Large Field-of-View Coherence Tomography Device

Abstract

The present invention provides a large-field-of-view coherent tomography imaging device, comprising: at least two sub-units, a receiving optical fiber, and an imaging device. Each sub-unit has a compound eye structure, and a plurality of lens groups with different fields of view and laser emitters are uniformly integrated on a hemispherical housing; all the sub-units are arranged on the same flat structure; the receiving optical fiber is connected to the lens groups, and the field-of-view information of the lens groups with the same field of view on each sub-unit is coupled through F-number matching; the imaging device is connected to the end of the receiving optical fiber, and the field-of-view information of the lens groups with different fields of view is stitched together into large-field-of-view coherent tomography imaging by using a smoothing window. The present invention avoids the division and processing of the reference arm and the detection arm through a self-reference method, and realizes large-field-of-view coherent tomography imaging through the stitching processing of multiple fields of view, avoiding the problem that only the central position is clearly imaged and effective in the traditional interference method; at the same time, the field-of-view angles of each lens group are fixed, and the parallax generated by different fields of view can be corrected through the lens groups.

Description

Technical Field

[0001] The present invention relates to the technical field of optical coherence tomography, and specifically provides a large field of view coherence tomography imaging device. Background Art

[0002] Optical Coherence Tomography (OCT for short) is a new imaging technology based on optical coherence characteristics. It analyzes the interference signal between the backscattered or reflected light of a biological tissue sample and a reference light to perform tomography imaging on the internal structure of the biological tissue sample, obtaining the tissue characteristics of an optical tomogram to determine the target to be identified for diagnosis. Compared with conventional imaging means, OCT technology has unique advantages. Its imaging effect is close to pathology, and it also has the advantages of non-invasive, non-radiative, real-time in-vivo observation, high resolution, in-tissue depth imaging, 3D image data, etc. Currently, OCT technology has become an important tool for detecting retinal diseases.

[0003] Existing optical coherence tomography imaging devices require multiple pairs of reference arms and detection arms, and the structure is very complex. However, for the actual diffraction imaging field of view, only the central part has good effects, while the edge effects are poor, resulting in a still small actual imaging field of view. When performing large field of view scanning, problems such as insufficient imaging field of view and blurred imaging edges will occur, bringing difficulties in aligning the imaging field of view. Moreover, the reference arm and the detection arm of existing optical coherence tomography imaging devices are independent of each other, with different imaging angles, and parallax will inevitably occur during coupling. Therefore, subsequent processing must be carried out to eliminate the parallax, and this process is rather troublesome and has low accuracy. Summary of the Invention

[0004] To solve the above problems, the present invention provides a device with a simple structure that can achieve large field of view coherence tomography through structural optimization.

[0005] The large field of view coherence tomography imaging device provided by the present invention includes:

[0006] At least two sub-units, each sub-unit is a compound eye structure, and a plurality of lens groups with different fields of view and at least one laser emitter are uniformly integrated on a hemispherical shell. There is an overlap between different fields of view. The lens groups are used to correct the parallax generated by different fields of view, and the laser emitter is used for laser illumination; all sub-units are arranged on the same flat plate structure;

[0007] A receiving optical fiber, which is connected to the lens group through F-number matching, is used to receive field of view information and couple the field of view information of the lens groups with the same field of view on each sub-unit; the lens groups with the same field of view can perform self-reference through adjacent fields of view or opposite fields of view;

[0008] An imaging device, which is connected to the end of a receiving optical fiber, is used to process the field-of-view information of the same field of view, and uses a smoothing window to splice the field-of-view information of lens groups with different fields of view into a large field-of-view coherent tomography.

[0009] Preferably, the imaging device uses a spectral imager.

[0010] Preferably, the field-of-view information of different wavelengths obtained by the spectral imager corresponds to the imaging information of different depths.

[0011] Preferably, the receiving optical fibers are connected in a form of step-by-step full connection.

[0012] Preferably, the laser emitter is arranged at the edge of the hemispherical shell.

[0013] Preferably, the overlapping area between different fields of view is a common field of view, and the phase difference and data of different fields of view are corrected by the unique certainty of the information within the common field of view.

[0014] Preferably, the flat plate structure uses a glass substrate.

[0015] Preferably, each lens group is connected to the hemispherical shell through a columnar lens barrel with openings at both ends, and the columnar lens barrel can be rotated at different angles to change its corresponding field of view and fill the gap between adjacent fields of view.

[0016] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0017] The present invention avoids the division and processing of the reference arm and the detection arm through a self-reference method, and then realizes large field-of-view coherent tomography through the splicing process of multiple fields of view, avoiding the problem that only the central position is clearly imaged effectively in the traditional interference method; at the same time, the field-of-view angles of each lens group are fixed, and the parallax generated by different fields of view can be corrected through the lens group, without the need for parallax correction through data processing in the traditional coherent tomography system.

[0018] The structure of the present invention is simple, easy to operate, and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic structural diagram of a large field-of-view coherent tomography device provided according to an embodiment of the present invention.

[0020] The reference numerals therein include:

[0021] Sub-unit 1, lens group 11, laser emitter 12, hemispherical shell 13, flat plate structure 2, receiving optical fiber 3, imaging device 4. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] In the following, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same modules are denoted by the same reference numerals. In the case of the same reference numerals, their names and functions are also the same. Therefore, their detailed descriptions will not be repeated.

[0023] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation to the present invention.

[0024] Figure 1 The simplified structure of a large field-of-view coherent tomography apparatus according to an embodiment of the present invention is shown.

[0025] As Figure 1 shown, the large field-of-view coherent tomography apparatus provided by the embodiment of the present invention includes at least two sub-units 1, a flat plate structure 2, a receiving optical fiber 3, and an imaging device 4, wherein:

[0026] The sub-unit 1 includes: a lens group 11, a laser emitter 12, and a hemispherical housing 13. All the sub-units 1 are arranged on the same flat plate structure 2, and the flat plate structure 2 can adopt a glass substrate. Each sub-unit 1 has a compound eye structure. A plurality of lens groups 11 and a laser emitter 12 are uniformly integrated on a hemispherical housing. Different lens groups 11 are set at different installation angles. Different lens groups 11 correspond to different fields of view, and there is an overlapping area between different fields of view, ensuring that there is a certain overlapping area between different imaging fields of view during the detection process. This overlapping area is the common field of view of the plurality of lens groups 11. The phase difference correction and data correction of different imaging fields of view can be performed by using the unique certainty of the overlapping information in the common field of view, ensuring a better imaging result on the entire field of view finally. In addition, each lens group 11 is connected to the hemispherical housing 13 through a columnar lens barrel with openings at both ends, and the columnar lens barrel can be rotated at different angles to change its corresponding field of view, fill the gap between adjacent fields of view, and avoid the appearance of missing fields of view during field-of-view stitching.

[0027] The lens group 11 is assembled by combining different lenses and is set separately according to its installation angle, and the distortion and chromatic dispersion errors generated by different fields of view are corrected through the lens structure. The laser emitter 12 is arranged at the edge position of the hemispherical housing 13 for laser illumination. The lens group 11 receives the reflected laser to form a sub-aperture, which can improve the signal-to-noise ratio.

[0028] The output ends of the lens groups 11 are all connected to the receiving optical fiber 3 through F-number matching. The receiving optical fiber 3 is used to receive the field-of-view information obtained by the lens groups 11, and couple the field-of-view information obtained by the lens groups 11 with the same installation angle of each subunit 1, that is, couple the field-of-view information obtained by the lens groups 11 with the same field of view. When the number of subunits 1 is two, it is equivalent to the reference arm and the detection arm of the existing optical coherence tomography device. However, different from the device, the present invention does not need to divide the reference arm and the detection arm and perform different treatments on them. In the embodiments of the present invention, the lens groups 11 with the same field of view can perform self-reference through adjacent fields of view or opposite fields of view.

[0029] It should be noted that: only the fiber coupling of two lens groups with the same field of view is shown as an example in Figure 1 . In the actual device, all the lens groups 11 with the same field of view are coupled together by optical fibers, and an imaging device 4 is connected after the coupling.

[0030] In this embodiment, the imaging device 4 uses a spectral imager. The spectral imager is connected to the end of the receiving optical fiber 3 and is used to process the field-of-view information of the same field of view. The field-of-view information of different wavelengths obtained by the same spectral imager corresponds to imaging information of different depths, so that optical coherence tomography can be realized. The interference patterns obtained by each spectral imager respectively construct images in each field of view to obtain an effect of local clarity and blurred edges of the object. Through the overlap and sharing between each field of view, the field-of-view information of the lens groups 11 in different fields of view is spliced using a smoothing window. Processing the overlapping information using a smoothing window belongs to the prior art and will not be elaborated in detail here. And the phase difference correction and data correction of different imaging fields of view can be performed using the unique certainty of the overlapping information in the shared field of view to ensure a better imaging result is finally obtained on the entire field of view. Compared with the field of view obtained by the traditional optical coherence tomography system, the field of view of this entire field of view is larger and the imaging effect is clearer. And the structure of this device is simple, easy to operate, and has good application prospects.

[0031] Based on the large-field-of-view optical coherence tomography device provided by the present invention, its optimization design can also be carried out. To meet the requirements of integration and miniaturization, a meta-macro combined structure can be formed on the flat structure 2 through micro-nano direct writing technology. The meta-macro combined structure replaces the lens group 11, the laser emitter 12, and the hemispherical shell 13 in the subunit 1, and thus the integration of the subunit 1 can be realized. This design can achieve the miniaturization of the subunit 1.

[0032] In addition, an interference module can be used to replace the receiving optical fiber 3 and the imaging device 4, and the interference module is directly written into the flat structure 2, which can realize the overall thin-plate and integrated interference. However, the detection wavelength of this optimized design will be limited, and it is suitable for producing small and simple large-field-of-view optical coherence tomography devices.

[0033] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0034] The above specific embodiments of the present invention do not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and deformations made according to the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A large field of view coherence tomography device, characterized in that Further comprising: At least two sub-units, each of which is a compound eye structure, with a plurality of lens groups with different fields of view and at least one laser emitter uniformly integrated on the hemispherical shell. There is an overlap between different fields of view. The lens groups are used to correct the parallax generated by different fields of view, and the laser emitter is used for laser illumination; all the sub-units are arranged on the same flat structure; A receiving optical fiber, which is connected to the lens group through F-number matching, is used to receive field-of-view information and couple the field-of-view information of the lens groups with the same field of view on each sub-unit; The lens groups with the same field of view can be self-referenced through adjacent fields of view or opposite fields of view; An imaging device, which is connected to the end of the receiving optical fiber, is used to process the field-of-view information of the same field of view and splice the field-of-view information of the lens groups with different fields of view into a large-field-of-view coherent tomography imaging by using a smoothing window.

2. The large field of view optical coherence tomography device according to claim 1, characterized in that, The imaging device uses a spectral imager.

3. The large field of view optical coherence tomography apparatus according to claim 2, wherein The field-of-view information of different wavelengths obtained by the spectral imager corresponds to imaging information of different depths.

4. The large field of view coherent tomography device according to claim 1, characterized in that, The receiving optical fiber is connected in a step-by-step fully connected combination form.

5. The large field of view coherent tomography apparatus according to claim 1, wherein The laser emitter is arranged at the edge of the hemispherical shell.

6. The large field of view optical coherence tomography device according to claim 1, characterized in that, The overlapping area between different fields of view is a common field of view, and the phase difference and data of different fields of view are corrected by the unique certainty of the information in the common field of view.

7. The large field of view coherent tomography apparatus according to claim 1, wherein The flat structure uses a glass substrate.

8. The large field of view optical coherence tomography device according to claim 1, wherein Each lens group is connected to the hemispherical shell through a columnar lens barrel with openings at both ends, and the columnar lens barrel can be rotated at different angles to change its corresponding field of view and fill the gap between adjacent fields of view.

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