier transform unit 51 and It may be disposed between the third Fourier transform unit 53 or may be disposed before the first Fourier transform unit 51. An image g (ξ, η) of the object 2 is obtained by performing computation on the signal s ₃ (u ″, t) using such a computation unit 50.

  The special case of the third arrangement example corresponds to the first arrangement example or the second arrangement example. That is, the second arrangement example corresponds to the case where H (u, v) = 1 in the expression (17) of the third arrangement example. The first arrangement example corresponds to the case where the Fourier plane (Franphophor diffraction) is the u "v" plane in the third arrangement example. The latter will be described below.

  When the expression (18) is substituted into the expression (17) and developed, the following expression (21) is obtained. In this equation (21), if z is infinite, the value of the exponential function in the integral on the right side is approximated to 1, and equation (21) is approximated to the following equation (22). This expression (22) is equivalent to the expression (10). Therefore, the special case of the third arrangement example, that is, the case of d = f in the equation (10) is the first arrangement example.

(Fourth arrangement example)
In the first arrangement example, the second arrangement example, and the third arrangement example described above, the calculation contents have been described by omitting the initial phase φ ₀ resulting from the optical conditions of the fluorescent scattered light and the reference light. Similar to the first arrangement example, the light receiving surface of the photodetector 46 is a rear focal plane in the first direction of the lens 40 and is arranged so as to coincide with the rear focal plane of the lens 40 in the second direction. 1, the configuration in which the calculation unit 50 corrects the initial phase φ ₀ included in the data obtained by the one-dimensional Fourier transform relating to the time variable will be described in detail below as a fourth arrangement example. The lens 40 in the fourth arrangement example has the same lens configuration as the lens 40 in the first arrangement example shown in FIG.

21, when the observation device 1 of this embodiment adopts the fourth arrangement example, the signal s ₄ (u _n representing the sum of signal h ₁ to h _N on v parallel to the direction line for each u _n , t) is a diagram schematically showing an operation of obtaining t). In FIG. 21, symbol Σ indicates an operation for obtaining the sum of the signals h _{1 to} h _N. A signal s ₄ (u, t) representing the sum of signals h (v) on a straight line parallel to the v direction with respect to an arbitrary u coordinate value is expressed by equation (11).

In the first arrangement example, the initial phase φ ₀ is omitted and the equation (13) is derived. However, when the initial phase φ ₀ is taken into consideration, the signal s ₄ (u, t) regarding the position u on the uv plane and the time variable t. 1-dimensional Fourier transform of is calculated by the same calculation as s ₁ is represented by the following expression (23) _(u, t).

When the left side of the equation (23) is expressed as S ₄ (u, Δv + v), the right side of the equation (23) is obtained by multiplying both sides of the equation (23) by the term exp (−iφ ₀ ) including the initial phase φ _0. Only the proportionality constant a and the function G are provided, and the right side of the equation (13). That is, the correction of the initial phase φ ₀ is equivalent to multiplying the signal S ₄ (u, Δv + v) by exp (−iφ ₀ ).

Thus, by multiplying the signal S ₄ (u, Δv + v) by exp (−iφ ₀ ), the two-dimensional Fourier transform image G (u) for the complex amplitude image g (ξ, η) of the fluorescence from the object 2 is obtained. , Δv + v). Since the Fourier transform image G (u, Δv + v) is the same as that in the first arrangement example, the complex amplitude image g of the object 2 is obtained by performing the same arithmetic processing as in the first arrangement example. (ξ, η) can be obtained.

In the configuration of the observation apparatus 1 according to the present embodiment, in the fourth arrangement example in which the light receiving surface of the photodetector 46 is arranged on the back focal plane (uv plane) of the lens 40, the calculation unit 50 performs the calculation process as described above. Go to get an image of the object 2. That is, the arithmetic unit 50 acquires data of a signal s ₄ (u, t) whose variables are the position u on the uv plane and the time t, and the time variable for the data of this signal s ₄ (u, t). Perform one-dimensional Fourier transform on t (Equation (23) above), correct the data obtained by this one-dimensional Fourier transform with the initial phase φ ₀ , and center the frequency Ω in the data G obtained by this correction As described above, the data of the region including the Nyquist frequency f _nyq is cut out (the above equation (14)), the two-dimensional Fourier transform is performed on the cut out data (the above equation (15)), and the image g (ξ , η).

FIG. 22 is a diagram illustrating a configuration of the calculation unit 50 in the fourth arrangement example that performs the calculation processing as described above. That is, the arithmetic unit 50 performs a first dimensional Fourier transform (the above equation (23)) on the time variable t with respect to the data of the signal s ₄ (u, t) having the position u on the uv plane and the time t as variables. A Fourier transform unit 51, an initial phase corrector 56 for correcting the data obtained by the one-dimensional Fourier transform with an initial phase φ ₀ , and a Nyquist frequency f _nyq around the frequency Ω of the corrected data G. The specific region cutout unit 55 that cuts out the data of the region included in (Expression (14)) above, and the one-dimensional Fourier transform relating to the time frequency ω _d (Fourier transform relating to the time frequency ω _d of Equation (15) above) ) And a fourth Fourier transform unit 5 for performing a Fourier transform on the variable u (Fourier transform on the variable u in the above equation (15)). Provided with a door. Focusing on the Fourier transform unit, in the fourth arrangement example, the calculation unit 50 is disposed in the order of the first Fourier transform unit 51, the third Fourier transform unit 53, and the fourth Fourier transform unit 54. The position of the fourth Fourier transform unit 54 is not limited to this. For example, the fourth Fourier transform unit 54 may be arranged between the first Fourier transform unit 51 and the third Fourier transform unit 53, or the position of the first Fourier transform unit 51 It may be arranged in front. An image g (ξ, η) of the object 2 is obtained by performing computation on the signal s ₁ (u, t) using such a computation unit 50.

As shown in the fourth arrangement example, blurring of the complex amplitude image g (ξ, η) due to the initial phase φ ₀ is prevented by correcting the initial phase φ _{0 according} to the optical conditions of the reference light and the scattered light. And a focused complex amplitude image g (ξ, η) can be obtained. The correction process for the initial phase φ ₀ has been described by way of an example of the arrangement in which the light receiving surface of the photodetector 46 is arranged so as to coincide with the rear focal plane of the lens 40. correction of the initial phase phi ₀ can be performed by. In the arrangement example shown below, an example in which the initial phase φ ₀ is corrected is shown, but the correction process for the initial phase φ ₀ is not necessarily required.

(Fifth arrangement example)
In the second arrangement example described above, the calculation unit 50 is arranged in the order of the first Fourier transform unit 51, the fourth Fourier transform unit 54, the third Fourier transform unit 53, and the fourth Fourier transform unit 54. Similar to the second arrangement example, the light receiving surface of the photodetector 46 is an imaging surface on which an image of the object is formed in the first direction by the lens 40, and an image of the object is formed in the second direction. In the observation apparatus 1 arranged on the imaging plane (u′v ′ plane), a configuration in which the calculation unit 50 is simplified will be described below as a fifth arrangement example and compared with the second arrangement example. The lens 40 in the fifth arrangement example has the same lens configuration as the lens 40 in the second arrangement example shown in FIG.

  17 represents the back focal plane of the lens 403. In the second arrangement example, the light receiving surface of the photodetector 46 is arranged on the rear focal plane of the lens 404 having the front focal plane on the uv plane. In FIG. 17, X is the first direction, which is the same direction as u ′. Y is the second direction and coincides with v ′. Z is a direction orthogonal to the first direction and the second direction. The lens 403 and the lens 404 are spherical lenses and exhibit the same action in the XY direction. Since the X direction and the Y direction are orthogonal to each other, the Fourier transform in the X direction and the Fourier transform in the Y direction do not affect each other, and there is no mathematical problem even if they are considered independently.

In FIG. 17, the action of the lens 404 in the second arrangement example corresponds to optically performing a one-dimensional Fourier transform on the variable u and performing a one-dimensional Fourier transform on the variable v on the image appearing on the uv plane. . Further, the calculation unit 50 in the second arrangement example obtains G (u, Ω + ω _d ) by performing the first two-dimensional Fourier transform on the signal s ₂ (u ′, t) according to the equation (16). The first two-dimensional Fourier transform corresponds to performing a one-dimensional Fourier transform on the time variable t and performing a one-dimensional Fourier transform on the variable u ′.

Further, in the calculation unit 50 in the second arrangement example, for G (u, Ω + ω _d ), a distribution G (u, ω _d ) obtained by cutting out a frequency region including Nyquist frequency f _nyq before and after Ω as a center frequency. A second two-dimensional inverse Fourier transform is performed to obtain g (u ′, t). The second two-dimensional Fourier transform, performs one-dimensional Fourier transform with respect to time-frequency omega _d, corresponding to that obtained by one-dimensional Fourier transform with respect to the variable u. That is, the calculation unit 50 in the second arrangement example performs a one-dimensional Fourier transform related to the variable u ′ in the first two-dimensional Fourier transform and a one-dimensional Fourier transform related to the variable u in the second two-dimensional Fourier transform. , U ′ direction is not subjected to Fourier transform. Therefore, in the second arrangement example, it can be said that there is a redundancy of Fourier transform in the u direction or the u ′ direction (first direction) in the calculation unit 50 that inputs the output of the light detection unit 46.

FIG. 23 shows a schematic diagram of the calculation by the calculation unit 50 of the fifth arrangement example in which the second arrangement example is simplified and the number of Fourier transforms is reduced. In the observation apparatus 1, the light receiving surface of the photodetector 46 is an image formation surface on which an image of the object 2 is formed in the first direction by the lens 404, and an image formation on which an image of the object 2 is formed in the second direction. In the fifth arrangement example arranged on the plane (u′v ′ plane), the calculation unit 50 obtains an image of the object 2 by performing the following calculation process. That is, the lens 404 constituting the lens 40 optically performs a Fourier transform in the first direction. The calculation unit 50 acquires data of the signal s ₅ (u ′, t) having the position u on the uv plane and the time t as variables, and the data of the signal s ₅ (u ′, t) is related to the time variable t. One-dimensional Fourier transform is performed (the above equation (23)). The data obtained in this one-dimensional Fourier transform is corrected by the initial phase phi _0, cut out data of the area including the back and forth Nyquist frequency f _NYQ around the frequency Ω of the correction to the data obtained G (the (14) Formula). This extracted data by performing a one-dimensional Fourier transform with respect to time-frequency omega _d (Fourier transform with respect to time-frequency omega _d above (15)), the image g (xi], eta) of the object 2 obtained.

FIG. 24 is a diagram illustrating a configuration of the calculation unit 50 in the fifth arrangement example that performs the calculation processing as described above. That is, the calculation unit 50 includes a lens 40, a first Fourier transform unit 51, a third Fourier transform unit 53, an initial phase corrector 56, and a specific region cutout unit 55. The lens 404 optically Fourier-transforms the Franforfer diffraction image of the object 2 formed on the rear focal plane of the lens 403. The first Fourier transform unit 51 performs one-dimensional Fourier transform on the time variable t (Fourier transform on the time variable t in the above equation (16)) for the data S ₅ (u ′, ω) obtained by the Fourier transform. Initial phase corrector 56 corrects the data obtained in this one-dimensional Fourier transform in the initial phase phi _0. The specific area cutout section 55 _cuts out data of an area including the Nyquist frequency f _nyq around the frequency Ω from the corrected data G (the above equation (14)). Third Fourier transform unit 53 performs this extracted data one-dimensional Fourier transform with respect to time-frequency omega _d (Fourier transform with respect to time-frequency omega of the equation (15)). Focusing on the Fourier transform unit, in the fifth arrangement example, the calculation unit 50 is disposed in the order of the lens 404, the first Fourier transform unit 51, and the third Fourier transform unit 53. An image g (ξ, η) of the object 2 is obtained by performing computation on the signal s ₅ (u ′, t) using such a computation unit 50. A Franforfer diffraction image appears on the rear focal plane of the lens 403. Further, the lens 404 performs Fourier transform, and an image is formed on the light receiving surface of the photodetector 46. That is, since the lens 404 optically performs Fourier transform in the first direction and the second direction, the action of Fourier transform in the first direction is included. Comparing with the calculation unit of the first arrangement example, the fifth arrangement example corresponds to optically performing the fourth Fourier transform unit 54 in the calculation unit of the first arrangement example by the lens 404.

(Sixth arrangement example)
Similarly to the third arrangement example, the light receiving surface of the photodetector 46 is a u "v" plane (an arbitrary surface perpendicular to the optical axis of the front stage or the rear stage of the lens 40 in both the first direction and the second direction of the lens 40 ( In the observation apparatus 1 arranged on the surface on which the Fresnel diffraction image of the object is formed), a configuration in which the arrangement order of the computing units of the computing unit 50 in the third arrangement example is changed will be described below as a sixth arrangement example. The lens 40 in the sixth arrangement example has the same lens configuration as the lens 40 in the third arrangement example shown in FIG.

The arithmetic unit 50 in the third arrangement example performs the first two-dimensional Fourier transform on the signal s ₃ (u ″, t) output from the photodetector 46 and G (u, Ω + ω _d ) as shown in the equation (19). H (u) is obtained, and this first two-dimensional Fourier transform corresponds to performing a one-dimensional Fourier transform on the time variable t and performing a one-dimensional Fourier transform on the variable u ″. The calculation unit 50 in the third arrangement example has a distribution G (u, ω) obtained by cutting out a frequency region including the Nyquist frequency f _nyq before and after the obtained G (u, Ω + ω _d ) H (u) with Ω as a center frequency. _d ) After dividing H (u) by the secondary phase H (u), a second two-dimensional inverse Fourier transform is performed to obtain g (ξ, η). The operation of this second two-dimensional Fourier transform, performs one-dimensional Fourier transform with respect to time-frequency omega _d, corresponding to that obtained by one-dimensional Fourier transform with respect to the variable u.

  Focusing on the calculation in the first direction (u "direction and u direction) among the above calculations, a one-dimensional Fourier transform on the variable u" and a division operation (secondary phase division) divided by the secondary phase H (u) Part 57) and the order of the one-dimensional Fourier transform with respect to the variable u. Hereinafter, the calculations for calculating the first direction are collectively referred to as a secondary phase corrector 60.

  The calculation unit 50 in the third arrangement example is equivalent to a configuration in which the secondary phase division unit 57 is added to the calculation unit 50 in the second arrangement example. The calculation unit 50 in the third arrangement example is equivalent to a configuration in which the secondary phase corrector 60 is added to the calculation unit 50 in the fifth arrangement example.

  In the sixth embodiment, as in the third embodiment, a lens 40 including an objective lens 405 and a lens 406 as shown in FIG. 19 is used as the lens 40, and the light detection unit 46 has the first direction and the first direction. It is arranged on an arbitrary plane perpendicular to the optical axis of the front stage or the rear stage in two directions.

A schematic diagram of the calculation by the calculation unit 50 of the sixth arrangement example is shown in FIG. In the sixth arrangement example, the same lens 40 as in the third arrangement example is provided, and the secondary phase corrector 60 is arranged at the subsequent stage of the calculation unit 50 in the fifth arrangement example. That is, in the sixth arrangement example, the calculation unit 50 obtains an image of the object 2 by performing the following calculation process. That is, the operation unit 50, u "v""signal s ₆ a and time t as a variable (u" position u on the plane, t) to obtain data, the signal s ₆ of (u ", t) The data is subjected to Fourier transformation with respect to the time variable t (Fourier transformation with respect to the time constant t in the above equation (19)), and the data obtained by the one-dimensional Fourier transformation is corrected with the initial phase φ ₀ and obtained by this correction. In the data G, data in a region including the Nyquist frequency f _nyq around the frequency Ω is extracted (the above equation (14)), and the one-dimensional Fourier transform is performed with respect to the time frequency ω _d (the above (15)). Fourier transform with respect to the time frequency ω of the equation), and one-dimensional Fourier transformation (various u ”with respect to the constant u ″ in the above equation (19)) with respect to the variable u ″ for the data obtained by this Fourier transformation And G in the uv plane is obtained by dividing by H (the above equation (20)), and the data obtained thereby is subjected to a one-dimensional Fourier transform with respect to the variable u (the Fourier transform regarding the variable u in the above equation (15)). By doing so, an image g (ξ, η) of the object 2 is obtained.

  As described above, in the sixth arrangement example, the two-dimensional Fourier transform of the second arrangement example is decomposed into one-dimensional Fourier transforms in the first direction and the other directions, and those one-dimensional Fourier transforms are rearranged. The mathematical calculation method is the same as in the third arrangement example. Note that the secondary phase corrector 60 shows the action in the first direction of the lens 404 in the second arrangement example together with the action in the first direction of the lens 406 constituting the lens 40 in the third arrangement example. Therefore, in the sixth arrangement example, the configuration in which the lens 406 and the secondary phase corrector 60 are removed and the light receiving surface of the photodetector 46 is arranged on the uv plane is the first arrangement example.

FIG. 26 is a diagram illustrating a configuration of the calculation unit 50 in the sixth arrangement example that performs the calculation processing as described above. The computing unit 50 includes a first Fourier transform unit 51, a second Fourier transform unit 52, a specific region cutout unit 55, an initial phase corrector 56, and a secondary phase division unit 57. The second Fourier transform unit 52 includes a third Fourier transform unit 53 and two fourth Fourier transform units 54. The first Fourier transform unit 51 performs one-dimensional Fourier transform on the time variable t with respect to the data of the signal s ₆ (u ″, t) having the time t on the u ″ v ”plane as a variable (the time variable of the above equation (19)). The initial phase corrector 56 corrects the data obtained by the one-dimensional Fourier transform with the initial phase φ _{0. The} specific area cutout unit 55 selects the frequency of the corrected data. The data of the region including the Nyquist frequency f _nyq before and after is centered around Ω (the above equation (14)), and the third Fourier transform unit 53 performs a one-dimensional Fourier transform on the time frequency ω _d (the above ( 15) Fourier transform related to the time frequency ω in the equation (4) The fourth Fourier transform unit 54 arranged after the third Fourier transform unit 53 is a one-dimensional Fourier transform related to the variable u ″. (Fourier transformation related to the variable u ″ in the above equation (19)). The secondary phase division unit 57 divides the Fourier transformed data by the secondary phase H (u) (the above equation (20)). The fourth Fourier transform unit 54 disposed after the secondary phase division unit 57 performs one-dimensional Fourier transform on the variable u (Fourier transform on the variable u in the above equation (15)). In the sixth arrangement example, the calculation unit 50 is arranged in the order of the first Fourier transform unit 51, the third Fourier transform unit 53, the fourth Fourier transform unit 54, and the fourth Fourier transform unit 54. The third Fourier transform unit. The position of the fourth Fourier transform unit 54 disposed at the subsequent stage of 53 is not limited to this, and may be disposed, for example, between the first Fourier transform unit 51 and the third Fourier transform unit 53, or the first Fourier transform The position of the fourth Fourier transform unit 54 disposed after the fourth Fourier transform unit 54 is not limited to this, for example, the first Fourier transform unit 51 and the third Fourier transform unit 51 may be disposed before the first Fourier transform unit 54. It may be arranged between the Fourier transform unit 53 or may be disposed before the first Fourier transform unit 51. The calculation unit 50 uses such a calculator to calculate the signal s ₆ (u ", An image g (ξ, η) of the object 2 is obtained by performing an operation on t).

  In the observation apparatus 1 of the present embodiment, the lens 40 provided between the object 2 and the photodetector 46 has the same effect on the scattered light in the x and y directions in the above description. there were. However, the optical system between the object 2 and the photodetector 46 may enlarge or reduce the Fourier plane by a relay optical system having a flat magnification.

(Seventh arrangement example)
Next, a seventh arrangement example will be described. The seventh arrangement example is different from the first arrangement example in the configuration of the lens 40, and is otherwise the same as the first arrangement example. In the seventh arrangement example, the light receiving surface of the light detection unit 46 is a surface on which the franphophor diffraction image of the object 2 is formed in the x direction (first direction) by the lens 40 and is in the y direction (second direction). ) Is arranged on the surface on which the Franforfer diffraction image of the object 2 is formed. The lens 40 of the seventh arrangement example is arranged between the object 2 and the light detection unit 46.

  FIG. 27 shows details of the lens 40 in the seventh arrangement example. In the seventh arrangement example, the lens 40 is configured by three lenses obtained by adding the lens LS2 to the lens 40 in the second arrangement example including the lens 403 and the lens 404. The three lenses constituting the lens 40 are spherical lenses. In the image forming action by the lens, these spherical lenses exhibit the same action in the x and y directions. The beam splitter 12 is arranged on the rear focal plane of the lens 403 constituting the lens 40 so as to divide substantially zero-order light into two. The light reflected by the beam splitter 12 is input to the lens 60 as the second light.

  The lens 40 in the second arrangement example forms an object image on the surface IP. In both the x and y directions, the image of the object 2 is once formed on the surface IP by the lenses 403 and 404. The front focal plane of the lens LS2 coincides with the plane IP. Further, the rear focal plane of the lens LS2 coincides with the light receiving surface of the photodetector 46. In this way, a franphophor diffraction image of the object 2 is formed on the light receiving surface of the photodetector 46 in both the lens x direction and the y direction.

  Next, a method for processing a signal obtained by the photodetector 46 using such a lens 40 will be described. The coordinate system on the light receiving surface of the photodetector 46 is the uv plane as in the first arrangement example. In the first arrangement example, the Francophor diffraction image appeared on the uv plane in the u and v directions. In the seventh arrangement example, Franforfer diffraction images appear in the u and v directions. That is, the seventh arrangement example is different from the first arrangement example in the configuration of the lens 40.

A signal representing the sum of signals on a straight line parallel to the v direction is defined as s ₇ (u, t). The arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₇ (u, t) output from the light detection unit 46 and the arithmetic unit configuration for performing this processing were obtained in the first arrangement example. This is the same as the arithmetic processing for obtaining the complex amplitude image g (ξ, η) of the object 2 based on s ₁ (u, t) and the arithmetic unit configuration for performing this processing. Therefore, the description of the arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₇ (u, t) output from the light detection unit 46 and the arithmetic unit configuration that performs this processing is omitted.

(Eighth arrangement example)
Next, an eighth arrangement example will be described. The eighth arrangement example is different from the first arrangement example in the configuration of the lens 40, and is otherwise the same as the first arrangement example. In the eighth arrangement example, the light receiving surface of the light detection unit 46 is a surface on which a franphophor diffraction image of the object 2 is formed in the x direction (first direction) by the lens 40 and is in the y direction (second direction). ) In the imaging plane where the image of the object 2 is formed. The lens 40 of the eighth arrangement example is arranged between the object 2 and the light detection unit 46.

FIG. 28 shows details of the lens 40 in the eighth arrangement example. In the eighth arrangement example, the lens 40 is configured by five lenses in which the lenses LS1, LS2, and LS3 are added to the lens 40 in the second arrangement example including the lens 403 and the lens 404. Of the five lenses constituting the lens 40, 403 and 404 are spherical lenses, and LS1, LS2, and LS3 are cylindrical lenses. In the image forming action by the lens, different actions are shown in the x and y directions by these cylindrical lenses. Note that the focal lengths of the lenses LS1, LS2, and LS3 are f _LS1 , f _LS2 , and f _LS3 , respectively. These focal lengths have a relationship of f _LS1 = f _LS3 , f _LS2 = 2f _LS1 = 2f _LS3 . The beam splitter 12 is arranged on the rear focal plane of the lens 403 constituting the lens 40 so as to divide substantially zero-order light into two. The light reflected by the beam splitter 12 is input to the lens 60 as the second light.

  That is, the lens LS1 and the lens LS3 do not contribute to image formation because they do not have a curvature shape in the x direction. Therefore, in the x direction, this is equivalent to a configuration in which only the lenses 403, 404, and LS2 are arranged as shown in the upper part of FIG. On the other hand, the lens LS2 does not contribute to image formation because it does not have a curvature shape in the y direction. Accordingly, in the y direction, this is equivalent to a configuration in which only lenses 403, 404, LS1 and LS3 are arranged as shown in the lower part of FIG.

  In the x direction, the image of the object 2 is once formed on the surface IP by the lenses 403 and 404. Next, a Francophor diffraction image of the image is formed on the light receiving surface by the same action as the seventh arrangement example of the lens LS2. On the other hand, in the y direction, an image of the object 2 is once formed on the surface IP by the lenses 403 and 404. The lenses LS1 and LS3 constitute a so-called 4f optical system. The 4f optical system is an optical system in which the rear focal plane of LS1 coincides with the front focal plane of LS3, and an image of the front focal plane of LS1 is formed on the rear focal plane of LS3. As described above, the lens 40 in the eighth arrangement example forms a franphophor diffraction image of the object 2 in the x direction and an image of the object 2 in the y direction on the light receiving surface of the photodetector 46.

Next, a method for processing a signal obtained by the photodetector 46 using such a lens 40 will be described. The coordinate system on the light receiving surface of the photodetector 46 is the uv plane as in the first arrangement example. In the first arrangement example, a Francophor diffraction image appears on the uv plane in the u and v directions. In the eighth arrangement example, a Franforfer diffraction image appears in the u direction, and an object image appears in the v direction. A signal representing the sum of signals on a straight line parallel to the v direction is defined as s ₈ (u, t). The arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₈ (u, t) output from the light detection unit 46 and the arithmetic unit configuration for performing this processing were obtained in the first arrangement example. This is the same as the arithmetic processing for obtaining the complex amplitude image g (ξ, η) of the object 2 based on s ₁ (u, t) and the arithmetic unit configuration for performing this processing. Therefore, the description of the arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₈ (u, t) output from the light detection unit 46 and the arithmetic unit configuration that performs this processing is omitted.

(Ninth arrangement example)
Next, a ninth arrangement example will be described. The ninth arrangement example is different from the first arrangement example in the configuration of the lens 40, and is otherwise the same as the first arrangement example. In the ninth arrangement example, the light receiving surface of the light detection unit 46 is a surface on which the franphophor diffraction image of the object 2 is formed in the x direction (first direction) by the lens 40 and is in the y direction (second direction). ) On the surface where the Fresnel diffraction image of the object is formed. The lens 40 of the ninth arrangement example is arranged between the object 2 and the light detection unit 46.

  FIG. 29 shows details of the lens 40 in the ninth arrangement example. In the ninth arrangement example, the lens 40 is configured by five lenses in which the lenses LS1, LS2, and LS3 are added to the lens 40 in the second arrangement example including the lens 403 and the lens 404. Of the five lenses constituting the lens 40, 403 and 404 are spherical lenses, and LS1, LS2, and LS3 are cylindrical lenses. In the image forming action by the lens, different actions are shown in the x and y directions by these cylindrical lenses. The beam splitter 12 is arranged on the rear focal plane of the lens 403 constituting the lens 40 so as to divide substantially zero-order light into two. The light reflected by the beam splitter 12 is input to the lens 60 as the second light.

  That is, the lens LS1 and the lens LS3 do not contribute to image formation because they do not have a curvature shape in the x direction. Therefore, in the x direction, this is equivalent to a configuration in which only lenses 403, 404, and LS2 are arranged as shown in the upper part of FIG. On the other hand, in the y direction, the lens LS2 does not contribute to image formation because it does not have a curvature shape. Therefore, in the y direction, this is equivalent to a configuration in which only lenses 403, 404, LS1 and LS3 are arranged as shown in the lower part of FIG.

  In the x direction, the image of the object 2 is once formed on the surface IP by the lenses 403 and 404. Next, a Francophor diffraction image of the image is formed on the light receiving surface of the light detection unit 46 by the same operation as the seventh arrangement example of the lens LS2. On the other hand, the image of the object 2 is once formed on the surface IP by the lenses 403 and 404 in the y direction. The lenses LS1 and LS3 do not have a so-called 4f optical system configuration. That is, as shown in the lower part of FIG. 29, the front focal plane of LS3 does not coincide with the rear focal plane of LS1. Therefore, an image of the object 2 or a Fourier image is not formed on the light receiving surface of the light detection unit 46. As described above, the lens 40 forms a franphofer diffraction image of the object 2 in the x direction and a Fresnel diffraction image of the object 2 in the y direction on the light receiving surface of the photodetector 46.

Next, a method for processing a signal obtained by the photodetector 46 using such a lens 40 will be described. The coordinate system on the light receiving surface of the photodetector 46 is set to the uv plane as in the first arrangement example. In the first arrangement example, a Francophor diffraction image appears on the uv plane in the u and v directions. In the ninth arrangement example, a Francophor diffraction image appears in the u direction, and a Fresnel diffraction image of the object appears in the v direction. A signal representing the sum of signals on a straight line parallel to the v direction is represented by s ₉ (u, t). The arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₉ (u, t) output from the light detection unit 46 and the arithmetic unit configuration for performing this processing were obtained in the first arrangement example. This is the same as the arithmetic processing for obtaining the complex amplitude image g (ξ, η) of the object 2 based on s ₁ (u, t) and the arithmetic unit configuration for performing this processing. Therefore, the description of the arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₉ (u, t) output from the light detection unit 46 and the arithmetic unit configuration that performs this processing is omitted.

(10th arrangement example)
Next, a tenth arrangement example will be described. The tenth arrangement example is different from the second or fifth arrangement example in the configuration of the lens 40, and is otherwise the same as the second or fifth arrangement example. In the tenth arrangement example, the light receiving surface of the light detection unit 46 is an imaging surface on which an image of the object 2 is formed in the x direction (first direction) by the lens 40, and in the y direction (second direction). The object 2 is disposed on the surface on which the Franforfer diffraction image is formed. The lens 40 of the tenth arrangement example is arranged between the object 2 and the light detection unit 46.

  FIG. 30 shows details of the lens 40 in the tenth arrangement example. In the tenth arrangement example, the lens 40 is constituted by five lenses obtained by adding the lenses LS1, LS2, and LS3 to the lens 40 in the second arrangement example constituted by the lens 403 and the lens 404. Of the five lenses constituting the lens 40, 403 and 404 are spherical lenses, and LS1, LS2, and LS3 are cylindrical lenses. In the image forming action by the lens, different actions are shown in the x and y directions by these cylindrical lenses. The beam splitter 12 is arranged on the rear focal plane of the lens 403 constituting the lens 40 so as to divide substantially zero-order light into two. The light reflected by the beam splitter 12 is input to the lens 60 as the second light.

  That is, the lens LS2 does not contribute to image formation because it does not have a curvature shape in the x direction. Therefore, the x direction is equivalent to a configuration in which only lenses 403, 404, LS1 and LS3 are arranged as shown in the upper part of FIG. On the other hand, the lens LS1 and the lens LS3 do not contribute to image formation because they do not have a curvature shape in the y direction. Accordingly, in the y direction, this is equivalent to a configuration in which only lenses 403, 404, and LS2 are arranged as shown in the lower part of FIG.

  In the x direction, the image of the object 2 is once formed on the surface IP by the lenses 403 and 404. The lenses LS1 and LS3 constitute a so-called 4f optical system. The 4f optical system is an optical system in which the rear focal plane of LS1 coincides with the front focal plane of LS3, and an image of the front focal plane of LS1 is formed on the rear focal plane of LS3. On the other hand, the image of the object 2 is once formed on the surface IP by the lenses 403 and 404 in the y direction. Next, a Fraunhofer diffraction image of the image is formed on the light receiving surface of the light detection unit 46 by the same action as the seventh arrangement example of the lens LS2. As described above, the lens 40 forms an image of the object 2 in the x direction and a franphophor diffraction image of the object 2 in the y direction on the light receiving surface of the photodetector 46.

Next, a method for processing a signal obtained by the photodetector 46 using such a lens 40 will be described. The coordinate system on the light receiving surface of the light detector 46 is the u′v ′ plane as in the second arrangement example. In the second or fifth arrangement example, the image of the object 2 appears on the u′v ′ plane in the u ′ and v ′ directions. In the tenth arrangement example, an image of the object 2 appears in the u ′ direction, and a Fraunhofer diffraction image of the object appears in the v ′ direction. A signal representing the sum of signals on a straight line parallel to the v ′ direction is defined as s ₁₀ (u ′, t). Arithmetic processing for obtaining a complex amplitude image g (ξ, η) based on s ₁₀ (u ′, t) output from the light detection unit 46 and the arithmetic unit configuration for performing this processing are the second and fifth arrangement examples. Same as the arithmetic processing for obtaining the complex amplitude image g (ξ, η) of the object 2 based on the obtained s ₂ (u ′, t) and s ₅ (u ′, t), and the arithmetic unit configuration for performing this processing. It is. That is, when the same configuration as the second arrangement example is adopted, the light source unit 10, the lens 40, the light detection unit 46, the first Fourier transform unit 51, the fourth Fourier transform unit 54, the third Fourier transform unit 53, the first The four Fourier transform units 54 are arranged in this order. When the same configuration as that of the fifth arrangement example is adopted, the light source unit 10, the lens 40, the light detection unit 46, the first Fourier transform unit 51, and the third Fourier transform unit 53 are arranged in this order. Therefore, the description of the arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₁₀ (u ′, t) output from the light detection unit 46 and the arithmetic unit configuration that performs this processing is omitted.

(Eleventh arrangement example)
Next, an eleventh arrangement example will be described. The eleventh arrangement example is different from the second or fifth arrangement example in the configuration of the lens 40, and is otherwise the same as the second or fifth arrangement example. In the eleventh arrangement example, the light receiving surface of the light detection unit 46 is an imaging surface on which an image of the object 2 is formed by the lens 40 in the x direction (first direction), and in the y direction (second direction). It arrange | positions in the imaging surface in which the image of the target object 2 is formed. The lens 40 of the twelfth arrangement example is arranged between the object 2 and the light detection unit 46.

  FIG. 31 shows details of the lens 40 in the eleventh arrangement example. In the eleventh arrangement example, the lens 40 is constituted by four lenses obtained by adding lenses LS1 and LS3 to the lens 40 used in the second arrangement example constituted by the lens 403 and the lens 404. The four lenses constituting the lens 40 are spherical lenses. In the image forming action by the lens, these spherical lenses exhibit the same action in both the x and y directions. The beam splitter 12 is arranged on the rear focal plane of the lens 403 constituting the lens 40 so as to divide substantially zero-order light into two. The light reflected by the beam splitter 12 is input to the lens 60 as the second light.

Therefore, the image of the object 2 is once formed on the surface IP by the lenses 403 and 404 in both the x direction and the y direction. The lenses LS1 and LS3 constitute a so-called 4f optical system. The 4f optical system is an optical system in which the rear focal plane of LS1 coincides with the front focal plane of LS3, and an image of the front focal plane of LS1 is formed on the rear focal plane of LS3.
Thus, the lens 40 forms an image of the object 2 in the x direction and an image of the object 2 in the y direction on the light receiving surface of the photodetector 46.

Next, a method for processing a signal obtained by the photodetector 46 using such a lens 40 will be described. The coordinate system on the light receiving surface of the photodetector 46 is the u′-v ′ plane as in the second arrangement example. In the second or fifth arrangement example, the image of the object 2 appears on the u′v ′ plane in the u ′ and v ′ directions. Similarly, in the eleventh arrangement example, the image of the object 2 appears on the u′v ′ plane in the u ′ and v ′ directions. That is, the tenth arrangement example is different from the second arrangement example in the configuration of the lens 40. A signal representing the sum of signals on a straight line parallel to the v ′ direction is defined as s ₁₁ (u ′, t). The arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₁₁ (u, t) output from the light detection unit 46 and the arithmetic unit configuration for performing this processing are obtained in the second and fifth arrangement examples. The arithmetic processing for obtaining the complex amplitude image g (ξ, η) of the object 2 based on the obtained s ₂ (u ′, t) and s ₅ (u ′, t) and the arithmetic unit configuration for performing this processing are the same. is there. That is, when the same configuration as the second arrangement example is adopted, the light source unit 10, the lens 40, the light detection unit 46, the first Fourier transform unit 51, the fourth Fourier transform unit 54, the third Fourier transform unit 53, the first The four Fourier transform units 54 are arranged in this order. When the same configuration as that of the fifth arrangement example is adopted, the light source unit 10, the lens 40, the light detection unit 46, the first Fourier transform unit 51, and the third Fourier transform unit 53 are arranged in this order. Therefore, the description of the arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₁₁ (u ′, t) output from the light detection unit 46 and the arithmetic unit configuration that performs this processing is omitted.

(Twelfth arrangement example)
Next, a twelfth arrangement example will be described. The twelfth arrangement example is different from the second or fifth arrangement example in the configuration of the lens 40, and is otherwise the same as the second or fifth arrangement example. In the twelfth arrangement example, the light receiving surface of the light detection unit 46 is an imaging surface on which an image of the object 2 is formed in the x direction (first direction) by the lens 40, and is in the y direction (second direction). Are arranged on the surface on which the Fresnel diffraction image of the object 2 is formed. The lens 40 of the twelfth arrangement example is arranged between the object 2 and the light detection unit 46.

  FIG. 32 shows details of the lens 40 in the twelfth arrangement example. In the twelfth arrangement example, the lens 40 is configured by five lenses in which the lenses LS1, LS2, and LS3 are added to the lens 40 used in the second arrangement example including the lens 403 and the lens 404. Of the five lenses constituting the lens 40, 403 and 404 are spherical lenses, and LS1, LS2, and LS3 are cylindrical lenses. In the image forming action by the lens, different actions are shown in the x and y directions by these cylindrical lenses. The beam splitter 12 is arranged on the rear focal plane of the lens 403 constituting the lens 40 so as to divide substantially zero-order light into two. The light reflected by the beam splitter 12 is input to the lens 60 as the second light.

  That is, the lens LS2 does not contribute to image formation because it does not have a curvature shape in the x direction. Therefore, in the x direction, this is equivalent to a configuration in which only lenses 403, 404, LS1, and LS3 are arranged as shown in the upper part of FIG. On the other hand, the lens LS1 and the lens LS3 do not contribute to image formation because they do not have a curvature shape in the y direction. Therefore, in the y direction, this is equivalent to a configuration in which only the lenses 403, 404, and LS2 are arranged as shown in the lower part of FIG.

  In the x direction, the image of the object 2 is once formed on the surface IP by the lenses 403 and 404. The lenses LS1 and LS3 constitute a so-called 4f optical system. The 4f optical system is an optical system in which the rear focal plane of LS1 coincides with the front focal plane of LS3, and an image of the front focal plane of LS1 is formed on the rear focal plane of LS3. On the other hand, in the y direction, an image of the object 2 is once formed on the surface IP by the lenses 403 and 404. Next, the front focal plane of the lens LS2 is different from the plane IP of the image of the object 2, and the rear focal plane of LS2 is different from the light receiving plane of the photodetector 46. Therefore, a Fresnel diffraction image of the image is formed on the light receiving surface. Thus, the lens 40 of the arrangement example 12 forms an image of the object 2 in the x direction and a Fresnel diffraction image of the object 2 on the light receiving surface of the photodetector 46 in the y direction.

Next, a method for processing a signal obtained by the photodetector 46 using such a lens 40 will be described. The coordinate system on the light receiving surface of the photodetector 46 is the u′v ′ plane as in the second or fifth arrangement example. In the second or fifth arrangement example, the image of the object 2 appears on the u′v ′ plane in the u ′ and v ′ directions. In the twelfth arrangement example, an image of the object 2 appears in the u ′ direction, and a Fresnel diffraction image of the object appears in the v ′ direction. A signal representing the sum of signals on a straight line parallel to the v ′ direction is defined as s ₁₂ (u ′, t). Arithmetic processing for obtaining a complex amplitude image g (ξ, η) based on s ₁₂ (u ′, t) output from the light detection unit 46 and the arithmetic unit configuration for performing this processing are the second and fifth arrangement examples. Same as the arithmetic processing for obtaining the complex amplitude image g (ξ, η) of the object 2 based on the obtained s ₂ (u ′, t) and s ₅ (u ′, t), and the arithmetic unit configuration for performing this processing. It is. That is, when the same configuration as the second arrangement example is adopted, the light source unit 10, the lens 40, the light detection unit 46, the first Fourier transform unit 51, the fourth Fourier transform unit 54, the third Fourier transform unit 53, the first The four Fourier transform units 54 are arranged in this order. When the same configuration as that of the fifth arrangement example is adopted, the light source unit 10, the lens 40, the light detection unit 46, the first Fourier transform unit 51, and the third Fourier transform unit 53 are arranged in this order. Therefore, the description of the arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₁₂ (u ′, t) output from the light detection unit 46 and the arithmetic unit configuration that performs this processing is omitted.

(13th arrangement example)
Next, a thirteenth arrangement example will be described. The thirteenth arrangement example is different from the third or sixth arrangement example in the configuration of the lens 40, and is otherwise the same as the third or sixth arrangement example. In the thirteenth arrangement example, the light receiving surface of the light detection unit 46 is a surface on which the Fresnel diffraction image of the object 2 is formed by the lens 40 in the x direction (first direction), and in the y direction (second direction). Are arranged on the surface on which the francforfer diffraction image of the object 2 is formed. The lens 40 in the thirteenth arrangement example is arranged between the object 2 and the light detection unit 46.

  FIG. 33 shows details of the lens 40 in the thirteenth arrangement example. In the thirteenth arrangement example, the lens 40 is configured by five lenses in which the lenses LS1, LS2, and LS3 are added to the lens 40 used in the second arrangement example including the lens 403 and the lens 404. Of the five lenses constituting the lens 40, 403 and 404 are spherical lenses, and LS1, LS2, and LS3 are cylindrical lenses. In the imaging action by the lens, different actions are shown in the x and y directions by these cylindrical lenses. The beam splitter 12 is arranged on the rear focal plane of the lens 403 constituting the lens 40 so as to divide substantially zero-order light into two. The light reflected by the beam splitter 12 is input to the lens 60 as the second light.

  That is, the lens LS2 does not contribute to image formation because it does not have a curvature shape in the x direction. Therefore, the x direction is equivalent to a configuration in which only lenses 403, 404, LS1, and LS3 are arranged as shown in the upper part of FIG. On the other hand, the lens LS1 and the lens LS3 do not contribute to image formation because they do not have a curvature shape in the y direction. Therefore, in the y direction, this is equivalent to a configuration in which only lenses 403, 404, and LS2 are arranged as shown in the lower part of FIG.

  In the x direction, the image of the object 2 is once formed on the surface IP by the lenses 403 and 404. The lenses LS1 and LS3 do not have a so-called 4f optical system configuration. That is, as shown in the upper part of FIG. 33, the front focal plane of LS3 does not coincide with the rear focal plane of LS1. Therefore, the image of the object 2 and the francophor diffraction image are not formed on the light receiving surface. On the other hand, in the y direction, an image of the object 2 is once formed on the surface IP by the lenses 403 and 404. Next, a Francophor diffraction image of the image is formed on the light receiving surface by the same action as the seventh arrangement example of the lens LS2. As described above, the lens 40 forms a Fresnel diffraction image of the object 2 in the x direction and a franphophor diffraction image of the object 2 in the y direction on the light receiving surface of the photodetector 46.

Next, a method for processing a signal obtained by the photodetector 46 using such a lens 40 will be described. The coordinate system on the light receiving surface of the photodetector 46 is the u "v" plane as in the third or sixth arrangement example. In the third or sixth arrangement example, the Fresnel diffraction image appears on the u "v" plane in the u "and v" directions. In the thirteenth arrangement example, a Fresnel diffraction image appears in the u ″ direction, and a Fraunhofer diffraction image of the object appears in the v direction. A signal representing the sum of signals on a straight line parallel to the v ″ direction is represented by s _13. (U ″, t). Arithmetic processing for obtaining a complex amplitude image g (ξ, η) based on s ₁₃ (u ″, t) output from the light detection unit 46 and an arithmetic unit configuration for performing this processing Is a calculation process for obtaining a complex amplitude image g (ξ, η) of the object 2 based on s ₃ (u ″, t) and s ₆ (u ″, t) obtained in the third and sixth arrangement examples. And it is the same as the arithmetic unit structure which performs this process. Therefore, the description of the arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₁₃ (u ″, t) output from the light detection unit 46 and the arithmetic unit configuration that performs this processing will be omitted.

(14th arrangement example)
Next, a fourteenth arrangement example will be described. The fourteenth arrangement example is different from the third or sixth arrangement example in the configuration of the lens 40, and is otherwise the same as the third or sixth arrangement example. In the fourteenth arrangement example, the light receiving surface of the light detection unit 46 is a surface on which the Fresnel diffraction image of the object 2 is formed by the lens 40 in the x direction (first direction), and the y direction (second direction). Are arranged on an imaging plane on which an image of the object 2 is formed. The lens 40 in the fourteenth arrangement example is arranged between the object 2 and the light detection unit 46.

  FIG. 34 shows details of the lens 40 in the fourteenth arrangement example. In the fourteenth arrangement example, the lens 40 is configured by five lenses in which the lenses LS1, LS2, and LS3 are added to the lens 40 used in the second arrangement example including the lens 403 and the lens 404. Of the five lenses constituting the lens 40, 403 and 404 are spherical lenses, and LS1, LS2, and LS3 are cylindrical lenses. In the image forming action by the lens, these cylindrical lenses exhibit different actions in the x direction and the y direction. The beam splitter 12 is arranged on the rear focal plane of the lens 403 constituting the lens 40 so as to divide substantially zero-order light into two. The light reflected by the beam splitter 12 is input to the lens 60 as the second light.

  That is, the lens LS1 and the lens LS3 do not contribute to image formation because they do not have a curvature shape in the x direction. Therefore, in the x direction, this is equivalent to a configuration in which only the lenses 403, 404, and LS2 are arranged as shown in the upper part of FIG. On the other hand, the lens LS2 does not contribute to image formation because it does not have a curvature shape in the y direction. Therefore, in the y direction, this is equivalent to a configuration in which only lenses 403, 404, LS1, and LS3 are arranged as shown in the lower part of FIG.

  In the x direction, the image of the object 2 is once formed on the surface IP by the lenses 403 and 404. Next, the front focal plane of the lens LS2 is different from the plane IP of the image of the object 2, and the rear focal plane of LS2 is different from the light receiving plane of the photodetector 46. Therefore, a Fresnel diffraction image of the image formed on the surface IP is formed on the light receiving surface. On the other hand, in the y direction, an image of the object 2 is once formed on the surface IP by the lenses 403 and 404. The lenses LS1 and LS3 constitute a so-called 4f optical system. The 4f optical system is an optical system in which the rear focal plane of LS1 coincides with the front focal plane of LS3, and an image of the front focal plane of LS1 is formed on the rear focal plane of LS3. Thus, the lens 40 forms a Fresnel diffraction image of the object 2 in the x direction and an image of the object 2 in the y direction on the light receiving surface of the photodetector 46.

Next, a method for processing a signal obtained by the photodetector 46 using such a lens 40 will be described. The coordinate system on the light receiving surface of the photodetector 46 is the u "v" plane as in the third or sixth arrangement example. In the third or sixth arrangement example, the Fresnel diffraction image appears on the u "v" plane in the u "and v" directions. In the fourteenth arrangement example, a Fresnel diffraction image appears in the u "direction, and an image of the object 2 appears in the v direction. A signal representing the sum of signals on a straight line parallel to the v" direction is represented by s ₁₄ (u " , T) The arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₁₄ (u ″, t) output from the light detection unit 46 and the arithmetic unit configuration for performing this processing are as follows. Calculation processing for obtaining a complex amplitude image g (ξ, η) of the object 2 based on s ₃ (u ″, t) and s ₆ (u ″, t) obtained in the ₃ , 6 arrangement example and this processing This is the same as the computing unit configuration to be performed. Therefore, the description of the arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₁₄ (u ″, t) output from the light detection unit 46 and the arithmetic unit configuration that performs this processing will be omitted.

(15th arrangement example)
Next, a fifteenth arrangement example will be described. The fifteenth arrangement example is different from the third or sixth arrangement example in the configuration of the lens 40, and is otherwise the same as the third or sixth arrangement example. In the fifteenth arrangement example, the light receiving surface of the light detection unit 46 is a surface on which the Fresnel diffraction image of the object 2 is formed by the lens 40 in the x direction (first direction), and in the y direction (second direction). It is arranged on the surface where the Fresnel diffraction image of the object is formed. The lens 40 in the fifteenth arrangement example is arranged between the object 2 and the light detection unit 46.

  FIG. 35 shows details of the lens 40 in the fifteenth arrangement example. In the fifteenth arrangement example, the lens 40 is configured by five lenses in which the lenses LS1, LS2, and LS3 are added to the lens 40 used in the second arrangement example including the lens 403 and the lens 404. Of the five lenses constituting the lens 40, 403 and 404 are spherical lenses, and LS1, LS2, and LS3 are cylindrical lenses. In the image forming action by the lens, different actions are shown in the x and y directions by these cylindrical lenses. The beam splitter 12 is arranged on the rear focal plane of the lens 403 constituting the lens 40 so as to divide substantially zero-order light into two. The light reflected by the beam splitter 12 is input to the lens 60 as the second light.

  That is, the lens LS1 and the lens LS3 do not contribute to image formation because they do not have a curvature shape in the x direction. Therefore, the x direction is equivalent to a configuration in which only the lenses 403, 404, and LS2 are arranged as shown in the upper part of FIG. On the other hand, the lens LS2 does not contribute to image formation because it does not have a curvature shape in the y direction. Therefore, in the y direction, this is equivalent to a configuration in which only lenses 403, 404, LS1, and LS3 are arranged as shown in the lower part of FIG.

  In the x direction, the image of the object 2 is once formed on the surface IP by the lenses 403 and 404. Next, the front focal plane of the lens LS2 is different from the plane IP of the image of the object 2, and the rear focal plane of LS2 is different from the light receiving plane of the photodetector 46. Therefore, a Fresnel diffraction image of the image formed on the surface IP is formed on the light receiving surface. On the other hand, in the y direction, an image of the object 2 is once formed on the surface IP by the lenses 403 and 404. The lenses LS1 and LS3 do not have a so-called 4f optical system configuration. That is, as shown in the lower part of FIG. 35, the front focal plane of LS3 does not coincide with the rear focal plane of LS1. Therefore, the image of the object 2 and the francophor diffraction image are not formed on the light receiving surface. Therefore, the lens 40 formed a Fresnel diffraction image of the object 2 in the x direction and a Fresnel diffraction image of the object 2 in the y direction on the light receiving surface of the photodetector 46.

Next, a method for processing a signal obtained by the photodetector 46 using such a lens 40 will be described. The coordinate system on the light receiving surface of the photodetector 46 is the u "v" plane as in the third or sixth arrangement example. In the third or sixth arrangement example, the Fresnel diffraction image appears on the u "v" plane in the u "and v" directions. Also in the fifteenth arrangement example, Fresnel diffraction images appear in the u "direction and the v" direction. That is, the fifteenth arrangement example is different from the third or sixth arrangement example in the configuration of the lens 40. A signal representing the sum of signals on a straight line parallel to the v ″ direction is defined as s ₁₅ (u ″, t). Arithmetic processing for obtaining a complex amplitude image g (ξ, η) based on s ₁₅ (u ″, t) output from the light detection unit 46 and arithmetic unit configurations for performing this processing are the third and sixth arrangement examples. Same as the arithmetic processing for obtaining the complex amplitude image g (ξ, η) of the object 2 based on the obtained s ₃ (u ″, t) and s ₆ (u ″, t) and the arithmetic unit configuration for performing this processing. Therefore, the description of the arithmetic processing for obtaining the complex amplitude image g (ξ, η) based on s ₁₅ (u ″, t) output from the light detection unit 46 and the arithmetic unit configuration that performs this processing is omitted. To do.

The calculation units 50 of the first to fifteenth arrangement examples described above have the first Fourier transform unit 51, which is a calculator that performs a one-dimensional Fourier transform on the time variable t, and the frequency Ω, as shown in FIG. A specific region cutout unit 55 that is a calculator that _cuts out data in a region that includes the Nyquist frequency f _nyq as the center, a third Fourier transform unit 53 that is a calculator that performs one-dimensional Fourier related to time frequency, and a one-dimensional value related to the first direction. It is comprised from the 4th Fourier-transform part 54 which is a computing unit which performs a Fourier-transform. Hereinafter, in the present specification, the four types of arithmetic units are collectively referred to as basic arithmetic units.

In the first to fifteenth arrangement examples, the light detection unit 46 and the calculation unit 50 are arranged in parallel in the direction perpendicular to the paper surface of FIG. 36 (X direction). In Figure 36, of the light detection unit 46 and the arithmetic unit 50 are arranged in parallel, is a diagram illustrating an optical detection unit 46 and the arithmetic unit 50 at the position u _n. 37 to 41, 44, 45, and 46 shown below, the light detection unit 46 and the calculation unit 50 are arranged in parallel in the direction perpendicular to the paper surface (X direction). is one of the light detection unit 46 and the arithmetic unit 50 is disposed, it is a diagram illustrating a light detection unit 46 and the arithmetic unit 50 at the position u _n. It should be noted that the position u _n is described as u ′ _n , u ″ _n according to the arrangement example.

(16th arrangement example)
Next, a sixteenth arrangement example will be described. The sixteenth arrangement example is different from the first to fifteenth arrangement examples in that each arrangement includes an output totalizer (output totalizer) 58 that calculates the sum of outputs from the plurality of light detection units 46 and the plurality of photodetectors 46. Accordingly, in the sixteenth arrangement example, the arrangement of the basic arithmetic units is different from those in the first to fifteenth arrangement examples.

  In the sixteenth arrangement example, one light source unit 10, one lens 40, M (M> 1) detection units (a plurality of detectors), a plurality of basic arithmetic units, and output totalizers 58 are provided. And an arithmetic unit 50 including the same.

  In the sixteenth arrangement example, the M light detection units 46 are arranged in the second direction. The m-th photo detectors 46m arranged in the second direction output data representing the sum in the second direction at each time for each position in the first direction.

  The calculation unit 50 in the sixteenth arrangement example includes output summing devices 58 that are calculation units that input the outputs of M detection units arranged in the second direction and output the sum of 1 to M. Each output summation device 58 may receive the outputs of M basic arithmetic units that receive the outputs of M light detection units 46 arranged in the second direction, and may output the summation from 1 to M. .

  As shown in FIG. 37, when each output summation device 58 is in a stage preceding the first Fourier transform unit 51, each output summation device 58 inputs M signals output from the M detection units. Each output summer 58 obtains the sum from 1 to M for each of the M signals and outputs the result for each time.

  As shown in FIGS. 38 and 39, when each output summation device 58 is between the first Fourier transform unit 51 and the third Fourier transform unit 53, each output summation device 58 is subjected to Fourier transform by the first Fourier transform unit 51. The converted M signals are input. As shown in FIG. 38, when each output summation device 58 is arranged immediately after the first Fourier transform unit 51, each output summation device 58 outputs M signals output from the first Fourier transform unit 51. input. In addition, as shown in FIG. 39, when each output summation device 58 is arranged immediately after the specific region cutout portion 55, each output summation device 58 outputs M signals output from the specific region cutout portion 55. Enter. Each output summer 58 obtains a sum of 1 to M for each time frequency for M signals and outputs a result for each time frequency.

  As shown in FIG. 40 and FIG. 41, when each output summation device 58 is in a stage subsequent to the third Fourier transform unit 53, each output summation device 58 has the third Fourier transform unit 53 or the fourth Fourier transform unit 54. Input M signals to be output. Each output summation unit 58 obtains a sum from 1 to M for each of the M signals and outputs a result for each time.

Next, the output of each output summer 58 will be described. When each output summation device 58 is located between the first Fourier transform unit 51 and the third Fourier transform unit 53, each output summation device 58 is 1 to M for each time frequency ω (= Ω + ω _d ) according to the equation (24). Get the sum up to. Here, S ^(m) (u, ω) is input to the output data s ^(m) (u, t) of the detection unit arranged m-th in the second direction of the first Fourier transform unit 51, and the time variable An output signal of the first Fourier transform unit 51 that performs Fourier transform on t is represented. Due to the linearity of the Fourier transform, the Fourier operator FT _{t in the} middle side of the equation (24) can be exchanged with the summation operator Σ, and as a result, the rightmost side of the equation (24) is obtained.

The term on which the one-dimensional Fourier transform operator FT _t acts on the time variable t on the rightmost side is the sum s (u, u, t) of the waveforms s ^(m) (u, t) output from the M detectors. t). That is, each output summer 58 provided in the calculation unit outputs the output of the first Fourier transform unit 51 that receives the signal output from the detection unit in the first to fifteenth arrangement examples. Accordingly, it can be said that the sixteenth arrangement example includes a part of the detection unit that outputs data representing the sum in the second direction at each time in the calculation unit.

On the other hand, when each output summation device 58 is in a stage subsequent to the third Fourier transform unit 53, each output summation device 58 obtains a summation from 1 to M for each time according to the equation (25). Here, s ′ ^(m) (u, t) represents the output data of the third Fourier transform unit 53m. At the input of the third Fourier transform unit 53m, the output of the m-th detection unit arranged in the second direction is sent to the third Fourier transform unit 53m via the first Fourier transform unit 51m and the specific region cutout unit 55m. Connected with. The one-dimensional Fourier transform of the time variable t of s ′ ^(m) (u, t) is S ′ ^(m) (u, ω _d ). The term on which the one-dimensional Fourier transform operator FT _{ω on} the right side of the equation (25) acts is output data of the specific region cutout unit 55. Therefore, the input of the specific area cutout 55 is a signal S ^(m) (u, Ω + ω _d ) shifted by the frequency Ω shown on the left side of the equation (26). Further, the rightmost side of the equation (26) represents the sum of the waveforms s ^(m) (u, t) output from the M detection units for each time from 1 to M.

  That is, since the output of each output summation device 58 provided in the arithmetic unit coincides with the signal output by the detection unit in the first to fifteenth arrangement examples, the sixteenth arrangement example has data representing the sum in the second direction. It can be said that the calculation unit includes a part of the detection unit that outputs at each time.

An embodiment in the case of the sixteenth arrangement example will be described below. In the sixteenth arrangement example, the same lens 40 as in the first arrangement example shown in FIG. 11 is used. That is, the light receiving surface of the photodetector 46 is the rear focal plane in the first direction of the lens 40 and is disposed on the rear focal plane in the second direction of the lens 40. The photodetector 46 has a two-dimensional pixel, and a digital CCD camera having a pixel size of 8.3 × 8.3 μm and a pixel number of 640 × 480 is used. The frame rate f _CCD was 30 Hz. Let the v-direction pixel number be m and the u-direction pixel number be n. The photodetector 46 is arranged so that the moving object moves in a direction parallel to the v direction. Of the total pixels 640 × 480 pixels of the photodetector 46, only the region of 312 × 312 pixels was used for the experiment. Therefore, M = N = 312. M and N represent the number of vertical and horizontal pixels, and the lowercase letters m and n represent pixel numbers.

That is, the photodetector 46 in the sixteenth arrangement example is a photodetector in which M one-dimensional line sensors in which N light receiving cells d _n ^(m) are arranged in the first direction are arranged in the second direction. After Fourier transformation with respect to time variable t for the time waveform ^s outputted from the light receiving cell ^{_{d n (m) (m)}} (u, t), the resulting waveform was ^{S (m) (u, ω} ) . FIG. 42 shows a time waveform s ^(m) (u, t), and FIG. 43 shows S ^(m) (u, ω).

(17th arrangement example)
As in the sixteenth arrangement example, the seventeenth arrangement example includes a plurality of light detection units 46 and output totalizers 58. That is, in the seventeenth arrangement example, similarly to the sixteenth arrangement example, one light source unit 10, one lens 40, M (M> 1) light detection units 46, and a calculation unit 50 are configured. The The computing unit 50 includes a plurality of basic computing units and output summing units 58 for obtaining the sum of outputs from the light detecting unit 46. That is, in the seventeenth arrangement example, a plurality of detectors are provided, and the calculation unit 50 further includes an output summation device 58 that calculates a sum of outputs from the plurality of detectors.

  If the lens 40 and the calculation unit 50 are regarded as the calculation unit, the lens 40 is incorporated in the calculation unit 50 in the seventeenth arrangement example. In the seventeenth arrangement example, M (M> 1) detection units are arranged on the lens 40 used in the first arrangement example, and further, an arithmetic unit (hereinafter referred to as a second calculator) that performs Fourier transformation or Fresnel transformation in the second direction. A direction changer 59 (referred to as a second direction change unit) is added.

As illustrated in FIGS. 44, 45, and 46, the second direction changer 59 is disposed in front of each output summation device 58 in the calculation unit 50 that inputs the output from the light detection unit 46. The second direction converter 59 inputs M outputs at the position n (u _n , u ′ _n , u ″ _n ) regardless of the calculation position, and outputs the calculation result.

  When the second direction converter 59 is a Fourier transformer, it is equivalent to the eighth arrangement example in which the Fraunhofer diffraction image is received in the first direction and the object image is received in the second direction on the light receiving surface of the photodetector 46. It is. That is, the lens 40 used in the first arrangement example and the second direction changer 59 constitute the lens 40 in the eighth arrangement example.

  When the second direction converter 59 is a Fresnel converter, the ninth arrangement example receives the Fraunhofer diffraction image in the first direction and the Fresnel diffraction image in the second direction on the light receiving surface of the photodetector 46. Is equivalent. That is, the lens 40 used in the first arrangement example and the second direction changer 59 constitute the lens 40 in the ninth arrangement example.

(18th arrangement example)
As in the sixteenth arrangement example, the eighteenth arrangement example includes a plurality of light detection units 46 and output totalizers 58. That is, in the eighteenth arrangement example, similarly to the sixteenth arrangement example, in the sixteenth arrangement example, one light source unit 10, one lens 40, M (M> 1) detection units, and a plurality of basic units. It comprises an arithmetic unit 50 including an arithmetic unit and each output summation device 58. That is, in the eighteenth arrangement example, a plurality of detectors are provided, and the calculation unit 50 further includes an output totalizer 58 that calculates a sum of outputs from the plurality of detectors.

  If the lens 40 and the calculation unit 50 are regarded as the calculation unit, the lens 40 is incorporated in the calculation unit 50 in the eighteenth arrangement example. In the eighteenth arrangement example, M (M> 1) detection units are arranged on the lens 40 used in the second arrangement example, and further, a second transform that performs Fourier transform or Fresnel transform in the second direction (that is, with respect to m) is performed. This is a configuration in which a direction changer 59 is added.

As shown in FIGS. 44, 45, and 46, the second direction changer 59 is arranged in the preceding stage of each output summation device 58 in the calculation unit that inputs the output from the detection unit. The second direction converter 59 inputs M outputs at the position n (u _n , u ′ _n , u ″ _n ) regardless of the calculation position, and outputs the calculation result.

  When the second direction transformer 59 is a Fourier transformer, it is equivalent to the tenth arrangement example in which the object image is received in the first direction and the Franforfer diffraction image is received in the second direction on the light receiving surface of the photodetector 46. is there. That is, the lens 40 used in the second arrangement example and the second direction changer 59 constitute the lens 40 in the tenth arrangement example.

  When the second direction converter 59 is a Fresnel converter, this is equivalent to the twelfth arrangement example in which the object image is received in the first direction and the Fresnel diffraction image is received in the second direction on the light receiving surface of the photodetector 46. That is, the lens 40 used in the second arrangement example and the second direction changer 59 constitute the lens 40 in the twelfth arrangement example.

In the case where the second direction converter 59 is a Fourier transformer, calculation processing in the eighteenth arrangement example will be described. The waveform Re [FT _m [s ^(m) (u ′, t)]] output from the second direction converter 59 is sent to each output summation device 58, summed with respect to m, and s (u ′, t ) FT _m represents a one-dimensional Fourier transform with respect to the variable m. Re is an operator that takes the real part of a complex number. That is, since the lens 40 of the tenth arrangement example is configured by the lens 40 used in the second arrangement example and the second direction changer 59, the data output from each output summer 58 is the tenth arrangement example. This is the same as the signal output by the detector. Furthermore, since the signal output from the detection unit of the tenth arrangement example is the same as the calculation method of the second arrangement example, the calculation of the eighteenth arrangement example is the same as the calculation method of the second arrangement example. Thus, a complex amplitude image g (ξ, η) of the object 2 is obtained.

(19th arrangement example)
As in the sixteenth arrangement example, the nineteenth arrangement example includes a plurality of light detection units 46 and output totalizers 58. That is, in the nineteenth arrangement example, similarly to the sixteenth arrangement example, one light source unit 10, one lens 40, M detection units (M> 1), a plurality of basic arithmetic units, and each output The calculation unit 50 includes a summer 58. That is, in the nineteenth arrangement example, a plurality of detectors are provided, and the calculation unit 50 further includes an output totalizer 58 that calculates a sum of outputs from the plurality of detectors.

  If the lens 40 and the calculation unit 50 are regarded as the calculation unit, the lens 40 is incorporated in the calculation unit 50 in the nineteenth arrangement example. In the nineteenth arrangement example, M (M> 1) detection units are arranged on the lens 40 used in the third arrangement example, and further, a second transform that performs Fourier transform or Fresnel transform in the second direction (that is, with respect to m) is performed. This is a configuration in which a direction changer 59 is added.

As shown in FIGS. 44, 45, and 46, the calculation position of the second direction converter 59 is arranged in the preceding stage of each output summation device 58 in the calculation unit that inputs the output from the detection unit. The second direction converter 59 inputs M outputs at the position n (u _n , u ′ _n , u ″ _n ) regardless of the calculation position, and outputs the calculation result.

  When the second direction converter 59 is a Fourier transformer, it is equivalent to the fifteenth arrangement example in which the Fresnel diffraction image is received in the first direction and the Fresnel diffraction image is received in the second direction on the light receiving surface of the photodetector 46. . That is, the lens 40 used in the third arrangement example and the second direction changer 59 constitute the lens 40 in the fifteenth arrangement example.

  When the second direction converter 59 is a Fresnel converter, it is equivalent to the fifteenth arrangement example in which the Fresnel diffraction image is received in the first direction and the Fresnel diffraction image is received in the second direction on the light receiving surface of the photodetector 46. . That is, the lens 40 used in the third arrangement example and the second direction changer 59 constitute the lens 40 in the fifteenth arrangement example.

  Next, the calculation position in the calculation unit 50 that receives the output from the light detection unit 46 of the second direction changer 59 will be described. When the second direction changer 59 is included in the lens 40, it is the position of the lens 40. When the second direction converter 59 is not included in the lens 40, the second direction converter 59 is arranged in front of each output summation device 58 in the calculation unit 50 that inputs the output from the light detection unit 46. The

  When the second direction converter 59 is between the detection unit and the first Fourier transform unit 51, the input of the second direction converter 59 is the output from the M detection units at every time, and every time The calculation result is output.

  When the second direction converter 59 is between the first Fourier transform unit 51 and the third Fourier transform unit 53, the input of the second direction converter 59 is input from outputs from M detection units for each time frequency. The calculation result is output for each time frequency.

When the second direction converter 59 is in a stage subsequent to the third Fourier transform unit 53, the input of the second direction converter 59 is the output from M detection units at each time, and the calculation result at each time. Is output.

(20th arrangement example)
Next, a twentieth arrangement example will be described. In the first to nineteenth arrangement examples, the method of separating the 0th order light and the higher order light (non-Doppler shift light and Doppler shift light) out of the object light (fluorescence scattered light from the object) is described in Reference 1 (Gabriel Popescu, “Fourier phase”). microscopy for investigation of biological structures and dynamics, ”Optics letters, 29, 2503, (2004).). That is, the lens 40 is disposed between the object 2 and the light receiving surface of the photodetector 46. In addition, the lens 40 temporarily forms a Franforfer diffraction image between the object 2 and the light receiving surface of the photodetector 46. Substantially zero-order light gathering near the center of the Franforfer diffraction image was used as reference light.

  In the twentieth arrangement example, the diffraction grating described in Reference 2 (Gabriel Popescu, “Diffraction phase microscopy for quantifying cell structure and dynamics,” Optics letters, 31, 775, (2006).) Is used as a method of extracting substantially zero-order light. . FIG. 47 shows a specific optical system.

  As shown in FIG. 47, the lens 40 is disposed between the object 2 and the light receiving surface of the photodetector 46. The lens 40 temporarily forms a Franforfer diffraction image following the object image between the object 2 and the light receiving surface of the photodetector 46. The lens 40 in the twentieth arrangement example includes the lens 40 in the second arrangement example and lenses 407 and 408 that relay an object image formed by the lens 40. The lens 407 and the lens 408 constitute a 4f optical system. The lens 40 in the twentieth arrangement example is composed of four spherical lenses.

  By configuring the lens 40 as described above, an object image of the object 2 is formed between the lens 404 and the lens 407, and a francophor diffraction image of the object 2 is formed between the lens 407 and the lens 408. The The surface on which an object image can be formed is called an object image surface, and the surface on which a Franforfer diffraction image can be formed is called a Franforfer diffraction image surface.

  A diffraction grating is disposed on the object image plane, and a beam splitter 12 is disposed on the Franforfer diffraction image plane. The diffraction grating forms a plurality of Franforfer diffraction images on the Franforfer diffraction image plane. Of these, the 0th order and + 1st order diffraction images are referred to as a 0th order diffraction image and a 1st order diffraction image, respectively. The direction of the unevenness in the diffraction grating coincides with the X direction. For this reason, the zero-order diffraction image and the first-order diffraction image are arranged in a straight line perpendicular to the Y direction by the diffraction grating.

  The pinhole 63 is two holes formed so as to include substantially the 0th order light and the 1st order diffraction image of the 0th order diffraction image created by the diffraction grating. Of the 0th-order diffraction image, the light that has passed through a hole (pinhole 63A) that is formed to include substantially 0th-order light becomes second light, which is input to the first modulation via the beam splitter 12 and the lens 60. The The light that has passed through the hole (pinhole 63B) drilled to include the first-order diffraction image becomes the first light and is input to the lens 408. That is, since the light is split into the first light and the second light by the diffraction grating, the pinhole 63A, and the pinhole 63B, these optical elements play the same role as the beam splitter 12 in the first to nineteenth arrangement examples. .

  The beam splitter 12 of the twentieth arrangement example may be a mirror that reflects light and does not transmit light. The beam splitter 12 outputs, to the lens 60, light that has passed through a hole (pin hole 63A) that is formed so as to include substantially zero-order light in the pin hole 63. The front focal plane of the lens 60 is on the same plane as the pinhole 63, and the front focal plane of the lens 60 coincides with the center of the pinhole 63A. By configuring as described above, in the twentieth arrangement example as well, as in the first to nineteenth arrangement examples, substantially zeroth-order light can be extracted as reference light.

(21st arrangement example)
In the first to twentieth arrangement examples, the observation device 1 includes a first modulator and a second modulator to which modulation frequencies different in frequency by Ω are provided, and the Nyquist frequency f _nyq is set back and forth around the frequency Ω. The area to be included is cut out. As shown in FIG. 48, the present arrangement example uses the first to twentieth arrangements in that a single frequency modulator 70 (one modulator) is used instead of the first modulator and the second modulator. Different from the example. For example, the frequency modulator 70 is a modulator using an acousto-optic effect.

When the frequency Ω output from the first signal generator 21 and amplified by the first amplifier 22 is supplied to the frequency modulator 70, the light of the optical frequency ω reflected by the beam splitter 12 and input to the frequency modulator 70. Is subjected to frequency modulation and output from the output terminal of the frequency modulator 70 as light having an optical frequency ω + nΩ (n: integer). For this reason, in the photodetector 46, a beat signal having a difference frequency between the scattered light and the reference light is observed by heterodyne interference. Here, the frequency Ω applied to the frequency modulator 70 is determined so that the maximum Doppler shift frequency ω _dmax of fluorescence due to the movement of the object 2 satisfies the condition of Ω> ω _dmax .

Note that the maximum Doppler shift frequency ω _dmax has the same value as the Nyquist angular frequency ω _nyq . Here, the Nyquist angular frequency ω _nyq is an angular frequency notation of the Nyquist frequency f _nyq shown in the above equation (6), and ω _nyq = 2π · f _nyq .

In this arrangement example, the arithmetic unit 50 _cuts out a region including the Nyquist frequency f _nyq in the front and rear with the frequency Ω applied to the frequency modulator 70 as the center. In addition, as described above, the light output from the frequency modulator 70 includes light having a frequency of ω + nΩ. Therefore, if the light is appropriately selected as the reference light, an interference signal obtained by the photodetector 46 is obtained. , A signal including nΩ is observed. For this reason, the Nyquist frequency f _nyq is centered around nΩ (n: an integer other than 0) that is a double wave of the frequency Ω applied to the frequency modulator 70, such as a secondary wave (2Ω) and a tertiary wave (3Ω). You may cut out the area | region included before and behind.

The configuration composed of one modulator described above can be applied to the first to twentieth arrangement examples. That is, by providing the frequency modulator 70 instead of the first modulator and the second modulator provided in the first to twentieth arrangement examples, the same output as the output shown in the first to twentieth arrangement examples is obtained. be able to. In this case, the computing unit 50 is the first to twentieth arrangement example except that the region including the Nyquist frequency f _nyq before and after the frequency Ω to be applied to the frequency modulator 70 or nΩ that is a harmonic of the frequency Ω is cut out. The same arithmetic processing and arithmetic unit configuration as shown in FIG. That is, the data of the region including the Nyquist frequency around the modulation frequency Ω in one modulator or nΩ that is the harmonic of the data obtained by the one-dimensional Fourier transform with respect to the time variable t. Is subjected to Fourier transform to obtain a complex amplitude image g (ξ, η).

  In this arrangement example, a single frequency modulator 70 is used instead of the first modulator and the second modulator. Therefore, the number of modulators to be used can be reduced, and the observation apparatus 1 can be downsized. Moreover, the manufacturing cost of the observation apparatus 1 can be reduced.

  In the observation apparatus 1 of the present embodiment, when the speed of the object 2 changes, frequency modulation occurs in the Doppler signal, and the finally obtained image of the object 2 expands and contracts in the flow direction. In order to correct such expansion and contraction, it is preferable that the observation apparatus 1 of the present embodiment further includes a speed detection unit that detects the moving speed of the object 2. And the calculating part 50 correct | amends regarding the speed change of the target object 2 in the time of the one-dimensional Fourier transformation of a time direction, or two-dimensional Fourier transformation based on the speed of the target object 2 detected by the speed detection part. Is preferred. Alternatively, the imaging timing of the photodetector 46 may be achieved based on the speed of the object 2 detected by the speed detection unit.

This speed detection unit may be any one, but uses the relationship between the moving speed and the Doppler shift amount to detect the frequency of the signal at the scattered light arrival position of the rear focal plane of the lens 40. However, the moving speed of the object 2 can be obtained. In this case, the speed detection unit may detect a part of the light branched from the beam splitter 41 toward the photodetector 46 on the Fourier plane, or may detect one of the light receiving surfaces of the photodetector 46. It may include a pixel provided independently in the part. The size of the pixel, it is preferable to have an area with a resolution of the moving speed derived from the relationship between the moving speed V and the Doppler frequency f _d of the object 2.

  In the observation apparatus 1 of the present embodiment, in the first arrangement example, among the fluorescence from the object 2, the fluorescence (substantially zero-order light) emitted in the optical axis direction is collected at one point by the lens 40. When the substantially zero-order light reaches the light receiving surface of the photodetector 46, the quality of the signal obtained by the photodetector 46 deteriorates. Therefore, it is preferable to provide a neutral density filter 47 for attenuating the substantially zero-order light so that the substantially zero-order light does not reach all the light receiving surface of the photodetector 46. Alternatively, it is preferable to irradiate the object 2 with the light L0 having a beam cross-section so that the generation of substantially zero-order light is small. Then, it is preferable to correct the intensity unevenness in consideration of the transmittance of the neutral density filter 47.

  In the above description, the case where the object 2 moves in one direction on the ξη plane has been described. The present invention is also applicable when the object 2 reciprocates in the ζ direction (the direction of the optical axis of the lens 40) perpendicular to the ξη plane. In this case, since a Doppler shift occurs in the radial direction on the rear focal plane of the lens, a photodetector having a pixel structure in the circumferential direction and each pixel extending radially is used.

  In the above description, the embodiment in which the fluorescent image of the object of the light source is mainly obtained by the transmitted illumination is shown. However, it is obvious that the fluorescence image may be obtained by the reflected (epi-illumination) illumination or the ultra-illumination. As the light source, it is preferable to use light of a single longitudinal mode, but the present invention is not limited to this. For example, the fluorescence intensity can be increased by using broadband light. In addition, it is preferable to use light having a constant phase relationship between wavelength components as broadband light. For example, a mode-locked laser can be used as such a light source.

  Circulating Tumor Cell (CTC), which has been attracting attention in recent years, is contained in normal blood nucleated cells (white blood cells) at a frequency of about 1 / 10,000,000. Rapid inspection is required. The present invention can be used in such fields. The present invention can also be applied to flow cytometry with high throughput. In the present invention, since the moving object 2 can be observed using a one-dimensional photodetector 46, the frame rate can be improved, and the object 2 such as a cell can be moved at high speed. The inspection efficiency can be improved because the flow can be performed. In addition, it is possible to photograph a cell sample or tissue sample obtained by being attached to a slide glass with high contrast without staining. Further, a complex amplitude image by reflected light as in a metal microscope can be obtained.

  DESCRIPTION OF SYMBOLS 1 ... Observation apparatus, 2 ... Object, 10 ... Light source part, 11 ... Illuminating lens, 12 ... Beam splitter, 20 ... 1st modulator, 21 ... 1st signal generator, 22 ... 1st amplifier, 30 ... 2nd Modulator, 31 ... second signal generator, 32 ... second amplifier, 40 ... lens, 41 ... beam splitter, 42,43 ... mirror, 44 ... lens, 45 ... filter, 46 ... photodetector, 47 ... neutral density filter , 50 ... arithmetic unit, 51 ... first Fourier transform unit, 52 ... second Fourier transform unit, 53 ... third Fourier transform unit, 54 ... fourth Fourier transform unit, 55 ... specific region cutout unit, 56 ... initial phase Correction unit, 57... Secondary phase division unit, 58... Output totalizer, 59... Second direction converter, 60.

Claims (31)

A light source unit that excites a fluorescent material included in an object moving in a direction parallel to a predetermined plane and irradiates the object with light that generates fluorescence from the object;
A direction on the predetermined plane of the Doppler shift effect due to movement of the object in the light that has reached the said predetermined plane of the fluorescence generated from the object by the light irradiation from the light source unit is constant, the When the direction perpendicular to the moving direction of the object is the first direction and the direction on the predetermined plane orthogonal to the first direction and the direction parallel to the moving direction of the object is the second direction , Data representing the sum in the second direction of data that temporally changes at a frequency corresponding to the Doppler shift amount of the light reaching each position on the predetermined plane, for each position in the first direction A detector that outputs the time, and
The two-dimensional Fourier transform is performed by performing a one-dimensional Fourier transform on the time variable for the data having the position and time in the first direction on the predetermined plane as variables, and the two-dimensional Fourier transform for the data after the Fourier transform. A calculation unit for obtaining data obtained by the conversion as an image of the object;
With
The detection unit is
Fluorescence generated from the object by light output from the light source unit is input, and the input fluorescence is divided into two at the subsequent stage of the object to be first light and second light, and the first light An optical system that causes heterodyne interference between the first light and the modulated second light on the predetermined plane after modulating the light of 2 with a modulator;
A photodetector having a light receiving surface in the predetermined plane and having a pixel structure in the first direction on the light receiving surface;
Including an observation device. The calculation unit
A first Fourier transform unit for performing a one-dimensional Fourier transform on the time variable;
A second Fourier transform unit for performing the two-dimensional Fourier transform;
With
The second Fourier transform unit includes a third Fourier transform unit that performs a one-dimensional Fourier transform on a frequency, and a fourth Fourier transform unit that performs a one-dimensional Fourier transform on the first direction.
The observation apparatus according to claim 1. A lens disposed between the light source unit and the detection unit;
The light receiving surface of the detection unit is a rear focal plane in the first direction of the lens, and is disposed on the rear focal plane in the second direction of the lens,
The arithmetic unit sequentially performs one-dimensional Fourier transformation on the time variable, one-dimensional Fourier transformation on the frequency, and one-dimensional Fourier transformation on the first direction for the data output from the detection unit .
The observation apparatus according to claim 2. A lens disposed between the light source unit and the detection unit;
The light receiving surface of the detection unit is a surface on which the lens forms a franphophor diffraction image of the object in the first direction, and forms a franphophor diffraction image of the object in the second direction. Placed on the surface
The arithmetic unit sequentially performs one-dimensional Fourier transformation on the time variable, one-dimensional Fourier transformation on the frequency, and one-dimensional Fourier transformation on the first direction for the data output from the detection unit .
The observation apparatus according to claim 2. A lens disposed between the light source unit and the detection unit;
The light-receiving surface of the detection unit is a surface on which a Francophor diffraction image of the object is formed in the first direction by the lens, and an image in which an image of the object is formed in the second direction Placed on the surface,
The arithmetic unit sequentially performs one-dimensional Fourier transformation on the time variable, one-dimensional Fourier transformation on the frequency, and one-dimensional Fourier transformation on the first direction for the data output from the detection unit .
The observation apparatus according to claim 2. A lens disposed between the light source unit and the detection unit;
The light-receiving surface of the detection unit is a surface on which the lens makes a Francophor diffraction image of the object in the first direction, and forms a Fresnel diffraction image of the object in the second direction. Placed on the surface,
The arithmetic unit sequentially performs one-dimensional Fourier transformation on the time variable, one-dimensional Fourier transformation on the frequency, and one-dimensional Fourier transformation on the first direction for the data output from the detection unit .
The observation apparatus according to claim 2. A lens disposed between the light source unit and the detection unit;
The light receiving surface of the detection unit is an imaging surface on which an image of the object is formed in the first direction by the lens, and a francophor diffraction image of the object is formed in the second direction. Placed on the surface,
Before Symbol lenses have row one-dimensional Fourier transform for the first direction,
The arithmetic unit, for the data output from the detection unit, a one-dimensional Fourier transform related to the time variable, a one-dimensional Fourier transform related to the first direction, a one-dimensional Fourier transform related to the frequency, and a one-dimensional Fourier related to the first direction. Perform conversion in order ,
The observation apparatus according to claim 2. A lens disposed between the light source unit and the detection unit;
The light receiving surface of the detection unit is an image forming surface on which the image of the object is formed in the first direction by the lens, and an image forming surface on which the image of the object is formed in the second direction. Arranged,
Before Symbol lenses have row one-dimensional Fourier transform for the first direction,
The arithmetic unit, for the data output from the detection unit, a one-dimensional Fourier transform related to the time variable, a one-dimensional Fourier transform related to the first direction, a one-dimensional Fourier transform related to the frequency, and a one-dimensional Fourier related to the first direction. Perform conversion in order,
The observation apparatus according to claim 2. A lens disposed between the light source unit and the detection unit;
The light receiving surface of the detection unit is an imaging surface on which an image of the object is formed in the first direction by the lens, and a surface on which a Fresnel diffraction image of the object is formed in the second direction. Arranged,
Before Symbol lenses have row one-dimensional Fourier transform for the first direction,
The arithmetic unit, for the data output from the detection unit, a one-dimensional Fourier transform related to the time variable, a one-dimensional Fourier transform related to the first direction, a one-dimensional Fourier transform related to the frequency, and a one-dimensional Fourier related to the first direction. Perform conversion in order,
The observation apparatus according to claim 2. A lens disposed between the light source unit and the detection unit;
The light receiving surface of the detection unit is a surface on which a Fresnel diffraction image of the object is formed in the first direction by the lens, and a Francophor diffraction image of the object is formed in the second direction. Placed on the surface,
The arithmetic unit, for the data output from the detection unit, a one-dimensional Fourier transform related to the time variable, a one-dimensional Fourier transform related to the frequency, a one-dimensional Fourier transform related to the first direction, and a one-dimensional Fourier related to the first direction. Perform conversion in order,
The observation apparatus according to claim 2. A lens disposed between the light source unit and the detection unit;
The light receiving surface of the detection unit is a surface on which a Fresnel diffraction image of the object is formed in the first direction by the lens, and an imaging surface on which the image of the object is formed in the second direction. Arranged,
The arithmetic unit, for the data output from the detection unit, a one-dimensional Fourier transform related to the time variable, a one-dimensional Fourier transform related to the frequency, a one-dimensional Fourier transform related to the first direction, and a one-dimensional Fourier related to the first direction. Perform conversion in order,
The observation apparatus according to claim 2. A lens disposed between the light source unit and the detection unit;
The light receiving surface of the detection unit is a surface on which a Fresnel diffraction image of the object is formed in the first direction by the lens, and a surface on which the Fresnel diffraction image of the object is formed in the second direction. Arranged,
The arithmetic unit, for the data output from the detection unit, a one-dimensional Fourier transform related to the time variable, a one-dimensional Fourier transform related to the frequency, a one-dimensional Fourier transform related to the first direction, and a one-dimensional Fourier related to the first direction. Perform conversion in order,
The observation apparatus according to claim 2. A lens disposed between the light source unit and the detection unit;
The light receiving surface of the detection unit is a surface on which a Fresnel diffraction image of the object is formed in the first direction by the lens, and a surface on which the Fresnel diffraction image of the object is formed in the second direction. Arranged,
The arithmetic unit, for the data output from the detection unit, a one-dimensional Fourier transform related to the time variable, a one-dimensional Fourier transform related to the first direction, a one-dimensional Fourier transform related to the frequency, and a one-dimensional Fourier related to the first direction. Perform conversion in order,
The observation apparatus according to claim 2. A light source unit that excites a fluorescent material included in an object moving in a direction parallel to a predetermined plane and irradiates the object with light that generates fluorescence from the object;
A direction on the predetermined plane of the Doppler shift effect due to movement of the object in the light that has reached the said predetermined plane of the fluorescence generated from the object by the light irradiation from the light source unit is constant, the When the direction perpendicular to the moving direction of the object is the first direction and the direction on the predetermined plane orthogonal to the first direction and the direction parallel to the moving direction of the object is the second direction , Data representing the sum in the second direction of data that temporally changes at a frequency corresponding to the Doppler shift amount of the light reaching each position on the predetermined plane, for each position in the first direction A detector that outputs the time, and
With respect to data having the position and time in the first direction on the predetermined plane as variables, a one-dimensional Fourier transform with respect to a time variable, a one-dimensional Fourier transform with respect to a frequency, and a one-dimensional Fourier transform with respect to the first direction are performed. A calculation unit that obtains the data obtained by the one-dimensional Fourier transform as an image of the object;
With
The detection unit is
Fluorescence generated from the object is input by the light output from the light source unit, and the input fluorescence is divided into two at the subsequent stage of the object to be the first light and the second light, and the second An optical system for heterodyne interference between the first light and the modulated second light on the predetermined plane,
A photodetector having a light receiving surface in the predetermined plane and having a pixel structure in the first direction on the light receiving surface;
Including an observation device. A lens disposed between the light source unit and the detection unit;
The light receiving surface of the detection unit is an image forming surface on which the image of the object is formed in the first direction by the lens, and an image forming surface on which the image of the object is formed in the second direction. Arranged,
Before Symbol lenses have row one-dimensional Fourier transform for the first direction,
The arithmetic unit sequentially performs a one-dimensional Fourier transform on the time variable and a one-dimensional Fourier transform on the frequency for the data output from the detection unit.
The observation apparatus according to claim 14. A lens disposed between the light source unit and the detection unit;
The light receiving surface of the detection unit is an imaging surface on which an image of the object is formed in the first direction by the lens, and a francophor diffraction image of the object is formed in the second direction. Placed on the surface,
Before Symbol lenses have row one-dimensional Fourier transform for the first direction,
The arithmetic unit sequentially performs a one-dimensional Fourier transform on the time variable and a one-dimensional Fourier transform on the frequency for the data output from the detection unit.
The observation apparatus according to claim 14. A lens disposed between the light source unit and the detection unit;
The light receiving surface of the detection unit is an imaging surface on which an image of the object is formed in the first direction by the lens, and a surface on which a Fresnel diffraction image of the object is formed in the second direction. Arranged,
Before Symbol lenses have row one-dimensional Fourier transform for the first direction,
The arithmetic unit sequentially performs a one-dimensional Fourier transform on the time variable and a one-dimensional Fourier transform on the frequency for the data output from the detection unit.
The observation apparatus according to claim 14. The calculation unit further includes an initial phase correction unit that corrects an initial phase included in data obtained by one-dimensional Fourier transform regarding the time variable.
The observation apparatus according to any one of claims 1 to 17. There are a plurality of the detection units,
The calculation unit further includes an output totalizer that calculates a sum of outputs from the plurality of detection units.
The observation apparatus according to any one of claims 1 to 18. The calculation unit further includes a second direction conversion unit that performs Fourier transformation or Fresnel transformation on the second direction,
The observation apparatus according to any one of claims 1 to 19. Among the data obtained by the one-dimensional Fourier transform relating to the time variable, the calculation unit is configured to obtain the data of the region including the Nyquist frequency around the difference frequency between the first modulation frequency and the second modulation frequency. Dimensional Fourier transform,
Observation device according to any one of claims 1 to 1 3. Among the data obtained by the one-dimensional Fourier transform relating to the time variable, the arithmetic unit is configured to obtain the frequency of data in a region including the Nyquist frequency around the difference frequency between the first modulation frequency and the second modulation frequency. Performing a one-dimensional Fourier transform on the first direction and a one-dimensional Fourier transform on the first direction,
The observation apparatus according to any one of claims 14 to 20. The modulator is configured as one modulator,
Among the data obtained by the one-dimensional Fourier transform relating to the time variable, the arithmetic unit, about data in a region including the Nyquist frequency around the modulation frequency in the one modulator or a harmonic of the modulation frequency, Performing the two-dimensional Fourier transform;
Observation device according to any one of claims 1 to 1 3. The modulator is configured as one modulator,
Among the data obtained by the one-dimensional Fourier transform relating to the time variable, the arithmetic unit, about data in a region including the Nyquist frequency around the modulation frequency in the one modulator or a harmonic of the modulation frequency, Performing a one-dimensional Fourier transform on the frequency and a one-dimensional Fourier transform on the first direction;
The observation apparatus according to any one of claims 14 to 20. A speed detector for detecting the moving speed of the object;
Based on the speed of the object detected by the speed detection unit, the calculation unit performs correction related to the speed change of the object during the one-dimensional Fourier transform or the two-dimensional Fourier transform related to the time variable.
The observation apparatus according to any one of claims 1 to 13 .   The observation apparatus according to any one of claims 1 to 25, wherein the light irradiation to the object is an optical arrangement of transmitted illumination.   The observation apparatus according to any one of claims 1 to 25, wherein the light irradiation to the object is an optical arrangement of reflected illumination.   The observation device according to any one of claims 1 to 27, wherein the light source unit is a light source that generates light in a single longitudinal mode.   The observation apparatus according to claim 1, wherein the light source unit is a light source that generates broadband light.   The observation device according to claim 29, wherein the light source unit is a mode-locked laser.   The said detector is further arrange | positioned in the front surface of the said light-receiving surface, The light from the said light source part is interrupted | blocked, The filter which further permeate | transmits the fluorescence produced from the said target object is provided. Observation device.