Optical tomography imaging device

Abstract

To provide a technology to reduce a burden on a subject and an examiner when executing a plurality of kinds of examinations.SOLUTION: An optical tomographic imaging apparatus includes: an imaging unit for taking a tomographic image of an eye to be examined; instruction means for giving an instruction on a kind of examination report indicating a desired examination result; storage means for storing a control program for causing the imaging unit to execute imaging for creating the kind of examination report for each of the kinds of examination reports; and a control unit for, when the instruction means gives instructions for a plurality of kinds of examination reports, controlling the imaging unit according to a series of control programs created on the basis of the plurality of kinds of corresponding control programs stored in the storage means.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The technology disclosed in this specification relates to an optical tomographic imaging apparatus. [Background technology]

[0002] An optical tomographic imaging apparatus for acquiring a tomographic image of a subject's eye has been developed. The optical tomographic imaging apparatus includes a measurement optical system that irradiates light from a light source onto the subject's eye and guides the reflected light, and a reference optical system that irradiates light from the light source onto a reference surface and guides the reflected light. During measurement, a tomographic image of the subject's eye is generated from interference light obtained by combining the reflected light (measurement light) guided by the measurement optical system and the reflected light (reference light) guided by the reference optical system. In such an optical tomographic imaging apparatus, in order to acquire an image including a desired examination result, it is necessary to set the imaging conditions such as a scan pattern during imaging as necessary. For example, in the optical tomographic imaging apparatus of Patent Document 1, imaging conditions (i.e., operation modes) corresponding to the type of examination are set in advance. The examiner selects an operation mode suitable for the desired examination. Then, the optical tomographic imaging apparatus images the subject's eye under imaging conditions corresponding to the selected operation mode, analyzes the imaging results, and outputs the examination results corresponding to the selected operation mode. Therefore, the examiner can acquire the examination results corresponding to the operation mode by selecting an operation mode without setting the imaging conditions in detail. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-24930 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the optical tomographic imaging apparatus of Patent Document 1, if an examiner selects an operation mode, an image is captured under imaging conditions corresponding to the operation mode, and a report showing an examination result corresponding to the operation mode is generated. That is, in the optical tomographic imaging apparatus of Patent Document 1, an operation mode is associated with a corresponding imaging condition and a corresponding examination report. Therefore, when performing multiple types of examinations on an examinee's eye, imaging is performed under imaging conditions corresponding to one operation mode, and then imaging is performed under imaging conditions corresponding to the next different operation mode. Therefore, when performing multiple types of examinations, it is necessary to repeat the operation for imaging as many times as the types of examinations, and the burden on both the examinee and the examiner increases due to the repeated imaging.

[0005] The present specification discloses a technique for reducing the burden on subjects and examiners when performing multiple types of tests. [Means for solving the problem]

[0006] The optical tomographic imaging device disclosed in this specification comprises an imaging unit that captures a tomographic image of the test eye, an instruction means that indicates the type of examination report showing the desired examination result, a memory means that stores a control program for causing the imaging unit to perform imaging to generate an examination report of that type for each type of examination report, and a control unit that, when there are multiple types of examination reports instructed by the instruction means, controls the imaging unit in accordance with a series of control programs generated based on the corresponding multiple types of control programs stored in the memory means.

[0007] In the above optical tomographic imaging apparatus, when multiple types of examination reports are instructed, a series of control programs are generated based on the control programs corresponding to the multiple types of examination reports instructed. Since the imaging unit is controlled according to this series of control programs, even when multiple types of examination reports are to be generated, imaging is performed at once by the series of control programs. Therefore, it is not necessary to perform separate operations for imaging the same number of times as the types of examination reports to be generated, and the burden on both the subject and the examiner can be reduced.

[0008] The optical tomographic imaging device disclosed in this specification comprises an imaging unit that captures a tomographic image of the test eye, a memory means that stores a control program for causing the imaging unit to perform imaging that can generate multiple types of examination reports, a control unit that causes the imaging unit to perform imaging in accordance with the control program stored in the memory means, an instruction means that indicates at least one of the multiple types of examination reports that can be generated by the imaging, and a generation unit that generates the examination report instructed by the instruction means based on specific imaging data included in a group of imaging data obtained by the control unit causing the imaging unit to perform imaging in accordance with the control program.

[0009] In the optical tomographic imaging apparatus, the control unit causes the imaging unit to perform imaging according to a control program for causing the imaging unit to perform one imaging operation capable of generating a plurality of types of examination reports. Therefore, imaging data capable of generating a plurality of types of examination reports can be acquired by one imaging operation. As a result, regardless of which of the plurality of types of examination reports is instructed, the generating unit can generate any of the plurality of types of examination reports. For example, even if it is determined that another examination report is necessary after checking a certain examination report, it is not necessary to perform imaging for generating the other examination report. Therefore, it is not necessary to repeat the imaging operation many times, and it is possible to reduce the burden on both the subject and the examiner. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of an optical system of an optical tomographic imaging apparatus according to first and second embodiments. [Diagram 2] FIG. 2 is a block diagram showing a control system of the optical tomographic imaging apparatus according to the first and second embodiments. [Diagram 3] FIG. 1 is a block diagram showing the configuration of a sampling trigger / clock generator. [Figure 4] 5 is a flowchart showing an example of a process for generating an inspection report in the first embodiment. [Diagram 5]13 is an image showing an example of an inspection report selection screen. [Figure 6] 11A and 11B are diagrams showing an example of types of inspection reports and corresponding imaging steps and details of settings. [Figure 7] An image showing a polarization map as an example of an inspection report. [Figure 8] 13 is an image showing another example of an examination report, a macular map. [Figure 9] 13 is an image showing a glaucoma map, which is another example of an examination report. [Figure 10] 13 is a flowchart showing an example of a process for generating an inspection report in the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The main features of the embodiments described below are listed below. Note that the technical elements described below are independent technical elements that exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing.

[0012] (Feature 1) In the optical tomographic imaging apparatus disclosed in the present specification, the examination report may include a first examination report showing a first examination result and a second examination report showing a second examination result. The first control program corresponding to the first examination report may include a specific imaging step. The second control program corresponding to the second examination report may include a specific imaging step. When the instruction means instructs the first examination report and the second examination report, the control unit may omit a specific imaging step included in one of the first control program and the second control program and generate a series of control programs. With this configuration, when the first examination report and the second examination report are generated, it is possible to omit redundant execution of a specific imaging step that overlaps between the first examination report and the second examination report. Therefore, it is possible to shorten the time required for imaging to generate the first examination report and the second examination report, and to reduce the burden on the subject.

[0013] (Feature 2) In the optical tomographic imaging device disclosed in this specification, the control unit may generate an examination report of a type based on imaging data captured by executing an imaging step corresponding to the type of examination report from among a group of imaging data obtained by executing a series of control programs for each type of examination report. According to this configuration, an examination report is generated using appropriate imaging data for each examination report from among the group of imaging data obtained by executing a series of control programs. For example, the group of imaging data obtained by executing a series of control programs may include imaging data necessary to generate a certain examination report as well as imaging data unnecessary for generating the examination report. By using appropriate imaging data for each examination report, each examination report can be generated appropriately.

[0014] (Feature 3) The optical tomographic imaging apparatus disclosed in this specification may further include an output unit that outputs multiple types of examination reports generated from imaging data captured according to a series of control programs. With this configuration, the examiner can obtain multiple types of examination reports and understand the examination results. EXAMPLES

[0015] Example 1 The optical tomography apparatus according to this embodiment is a polarization-sensitive OCT (PS-OCT) apparatus that can capture the polarization characteristics of a test object by wavelength-swept Fourier domain swept-source optical coherence tomography (SS-OCT) using a wavelength-swept light source.

[0016] As shown in Figure 1, the optical tomography apparatus of this embodiment includes a light source 11, a measurement light generating unit (21-29, 31, 32) that generates measurement light from the light of the light source 11, a reference light generating unit (41-46, 51) that generates reference light from the light of the light source 11, interference light generating units 60, 70 that generate interference light by combining reflected light from the test eye 500 generated by the measurement light generating unit with reference light generated by the reference light generating unit, and interference light detecting units 80, 90 that detect the interference light generated by the interference light generating units 60, 70.

[0017] (light source) The light source 11 is a wavelength sweep type light source, and the wavelength (wave number) of the emitted light changes at a predetermined period. Since the wavelength of the light irradiated to the subject's eye 500 changes (sweeps), the intensity distribution of the light reflected from each part in the depth direction of the subject's eye 500 can be obtained by performing Fourier analysis on a signal obtained from the interference light between the reflected light from the subject's eye 500 and the reference light.

[0018] A polarization control device 12 and a fiber coupler 13 are connected to the light source 11, and a PMFC (polarization maintaining fiber coupler) 14 and a sampling trigger / clock generator 100 are connected to the fiber coupler 13. Therefore, the light output from the light source 11 is input to each of the PMFC 14 and the sample trigger / clock generator 100 via the polarization control device 12 and the fiber coupler 13. The sampling trigger / clock generator 100 uses the light from the light source 11 to generate sampling triggers and sampling clocks for each of signal processors 83 and 93, which will be described later.

[0019] (Measurement light generation section) The measurement light generating unit (21 to 29, 31, 32) includes a PMFC 21 connected to the PMFC 14, two measurement light paths S1 and S2 branching from the PMFC 21, a polarized beam combiner / splitter 25 connecting the two measurement light paths S1 and S2, and a collimator lens 26, galvanometer mirrors 27 and 28, and a lens 29 connected to the polarized beam combiner / splitter 25. The measurement light path S1 includes an optical path length difference generating unit 22 and a circulator 23. The measurement light path S2 includes only a circulator 24. Therefore, the optical path length difference ΔL between the measurement light path S1 and the measurement light path S2 is generated by the optical path length difference generating unit 22. The optical path length difference ΔL may be set to be longer than the measurement range in the depth direction of the eye 500 to be examined. This makes it possible to prevent interference light having different optical path length differences from overlapping. The optical path length difference generating unit 22 may use, for example, an optical fiber, or an optical system such as a mirror or a prism. In this embodiment, a 1 m PM fiber is used for the optical path length difference generating unit 22. The measurement light generating unit further includes PMFCs 31 and 32. The PMFC 31 is connected to the circulator 23. The PMFC 32 is connected to the circulator 24.

[0020] One of the beams (i.e., the measurement beam) split by the PMFC 14 is input to the measurement beam generating unit (21 to 29, 31, 32). The PMFC 21 splits the measurement beam input from the PMFC 14 into a first measurement beam and a second measurement beam. The first measurement beam split by the PMFC 21 is guided to the measurement beam path S1, and the second measurement beam is guided to the measurement beam path S2. The first measurement beam guided to the measurement beam path S1 passes through the optical path length difference generating unit 22 and the circulator 23 and is input to the polarization beam combiner / splitter 25. The second measurement beam guided to the measurement beam path S2 passes through the circulator 24 and is input to the polarization beam combiner / splitter 25. The PM fiber 304 is connected to the polarization beam combiner / splitter 25 in a state rotated 90 degrees in the circumferential direction with respect to the PM fiber 302. As a result, the second measurement light input to the polarized beam combiner / splitter 25 becomes light having a polarization component orthogonal to the first measurement light. Since the optical path length difference generating unit 22 is provided in the measurement optical path S1, the first measurement light is delayed by the distance of the optical path length difference generating unit 22 with respect to the second measurement light (i.e., an optical path length difference ΔL occurs). The polarized beam combiner / splitter 25 superimposes the input first measurement light and second measurement light. The light output from the polarized beam combiner / splitter 25 (light in which the first measurement light and the second measurement light are superimposed) is irradiated onto the test eye 500 via the collimator lens 26, the galvanometer mirrors 27 and 28, and the lens 29. The light irradiated onto the test eye 500 is scanned in the xy direction by the galvanometer mirrors 27 and 28.

[0021] The light irradiated to the eye 500 is reflected by the eye 500. The light reflected by the eye 500 is scattered on the surface or inside the eye 500. The reflected light from the eye 500 passes through the lens 29, the galvanometer mirrors 28 and 27, and the collimator lens 26 in the opposite direction to the incident path, and is input to the polarized beam combiner / splitter 25. The polarized beam combiner / splitter 25 splits the input reflected light into two polarized components that are orthogonal to each other. For convenience, these are called horizontally polarized reflected light (horizontally polarized component) and vertically polarized reflected light (vertically polarized component). The horizontally polarized reflected light is guided to the measurement optical path S1, and the vertically polarized reflected light is guided to the measurement optical path S2.

[0022] The optical path of the horizontally polarized reflected light is changed by the circulator 23 and input to the PMFC 31. The PMFC 31 branches the input horizontally polarized reflected light and inputs it to the PMFCs 61 and 71. Therefore, the horizontally polarized reflected light input to the PMFCs 61 and 71 contains a reflected light component due to the first measurement light and a reflected light component due to the second measurement light. The optical path of the vertically polarized reflected light is changed by the circulator 24 and input to the PMFC 32. The PMFC 32 branches the input vertically polarized reflected light and inputs it to the PMFCs 62 and 72. Therefore, the vertically polarized reflected light input to the PMFCs 62 and 72 contains a reflected light component due to the first measurement light and a reflected light component due to the second measurement light.

[0023] (Reference light generation section) The reference light generating unit (41 to 46, 51) includes a circulator 41 connected to the PMFC 14, a reference delay line (42, 43) connected to the circulator 41, a PMFC 44 connected to the circulator 41, two reference light paths R1 and R2 branching from the PMFC 44, a PMFC 46 connected to the reference light path R1, and a PMFC 51 connected to the reference light path R2. An optical path length difference generating unit 45 is disposed in the reference light path R1. No optical path length difference generating unit is provided in the reference light path R2. Therefore, the optical path length difference ΔL′ between the reference light path R1 and the reference light path R2 is generated by the optical path length difference generating unit 45. For example, an optical fiber is used for the optical path length difference generating unit 45. The optical path length ΔL′ of the optical path length difference generating unit 45 may be the same as the optical path length ΔL of the optical path length difference generating unit 22. By making the optical path length differences ΔL and ΔL' equal, the depth positions of a plurality of interference lights described below with respect to the subject's eye 500 become the same. In other words, alignment of the plurality of tomographic images to be acquired is not required.

[0024] The other light (i.e., reference light) branched by the PMFC 14 is input to the reference light generating unit (41 to 46, 51). The reference light input from the PMFC 14 is input to the reference delay line (42, 43) through the circulator 41. The reference delay line (42, 43) is composed of a collimator lens 42 and a reference mirror 43. The reference light input to the reference delay line (42, 43) is irradiated to the reference mirror 43 via the collimator lens 42. The reference light reflected by the reference mirror 43 is input to the circulator 41 via the collimator lens 42. Here, the reference mirror 43 is movable in a direction approaching or moving away from the collimator lens 42. In this embodiment, before starting measurement, the position of the reference mirror 43 is adjusted so that the signal from the subject's eye 500 falls within the measurement range in the depth direction of the OCT.

[0025] The reference light reflected by the reference mirror 43 has its optical path changed by the circulator 41 and is input to the PMFC 44. The PMFC 44 splits the input reference light into a first reference light and a second reference light. The first reference light is guided to the reference optical path R1, and the second reference light is guided to the reference optical path R2. The first reference light is input to the PMFC 46 through the optical path length difference generating unit 45. The reference light input to the PMFC 46 is split into a first branched reference light and a second branched reference light. The first branched reference light is input to the PMFC 61 through the collimator lens 47 and the lens 48. The second branched reference light is input to the PMFC 62 through the collimator lens 49 and the lens 50. The second reference light is input to the PMFC 51 and split into a third branched reference light and a fourth branched reference light. The third branched reference light is input to the PMFC 71 through the collimator lens 52 and the lens 53. The fourth split reference light passes through a collimator lens 54 and a lens 55 and is input to a PMFC 72 .

[0026] (Interference light generation unit) The interference light generating units 60 and 70 include a first interference light generating unit 60 and a second interference light generating unit 70. The first interference light generating unit 60 includes PMFCs 61 and 62. As described above, the horizontally polarized reflected light is input from the measurement light generating unit to the PMFC 61, and the first branched reference light (light having an optical path length difference ΔL') is input from the reference light generating unit. Here, the horizontally polarized reflected light includes a reflected light component due to the first measurement light (light having an optical path length difference ΔL) and a reflected light component due to the second measurement light (light not having an optical path length difference ΔL). Therefore, in the PMFC 61, the reflected light component due to the first measurement light (light having an optical path length difference ΔL) of the horizontally polarized reflected light and the first branched reference light are multiplexed to generate the first interference light (horizontally polarized component).

[0027] Further, the vertically polarized reflected light is input to the PMFC 62 from the measurement light generating unit, and the second branched reference light (light having an optical path length difference ΔL') is input from the reference light generating unit. Here, the vertically polarized reflected light includes a reflected light component due to the first measurement light (light having an optical path length difference ΔL) and a reflected light component due to the second measurement light (light not having an optical path length difference ΔL). Therefore, in the PMFC 62, the reflected light component due to the first measurement light (light having an optical path length difference ΔL) of the vertically polarized reflected light is combined with the second branched reference light to generate a second interference light (vertically polarized component).

[0028] The second interference light generating unit 70 has PMFCs 71 and 72. As described above, the horizontally polarized reflected light is input to PMFC 71 from the measurement light generating unit, and the third branched reference light (light not having the optical path length difference ΔL′) is input from the reference light generating unit. Therefore, in PMFC 71, the reflected light component (light not having the optical path length difference ΔL) by the second measurement light out of the horizontally polarized reflected light is combined with the third branched reference light to generate the third interference light (horizontally polarized component).

[0029] Further, the vertically polarized reflected light is input to the PMFC 72 from the measurement light generating unit, and the fourth branched reference light (light having no optical path length difference ΔL') is input from the reference light generating unit. Therefore, in the PMFC 72, the reflected light component (light having no optical path length difference ΔL) by the second measurement light of the vertically polarized reflected light is multiplexed with the fourth branched reference light to generate a fourth interference light (vertically polarized component). The first interference light and the second interference light correspond to the measurement light that has passed through the measurement optical path S1, and the third interference light and the fourth interference light correspond to the measurement light that has passed through the measurement optical path S2.

[0030] (Interference light detection section) The interference light detection units 80, 90 include a first interference light detection unit 80 that detects the interference light (first interference light and second interference light) generated by the first interference light generation unit 60, and a second interference light detection unit 90 that detects the interference light (third interference light and fourth interference light) generated by the second interference light generation unit 70.

[0031] The first interference light detection unit 80 includes balanced photodetectors 81 and 82 (hereinafter, simply referred to as "detectors 81 and 82") and a signal processor 83 connected to the detectors 81 and 82. The PMFC 61 is connected to the detector 81, and the signal processor 83 is connected to the output terminal of the detector 81. The PMFC 61 splits the first interference light into two interference lights having a phase difference of 180 degrees and inputs them to the detector 81. The detector 81 performs differential amplification and noise reduction processing on the two interference lights having a phase difference of 180 degrees input from the PMFC 61, converts them into an electrical signal (first interference signal), and outputs the first interference signal to the signal processor 83. That is, the first interference signal is an interference signal HH of the horizontally polarized reflected light from the subject's eye 500 and the reference light due to the horizontally polarized measurement light. Similarly, the PMFC 62 is connected to the detector 82, and the signal processor 83 is connected to the output terminal of the detector 82. The PMFC 62 splits the second interference light into two interference lights whose phases differ by 180 degrees, and inputs them to the detector 82. The detector 82 performs differential amplification and noise reduction processing on the two interference lights whose phases differ by 180 degrees, converts them into an electrical signal (second interference signal), and outputs the second interference signal to the signal processor 83. That is, the second interference signal is an interference signal HV of the vertically polarized reflected light from the test eye 500 and the reference light due to the horizontally polarized measurement light.

[0032] The signal processor 83 includes a first signal processing unit 84 to which the first interference signal is input, and a second signal processing unit 85 to which the second interference signal is input. The first signal processing unit 84 samples the first interference signal based on a sampling trigger and a sampling clock input from a sampling trigger / clock generator 100 to the signal processor 83. The second signal processing unit 85 samples the second interference signal based on a sampling trigger and a sampling clock input from the sampling trigger / clock generator 100 to the signal processor 83. The first interference signal and the second interference signal sampled by the first signal processing unit 84 and the second signal processing unit 85 are input to a calculation unit 202 described later. A known data acquisition device (so-called DAQ) can be used for the signal processor 83.

[0033] The second interference light detection unit 90, like the first interference light detection unit 80, includes balanced photodetectors 91 and 92 (hereinafter, also simply referred to as "detectors 91 and 92") and a signal processor 93 connected to the detectors 91 and 92. The PMFC 71 is connected to the detector 91, and the signal processor 93 is connected to the output terminal of the detector 91. The PMFC 71 splits the third interference light into two interference lights with a phase difference of 180 degrees and inputs them to the detector 91. The detector 91 performs differential amplification and noise reduction processing on the two interference lights with a phase difference of 180 degrees, converts them into an electrical signal (third interference signal), and outputs the third interference signal to the signal processor 93. That is, the third interference signal is an interference signal VH of the horizontally polarized reflected light from the subject's eye 500 and the reference light due to the vertically polarized measurement light. Similarly, the PMFC 72 is connected to the detector 92, and the signal processor 93 is connected to the output terminal of the detector 92. The PMFC 72 splits the fourth interference light into two interference lights whose phases differ by 180 degrees, and inputs them to the detector 92. The detector 92 performs differential amplification and noise reduction processing on the two interference lights whose phases differ by 180 degrees, converts them into an electrical signal (fourth interference signal), and outputs the fourth interference signal to the signal processor 93. That is, the fourth interference signal is an interference signal VV of the vertically polarized reflected light of the test eye 500 from the vertically polarized measurement light and the reference light.

[0034] The signal processor 93 includes a third signal processor 94 to which the third interference signal is input, and a fourth signal processor 95 to which the fourth interference signal is input. The third signal processor 94 samples the third interference signal based on a sampling trigger and a sampling clock input from the sampling trigger / clock generator 100 to the signal processor 93. The fourth signal processor 95 samples the fourth interference signal based on a sampling trigger and a sampling clock input from the sampling trigger / clock generator 100 to the signal processor 93. The third interference signal and the fourth interference signal sampled by the third signal processor 94 and the fourth signal processor 95 are input to a calculation unit 202 to be described later. A known data acquisition device (so-called DAQ) can also be used for the signal processor 93. With this configuration, it is possible to obtain an interference signal representing four polarization characteristics of the subject's eye 500. In this embodiment, the signal processors 83 and 93 having two signal processors are used, but the present invention is not limited to this configuration. For example, one signal processor having four signal processing sections may be used, or four signal processors each having one signal processing section may be used.

[0035] Next, the configuration of the control system of the optical tomographic imaging apparatus according to the present embodiment will be described. As shown in FIG. 2, the optical tomographic imaging apparatus is controlled by a calculation device 200. The calculation device 200 is composed of a calculation unit 202, a first interference light detection unit 80, and a second interference light detection unit 90. The first interference light detection unit 80, the second interference light detection unit 90, and the calculation unit 202 are connected to the measurement unit 10. The calculation unit 202 outputs a control signal to the measurement unit 10 and drives the galvanometer mirrors 27 and 28 to scan the incident position of the measurement light on the subject's eye 500. The first interference light detection unit 80 acquires first sampling data based on the sampling clock 1 input from the measurement unit 10, using the sampling trigger 1 as a trigger, in response to the interference signals (interference signals HH and HV) input from the measurement unit 10, and outputs the first sampling data to the calculation unit 202. The calculation unit 202 performs arithmetic processing such as Fourier transform processing on the first sampling data to generate an HH tomographic image and an HV tomographic image. The second interference light detection unit 90 acquires second sampling data based on a sampling clock 2 input from the measurement unit 10 in response to the interference signal (interference signal VH and interference signal VV) input from the measurement unit 10, using a sampling trigger 2 as a trigger, and outputs the second sampling data to the calculation unit 202. The calculation unit 202 performs arithmetic processing such as Fourier transform processing on the second sampling data to generate a VH tomographic image and a VV tomographic image. Here, the HH tomographic image, the VH tomographic image, the HV tomographic image, and the VV tomographic image are tomographic images at the same position. Therefore, the calculation unit 202 can generate tomographic images of four polarization characteristics (HH, HV, VH, VV) that represent the Jones matrix of the subject's eye 500.

[0036] The calculation unit 202 also includes a memory 204. The memory 204 stores a control program for generating an examination report showing the result of a specific examination of the subject's eye 500, and a control program for performing photography corresponding to the examination report. The control program for generating the examination report is stored in the memory 204 for each type of examination report. The control program for performing photography is stored in the memory 204 for each type of examination report in association with the type of the examination report. The control program for performing photography is composed of one or more photography steps, and photography steps necessary for generating an examination report corresponding to the control program are set in advance. Specifically, the memory 204 stores the examination report name and the corresponding control program for performing photography in association with each other. Note that these control programs may be set by the examiner. That is, the examiner may set specific photography conditions for each photography step constituting the control program, and set it as a control program by associating it with the corresponding examination report name. The control program set by the examiner may also be stored in the memory 204. A specific example of the control program for performing photography including the examination report and the photography step associated therewith will be described later.

[0037] 3, the sampling trigger / clock generator 100 includes a fiber coupler 102, sampling trigger generators (140 to 152), and sampling clock generators (160 to 172). Light from the light source 11 is input to the sampling trigger generator 140 and the sampling clock generator 160 via the fiber coupler 13 and the fiber coupler 102, respectively.

[0038] (Sampling Trigger Generator) The sampling trigger generator 140 may generate a sampling trigger using, for example, an FBG (Fiber Bragg Grating) 144. As shown in FIG. 3, the FBG 144 reflects only a specific wavelength of light incident from the light source 11 to generate a sampling trigger. The generated sampling trigger is input to the distributor 150. The distributor 150 distributes the sampling trigger to a sampling trigger 1 and a sampling trigger 2. The sampling trigger 1 is input to the calculation unit 202 via a signal delay circuit 152. The sampling trigger 2 is input to the calculation unit 202 as is. The sampling trigger 1 becomes a trigger signal for the interference signals (first interference signal and second interference signal) input from the first interference light detection unit 80 to the calculation unit 202. The sampling trigger 2 becomes a trigger signal for the interference signals (third interference signal and fourth interference signal) input from the second interference light detection unit 90 to the calculation unit 202. The signal delay circuit 152 is designed so that the sampling trigger 1 is delayed in time from the sampling trigger 2 by the optical path length difference ΔL of the optical path length difference generation unit 22. This makes it possible to make the frequency at which sampling of the interference signal input from the first interference light detection unit 80 starts the same as the frequency at which sampling of the interference signal input from the second interference light detection unit 90 starts. Here, only the sampling trigger 1 may be generated. Since the optical path length difference ΔL is known, when sampling the interference input from the second interference light detection unit 90, sampling may be started so as to be delayed in time by the optical path length difference ΔL from the sampling trigger 1.

[0039] (Sampling Clock Generator) The sampling clock generator may be configured with, for example, a Mach-Zehnder interferometer. As shown in FIG. 3, the sampling clock generator generates a sampling clock with a uniform frequency using a Mach-Zehnder interferometer. The sampling clock generated by the Mach-Zehnder interferometer is input to a distributor 172. The distributor 172 distributes the sampling clock into a sampling clock 1 and a sampling clock 2. The sampling clock 1 is input to the first interference light detection unit 80 through a signal delay circuit 174. The sampling clock 2 is input directly to the second interference light detection unit 90. The signal delay circuit 174 is designed to delay the time by the optical path length difference ΔL of the optical path length difference generation unit 22. This allows sampling at the same timing even for interference light delayed by the optical path length difference generation unit 22. This prevents positional deviation of the multiple tomographic images to be acquired. In this embodiment, a Mach-Zehnder interferometer is used to generate the sampling clock. However, the sampling clock may be generated using a Michelson interferometer or an electrical circuit, or may be generated using a light source equipped with a sampling clock generator.

[0040] Next, a process of generating an examination report for the subject's eye 500 will be described with reference to Fig. 4. As shown in Fig. 4, first, the calculation unit 202 causes the monitor 120 (see Fig. 2) to display types of examination reports that can be generated by the optical tomographic imaging apparatus of this embodiment (S12). The memory 204 stores types of examination reports that can be generated by the optical tomographic imaging apparatus of this embodiment. The calculation unit 202 causes the monitor 120 to display all types of examination reports that can be generated and are stored in the memory 204.

[0041] For example, in this embodiment, it is assumed that four types of examination reports can be generated: "polarization map", "macular map", "glaucoma map", and "optical disk shape analysis". In this case, as shown in Fig. 5, the calculation unit 202 causes the monitor 120 to display the four types of examination reports, "polarization map", "macular map", "glaucoma map", and "optical disk shape analysis", in a selectable manner.

[0042] Next, the calculation unit 202 judges whether or not the type of examination report has been selected (S14). Specifically, the examiner selects an examination report corresponding to a desired examination from a plurality of examination reports displayed on the monitor 120 using an input means such as a mouse (not shown). In the example shown in FIG. 5, the examiner selects a desired examination report from "polarization map", "macular map", "glaucoma map", and "optic disc shape analysis". The number of examination reports selected by the examiner is not particularly limited. Therefore, the examiner can select a plurality of desired examination reports. For example, the examiner selects three examination reports, "polarization map", "macular map", and "glaucoma map". Then, when the examination report selection work is completed, the examiner instructs the completion of the selection work. For example, the examiner instructs the completion of the selection work by pressing an "OK" button displayed on the monitor 120 using the input means. The calculation unit 202 waits until the completion of the selection work is instructed (NO in step S14).

[0043] When completion of the selection operation is instructed (YES in step S14), the calculation unit 202 identifies the imaging step associated with the examination report selected in step S14 (S16). As described above, the memory 204 stores imaging steps required to generate the examination report, linked to the type of the examination report. The calculation unit 202 reads out the imaging step corresponding to the examination report selected in step S14 from the memory 204.

[0044] For example, as shown in Fig. 6, memory 204 stores a plurality of types of examination reports, the corresponding imaging steps, and detailed imaging conditions for the imaging steps. In the example shown in Fig. 6, the imaging step for the "polarization map" is "Cube". Therefore, calculation unit 202 specifies that the imaging step for the selected "polarization map" is "Cube". Similarly, calculation unit 202 specifies that the imaging step for the selected "macular map" is "Cube", and specifies that the imaging steps for the selected "glaucoma map" are "Cube" and "Cube Disk".

[0045] Next, the calculation unit 202 determines whether or not there is an overlap in the imaging steps identified in step S16 (S18). When multiple types of examination reports are selected in step S14, the imaging steps associated with the multiple types of examination reports may overlap. For example, as shown in FIG. 6, when "polarization map", "macular map", and "glaucoma map" are selected, the imaging step "Cube" overlaps in all three examination reports. Therefore, when the three examination reports "polarization map", "macular map", and "glaucoma map" are selected in step S14, the calculation unit 202 determines that the imaging step "Cube" overlaps.

[0046] If there are overlapping imaging steps (YES in step S18), the calculation unit 202 deletes the overlapping imaging steps (S20). For example, if three examination reports, "polarization map", "macular map", and "glaucoma map", are selected in step S14, the imaging steps identified in step S16 are "Cube" associated with "polarization map", "Cube" associated with "macular map", and "Cube" and "Cube Disk" associated with "glaucoma map". Therefore, if all the imaging steps associated with the three selected examination reports are listed, they are "Cube", "Cube", "Cube", and "Cube Disk", and there are three "Cubes". In this case, the calculation unit 202 deletes the overlapping "Cube" (i.e., two of the three "Cubes") from the four listed imaging steps. Then, two imaging steps, "Cube" and "Cube Disk", are left. On the other hand, if there are no overlapping imaging steps (NO in step S18), the calculation unit 202 skips step S20.

[0047] Next, the calculation unit 202 generates a series of control programs (hereinafter also referred to as an imaging program) based on the imaging steps identified in steps S16 to S20 (S22). If it is determined in step S18 that there are overlapping imaging steps, the overlapping imaging steps are deleted in step S20. Therefore, the overlapping imaging steps are deleted from all the imaging steps identified in step S16, and an imaging program is generated for the remaining imaging steps. For example, if three examination reports, "polarization map", "macular map", and "glaucoma map", are selected in step S14, two imaging steps, "Cube" and "Cube Disk", are left in step S20. Therefore, the calculation unit 202 generates an imaging program to execute the two imaging steps, "Cube" and "Cube Disk". On the other hand, if it is determined in step S18 that there are no overlapping imaging steps, the calculation unit 202 generates an imaging program to execute all the imaging steps identified in step S16.

[0048] Next, the calculation unit 202 performs imaging of the subject's eye 500 according to the imaging program generated in step S22 (S24). The process of imaging the subject's eye 500 is performed in the following procedure. First, the examiner operates an operating member such as a joystick (not shown) to align the optical tomographic imaging apparatus with respect to the subject's eye 500. That is, the calculation unit 202 drives a position adjustment mechanism (not shown) in response to the operation of the operating member by the examiner. This adjusts the position of the optical tomographic imaging apparatus in the xy directions (vertical and horizontal directions) and the z direction (direction of forward and backward movement) with respect to the subject's eye 500. Thereafter, the calculation unit 202 performs imaging of the subject's eye 500 according to the imaging program. As described above, the imaging program is composed of one or more imaging steps, and the memory 204 stores detailed setting conditions (imaging conditions) for each imaging step. The calculation unit 202 executes the imaging program according to the detailed setting conditions stored in the memory 204. For example, if three examination reports, "polarization map," "macular map," and "glaucoma map," are selected in step S14, an imaging program consisting of two imaging steps, "Cube" and "Cube Disk," is generated. Therefore, the calculation unit 202 executes the two imaging steps, "Cube" and "Cube Disk," in accordance with this imaging program. The imaging data captured in each imaging step is stored in the memory 204. Hereinafter, the multiple imaging data captured in each imaging step may be collectively referred to as a "imaging data group."

[0049] When the photographing of the subject's eye 500 is completed, the calculation unit 202 generates the examination report selected in step S14 (S26). In step S24, one or more photographing steps are executed, and the photographing data photographed in each photographing step is stored in the memory 204. The calculation unit 202 generates each examination report from the photographing data group using the photographing data photographed in the photographing step corresponding to each examination report.

[0050] For example, when three examination reports, namely, "polarization map", "macular map" and "glaucoma map", are selected in step S14, two imaging steps, "Cube" and "Cube Disk", are executed. As shown in FIG. 6, the imaging step corresponding to the "polarization map" is "Cube". Therefore, the calculation unit 202 generates the "polarization map" using imaging data captured with the "Cube". In addition, since the imaging step corresponding to the "macular map" is "Cube", the calculation unit 202 also generates the "macular map" using imaging data captured with the "Cube". Both the "polarization map" and the "macular map" can be generated using imaging data captured with the "Cube", and the "polarization map" and the "macular map" can be generated by changing the analysis procedure, the analysis target part of the subject's eye 500, and the like. In addition, since the imaging data corresponding to the "glaucoma map" is "Cube" and "Cube Disk", the imaging data captured with the "Cube" is also used to generate the "glaucoma map". In this way, when multiple examination reports that can be generated with the same imaging step are selected, the same imaging step (in this embodiment, "Cube") can be executed once and used to generate any of the different examination reports. In this embodiment, when imaging steps overlap, the imaging program is generated by deleting the overlapping imaging steps. This reduces the time required for imaging and the burden on the subject.

[0051] Even if there are no overlapping imaging steps, the type of examination report is selected first, and an imaging program is generated that combines imaging steps so that all selected examination reports can be generated. For example, in the example shown in Fig. 6, when two examination reports, "polarization map" and "nipple shape analysis", are selected, "Cube" corresponding to "polarization map" and "Cube Disk" and "Circle Disk" corresponding to "nipple shape analysis" are specified as imaging steps. Therefore, an imaging program consisting of three steps, "Cube", "Cube Disk" and "Circle Disk", is generated, and when this imaging program is executed, the three imaging steps, "Cube", "Cube Disk" and "Circle Disk", are executed in a series of operations. In this way, imaging for generating multiple examination reports is performed at once, so there is no need to separately instruct and execute imaging for generating each examination report, and the time required for imaging for generating all examination reports can be shortened.

[0052] Finally, the calculation unit 202 displays the examination report generated in step S26 on the monitor 120 (S28). When multiple examination reports are selected, all the examination reports may be displayed on one screen, or each examination report may be displayed in a switchable manner so that only one examination report is displayed.

[0053] FIG. 7 is an example of a display image 600 of a polarization map. The polarization map is generated by analyzing the photographing data photographed in the photographing step set in "Cube". As shown in FIG. 7, the polarization map includes a fundus image 602 of the subject's eye 500, a tomographic image 604, an en-face image 606 showing thickness, an en-face image 608 showing entropy, and an en-face image 610 showing birefringence. The tomographic image 604 shows a cross section at the position indicated by the arrow in the fundus image 602. The en-face images 606, 608, and 610 show the range surrounded by a square in the fundus image 602. The polarization map also includes an en-face image 612 showing thickness of an eye in a normal state (hereinafter also simply referred to as "normal eye") different from the subject's eye 500, an en-face image 614 showing entropy, and an en-face image 616 showing birefringence. Since the polarization map includes the en-face images 612, 614, and 616 of the normal eye, the condition of the test eye 500 can be easily understood by comparing the test eye 500 with the normal eye. In this way, since the polarization map includes images related to various polarizations that can be generated from the imaging data captured by the "Cube", the condition of the test eye 500 can be easily understood.

[0054] FIG. 8 is an example of a display image 700 of a macular map. The macular map is generated by analyzing the photographed data photographed in the photographing step set in "Cube". As shown in FIG. 8, the macular map includes a fundus image 702 of the subject eye 500, a tomographic image 704, an en-face image 706 showing the thickness, a tomographic image 708 showing the entropy, maps 710 and 712 showing the average thickness and quantitative value evaluation of the volume, and maps 714 and 716 showing the surface. The tomographic images 704 and 708 show a cross section at the position shown by the arrow in the fundus image 702. The en-face image 706 shows the range surrounded by a square in the fundus image 702. The maps 710 and 712 showing the quantitative value evaluation correspond to the circle and line shown in the en-face image 706 showing the thickness. The macular map also includes an en-face image 718 showing the thickness of a normal eye. In this way, the macular map includes various images of the macula that can be generated from the imaging data captured by the "Cube," making it easier to understand the state of the macula of the subject's eye 500.

[0055] FIG. 9 is an example of a display image 800 of a glaucoma map. The macular map is generated by analyzing two pieces of photographed data captured in the photographing steps set in "Cube" and "Cube Disk". As shown in FIG. 9, the glaucoma map includes a fundus image 802 of the subject's eye 500, a tomographic image 804, and en-face images 806 and 808 showing thickness. The tomographic image 804 shows a cross section at the position indicated by the arrow in the fundus image 802. The en-face image 806 shows the area surrounded by a square on the right side of the fundus image 802 (the area including the macula), and the en-face image 808 shows the area surrounded by a square on the left side of the fundus image 802 (the area including the optic disc). The tomographic image 804 and the en-face image 806 are generated from photographed data captured in "Cube", and the en-face image 808 is generated from photographed data captured in "Cube Disk". The glaucoma map also includes a plurality of en-face images 810 showing the thickness of a normal eye. The plurality of en-face images 810 are en-face images in various depth ranges of a normal eye, and are generated from imaging data obtained by imaging a normal eye with the "Cube" and the "Cube Disk". In this way, the glaucoma map includes various images related to glaucoma that can be generated from imaging data obtained by imaging the normal eye with the "Cube" and the "Cube Disk", making it easier to understand the pathological condition related to glaucoma of the test eye 500.

[0056] Example 2 In the above-mentioned first embodiment, the subject's eye 500 is photographed so that a desired examination report can be selected from a plurality of types of examination reports and the selected examination report can be generated, but the present invention is not limited to such a configuration. For example, the subject's eye 500 may be photographed according to an imaging program capable of generating all of the plurality of selectable examination reports. This embodiment differs from the first embodiment in that the memory 204 stores one imaging program including imaging steps capable of generating all of the plurality of types of examination reports, and the other configurations are the same as those of the first embodiment. Therefore, the description of the same configuration as the first embodiment will be omitted.

[0057] Fig. 10 is a flow chart showing an example of a process for generating an examination report of the subject's eye 500 in this embodiment. As shown in Fig. 10, first, the calculation unit 202 executes imaging of the subject's eye 500 according to an imaging program stored in the memory 204 (S32). In the above-mentioned embodiment 1, an imaging program is generated according to a selected examination report, and the subject's eye 500 is imaged according to the generated imaging program, but in this embodiment, the subject's eye 500 is imaged according to a preset imaging program.

[0058] For example, in this embodiment, it is assumed that three examination reports, "polarization map", "macular map" and "glaucoma map", can be generated. As described above, the imaging step for generating the "polarization map" is "Cube", the imaging step for generating the "macular map" is "Cube", and the imaging steps for generating the "glaucoma map" are "Cube" and "Cube Disk" (see FIG. 6). Therefore, the imaging program capable of generating the three examination reports, "polarization map", "macular map" and "glaucoma map", is set to include "Cube" and "Cube Disk". Therefore, the calculation unit 202 executes two imaging steps, "Cube" and "Cube Disk", according to the imaging program. The imaging data captured in each imaging step is stored in the memory 204.

[0059] 10, the calculation unit 202 causes the monitor 120 to display the types of examination reports that can be generated (S34). For example, in the above example, the examination reports that can be generated are three: "polarization map", "macular map", and "glaucoma map". In this case, the calculation unit 202 causes the monitor 120 to display the three: "polarization map", "macular map", and "glaucoma map".

[0060] Next, it is determined whether or not a type of examination report has been selected (S36). Note that the process of step S36 is similar to the process of step S14 in the first embodiment, and therefore a detailed description thereof will be omitted.

[0061] When the type of examination report is selected, the calculation unit 202 generates the examination report selected in step S36 (S38). At this time, from the group of shooting data stored in the memory 204, the shooting data captured in the shooting step corresponding to the type of the selected examination report is used. For example, when the "polarization map" and the "macular map" are selected in step S36, the calculation unit 202 generates the "polarization map" and the "macular map", respectively, using the shooting data captured by the "Cube". Thereafter, the calculation unit 202 displays the examination report generated in step S38 on the monitor 120 (S40).

[0062] In the above example, even though two imaging steps, "Cube" and "Cube Disk", are executed according to the preset imaging program, the examiner selects "polarized map" and "macular map", so only the imaging data captured by "Cube" is used, and the imaging data captured by "Cube Disk" is not used. However, when the examiner requests a "glaucoma map" after imaging, the "glaucoma map" can be generated using the imaging data captured by "Cube Disk" among the data already captured. Therefore, although the imaging time may be long, an examination report different from the examination report desired at the time of imaging can be generated without re-imaging. As a result of evaluating the examination report desired at the time of imaging, another examination report may be required. In such a case, another examination report can be generated without re-imaging, reducing the burden on the examinee and the examiner.

[0063] In the above embodiment, a polarization-sensitive optical tomographic imaging device is used, but the present invention is not limited to this configuration. The type of optical coherence tomography is not particularly limited, and may be, for example, an optical tomographic imaging device that is not polarization-sensitive. In the above embodiment 2, the type of the examination report to be output after imaging is selected, but imaging may be started after the type of the examination report is selected, as in embodiment 1.

[0064] Although specific examples of the technology disclosed in this specification have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. Furthermore, the technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology exemplified in this specification or drawings achieves multiple objectives simultaneously, and achieving one of the objectives itself has technical utility. [Explanation of symbols]

[0065] 10: Measuring part 11:Light source 43: Reference mirror 60, 70: interference light generating unit 80, 90: interference light detector 81, 82, 91, 92: Balanced photodetector 83, 93: Signal processor 84, 85, 94, 95: Signal processing section 100: Sampling trigger / clock generator 120: Monitor 140: Sampling trigger generator 160: Sampling clock generator 200: Arithmetic device 202: Arithmetic section 204: Memory 500: Test eye S1, S2: Measurement optical path R1, R2: Reference optical path

Claims

1. an imaging unit that captures a tomographic image of the subject's eye; a storage means for storing a specific control program for causing the imaging unit to perform imaging capable of generating a plurality of types of examination reports; a control unit that causes the photographing unit to perform the photographing in accordance with the specific control program stored in the storage means; a photographing instruction means for instructing the photographing unit to photograph; a report instruction means for instructing at least one of a plurality of types of the examination report that can be generated by the imaging; a generating unit that generates the examination report instructed by the report instructing means based on specific shooting data included in a shooting data group obtained by the control unit causing the shooting unit to perform shooting according to the specific control program, the specific control program stored in the storage means includes a plurality of imaging steps capable of generating the plurality of types of examination reports, the control unit, when the imaging instruction means instructs the imaging unit to perform the imaging capable of generating the plurality of types of examination reports in accordance with the specific control program, the plurality of types of inspection reports include a first inspection report showing a first inspection result and a second inspection report showing a second inspection result; The first imaging step corresponding to the first examination report includes a specific imaging step, a second imaging step corresponding to the second examination report includes the specific imaging step, the specific control program includes a photographing step included in one of the first photographing step and the second photographing step, and the specific photographing step included in both the first photographing step and the second photographing step, In the specific control program, the specific photographing step included in one of the first photographing step and the second photographing step is omitted, The generation unit generates the inspection report instructed by the report instruction means based on the shooting data included in the shooting data group obtained when the control unit causes the shooting unit to perform shooting in accordance with the specific control program.

2. The optical tomographic imaging device described in claim 1, wherein the control unit generates, for each type of inspection report, an inspection report of that type based on the shooting data captured by executing the shooting step corresponding to that type of inspection report from the group of shooting data obtained by executing the specific control program.

3. An optical tomographic imaging device as described in claim 1 or 2, further comprising an output unit that outputs multiple types of inspection reports generated from the imaging data captured in accordance with the specific control program.

Images