CN-122018129-A - Anterior ocular segment transmission interference microscopic imaging device, method and system

CN122018129ACN 122018129 ACN122018129 ACN 122018129ACN-122018129-A

Abstract

The invention provides a device, a method and a system for transmission interference microscopic imaging of anterior ocular segment, and relates to the technical field of medical optical imaging and ophthalmic diagnosis. The single-frame imaging visual field of the invention is not less than 2mm multiplied by 1mm and is larger than that of a common clinical confocal microscope and a cornea endothelial mirror, the statistical reliability and the lesion detection rate can be improved, the cornea nerves, epithelial cells and lens microstructure can be displayed in a high contrast mode through a transmission interference mechanism, the single-frame imaging visual field is especially suitable for low-scattering transparent tissues, a common-path optical structure is adopted, a reference arm or a high-speed scanning unit is not needed, the system is small in size, low in cost and good in stability, an ocular surface is not needed to be contacted or contrast agent is not needed to be introduced in the inspection process, discomfort and risks possibly caused by the traditional contact or invasive inspection are avoided, and the single-frame imaging visual field can be used for cornea nerve assessment, endothelial disease screening, lens microstructure observation and preoperative/postoperative follow-up.

Inventors

YANG JIANWEN
Ye Xiadi
HUANG JIANGJIE
HE YI

Assignees

中国科学院苏州生物医学工程技术研究所

Dates

Publication Date: 20260512
Application Date: 20260226

Claims (14)

1. A anterior ocular segment transmission interference microscopy imaging device, comprising: The illumination unit is used for emitting an illumination beam and projecting the illumination beam to the rear tissue of human eyes; The posterior tissue is configured to scatter upon receiving the illumination beam to form a secondary light source for transilluminating anterior ocular segment tissue; an imaging unit for collecting and detecting light signals transmitted through the anterior ocular segment tissue; wherein the optical signal transmitted through the anterior ocular segment tissue comprises a transmitted zero order light generated by the secondary light source and a diffracted light generated by the microstructure of the anterior ocular segment tissue, the transmitted zero order light interfering with the diffracted light, the imaging unit being configured to receive and form an image reflecting an interference intensity distribution.
2. The device of claim 1, wherein the illumination unit comprises a light source, a collimating element and a projection objective, and the light beam emitted from the light source is collimated by the collimating element, focused by the projection objective and incident on human eyes, and finally imaged on the rear tissue.
3. A anterior ocular segment transmission interference microscopy imaging device as in claim 2, wherein the illumination unit further comprises a spot modulation component for modulating a spot size of the illumination beam formed on the posterior tissue to change an effective numerical aperture and spatial coherence of the secondary light source.
4. A anterior ocular segment transmission interference microscopy imaging device as in claim 1, further comprising a polarization control unit; the polarization control unit comprises a polarizer and a polarization beam splitting element; The polarizer is used for adjusting the illumination light beam into linearly polarized light; The polarization splitting element is positioned in the illumination light path and the imaging light path, and is used for reflecting the linearly polarized light from the illumination unit to illuminate human eyes and transmitting the signal light from the human eyes, the polarization state of which is changed, to enter the imaging unit.
5.A anterior ocular segment transmission interference microscopic imaging device as in claim 4, wherein the polarization control unit is configured such that the polarization state of the illumination beam is in a cross-polarized relationship with the polarization state of the probe light entering the imaging unit to suppress specular reflected light from the anterior ocular segment tissue surface.
6. A anterior ocular segment transmission interference microscopic imaging device as in claim 1, wherein the imaging unit comprises a microscope objective, an imaging lens, and a two-dimensional area array detector; The micro objective lens is used for collecting optical signals from human eyes; the imaging lens and the microscope objective form a 4f relay system, and the image surface of the microscope objective is relayed to the target surface of the two-dimensional area array detector; the two-dimensional area array detector is used for recording the interference intensity distribution and forming a single-frame large-view-field anterior ocular segment image.
7. The transmission interference microscopy imaging device of claim 1, wherein the posterior tissue is a sclera or retina, and wherein the anterior ocular segment tissue comprises at least one of a cornea, an anterior chamber angle, or a anterior lens.
8. A anterior ocular segment transmission interference microscopy imaging device as in any of claims 1 to 7, wherein the illumination beam is near infrared light.
9. A method of transmission interference microscopy of the anterior ocular segment based on the device of any one of claims 1 to 8, comprising the steps of: s1, projecting an illumination beam to rear tissues of human eyes to be detected, forming a secondary light source by utilizing scattering of the rear tissues, and carrying out transmission illumination on anterior ocular segment tissues; s2, collecting an optical signal transmitted through the anterior ocular segment tissue, wherein the optical signal comprises transmitted zero-order light from the secondary light source and diffracted light generated by the anterior ocular segment tissue microstructure; s3, enabling the transmitted zero-order light and the diffracted light to interfere, and detecting intensity distribution formed by interference through an imaging unit, so that a single-frame large-view-field and cell-order-resolution transmission interference image of the anterior ocular segment tissue is obtained.
10. A method of anterior ocular segment transmission interference microscopy as claimed in claim 9, wherein in step S1 the spot size of the illumination beam on the posterior tissue is controlled by adjusting the illumination path to adjust the depth of field and interference contrast of the image.
11. A method of transmission interference microscopy of the anterior ocular segment as in claim 9, further comprising the step of polarization control using a cross-polarization configuration to suppress specularly reflected light from the anterior surface of the cornea and to allow unpolarized transmitted signal light scattered by said posterior tissue to enter the imaging unit.
12. A method of transmission interference microscopy of the anterior segment of the eye as defined in claim 9, wherein the imaging unit employs a non-scanning wide-field imaging mode, and the field of view of the single frame image is greater than or equal to 1mm x 1mm.
13. A anterior ocular segment transmission interference microscopy imaging system, comprising: a anterior ocular segment transmission interference microscopy imaging device as in any of claims 1 to 8; and the processing unit is in communication connection with the imaging unit and is used for receiving the image data acquired by the imaging unit and carrying out image enhancement or analysis processing.
14. The anterior ocular segment transmission interference microscopy imaging system of claim 13, wherein the processing unit is configured to perform at least one of background noise suppression, contrast enhancement, cell boundary recognition, neuromorphic extraction, or quantitative parameter calculation.

Description

Anterior ocular segment transmission interference microscopic imaging device, method and system Technical Field The invention relates to the technical field of medical optical imaging and ophthalmic diagnosis, in particular to a device, a method and a system for transmission interference microscopy imaging of anterior ocular segment. Background Currently, clinical imaging of anterior ocular segment microstructure relies mainly on several types of techniques: (1) Corneal endothelioscopy (Specular Microscopy) based on the principle of specular reflection, which forms an image by detecting reflected light from the corneal endothelium-aqueous humor interface, is widely used for endothelial cell density assessment. The equipment has mature structure and simple and convenient operation, but has the technical defects that the imaging is limited to a single layer of cornea endothelium, the cornea epithelium, stroma or nerve structure cannot be observed, the single-frame visual field is smaller, usually not more than 0.25mm multiplied by 0.5mm, the space sampling is limited, and the equipment is sensitive to corneal turbidity and endothelial lesions (such as Fuchs endothelial malnutrition) and is easy to saturate or distort the image. (2) The confocal microscope (In vivo Confocal Microscopy, IVCM) realizes axial optical section with Jiao Kongjing by point scanning, and can obtain cell-level resolution, and observe the cells and nerve structures of each layer of cornea. However, the defects of the system include extremely small single-frame visual field (usually about 0.4mm multiplied by 0.4 mm), difficulty in reflecting the whole structure of tissues, high requirements on comfort of patients and experience of operators due to the need of contacting or approaching the ocular surface, complex system structure and high cost, and difficulty in popularization in a base layer or a resource-limited area. (3) High resolution Optical Coherence Tomography (OCT) is that full field OCT, line field OCT and other technologies which appear in recent years can realize non-contact cell-level tomography, but the system usually depends on a high-speed detector, a complex scanning structure or an interference subsystem, and has the following problems of high system complexity, high cost, large volume and unfavorable clinical routine deployment, and a contrast mechanism for transparent tissues is mainly reflection/backscattering, and has limited contrast for certain low scattering structures (such as nerves). (4) Transmission or reverse-transmission illumination imaging (Retro-illumination) has long been used in clinical slit lamps to observe lens haze or corneal defects, but this approach only provides macroscopic low resolution information, and cell-level imaging is difficult to achieve, mainly due to insufficient spatial coherence of illumination and weak interference contrast. In summary, the prior art is difficult to combine in terms of large field of view, cell-level resolution, high contrast of transparent tissue and system simplification, and still has obvious technical blank. Disclosure of Invention To achieve the above and other advantages and in accordance with the purpose of the present invention, a first object of the present invention is to provide a anterior ocular segment transmission interference microscopy imaging device comprising: The illumination unit is used for emitting an illumination beam and projecting the illumination beam to the rear tissue of human eyes; The posterior tissue is configured to scatter upon receiving the illumination beam to form a secondary light source for transilluminating anterior ocular segment tissue; an imaging unit for collecting and detecting light signals transmitted through the anterior ocular segment tissue; wherein the optical signal transmitted through the anterior ocular segment tissue comprises a transmitted zero order light generated by the secondary light source and a diffracted light generated by the microstructure of the anterior ocular segment tissue, the transmitted zero order light interfering with the diffracted light, the imaging unit being configured to receive and form an image reflecting an interference intensity distribution. The illumination unit comprises a light source, a collimation element and a projection objective, wherein the light beam emitted by the light source is focused by the projection objective and enters human eyes after being collimated by the collimation element, and finally is imaged on the rear tissue. Further, the illumination unit also includes a spot modulation component for modulating a spot size of the illumination beam formed on the posterior tissue to change an effective numerical aperture and spatial coherence of the secondary light source. Further, the device also comprises a polarization control unit; the polarization control unit comprises a polarizer and a polarization beam splitting element; The polarizer is used for adjusting the i