CN110215183B - Vision fixation optical device, ophthalmologic measurement system and imaging method - Google Patents

Abstract

The application discloses a fixation optical device, an ophthalmologic measurement system and an imaging method. The vision fixation optical device comprises a plurality of groups of vision fixation light sources arranged along a light path according to a set interval; the fixation light source comprises a light emitting device, a first optical device and a fixation pattern arranged on the first optical device; the light emitting device is used for irradiating the vision fixation pattern along the lateral direction of the first optical device; and the fixation patterns of the multiple groups of fixation light sources are arranged along the light path. The ophthalmic measurement system includes the fixation optics. The imaging method comprises the steps of receiving front-back section interference spectrum signals; dividing the front and rear section interference spectrum into a long waveband and a short waveband to obtain a long-short waveband interference spectrum and a short-short waveband interference spectrum; and respectively operating the long and short sections of interference spectrum signals to obtain two optical coherence tomography images of the front section and the rear section. The structure of the fixation optical device can be simplified, the number of adjusting parts can be reduced, and therefore cost is reduced.

Description

Vision fixation optical device, ophthalmologic measurement system and imaging method

Technical Field

The present application relates to the field of optical devices and optical coherence tomography, and more particularly to a vision fixation optical device, an ophthalmic measurement system, and an imaging method.

Background

In ophthalmology, the eye of a subject is allowed to fixate, specifically, the eye of the subject fixates a fixation pattern in a fixation optical device, for example: the vision fixation training is performed before the operation, or the vision fixation maintaining capability is checked. Because different testees 'eyes have different dioptres, in order to realize better effect, need focus to the diopter of different testees' eyes, just also need adopt the focusing motor. In order to perform focusing using a focusing motor, an associated circuit and mechanism are required.

Disclosure of Invention

The application provides a fixation optical device, an ophthalmologic measurement system, and an imaging method, which can naturally fix the vision of the eyes of a person to be measured, thereby avoiding the use of a focusing motor.

In a first aspect, an embodiment of the present application provides a vision fixation optical device, including multiple groups of vision fixation light sources arranged along a light path at set intervals;

the fixation light source comprises a light emitting device, a first optical device and a fixation pattern arranged on the first optical device;

the light emitting device is used for irradiating the fixation pattern along the lateral direction of the first optical device so that the fixation pattern becomes a secondary light source;

the fixation patterns of the multiple groups of fixation light sources are arranged along the optical path, and at least one of the multiple fixation patterns can be observed along the optical path at least partially.

In one possible implementation, the sizes of the vision fixation patterns are different; or the sizes of the plurality of fixation patterns are the same, and the projections of the plurality of fixation patterns on a projection plane perpendicular to the optical path are mutually staggered by at least one part.

In one possible implementation, the fixation pattern may scatter light.

In a possible implementation manner, the material of the first optical device is glass, and the fixation pattern is a frosted pattern disposed on the first optical device.

In one possible implementation, the first optical device is a flat glass; the number of the vision fixation light sources is more than three groups.

In a second aspect, an ophthalmic measurement system is provided in an embodiment of the present application, including the above fixation optical device.

In a possible implementation mode, the system further comprises an optical coherence tomography device and an iris camera device; the optical coherence tomography device comprises a sample arm, wherein the sample arm comprises an ocular objective lens and a front dichroic mirror which are sequentially arranged along the light incidence direction;

the iris image pick-up device comprises the eye objective lens, the front dichroic mirror, a relay lens and a third dichroic mirror, wherein the relay lens and the third dichroic mirror are sequentially arranged along the incident direction of light and are positioned behind the front dichroic mirror;

the fixation optical device further comprises the ocular objective, the pre-dichroic mirror, the relay lens and the third beam splitter.

In one possible implementation, the optical coherence tomography apparatus further includes a light source, a fiber coupler, a reference arm, a detection device, and a computer;

the light source can provide light to the sample arm and the reference arm through the fiber coupler;

the detection device is used for detecting the light output by the optical fiber coupler;

the computer is used for processing the data output by the detection device.

In a possible implementation manner, the reference arm comprises a reference arm light path lens, a reference arm spectroscope, an anterior segment reference arm reflector and a posterior segment reference arm reflector, wherein the reference arm light path lens, the reference arm spectroscope, the anterior segment reference arm reflector and the posterior segment reference arm reflector are sequentially arranged along the incident direction of light;

the reference arm beamsplitter is transmissive to light of a first wavelength and reflective to light of a second wavelength, the first wavelength being a different wavelength than the second wavelength; the anterior ocular segment reference arm mirror may reflect light of the first wavelength; the posterior eye reference arm mirror may reflect the light of the second wavelength;

the light with the first wavelength reflected by the anterior ocular segment reference arm reflector of the detected eye can interfere with the light with the first wavelength reflected by the anterior ocular segment reference arm reflector in the optical fiber coupler after passing through the ocular objective lens;

the light with the second wavelength reflected by the eye posterior segment reference arm reflector can interfere with the light with the second wavelength reflected by the eye posterior segment reference arm reflector in the optical fiber coupler after passing through the eye objective lens.

In one possible implementation, the sample arm further comprises a scanning device disposed along the direction of light incidence and located behind the pre-dichroic mirror.

In one possible implementation manner, the reference arm beam splitter is coated with a coating film satisfying: the critical point of total transmission is (λ 0- Δ λ 1), and the critical point of total reflection is (λ 0+ Δ λ 2), whereλ 0 is the ideally set critical wavelength of total reflection and total transmission.

In a third aspect, embodiments of the present application provide an optical coherence tomography method using the ophthalmic measurement system according to the above; the optical coherence tomography method comprises the following steps:

receiving interference spectrum signals of front and rear sections;

dividing the front and rear section interference spectrum into a long waveband and a short waveband to obtain a long-short waveband interference spectrum and a short-short waveband interference spectrum;

and respectively operating the long and short sections of interference spectrum signals to obtain two optical coherence tomography images of the front section and the rear section.

In a fourth aspect, the present application provides a computer-readable storage medium, in which program instructions are stored, and when the program instructions are executed by a processor of a computer, the processor is caused to execute the above method.

Compared with the prior art, the invention has the beneficial effects that:

the multiple groups of fixation light sources of the fixation optical device are arranged along the light path according to a set distance, so that the corresponding multiple groups of fixation patterns are positioned at positions corresponding to different dioptric positions. The sizes of the vision fixation patterns are different and are arranged along the light path. Because the multiple groups of light-emitting devices respectively illuminate the fixed view patterns in the lateral direction, the fixed view patterns become secondary light sources. Thus, the eyes of the testees with different dioptres can naturally see the vision fixation pattern corresponding to the dioptres along the light path, so that the focusing motor is not used for focusing, the structure of the vision fixation optical device can be simplified, the number of adjusting parts can be reduced, and the cost is reduced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments or the background art of the present application, the drawings required to be used in the embodiments or the background art of the present application will be described below.

FIG. 1 is a schematic view of an ophthalmic measurement system according to an embodiment of the present application;

FIG. 2 is another schematic view of an ophthalmic measurement system according to an embodiment of the present application;

FIG. 3 is a schematic structural diagram of an optical coherence tomography apparatus according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of an iris imaging apparatus according to an embodiment of the present application;

FIG. 5 is a schematic structural diagram of a fixation optical device according to an embodiment of the present application;

FIG. 6 is a schematic view of a fixation pattern according to an embodiment of the present disclosure;

FIG. 7 is a schematic structural diagram of a variation of a fixation optical device according to an embodiment of the present application;

FIG. 8 is a waveform of light output by a light source according to an embodiment of the present application;

FIG. 9 is an illustration of interference spectra for an embodiment of the present application;

FIG. 10 is a waveform illustrating the reflection and transmission of an ideal coating for a reference arm beamsplitter according to an embodiment of the present application;

FIG. 11 is a waveform illustrating the reflection and transmission of the actual plating of the reference arm beam splitter in accordance with an embodiment of the present invention;

fig. 12 is a schematic view of a modification of the fixation pattern according to the embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more clear, the present application will be further described in detail with reference to fig. 1 to 11.

The terms "first" and "second," and the like in the description, claims, and drawings of the present application are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

Referring to fig. 1 and 2, the ophthalmologic measurement system of the present embodiment includes an opticalcoherence tomography apparatus 110, aniris imaging apparatus 190, and a fixationoptical apparatus 170. The Optical Coherence Tomography apparatus is also called an OCT (Optical Coherence Tomography) imaging apparatus. In fig. 2, L1 denotes an optical path.

Referring to fig. 3, the opticalcoherence tomography apparatus 110 of the present embodiment includes alight source 1101, afiber coupler 1103, areference arm 112, adetection device 1141, acomputer 1143, and asample arm 130.

Light source 1101 is a weak coherent light source that can provide light tosample arm 130 andreference arm 112 throughfiber coupler 1103. That is, light output from thelight source 1101 passes through thefiber coupler 1103 and is incident on thesample arm 130 and thereference arm 112. Thelight source 1101 outputs light having a wavelength of about near infrared light.

Referring to fig. 3, thereference arm 112 includes a reference armoptical path lens 1121, a referencearm beam splitter 1123, a posterior segmentreference arm mirror 1127, and an anterior segmentreference arm mirror 1125 located at one side of the referencearm beam splitter 1123, which are sequentially disposed along the incident direction of light. Anterior ocular segmentreference arm mirror 1125 may reflect the reflected light of referencearm beam splitter 1123.

In thereference arm 112, the referencearm beam splitter 1123 may be a half mirror or a dichroic mirror. In this embodiment, the referencearm beam splitter 1123 is a dichroic mirror. The referencearm beam splitter 1123 is transmissive to light of a first wavelength and reflective to light of a second wavelength, wherein the first wavelength and the second wavelength are different wavelengths. Specifically, the referencearm beam splitter 1123 transmits light of a longer wavelength and reflects light of a shorter wavelength, or transmits light of a shorter wavelength and reflects light of a longer wavelength. In this embodiment, the referencearm beam splitter 1123 transmits light of a longer wavelength and reflects light of a shorter wavelength; the light of the first wavelength is light of a longer wavelength; the light of the second wavelength is light of a shorter wavelength.

The reference light is transmitted to the referencearm beam splitter 1123 by the reference armoptical path lens 1121, wherein the longer wavelength portion is transmitted to thereference arm reflector 1127 at the posterior segment of the eye through the referencearm beam splitter 1123, and wherein the shorter wavelength portion is transmitted to thereference arm reflector 1125 at the anterior segment of the eye by being reflected by the referencearm beam splitter 1123.

The distance between the reference light transmitted from the reference armoptical path lens 1121 to the anterior eyereference arm reflector 1125 and the distance between the reference light transmitted from the reference armoptical path lens 1121 to the posterior eyereference arm reflector 1127 are preset fixed values.

The longer wavelength reference light is reflected by thereference arm reflector 1127 and returned to thefiber coupler 1103, and the shorter wavelength reference light is reflected by thereference arm reflector 1125 and returned to thefiber coupler 1103.

Referring to fig. 3, thesample arm 130 includes anobjective lens 1311, a frontdichroic mirror 1309, ascanning device 1305, a focusinglens 1303, and apolarization controller 1301, which are sequentially arranged in the direction in which light is incident.

Thesample arm 130 provides the measurement light to the eye E, and the measurement light scattered from the sample, i.e., the eye E, interferes with the reference light reflected from thereference arm 112 through thesample arm 130 in thefiber coupler 1103.

Thescanning device 1305 may employ a one-dimensional scanning mechanism or a two-dimensional scanning mechanism.

When OCT imaging is performed, measurement light emitted from thefocus lens 1303 is reflected by thescanning device 1305. At this time, thescanning device 1305 is controlled by thecomputer 1143, the measuring light beam is reflected by thescanning device 1305, enters thepre-dichroic mirror 1309, is reflected by thepre-dichroic mirror 1309 to theobjective lens 1311, part of the measuring light is reflected by the anterior segment of the eye E to be measured, and part of the measuring light finally passes through the eye E to the fundus oculi and is scattered by the fundus oculi.

The measurement light with a shorter wavelength reflected from the anterior segment of the eye E interferes with the reference light with a shorter wavelength reflected by the anterior segmentreference arm reflector 1125, and the measurement light with a longer wavelength reflected from the posterior segment of the eye E interferes with the reference light with a longer wavelength reflected by the posterior segmentreference arm reflector 1127.

The interference light is detected by the detectingdevice 1141, processed by thecomputer 1143, and finally displayed as an anterior segment and a posterior segment OCT image of the detected sample. The sample is scanned by thescanning device 1305, and tomographic imaging of the OCT is realized.

Referring to fig. 4, theiris imaging device 190 is used for iris preview so as to guide the examiner, i.e., the doctor, to operate the instrument and align the optical path of the probe with the eye of the examinee.

Referring to fig. 4, theiris imaging apparatus 190 includes anillumination light source 1901, anobjective lens 1311, a frontdichroic mirror 1309, arelay lens 1905, a thirddichroic mirror 1907, aniris imaging lens 1909, and animaging apparatus 1911 in this order in the direction in which light is incident. That is, theiris imaging apparatus 190 shares theobjective lens 1311 and the pre-dichroic 1309 with the opticalcoherence tomography apparatus 110. The frontdichroic mirror 1309 transmits light emitted from theillumination light source 1901 in theiris imaging module 190, and reflects signal light emitted from thelight source 1101.

The light emitted from theillumination light source 1901, specifically near-infrared light, is irradiated to the anterior chamber of the eye E, scattered by the anterior chamber tissue, passes through theobjective lens 1311, the pre-dichroic 1309, and therelay lens 1905, then is reflected by the thirddichroic mirror 1907, passes through theiris imaging lens 1909, and finally is captured by theimaging device 1911.

Referring to fig. 5, the fixationoptical device 170 of the present embodiment includes a plurality of sets offixation light sources 1701 arranged along an optical path at set intervals. Thefixation light source 1701 is used for a fixation target (internal fixation target) for fixing the eye E of the subject.

Referring to fig. 5, each set offixation light sources 1701 includes alight emitting device 17011, a firstoptical device 17013, and afixation pattern 17015 disposed on the first optical device. Thelight emitting device 17011 is used for illumination. The firstoptical device 17013 is used to dispose the fixedpattern 17015 in the optical path.

In this embodiment, thefixation light sources 1701 are three groups, andfixation patterns 17015 are provided at different positions in front and rear. In other embodiments, thefixation light sources 1701 may be two, four, five, six, seven, or more than eight groups.

In this embodiment: thelight emitting device 17011 is a fixation lighting LED lamp; the firstoptical device 17013 is a plate glass.

Thefixation pattern 17015 is used for fixation of the eye E to be examined. The threefixation patterns 17015 are of different sizes.

Referring to fig. 5, three firstoptical devices 17013 provided with afixed pattern 17015 are disposed along an optical path, and thus, three fixedpatterns 17015 are also disposed along the optical path. The three light emittingdevices 17011 are located laterally to the three firstoptical devices 17013, respectively, so as to illuminate the fixedpattern 17015 laterally to the firstoptical devices 17013, making the fixed pattern 17015 a secondary light source.

Specifically, thelight emitting device 17011 illuminates the fixedpattern 17015 in the center of the firstoptical device 17013 by illuminating it laterally toward the firstoptical device 17013. At this time, the fixedpattern 17015 emits light as a secondary light source and can be projected to the fundus of the eye E to be examined.

Thefixed pattern 17015 may be formed by frosting a flat glass plate, so that light may be scattered and emitted as a secondary light source after being irradiated with light. In other embodiments, the fixedpattern 17015 is formed by engraving or etching on the light-transmissive optical device.

The spacing between the three groups offixation light sources 1701 is set according to the desired refractive position. Thefirst fixing pattern 17015 and thethird fixing pattern 17015 are respectively located at two sides of thesecond fixing pattern 17015. Thefirst fixation pattern 17015 and thethird fixation pattern 17015 are disposed at locations that just satisfy ± 5D refraction. That is, the eyes of the test subject with ± 5D refraction can see thefirst fixation pattern 17015 or thethird fixation pattern 17015 with less effort. Of course, thefirst fixation pattern 17015 and thethird fixation pattern 17015 may be disposed at other refractive positions.

At least one of the threefixation patterns 17015 may be observed along the optical path at least in part; specifically, the eye E of the subject can observe at least a part of acertain fixation pattern 17015 along the optical path, thereby performing fixation. In the present embodiment, the three fixingpatterns 17015 are all centered on one axis, but the three fixingpatterns 17015 are different in size and shape. The eye to be tested adjusts itself during the testing process, and fixates and views one of the threefixation patterns 17015. Referring to fig. 6, in the present embodiment, among the three fixingpatterns 17015, thefirst fixing pattern 17015 is rectangular, thesecond fixing pattern 17015 is circular, and thethird fixing pattern 17015 is triangular; wherein, the first fixedview pattern 17015 is the largest, the second fixedview pattern 17015 is the next, and the third fixedview pattern 17015 is the smallest; at least a part of the three firstoptical devices 17013 is transparent, and specifically, the second firstoptical device 17013 and the third firstoptical device 17013 are transparent in the forward projection range of the largest fixedpattern 17015, that is, the firstfixed pattern 17015; of course, the second firstoptical device 17013 and the third firstoptical device 17013 may also be light-transmissive as a whole; thus, the light emitted from the first fixedview pattern 17015 can enter the eye of the subject through the second firstoptical device 17013 and the third firstoptical device 17013, and the light emitted from the second fixedview pattern 17015 can enter the eye of the subject through the third firstoptical device 17013; the three fixation-view patterns 17015 have different sizes, and the eyes of the testee observe the outline or part of one fixation-view pattern 17015, so as to perform fixation.

As described above, the plurality of groups offixation light sources 1701 of the fixationoptical device 170 of the present embodiment are arranged at set intervals along the optical path so that the corresponding plurality of groups offixation patterns 17015 are at positions corresponding to different dioptres. The fixedview patterns 17015 of each group are different in size and are arranged along the optical path. Since the plurality of sets of light emittingdevices 17011 laterally illuminate the respective sets of fixedpatterns 17015, the fixedpatterns 17015 become secondary light sources. Thus, the eye of the testee with different dioptres can naturally see thefixation pattern 17015 corresponding to the dioptres along the light path, so that the focusing by using a focusing motor is avoided, the structure of the fixation optical device can be simplified, the number of adjusting parts is reduced, and the cost is reduced.

In other embodiments, the plurality offixation patterns 17015 are each different in size, but the same in shape; alternatively, referring to fig. 12, the three fixedview patterns 17015 are all the same in size and shape, and the projections of the three fixedview patterns 17015 on a projection plane perpendicular to the optical path are staggered from each other by at least a portion, so that each fixed view pattern can be observed along the optical path by at least a portion; in this way, the eye E can observe at least a part of any one of thefixation patterns 17015 along the optical path, thereby performing fixation.

Referring to fig. 7, the fixationoptical device 170 of the present embodiment further includes the aforementionedobjective lens 1311, a pre-dichroic 1309, arelay lens 1905, and a thirddichroic mirror 1907. That is, the fixationoptical device 170 shares theobjective lens 1311 and the frontdichroic mirror 1309 with the opticalcoherence tomography apparatus 110, and shares therelay lens 1905 and the thirddichroic mirror 1907 with theiris imaging apparatus 190.

The frontdichroic mirror 1309 can also transmit fixation light having a wavelength of 550nm emitted from thefixation light source 1701 in the fixationoptical device 170.

In the system setting, therelay lens 1905 and theobjective lens 1311 are brought into confocal with each other to constitute a keplerian telescope system. The second fixedview pattern 17015 is disposed in an object focal plane of thefifth lens 1703. Thefirst fixing pattern 17015 and thethird fixing pattern 17015 are disposed on both sides of thesecond fixing pattern 17015.

Light from thefixation light source 1701 passes through thefifth lens 1703, passes through the thirddichroic mirror 1907, therelay lens 1905, and the frontdichroic mirror 1309 for transmission, and then enters the eye E through theobjective lens 1311. Finally, the internal fixation index is projected to the fundus of the eye E of the subject.

The examiner fixes the head of the examinee using a chin rest (not shown), and fixes the examinee's eyes E by fixing the fixation mark, i.e., the fixation pattern, of the fixationoptical device 170. Then, the examiner controls the movement of the chin rest device, the probe, and the like by the operation lever while observing the display screen of thecomputer 1143, so that the iris of the eye E enters theimaging device 1911 and the iris image appears on the display screen of thecomputer 1143.

The present embodiment also provides an optical coherence tomography method using the ophthalmic measurement system of the present embodiment. In this embodiment, thecomputer 1143 is the main body for executing the method, i.e., thecomputer 1143 is used for executing the method.

The waveform output by thelight source 1101 is shown in fig. 8. As mentioned above, the light scattered back by the sample interferes with the light returned by thereference arm 112 in thefiber coupler 1103, and the interference signal is transmitted to the detectingdevice 1141 to form the front-back section interference spectrum signal. The interference spectrogram of the front section and the back section is shown in FIG. 9. After receiving the front and rear interference spectrum signals sent by thedetection device 1141, thecomputer 1143 divides the interference spectrum into two wavelength bands, to obtain a left half interference spectrum and a right half interference spectrum in fig. 9, and performs operations such as fourier transform on the two interference spectrum signals, to obtain two OCT images of the front and rear segments.

If a spectral domain OCT system is used, thedetection device 1141 is a spectrometer, and receives the front-section and rear-section interference spectra transmitted by theoptical fiber coupler 1103 and transmits the front-section and rear-section interference spectra to thecomputer 1143. Thecomputer 1143 divides the interference spectrum of the front and rear sections into two long and short wavelength bands through operation processing, and performs fourier operation and the like on the two long and short interference spectrum signals respectively, thereby obtaining two OCT images of the front and rear sections.

If a swept OCT system is used, thesource 1101 is a swept source and thedetector 1141 is a detector. The swept spectrum received by thedetection device 1141 is subjected to photoelectric conversion to obtain front and rear section interference spectrum signals. Thedetector 1141 transmits the interference spectrum signals of the front and rear sections to thecomputer 1143. Thecomputer 1143 divides the front and rear interference spectra into two long and short wavelength bands through operation processing, and performs fourier operation and the like on the two long and short wavelength interference spectrum signals respectively, thereby obtaining two front and rear OCT images.

Therefore, no matter a frequency domain OCT system or a frequency sweeping OCT system, the full real-time front and rear section OCT images can be obtained through the spectrum splitting and the combination of the front and rear section OCT sample arm light paths. The present embodiment is also not limited to the application to frequency-domain OCT systems and swept-frequency OCT systems.

It will be understood by those skilled in the art that all or part of the processes in the methods for implementing the embodiments may be implemented by hardware related to instructions of a computer program, which may be stored in a computer-readable storage medium, and when executed, may include processes such as those of the embodiments of the methods. And the aforementioned storage medium includes: various media capable of storing program codes, such as ROM or RAM, magnetic or optical disks, etc.

To achieve that the referencearm beam splitter 1123 is transmissive to light of a first wavelength and reflective to light of a second wavelength, the referencearm beam splitter 1123 is desirably coated as shown in FIG. 10 for wavelengths less than λ₀Is totally transmitted (or totally reflected) and has a wavelength greater than λ₀Is totally reflected (or totally transmitted). The actual waveform is never at the theoretical limit and a transition zone exists between transmission and reflection as shown in fig. 11. Therefore, theprobe 1141 and thecomputer 1143 perform the above-described OCT correlation operation on the spectrum in the wavelength band smaller thanλ 0 —Δ λ 1 and the spectrum in the wavelength band larger thanλ 0+ Δ λ 2, respectively.

The spectrum between (lambda 0-delta lambda 1) and (lambda 0 plus delta lambda 2) is a transition band,lambda 0 is the critical wavelength of total reflection and total transmission which is ideally set, but the actual coating effect cannot reach the ideal state. In the actual coating process, a transition state exists between total reflection and total transmission. The spectrum of the set < (λ 0- Δ λ 1) band will be totally transmitted, while the spectrum of the < (λ 0+ Δ λ 2) band will be totally reflected. Therefore, the critical point of total transmission is (λ 0- Δ λ 1) and the critical point of total reflection is (λ 0+ Δλ 2) in actual coating. (λ 0- Δ λ 1) is the actual total transmission starting wavelength; (λ 0+ Δ λ 2) is the actual total reflection termination wavelength; thedelta lambda 1 is the deviation amount of the actual total transmission starting wavelength and the ideally setcritical wavelength lambda 0 of total reflection and total transmission; Δ λ 2 is the deviation of the actual total reflection termination wavelength from the ideally setcritical wavelength λ 0 for total reflection and total transmission.

As described above, theiris imaging apparatus 190 and the opticalcoherence tomography apparatus 110 share theobjective lens 1311 and the pre-dichroic 1309. The fixationoptical device 170 shares theobjective lens 1311 and the pre-dichroic 1309 with the opticalcoherence tomography apparatus 110, and shares therelay lens 1905 and the thirddichroic mirror 1907 with theiris imaging apparatus 190. The opticalcoherence tomography device 110 can obtain OCT images of the thickness of the retina, the cornea, and the anterior and posterior surfaces of the crystalline lens, thereby obtaining important parameters of the human eye structure, such as the anterior and posterior surface curvature of the cornea, the thickness of the cornea, the anterior chamber depth, the thickness of the crystalline lens, the anterior and posterior surface curvature of the crystalline lens, and the like. The front and back sections of OCT images formed by the opticalcoherence tomography apparatus 110 can be combined with the optical path difference of the optical path of the front and back sectionOCT sample arm 130 to obtain the data of the axial length of the human eye and other important parameters of the human eye structure. Theiris imaging device 190 can obtain important parameters of the human eye structure such as the white-to-white distance, the pupil diameter and the like. The anterior segment and the posterior segment OCT images are acquired by one-time measurement, the detection of a plurality of human eye key parameters such as cornea, anterior chamber depth, eye axis length, corneal curvature, white to white and the like is realized, the operation is convenient, the measurement speed can be improved, the efficiency can be improved, and the experience of a tested person can be improved.

Thescanning device 1305 only needs to realize the scanning function without switching the optical path, and the rotation angle of thescanning device 1305 is small and the speed is high. The front section and the rear section are completely scanned and imaged simultaneously, scanning of dozens of images can be realized per second, the speed is high, the influence of irregular movement of human eyes can be avoided, and therefore the axial length of the human eyes can be accurately measured. And inaccurate measurement of the eye axis length caused by eye shake in the light path switching process can be avoided.

The ophthalmologic measurement system of the present embodiment can be used as a front-back section imaging OCT system. By adopting a spectrum splitting technology, adopting a single detection light source and a single signal detection device, the optical path switching mechanism is not needed, the complete simultaneous detection of the front section and the rear section is realized, and the rapid OCT imaging of different parts of human eyes is realized, thereby realizing the detection of samples with different depths, improving the detection range of an OCT system, using fewer motion mechanisms and having low cost. On the basis of OCT imaging of different parts of human eyes, the rapid and accurate measurement of the axial length of the eye, the anterior chamber depth, the lens thickness and the like can be realized without moving a reference arm. The front and rear sections of the spectral detection light path are realized, so that the front and rear sections of human eyes adopt different light paths for detection, and the signal-to-noise ratio and the imaging quality of each detection are improved.

The foregoing is a more detailed description of the invention in connection with specific/preferred embodiments and is not intended to limit the practice of the invention to those descriptions. It will be apparent to those skilled in the art that various substitutions and modifications can be made to the described embodiments without departing from the spirit of the invention, and these substitutions and modifications should be considered to fall within the scope of the invention.

Claims (9)

1. An optical device for fixation, comprising: comprises a plurality of groups of vision fixation light sources arranged along a light path according to a set interval;

the fixation light source comprises a light emitting device, a first optical device and a fixation pattern arranged on the first optical device;

the light emitting device is used for irradiating the fixation pattern along the lateral direction of the first optical device so that the fixation pattern becomes a secondary light source;

the fixation patterns of the multiple groups of fixation light sources are arranged along the optical path, and at least one of the multiple fixation patterns can be observed along the optical path at least partially; the multiple groups of fixation patterns of the fixation light source are arranged along the light path at set intervals, the corresponding multiple groups of fixation patterns are positioned at positions corresponding to different dioptric positions, the sizes of the multiple fixation patterns are different, or the multiple fixation patterns are the same in size and the projections of the multiple fixation patterns on a projection plane perpendicular to the light path are staggered by at least one part.

2. The fixation optical device according to claim 1, wherein: the fixation pattern can scatter light; the material of the first optical device is glass, and the vision fixing pattern is a frosted pattern arranged on the first optical device.

3. An ophthalmic measurement system, characterized by: comprising a fixation optical device according to any one of claims 1 to 2.

4. An ophthalmic measurement system according to claim 3, characterized in that: the device also comprises an optical coherence tomography device and an iris camera device; the optical coherence tomography device comprises a sample arm, wherein the sample arm comprises an ocular objective lens and a front dichroic mirror which are sequentially arranged along the light incidence direction;

the iris image pick-up device comprises the eye objective lens, the front dichroic mirror, a relay lens and a third dichroic mirror, wherein the relay lens and the third dichroic mirror are sequentially arranged along the incident direction of light and are positioned behind the front dichroic mirror;

the fixation optical device further comprises the ocular objective, the pre-dichroic mirror, the relay lens and the third beam splitter.

5. An ophthalmic measurement system according to claim 4, characterized in that: the optical coherence tomography device also comprises a light source, an optical fiber coupler, a reference arm, a detection device and a computer;

the light source can provide light to the sample arm and the reference arm through the fiber coupler;

the detection device is used for detecting the light output by the optical fiber coupler;

the computer is used for processing the data output by the detection device.

6. An ophthalmic measurement system according to claim 5, characterized in that: the reference arm comprises a reference arm light path lens, a reference arm spectroscope, a posterior eye reference arm reflector and an anterior eye reference arm reflector, wherein the reference arm light path lens, the reference arm spectroscope, the posterior eye reference arm reflector and the anterior eye reference arm reflector can reflect reflected light of the reference arm spectroscope are sequentially arranged along the incident direction of the light;

the reference arm beamsplitter is transmissive to light of a first wavelength and reflective to light of a second wavelength, the first wavelength being a different wavelength than the second wavelength; the anterior ocular segment reference arm mirror may reflect light of the first wavelength; the posterior eye reference arm mirror may reflect the light of the second wavelength;

the light with the first wavelength reflected by the anterior ocular segment reference arm reflector of the detected eye can interfere with the light with the first wavelength reflected by the anterior ocular segment reference arm reflector in the optical fiber coupler after passing through the ocular objective lens;

the light with the second wavelength reflected by the eye posterior segment reference arm reflector can interfere with the light with the second wavelength reflected by the eye posterior segment reference arm reflector in the optical fiber coupler after passing through the eye objective lens.

7. An ophthalmic measurement system according to claim 6, characterized in that: the sample arm further comprises a scanning device arranged in the direction of light incidence and located behind the pre-dichroic mirror.

8. An optical coherence tomography method, characterized by: using the ophthalmic measurement system of claim 7 or 8; the optical coherence tomography method comprises the following steps:

receiving interference spectrum signals of front and rear sections;

dividing the front and rear section interference spectrum into a long waveband and a short waveband to obtain a long-short waveband interference spectrum and a short-short waveband interference spectrum;

and respectively operating the long and short sections of interference spectrum signals to obtain two optical coherence tomography images of the front section and the rear section.

9. A computer-readable storage medium, having stored thereon program instructions, which, when executed by a processor of a computer, cause the processor to carry out the method according to claim 8.

Images