JP2009031230A - Method for displaying measurement data - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To actualize a method for visibly displaying measurement data in order to allow the data to be intuitively acquired in an interactive way on a real time basis while changing parameters, the measurement data being acquired through measurement using a measurement apparatus, etc. such as an OCT device. <P>SOLUTION: As to two-dimensional image data with a center acquired from a photodetector of a polarization-sensitive optical coherence tomograph, their values (parameters) in a circumferential direction (coordinate) are expressed by means of lines using distances from the center as parameters wherein values, distributed circumferentially or like a doughnut, are superposed on a two-dimensional image with distances from a center set as values (parameters) in a two-dimensional plane. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for displaying measurement data used in a measuring instrument (eg, an optical coherence tomography apparatus or the like).

  Conventionally, as one of non-destructive tomographic measurement techniques for various objects to be measured, there is an optical tomographic imaging apparatus “optical coherence tomography” (OCT) (see Patent Document 1). Since OCT uses light as a measurement probe, it has the advantage that it can measure the refractive index distribution, spectral information, polarization information (birefringence distribution), etc. of the measured object.

  The basic OCT 43 is based on a Michelson interferometer, and its principle will be described with reference to FIG. The light emitted from the light source 44 is collimated by the collimator lens 45 and then divided into reference light and object light by the beam splitter 46. The object light is condensed on the measurement object 48 by the objective lens 47 in the object arm, scattered and reflected there, and then returns to the objective lens 47 and the beam splitter 46 again.

  On the other hand, the reference light passes through the objective lens 49 in the reference arm, is reflected by the reference mirror 50, and returns to the beam splitter 46 through the objective lens 49 again. The object light and the reference light that have returned to the beam splitter 46 in this way are incident on the condensing lens 51 together with the object light and are collected on the photodetector 52 (photodiode or the like).

  The light source 44 of the OCT uses a light source of light having low temporal coherence (light emitted from the light source at different times is extremely difficult to interfere with each other). In a Michelson interferometer using temporally low coherence light as a light source, an interference signal appears only when the distance between the reference arm and the object arm is approximately equal. As a result, when the intensity of the interference signal is measured by the photodetector 52 while changing the optical path length difference (τ) between the reference arm and the object arm, an interference signal (interferogram) for the optical path length difference is obtained.

  The shape of the interferogram shows the reflectance distribution in the depth direction of the measurement object 48, and the structure in the depth direction of the measurement object 48 can be obtained by one-dimensional axial scanning. Thus, in the OCT 43, the structure in the depth direction of the measurement object 48 can be measured by optical path length scanning.

  In addition to the scanning in the axial direction, a two-dimensional cross-sectional image of the object to be measured can be obtained by performing a two-dimensional scanning by adding a horizontal mechanical scanning. The scanning device that performs the horizontal scanning includes a configuration in which the object to be measured is directly moved, a configuration in which the objective lens is shifted while the object is fixed, and a pupil of the objective lens while the object to be measured and the objective lens are fixed. The structure etc. which rotate the angle of the galvanometer mirror in the surface vicinity are used.

  As the development of the basic OCT described above, a spectral domain OCT (SD-OCT) that obtains a spectrum signal using a spectroscope, and a wavelength scanning OCT (Swept Source) that obtains a spectrum interference signal by scanning the wavelength of the light source. OCT, abbreviated as “SS-OCT”). SD-OCT includes Fourier domain OCT (Fourier Domain OCT, abbreviated as “FD-OCT”; see Patent Document 2), and polarization-sensitive OCT (Polarization-Sensitive OCT, abbreviated as “PS-OCT”). Reference 3).

  In the Fourier domain OCT, the wavelength spectrum of the reflected light from the object to be measured is acquired with a spectrometer (spectrum spectrometer), and Fourier transform is performed on this spectrum intensity distribution, so that the real space (OCT signal space) is obtained. This Fourier domain OCT does not need to scan in the depth direction, and can measure the cross-sectional structure of the object to be measured by scanning in the x-axis direction.

  The wavelength scanning type OCT obtains a three-dimensional optical tomographic image by changing the wavelength of a light source by a high-speed wavelength scanning laser, rearranging interference signals using a light source scanning signal acquired in synchronization with a spectrum signal, and applying signal processing. Is. As a means for changing the wavelength of the light source, a device using a monochromator can be used as the wavelength scanning OCT.

JP 2002-310897 A JP 11-325849 A JP 2004-028970 A

  Conventionally, an OCT apparatus measures the structure of a sample having birefringence, and also requires various technical fields that require high-precision resolution in the depth direction of the sample, for example, industrial fields such as manufacturing of semiconductor products, animal Research and observation field of animals and plants such as biological observation and plant structure observation, field of analysis and appraisal technology of various cultural assets, robot technology field (observing each part organ such as plants, insects, animals, etc. This is useful for applications to robot technology).

  By the way, if the obtained data can be displayed intuitively, it is useful because the structure of the object can be analyzed and understood more easily and intuitively. However, there has been no such technique in the past. The present invention visually displays measurement data obtained by measurement with a measuring instrument such as an OCT apparatus as described above so that the data can be intuitively grasped in real time while changing parameters. To achieve this method.

  In order to solve the above-mentioned problem, the present invention can display a line with a distance from the center as a parameter by superimposing a value distributed in a circle or donut shape on a two-dimensional image having a center detected by a measuring instrument. A method for displaying measurement data is provided.

  According to the measurement data display method according to the present invention having the above-described configuration, the value (parameter) in the circumferential direction (coordinates) of two-dimensional data having a center (axis) is represented in a two-dimensional plane. It is possible to understand more intuitively by overlapping and displaying with a line with the distance from the center as a value (parameter). This display method is not limited to the display of the OCT measurement signal, but is useful as another general data display method.

  The best mode for carrying out the measurement data display method according to the present invention will be described below with reference to the drawings based on the embodiments.

  In the first embodiment, an example in which the measurement data display method according to the present invention is applied to a polarization-sensitive optical coherence tomography apparatus will be described.

  As described in the “Background Art” section, in the optical coherence tomography apparatus (OCT), the beam from the light source is sent separately to the reference arm and the sample arm, and in the sample arm, the depth direction (A The sample is irradiated in a direction perpendicular to (direction) (B-scan), and an AB image is obtained from the interference spectrum between the reflected light and the reference light reflected from the reference arm (performs OCT measurement). The present invention is applied to FD-OCT (Fourier domain OCT) and the like.

  Supplementally, scanning in the depth (optical axis) direction of the sample (this scanning is referred to as “A-scan”, and this direction is also referred to as “A-direction”, “A scan direction”) is performed once. This is possible by acquiring backscattering data in the depth direction by light irradiation. Scanning in the lateral direction (direction perpendicular to the A direction) by a galvano mirror (this scanning is called “B-scan”). By performing “B-direction” and “B-scan direction”), a two-dimensional tomographic image (polarization-sensitive OCT image) can be obtained.

  The polarization-sensitive optical coherence tomography apparatus to which the measurement data display method according to the present invention is applied, EO-modulates a polarized beam (a beam linearly polarized by a polarizer) from a light source simultaneously (synchronously) with a B-scan. The light is continuously modulated by a detector (polarization modulator, electro-optic modulator), the polarized light beam whose polarization is continuously modulated is divided, one is scanned as an incident beam, and the sample is irradiated, and the reflected light (object) Light) and OCT measurement is performed by spectral interference between them using the other as reference light.

  Of the spectral interference components, the vertical polarization component (H) and the horizontal polarization component (V) are simultaneously measured by two photodetectors, thereby obtaining a Jones vector representing the polarization characteristics of the sample (H image and V). Image) structure.

  FIG. 1 is a diagram showing an overall configuration of an optical system of a polarization-sensitive optical coherence tomography apparatus to which a measurement data display method according to the present invention is applied. 1 includes optical elements such as a light source 2, a polarizer 3, an EO modulator 4, a fiber coupler (optical coupler) 5, a reference arm 6, a sample arm 7, a spectroscope 8, and the like. ing. The optical system of this polarization-sensitive received light image measuring apparatus 1 may have a structure of a type (free space type) in which optical elements are coupled to each other by a fiber 9 but not coupled to a fiber.

  The light source 2 uses a super luminescent diode (SLD) having a broadband spectrum. The light source 2 may be a pulse laser. The light source 2 includes a collimating lens 11, a polarizer 3 that linearly polarizes light from the light source 2, an EO modulator 4 with a fast axis set in a 45 ° direction, and a condenser lens 13 (in some cases, a further lens 13 ′ is used) and the fiber coupler 5 are connected in sequence.

  The EO modulator 4 fixes the fast axis in a 45 ° direction and modulates the voltage applied to the EO modulator 4 sinusoidally, so that the phase between the fast axis and the slow axis orthogonal thereto is obtained. The phase difference (retardation) is continuously changed. As a result, when light that has been emitted from the light source 2 and changed into (longitudinal) linearly polarized light by the polarizer 3 is incident on the EO modulator 4, the light is linearly changed at the above-described modulation period. Polarized light → elliptical polarized light → linearly polarized light, etc. As the EO modulator 4, a commercially available EO modulator may be used.

  A reference arm 6 and a sample arm 7 are connected to the fiber coupler 5 via a branching fiber 9. The reference arm 6 is sequentially provided with a polarization controller 10, a collimating lens 11, a polarizer 12, a condenser lens 13, and a reference mirror (fixed mirror) 14. The polarizer 12 of the reference arm 6 is used to select a direction in which the intensity of light returning from the reference arm 6 does not change even when the polarization state is modulated as described above. Adjustment of the direction of the polarizer 12 (polarization direction of linearly polarized light) is performed as a set with the polarization controller 10.

  In the sample arm 7, a polarization controller 15, a collimator lens 11, a fixed mirror 24, a galvano mirror 16, and a condenser lens 13 are sequentially provided, and an incident beam from the fiber coupler 5 is scanned by a biaxial galvano mirror 16. The sample 17 is irradiated. The reflected light (backscattered light) from the sample 17 returns to the fiber coupler 5 again as object light, is superimposed on the reference light, and sent to the spectrometer 8 as an interference beam.

  The spectroscope 8 includes a polarization controller 18, a collimator lens 11, a (polarization-sensitive volume phase holographic) diffraction grating 19, a Fourier transform lens 20, a polarization beam splitter 21, and two photodetectors 22 and 23 that are sequentially connected. I have. In this embodiment, a line CCD camera (one-dimensional CCD camera) is used as the photodetectors 22 and 23. The interference beam sent from the fiber coupler 5 is collimated by the collimating lens 11 and dispersed into an interference spectrum by the diffraction grating 19.

  The interference spectrum beam dispersed by the diffraction grating 19 is Fourier transformed by a Fourier transform lens 20 and divided into horizontal and vertical components by a polarization beam splitter 21 and detected by two line CCD cameras (photodetectors) 22 and 23, respectively. The Since the two line CCD cameras 22 and 23 are used to detect the phase information of both the horizontal and vertical polarization signals, the two line CCD cameras 22 and 23 do not contribute to the formation of the same spectrometer. must not.

  The light source 2, the reference arm 6, the sample arm 7, and the spectrometer 8 are provided with polarization controllers 10, 15, and 18, respectively. The initial polarization state of each beam sent to the device 8 is adjusted so that the polarization state continuously modulated by the EO modulator 4 has a constant amplitude and a constant relative polarization state in the reference light and the object light. The relationship is maintained, and the spectroscope 8 connected to the fiber coupler 5 is controlled so as to maintain a constant amplitude and a constant relative polarization state.

  When the spectroscope 8 including the two line CCD cameras 22 and 23 is calibrated, the EO modulator 4 is stopped. The reference light is blocked, and the slide glass and the reflecting mirror are placed on the sample arm 7. This arrangement ensures that the positions of the peaks of the horizontal and vertical polarization components are the same. The OCT signals from the rear surface of the slide glass and the reflecting mirror are detected by the two spectrometers 8. The phase difference of the peak of the OCT signal is monitored.

  This phase difference should be zero at all optical axis depths. The signal is then windowed and inverse Fourier transformed to obtain a complex spectrum with a spectrometer 8 that includes two line CCD cameras 22,23. Since this phase difference should be zero at all frequencies, by monitoring these values, the physical positions of the two line CCD cameras 22, 23 are aligned so that the phase difference is minimized.

  The operation of the polarized light-sensitive received image measuring device is as follows. The light from the light source 2 is linearly polarized, and the linearly polarized beam is continuously modulated in the polarization state by the EO modulator 4. That is, the EO modulator 4 fixes the fast axis in a 45 ° direction and modulates the voltage applied to the EO modulator 4 sinusoidally, so that the phase between the fast axis and the slow axis orthogonal thereto is obtained. The phase difference (polarization angle: retardation) of the light is continuously changed, so that when the light that has been emitted from the light source 2 and converted into (longitudinal) linearly polarized light by the linear polarizer enters the EO modulator 4, In a cycle, the light is modulated as follows: linearly polarized light → elliptical polarized light → linearly polarized light.

  The linearly polarized polarized beam is continuously modulated in the polarization state by the EO modulator 4, and at the same time, the B scan is performed in synchronization. That is, during one B scan, the EO modulator 4 continuously modulates the polarization for a plurality of periods. Here, one period is a period during which the polarization angle (retardation) φ changes from 0 to 2π. In short, during this one cycle, the polarization of light from the polarizer is continuously modulated as linearly polarized light (vertical polarized light) → elliptical polarized light → linearly polarized light (horizontal polarized light).

  In this way, while continuously modulating the polarization of the polarized beam, the sample arm 7 scans the incident beam on the sample 17 by the galvano mirror 16 to perform the B scan, and the spectroscope 8 performs the object light as the reflected light. As for the interference spectrum of the reference light, the horizontal polarization component and the vertical polarization component are detected by the two line CCD cameras 22 and 23. Thus, two AB scan images corresponding to the horizontal polarization component and the vertical polarization component are obtained by one B scan.

  As described above, during one B-scan, continuous modulation of the polarization of the polarized beam is performed for a plurality of periods, but the two line CCD cameras 22 and 23 are continuously modulated during each period (one period). The polarization information of each of the horizontal polarization component and the vertical polarization component detected in step 1 becomes polarization information for one pixel. Polarization information is synchronized with the detection timing signal by two line CCD cameras 22 and 23 during one period of continuous modulation, and the number of detections (number of acquisitions) is four times, eight times, etc. What is necessary is just to decide suitably.

  Two-dimensional AB scan image data obtained during one B scan in this way is subjected to a one-dimensional Fourier transform in the B scan direction. Then, 0th, 1st and −1st order peaks appear. Here, when 0th-order peaks are extracted and inverse Fourier transform is performed using only the data, H0 and V0 images are obtained. Similarly, H1 and V1 images are obtained by extracting primary peaks and performing inverse Fourier transform using only the data.

  From the H0 and H1 images, J (1,1) and J (1,2) can be obtained from the Jones matrix components of the equation (see equation (18) below) which is the polarization characteristic of the sample 17. From the V0 and V1 images, J (2,1) and J (2,2) among the components of the Jones matrix of the expression (1), which is the polarization characteristic of the sample 17, can be obtained.

  In this way, information including four polarization characteristics can be obtained for one B-scan. Then, when these four pieces of information are Fourier-transformed in the A-scan direction in the same manner as in ordinary FD-OCT, the primary peak has information in the depth direction of the sample 17, and each 4 corresponds to the polarization characteristic. A sheet of AB image is obtained.

  By the way, in the polarization-sensitive optical coherence tomography apparatus, the polarization state of incident light is such as linearly polarized light (vertical polarized light) → elliptical polarized light → linearly polarized light (horizontal polarized light) in order to embed the polarization information during the horizontal B scan. Continuously or three-step modulated.

  OCT signals including phase information are obtained by Fourier transforming the respective light intensity signals detected by the two CCD cameras 22 and 23. The 0th-order and 1st-order frequency components of this OCT signal are taken out and inverse Fourier transformed respectively. Using these values, all the elements of the Jones matrix representing the polarization properties of the sample are obtained. Finally, the phase retardation amount (birefringence amount), the relative orientation distribution (direction) of birefringence, and dichroism, which are values representing the physical polarization dependence of the sample, are calculated.

(Display means)
By the way, in a three-dimensional image of an OCT image, a plane perpendicular to the optical axis (a plane perpendicular to the A scan direction, a plane including the B scan and C scan directions) is referred to as an “en face”. Therefore, the en face phase delay map is a two-dimensional image of the phase delay observed from the optical axis direction.

  The measurement data display method according to the present invention is a signal processing apparatus (specifically, a computer) that acquires a phase delay amount from an image signal obtained by the polarization-sensitive optical coherence tomography apparatus as described above. The method is characterized in that display data indicating the delay amount is formed and displayed as two-dimensional image data in an easy-to-understand manner.

  Hereinafter, the display method of measurement data according to the present invention will be described in detail. For convenience of explanation, an image signal of an eye obtained by a polarization-sensitive optical coherence tomography apparatus is used. Is merely listed as a “general model of measurement data”, and there is no intention to use this measurement data and its display method for human treatment.

  First, the general description of the measurement data display method according to the present invention will be described. As shown in FIG. 3, the phase delay amount is displayed as a two-dimensional image as an en face phase delay map. FIG. 4 shows the phase delay amount at the center of the two circles in FIG. 3, and the horizontal axis represents coordinates (angles) on the circumference (doughnut). The vertical axis value corresponding to each horizontal axis value is taken as the distance from the center of FIG. By displaying the polar coordinate plot superimposed on the phase delay map, the data can be grasped more intuitively.

  FIG. 5 shows what is displayed by superimposing the polar coordinate phase delay amount on the en face phase delay map, and the cumulative phase delay distribution can be intuitively displayed. This polar coordinate plot shows the en face phase delay distribution and represents a typical curve of the phase delay of the ring-shaped area.

  Hereinafter, each display example of the display method of the measurement data according to the present invention will be described. Here, the object is an eye, but for the convenience of description, the display method of the measurement data according to the present invention is used. For example, in order to explain that useful data can be displayed visually and intuitively, the eyes are given as a general model of the object. The display method of measurement data according to the present invention is not a technical idea that forms part of a human treatment method, but is merely a display method of display data of measurement data, not a human treatment method.

  As in the case of the general description, the phase delay amount is displayed as a two-dimensional image as a layer thickness map of the fundus as shown in FIG. The layer thickness of the fundus on the circumference is taken as the distance from the center, and is connected by a one-segment line (polar coordinate plot fundus layer thickness). Similarly to the above, as shown in FIG. 5, the polar coordinate plot is displayed on the fundus layer thickness map so that the data can be grasped more intuitively.

  The present invention forms display data as described below in a signal processing device (specifically, a computer) that acquires a retinal thickness from an image signal obtained by a polarization-sensitive optical coherence tomography device, and is useful. It is a way that data can be displayed.

  The phase delay amount is displayed as a two-dimensional image as a retinal thickness map, as shown in FIG. 3, as in the case of the general description. The reticulated film thickness on the circumference is taken as the distance from the center, and is connected by a one-segment line (polar coordinate plot reticulated film thickness). Similar to the above, as shown in FIG. 5, by displaying the polar coordinate plot superimposed on the retinal thickness map, the data can be grasped more intuitively.

  The present invention forms display data as described below in a signal processing device (specifically, a computer) that acquires the fundus IS / OS thickness from an image signal obtained by a polarization-sensitive optical coherence tomography device. In this way, useful data can be displayed.

  As in the case of the above general explanation, the phase delay amount is determined as shown in FIG. 3 by the thickness of the inner membrane (IS) and the outer membrane (OS) constituting the retinal photoreceptor (IS / OS thickness) is displayed as a two-dimensional image. The IS / OS thickness of the fundus on the circumference is taken as the distance from the center, and is connected by a single line (polar coordinate plot fundus IS / OS thickness). Similar to the above, as shown in FIG. 5, the polar coordinate plot is displayed on the fundus IS / OS thickness map so that the data can be grasped more intuitively.

  The present invention forms display data as described below in a signal processing device (specifically, a computer) that acquires the choroid thickness from the image signal obtained by the polarization-sensitive optical coherence tomography device, It is a method that can display useful data.

  The phase delay amount is displayed as a two-dimensional image as a choroid thickness map, as shown in FIG. 3, as in the case of the general description. The choroidal film thickness on the circumference is taken as the distance from the center, and is connected by a one-segment line (polar coordinate plot choroidal film thickness). Similar to the above, as shown in FIG. 5, by displaying the polar coordinate plot superimposed on the choroid thickness map, the data can be grasped more intuitively.

  The present invention forms display data as described below in a signal processing device (specifically, a computer) that acquires fundus optic nerve fiber thickness from an image signal obtained by a polarization-sensitive optical coherence tomography device, It is a method that can display useful data.

  The phase delay amount is displayed as a fundus optic nerve fiber thickness map as a two-dimensional image, as shown in FIG. 3, as in the case of the general description. The thickness of the fundus optic nerve fiber on the circumference is taken as a distance from the center, and is connected by a one-segment line (polar coordinate plot fundus optic nerve fiber thickness). Similarly to the above, as shown in FIG. 5, the polar coordinate plot is displayed on the fundus optic nerve fiber thickness map so that the data can be grasped more intuitively.

  The present invention forms display data as described below in a signal processing device (specifically, a computer) that acquires the orientation of fundus birefringence from an image signal obtained by a polarization-sensitive optical coherence tomography device. It is a method that can display useful data.

  The phase delay amount is displayed as a two-dimensional image as an orientation map of fundus birefringence, as shown in FIG. 3, as in the case of the general description. The azimuth of the fundus birefringence on the circumference is taken as the distance from the center, and is connected by a one-segment line (polar coordinate plot fundus birefringence). Similar to the above, as shown in FIG. 5, the polar coordinate plot is displayed on the orientation map of the fundus birefringence so that the data can be grasped more intuitively.

INDUSTRIAL APPLICABILITY The present invention forms display data as described below and is useful in a signal processing device (specifically, a computer) that acquires a corner angle from an image signal obtained by a polarization-sensitive optical coherence tomography device. It is a method that can display various data.

  The phase delay amount is displayed as a two-dimensional image as a corner angle map, as shown in FIG. 3, as in the case of the general description. The corner angle on the circumference is taken as the distance from the center, and is connected by a one-segment line (polar plot corner angle). Similarly to the above, as shown in FIG. 5, the polar coordinate plot is displayed on the corner angle map so that the data can be grasped more intuitively.

  In the present invention, AOD (Angle Opening Distance, a distance from the point of 500 μm or 750 μm vertically from the scleral cape on the back of the cornea, the distance to the iris) is obtained from the image signal obtained by the polarization-sensitive optical coherence tomography apparatus In a signal processing apparatus (specifically, a computer) for acquiring a corner angle parameter, display data as described below can be formed and useful data can be displayed.

  As in the case of the general description, the phase delay amount is displayed as a two-dimensional image as a general corner parameter map such as AOD as shown in FIG. A general corner parameter such as AOD on the circumference is taken as a distance from the center, and is connected by a one-segment line (general corner parameter such as polar coordinate plot AOD). Similar to the above, as shown in FIG. 5, the polar coordinate plot is displayed on a general corner parameter map such as AOD and displayed, so that the data can be grasped more intuitively.

  The present invention forms display data as described below in a signal processing device (specifically, a computer) that acquires a corner adhesion amount from an image signal obtained by a polarization-sensitive optical coherence tomography device, It is a method that can display useful data.

  As in the case of the general description, the phase delay amount is displayed as a corner adhesion amount map as a two-dimensional image as shown in FIG. Take the corner adhesion amount on the circumference as the distance from the center and connect with a one-segment line (polar coordinate corner adhesion amount). Similarly to the above, as shown in FIG. 5, the polar coordinate plot is displayed on the corner adhesion amount map so that the data can be grasped more intuitively.

  The present invention forms display data as described below in a signal processing apparatus (specifically, a computer) that acquires corneal thickness from an image signal obtained by a polarization-sensitive optical coherence tomography apparatus, and is useful. It is a way that data can be displayed.

  The phase delay amount is displayed as a corneal thickness map as a two-dimensional image as shown in FIG. 3 as in the case of the general description. The corneal thickness on the circumference is taken as the distance from the center, and is connected by a one-segment line (polar coordinate plot corneal thickness). Similarly to the above, as shown in FIG. 5, the polar coordinate plot is displayed on the corneal thickness map so that the data can be grasped more intuitively.

  The display means and method are not limited to the display of the OCT signal. Generally, for the two-dimensional data having the center (axis), the value (parameter) in the circumferential direction (coordinate) is set in the two-dimensional plane. It is possible to understand more interactively in real time while changing the parameters by overlapping the distance from the center with a line with the value (parameter). The present invention is applied as a general data display means and method.

  The best mode for carrying out the present invention has been described based on the embodiments. However, the present invention is not limited to such embodiments, and within the scope of the technical matters described in the claims. Needless to say, there are various embodiments. The method for displaying measurement data according to the present invention can be applied not only to a polarization-sensitive optical coherence tomography apparatus, but also to a polarization-sensitive spectral domain OCT apparatus (PS-SD-OCT) or a polarization-sensitive wavelength scanning OCT apparatus ( (PS-SS-OCT) is also applicable.

  Since the measurement data display method according to the present invention is configured as described above, various technical fields are required in which the structure of a sample having birefringence is measured and high-precision resolution is required in the depth direction of the sample. , For example, industrial fields such as manufacturing of semiconductor products, animal / plant research and observation fields such as animal living body observations and plant structure observations, various cultural property analysis / appraisal technology fields, robot technology fields (plants, insects, It is useful for OCT for optical tomographic image acquisition, such as medical examination equipment, for observing various organs such as animals and applying their structures and functions to robot technology.

It is a figure explaining the whole structure of the polarization sensitive optical coherence tomography apparatus to which the display method of measurement data concerning the present invention is applied. It is a figure explaining the prior art example (the principle of OCT). It is the figure which displayed the phase delay amount by the two-dimensional image as an en face phase delay map. FIG. 4 is a diagram showing a phase delay amount at the center of two circles in FIG. 3. en face It is the figure which displayed the polar-coordinate plot phase delay amount superimposed on the phase delay map.

Explanation of symbols

1 Polarized light receiving image measuring device
2 Light source
3, 12 Polarizer
4 EO modulator (polarization modulator, electro-optic modulator)
5 Fiber coupler (optical coupler)
6 Reference arm
7 Sample arm
8 Spectrometer
9 Fiber
10, 15, 18 Polarization controller
11 Collimating lens
13 Condensing lens
14 Reference mirror (fixed mirror)
16 Galvano mirror
17 samples
19 Diffraction grating
20 Fourier transform lens
21 Polarizing beam splitter
22, 23 Photodetector (Line CCD camera)
24 fixed mirror

Claims (1)

  Display of measurement data, characterized in that a two-dimensional image with a center detected by a measuring device is superimposed on a value distributed in a circle or donut shape, and can be displayed as a line with the distance from the center as a parameter Method.