JP2005348755A - Ophthalmologic measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ophthalmologic measuring device capable of measuring/obtaining various biological information by one unit. <P>SOLUTION: The ophthalmologic measuring device measures the refractive power and the length of ocular axis of an examined eye non-contact. The ophthalmologic measuring device comprises a measuring light irradiation optical system for applying the light with low coherent length to the examined eye, a light receiving optical system for receiving the reflection light from the fundus oculi of the examined eye by the light with low coherent length applied to the examined eye, a refractive power measuring means for finding the refractive power of the examined eye based on the state of receiving the reflection light received by the light receiving optical system, a reference light irradiation optical system for making the reflection light from the anterior ocular segment of the examined eye obtained by the irradiation of the light with low coherent length the reference light, an interference optical system for synthesizing the reference light obtained by the reference light irradiation optical system and the reflection light from the fundus oculi obtained by the measuring light irradiation optical system to interfere, and dispersing the obtained interference light into frequency components to receive the light, and an in-vivo dimension measuring means for measuring the in-vivo dimensions of the examined eye based on the receiving light signal obtained by the interference optical system. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ophthalmologic measurement apparatus that measures biological information of an eye to be examined without contact.

Conventionally, intraocular lens design, medical research, and the like have been performed by acquiring biological information of the eye. As an apparatus for measuring such biological information of the eye to be examined, for example, an ophthalmologic measurement apparatus that measures the axial length and refractive power of the eye to be examined in an optical non-contact manner is known. In a device that measures the axial length and refractive power of the eye to be examined in a non-contact manner, the interference is generated by combining the reflected light from the fundus and the reflected light from the reference surface provided in the device. The axial length of the eye to be examined is calculated by obtaining the distance from the position to the fundus of the eye to be examined, and further obtaining the distance from the reference position to the cornea of the eye to be examined by another optical system. An apparatus is known in which the refractive power is determined by moving the focusing lens movable in the optical axis direction for correcting the refractive power in the optical axis direction and moving the focusing lens (see Patent Document 1).
JP-A-7-255684

However, the conventional ophthalmic measuring apparatus as described above can obtain only two types of biological information, that is, refractive power and axial length. The biological information of the eye to be examined includes various information such as refractive power, axial length, corneal thickness, crystalline lens thickness, anterior chamber depth, and the like. There is an apparatus that can obtain such biological information at a time. It is desired.
An object of the present invention is to provide an ophthalmologic measuring apparatus capable of measuring and acquiring various biological information of an eye with a single unit in view of the above-described problems of the prior art.

In order to solve the above problems, the present invention is characterized by having the following configuration.
(1) In an ophthalmologic measurement apparatus that measures the refractive power and the axial length of the eye to be examined in a non-contact manner, the measurement light irradiation optical system that irradiates the eye to be examined with light having a low coherent length, and the light that is emitted toward the eye to be examined A light-receiving optical system that receives reflected light from the fundus of the eye to be examined by the low-coherent length light, and a refractive power measurement unit that obtains the refractive power of the eye to be examined based on the light-receiving state of the reflected light received by the light-receiving optical system A reference light irradiation optical system using, as a reference light, reflected light from the anterior eye part of the eye to be examined obtained by irradiation with light of the low coherent length, the reference light obtained by the reference light irradiation optical system, and the measurement Interference optical system that synthesizes and interferes with the reflected light from the fundus of the eye to be inspected obtained by the light irradiation optical system, and obtains the interference light obtained by splitting the obtained interference light into frequency components, and obtained by the interference optical system Eye to be examined based on received light signal And in-vivo dimension measuring means for measuring the in-vivo dimension.
(2) In the ophthalmic measurement apparatus according to (1), the interference optical system includes an optical path length varying unit that varies an optical path length of the reference light or the measuring light, and a spectral unit that causes the combined light beam to be split into the frequency components. And an optical member for causing the light receiving element to receive each light beam split by the spectroscopic means, and the in-vivo dimension measuring means analyzed the received light signal output from the light receiving element using Fourier transform The axial length of the eye to be examined is measured based on the analysis result and the amount of change of the optical path length varying means, and the in-vivo dimensions of the anterior eye portion of the eye to be examined are measured based on the analysis result. To do.
(3) The ophthalmologic measurement apparatus according to (2) includes a refractive power correction unit that corrects the refractive power of the eye to be examined based on the refractive power of the eye to be examined obtained by the refractive power measurement unit.
(4) The ophthalmic measuring apparatus according to any one of (1) to (3) includes a scanning unit that scans the eye to be inspected with the reference light irradiation optical system toward the eye to be examined, and the scanning unit. A light reception signal obtained by the interference optical system that receives a combined light beam of the reference light beam and the reflected light beam from the fundus of the eye to be examined is analyzed using Fourier transform, and the analysis is performed based on the analysis result. Image processing means for obtaining a cross-sectional image of the eye to be examined, and display means for displaying the cross-sectional image obtained by the image information processing means.
(5) Measuring light irradiation optical system for irradiating measurement light toward the fundus of the subject to be examined and light reflected from the fundus of the eye to be examined are received, and the refractive power of the eye to be examined is obtained based on the light receiving state of the received reflected light Refracting power measuring means, refracting power correcting means for correcting the refracting power of the subject eye based on the refracting power of the subject eye obtained by the refracting power measuring means, and irradiating the subject eye with light of low coherent length, The reflected light from the fundus of the low-coherent length light corrected in the light condensing state on the fundus of the eye to be examined by the refractive power correcting means and the reflected light of the low-coherent length light reflected from the anterior eye part. An interference optical system for synthesizing and interfering and condensing the obtained interference light on the light receiving surface of the light receiving element, and in vivo of the eye to be inspected based on the light reception signal by the interference light collected on the light receiving surface of the light receiving element In vivo dimension measuring means for measuring dimensions. And features.

  According to the present invention, it is possible to obtain various biological information of the eye that has been conventionally measured by a plurality of devices, and to shorten the measurement time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of an optical system of an axial length measuring apparatus having a refractive power measuring function, which is one type of ophthalmic measuring apparatus used in the present embodiment. The optical system shown in FIG. 1 includes a measurement light projection optical system, a refractive power measurement optical system, a reference light projection optical system, an interference signal detection optical system, a target projection optical system, and an observation optical system. Note that the ophthalmic measurement apparatus according to the present embodiment also has an alignment optical system for positioning the apparatus in a predetermined relationship with respect to the eye to be examined, but has been conventionally used for an objective eye refractive power apparatus or the like. Since an optical system similar to a known alignment optical system may be used, the description thereof is omitted.

<Measurement light projection optical system>
A measuring light projecting optical system 100 shown in FIG. 1 includes a light source 1, a collimator lens 2, a beam splitter 3, a condenser lens 4, a relay lens 5, a diaphragm 6, a hall mirror 7, a beam splitter 8, an objective lens 9, and a beam. A splitter 10 is used.

  The light source 1 is a light source that emits low-coherent infrared light such as SLD (Super luminescent Diode). The low coherent light emitted from the light source 1 is converted into a parallel light beam by the collimator lens 2 and then transmitted through the beam splitter 3. The light beam that has passed through the beam splitter 3 forms an intermediate image (condensing point A) on the optical axis L1 by the condensing lens 4, and then passes through the relay lens 5 and the opening of the hall mirror, and is condensed once. Then, the light is condensed on the fundus of the eye E through the beam splitter 8, the objective lens 9, and the beam splitter 10.

<Optical power measurement optical system>
A refractive power measuring optical system 200 shown in FIG. 1 includes a beam splitter 10, an objective lens 9, a beam splitter 8, a hall mirror 7, a relay lens 11, a mirror 12, a diaphragm 13, a collimator lens 14, and a beam splitter from the front of the eye E. 15, a ring lens 16, and a light receiving element 17 having sensitivity in the infrared region. The measurement light projecting optical system 100 shares the hall mirror 7 to the beam splitter 10.

The reflected light (measurement light) of the light beam collected on the fundus of the eye E by the measurement light projection optical system 100 is reflected by the Hall mirror 7 through the beam splitter 10, the objective lens 9, and the beam splitter 8. The hall mirror 7 reflects fundus reflected light from the eye E, and unnecessary corneal reflected light passes through the opening.
The fundus reflection light reflected by the hall mirror 7 passes through the relay lens 11, is bent by the mirror 12, and is then condensed (condensing point B) at the position of the diaphragm 13. Thereafter, the reflected light is converted into a parallel light beam by the collimator lens 14, and then a part of the reflected light is reflected by the beam splitter 15, and is received by the two-dimensional light receiving element 17 through the ring lens 16.

  Note that the condensing point A by the condensing lens 4 of the measurement light projecting optical system 100 and the condensing point B at the position of the stop 13 which is the front focal position of the collimator lens 14 are connected to the objective lens 9 and the relay lenses 5 and 11. Through the eye fundus of the eye E to be examined. Further, the condenser lens 4, the aperture 13, the collimator lens 14, the beam splitter 15, the ring lens 16, and the light receiving element 17 shown in FIG. 1 are installed on a drivable stage 18, and the stage 18 is shown in FIG. It can be moved in the optical axis direction by the driving means 53 shown in FIG.

  Further, the ring lens 16 is placed at the back focal position of the collimator lens 14 and maintains a conjugate relationship with the pupil of the eye E regardless of the movement position of the stage 18 by the driving means 19. Furthermore, the light receiving element 17 is at the focal position of the ring lens 16 and has a conjugate relationship with the fundus of the eye E to be examined. The ring lens 16 is formed by forming a cylindrical lens in a ring shape on a flat plate, and a coating for light shielding is applied except for the ring portion. When a parallel light beam enters the ring lens 16, a ring image having substantially the same size as the ring lens 16 is condensed at the focal position (the light receiving surface of the light receiving element 17).

<Reference light projection optical system>
A reference optical system 300 shown in FIG. 1 includes a light source 1, a collimator lens 2, a beam splitter 3, a mirror 19, a beam splitter 20, a condenser lens 21, a mirror 22, a beam splitter 8, an objective lens 9, and a beam from the light source side. A splitter 10 is used. The measurement light projecting optical system 100 shares the light source 1 to the beam splitter 3 and the beam splitter 8 to the beam splitter 10.
After the low-coherent light emitted from the light source 1 passes through the collimator lens 2, a part of the light beam is reflected by the beam splitter 3 and travels to the mirror 19 disposed on the optical axis L2. The light beam reflected by the mirror 19 passes through the beam splitter 20 and is then condensed by the condenser lens 21 on the optical axis L2. The light beam condensed on the optical axis L2 is reflected by the mirror 22 and then reflected by the beam splitter 8 so as to be coaxial with the optical axis L1, passes through the objective lens 9 and the beam splitter 10, and passes through the eye E. Focus on the cornea.

<Interference signal detection optical system>
An interference signal detection optical system 400 shown in FIG. 1 receives an optical system for receiving reflected light (measurement light) from the fundus of the eye E and a reflected light (reference light) from the cornea of the eye E. Optical system.

  The optical system that receives the reflected light from the fundus includes a beam splitter 10, an objective lens 9, a beam splitter 8, a hall mirror 7, a relay lens 11, a mirror 12, an aperture 13, a collimator lens 14, and a beam splitter from the front of the eye E to be examined. 15, a beam splitter 26, a mirror 27, a condenser lens 28, an expander lens 29, a grating mirror (diffraction grating) 30, a condenser lens 31, a cylindrical lens 32, and a light receiving element 33. The light receiving element 33 uses a one-dimensional element having sensitivity in the infrared region. The measurement light projecting optical system 100 shares the beam splitter 10 to the beam splitter 15.

  As described above, the reflected light of the light beam collected on the fundus of the eye E by the measurement light projection optical system 100 passes through various optical members of the refractive power measurement optical system 200 and then is partially reflected by the beam splitter 15. Reflected light is transmitted. The reflected light that has passed through the beam splitter 15 is further reflected by the mirror 27 via the beam splitter 26 disposed on the optical axis L3, and once condensed through the condenser lens 28. The reflected light collected by the condensing lens 28 is expanded in diameter by the expander lens 29 and then split into frequency components by the grating mirror 30. The reflected light split into frequency components is condensed on the light receiving surface of the light receiving element 33 through the condenser lens 31 and the cylindrical lens 32. The beam diameter after passing through the expander lens 29, the grating interval and incident angle of the grating mirror, the condensing lens 28, and the light receiving element 33 are optimized in consideration of the measurement range and resolution in the optical axis direction of the eye to be examined. .

  An optical system for receiving reflected light from the cornea of the eye E (hereinafter referred to as reference light) includes a beam splitter 10, an objective lens 9, a beam splitter 8, a mirror 22, Optical lens 21, beam splitter 20, prism 23, mirrors 24 and 25, beam splitter 26, mirror 27, condenser lens 28, expander lens 29, grating mirror 30, condenser lens 31, cylindrical lens 32, and light receiving element 33 Configured. The prism 23 can be moved in the direction of the arrow shown by the driving means 54 shown in FIG. 2 so that the optical path length through which the reference light passes can be changed.

  A part of the reference light is reflected by the beam splitter 8 after passing through the beam splitter 10 and the objective lens 9. The reference light reflected by the beam splitter 8 passes through the mirror 22 and the condenser lens 22, is reflected by the beam splitter 20, and travels toward the prism 23. The reference light returned by the prism 23 travels to the beam splitter 26 via the mirrors 24 and 25. The reference light reflected by the beam splitter 26 is combined with the reflected light from the fundus. The reference light combined with the reflected light from the fundus passes through the mirror 27, the condensing lens 28, and the expander lens 29 in the same manner as the reflected light from the fundus, and then is split into frequency components by the grating mirror 30 to be a cylindrical lens. Then, the light is condensed on the light receiving element 33. Thus, the spectrometer unit is formed by the grating mirror 30, the condensing lens 31, the cylindrical lens 32, and the light receiving element 33. The light receiving surface of the light receiving element 33 has a conjugate relationship with the fundus of the eye E and the cornea. The cylindrical lens 32 serves to widen the diameter of the light beam in the width direction of the light receiving element 33, and is used to receive the light beam on the light receiving surface regardless of the installation error of the light receiving element 33.

<Target projection optical system / observation optical system>
1 includes a light source 34 such as an LED that emits visible light, a target plate 35 on which a predetermined target is formed, a relay lens 36, a beam splitter 37, an objective lens 38, and a beam splitter 10. Become. The visible light beam emitted from the light source 34 illuminates the target plate 35 from the back. The light beam that has passed through the target plate 35 forms an image on the fundus of the eye E through the relay lens 36, the beam splitter 37, the objective lens 38, and the beam splitter 10. When the apparatus is aligned so as to have a predetermined positional relationship with the eye E, the target plate 31 and the fundus of the eye E have a conjugate relationship. In addition, the light source 34 and the target plate 35 can be moved in the optical axis direction by the driving means 55, and the subject's eye can be fixed or the position of the target plate can be changed to measure the refractive power of the subject's eye. Or apply an adjustment load.

  The observation optical system includes a beam splitter 10, an objective lens 38, a beam splitter 37, an imaging lens 39, and a light receiving element 40 having sensitivity in the infrared region from the front of the eye to be examined. Note that the pupil position of the eye E and the light receiving element 40 have a conjugate positional relationship. In addition, in order to illuminate the eye E, 41 is an infrared LED for illuminating the eye to be examined.

FIG. 2 is a block diagram showing a control system in the ophthalmic measurement apparatus used in the present embodiment.
A control unit 50 performs drive control of the apparatus according to the present embodiment. The control unit 50 is connected to the light receiving element 17, the light receiving element 33, the light receiving element 40, a monitor 51, an arithmetic processing unit 52, driving means 53 to 55, a storage unit 56, and the like. The driving means 53 to 55 use pulse motors or the like, and can detect the driving amount by each driving means. In addition, the arithmetic processing unit 52 obtains biological information such as refractive power and axial length of the eye E by calculation based on information obtained by the light receiving element, driving means, etc., and forms a cross-sectional image of the eye to be examined. Used to do. Further, the obtained measurement value is stored in the storage unit 56.

The operation of the apparatus having the above configuration will be described below.
While looking at the monitor 51 shown in FIG. 1, the examiner moves the apparatus in the vertical and horizontal directions and the front and rear direction using an operation unit such as a joystick (not shown) to place the apparatus in a predetermined positional relationship with the eye E to be examined. . In the present embodiment, the light receiving surface of the light receiving element 36 and the pupil position of the eye E to be examined are in a conjugate relationship. The examiner causes the subject to fixate the target projected by the target projection optical system shown in FIG. 1, and obtains biological information of the eye E using a measurement button (not shown).

  When the measurement button is pressed, the control unit 50 drives the driving unit 55 to move the light source 34 and the target plate 35 in the optical axis direction so as to be in a cloudy state so that the eye E is not adjusted. To do. Further, the control unit 50 emits low coherent light from the light source 1. The low-coherent light emitted from the light source 1 is divided into two directions by the beam splitter 3 shown in FIG. 1, and then passes through the measurement light projection optical system 100 and the reference light projection optical system 300 described above. Focuses on the fundus and cornea, respectively.

  The reflected light of the light beam collected on the fundus of the eye E is reflected by the Hall mirror 7 after passing through the beam splitter 10, the objective lens 9 and the beam splitter 8 shown in FIG. 1. The fundus reflection light reflected by the hall mirror 7 passes through the relay lens 11, the mirror 12, the diaphragm 13, and the collimator lens 14, and then a part thereof is bent downward by the beam splitter 15 and received through the ring lens 16. Light is received by the element 17.

FIG. 3 is a schematic view showing a state in which reflected light from the fundus is received by the light receiving element 17 through the ring lens 16. For example, when the eye E is a normal eye, the reflected light that has passed through the collimator lens 14 passes through the ring lens 16 as a parallel light flux as shown in FIG. At this time, the ring image R ₁ received by the light receiving element 17 through the ring lens 16 has substantially the same size as the ring lens 16. When the eye E is a myopic eye, the reflected light that has passed through the collimator lens 14 becomes convergent light as shown in FIG. 3B and passes through the ring lens 16. At this time, the ring image R ₂ received by the light receiving element 17 through the ring lens 16 becomes thicker than the ring image R ₁ shown in FIG. When the eye E is a hyperopic eye, the reflected light that has passed through the collimator lens 14 becomes convergent light as shown in FIG. 3C and passes through the ring lens 16. At this time, the ring image R ₃ received by the light receiving element 17 through the ring lens 16 becomes thicker and has a larger diameter than the ring image R ₁ shown in FIG.

  The arithmetic processing unit 52 performs arithmetic processing based on the amount of change between the light receiving state when the eye to be examined is a normal eye and the light receiving state actually detected by the light receiving element 17 to obtain the refractive power of the eye E to be examined. . Further, the arithmetic processing unit 52 is a stage for the measurement light projected toward the fundus from the calculated refractive power value or the light receiving state of the light receiving element 17 to be most condensed (best focus) on the fundus of the eye E to be examined. 18 positions are calculated. The arithmetic processing unit 52 sends the calculated position information of the stage 18 that is the best focus to the control unit 50. The control unit 50 drives the driving means 53 based on the received position information to move the stage 18 and corrects the refractive power for the eye E. By correcting the refractive power for the eye E in this way, it is possible to correct the condensing state of the measurement light on the fundus according to the refractive power, and to obtain an interference signal with a good S / N ratio. .

  In the present embodiment, the refractive power of the eye E is determined based on the light receiving state of the ring image received by the light receiving element 17, but the present invention is not limited to this, and the measurement light is condensed on the fundus. Therefore, the refractive power of the eye E can be obtained in consideration of the position of the stage 18 that is the best focus position and the light receiving state of the ring image at that time. The light reception state information of the ring image received by the light receiving element 17 is used to calculate the position information of the stage 18 for obtaining the best focus, and the refractive power of the eye to be examined is determined from the reference position of the stage 18. It can also be obtained based on the amount of movement. The obtained refractive power value of the eye E is stored in the storage unit 56 and displayed on the monitor 51.

  As the refractive power of the eye E is corrected by the movement of the stage 18, the measurement light is efficiently condensed on the fundus of the eye E. The reflected light from the fundus is finally condensed on the light receiving element 33 by the optical system for receiving the measurement light in the interference signal detecting optical system 400 shown in FIG. Further, the reference light (corneal reflection light of the eye E) is finally condensed on the light receiving element 33 by the optical system for receiving the reference light in the interference signal detection optical system 400. Note that, as described above, the light beam obtained by combining the reflected light from the fundus and the reference light is split into frequency components by the grating mirror 30, and is condensed on the light receiving element 33 through the condenser lens 31 and the cylindrical lens 32. Will be. The light receiving element 33 receives the reflected light separated into frequency components and outputs the interference intensity for each frequency component. The arithmetic processing unit 52 monitors the interference intensity obtained by the measurement light received by the light receiving element 33 and the reference light.

  On the other hand, the control unit 50 uses the driving unit 54 to move the prism 23 shown in FIG. 1 from the reference position indicated by the solid line (here, the position where the reference optical path is the shortest), thereby setting the optical path length of the optical system through which the reference light passes. Change it. In this embodiment, during the measurement of the axial length, the prism 23 is reciprocated several times to several tens of times per second. However, the present invention is not limited to this. It may be only moved in one direction. Since the measurement light and the reference light used in this embodiment are low-coherent light, when the optical path length of the measurement light is equal to the optical path length of the reference light, it is obtained by combining the measurement light and the reference light. The signal intensity of the interference light to be generated is the strongest. The reference light received by the light receiving element 33 includes reflected light from phase objects such as the back surface of the cornea and the front and back surfaces of the crystalline lens, in addition to the reflected light from the surface of the cornea. Accordingly, the interference signal received by the light receiving element 33 is received as a function of frequency due to interference between these and the fundus reflection light.

  The arithmetic processing unit 52 analyzes the detection signal output from the light receiving element 33 when the intensity of the interference signal becomes the highest using Fourier transform. Since the interference light includes reflected light from each phase object (for example, the front and back surfaces of the cornea, the front and rear surfaces of the lens, the retina, etc.) in the eye E, the cornea in the eye E is subjected to Fourier transform, Depth information of each phase object such as a crystalline lens can be obtained. The arithmetic processing unit 52 obtains the axial length of the eye E from the position information of the front surface of the cornea based on the position of the prism obtained by the computation and the movement amount of the prism (or the driving amount of the driving means 54). Further, other in-vivo dimensions (for example, in-vivo dimensions such as corneal thickness, anterior chamber depth, and lens thickness) are directly obtained from the obtained depth information of each phase object. Information on the obtained in-vivo dimensions is stored in the storage unit 56 and displayed on the monitor 51. In this embodiment, the optical path length of the reference light is changed by moving the prism placed in the reference optical path so that the optical path length of the measurement light and the optical path length of the reference light are equal. The optical path length of the measurement light can be changed.

  In order to obtain the axial length more accurately, in the optical system shown in FIG. 1, a position conjugate between the collimator lens 14 and the condensing lens 27 and the pupil of the eye E to be examined, or an objective lens What is necessary is just to arrange | position the optical member for astigmatism correction which consists of a combination of a some cylinder lens in the position substantially conjugate with the pupil of the eye E to be examined between Hall mirrors. As the astigmatism correcting optical member, for example, a Stokes cross cylinder formed by a combination of two cylinder lenses can be used. When the eye E has astigmatism, the ring image received by the light receiving element 17 through the ring lens 16 has an elliptical shape. Therefore, the light receiving state of the ring image is analyzed using the arithmetic processing unit 42. Thus, the astigmatism power and the astigmatism axis angle can be obtained. The above-described astigmatism correcting optical member is arranged so as to cancel the astigmatism component of the eye E based on the obtained astigmatism power and astigmatism axis angle of the eye E. With such a configuration, even if the eye to be examined has an astigmatism component, the reflected light from the fundus can be efficiently condensed on the light receiving element 33 and the measurement accuracy can be improved.

In this embodiment, the reference light is focused on the corneal surface. However, the present invention is not limited to this, and reflected light from a phase object (cornea, crystalline lens, etc.) in the eye to be examined is included in each frequency component. It is only necessary that the light receiving element receives the light in a spectral state. For example, the condensing position of the reference light can be set as the pupil position of the eye E to be examined.
In this embodiment, a grating mirror (diffraction grating) is used as a spectroscopic means for splitting the combined light of the measurement light and the reference light into each frequency component. However, the present invention is not limited to this. Other spectroscopic means such as an optical element can also be used.
Furthermore, in this embodiment, a ring image is formed on the light receiving element in order to obtain the refractive power of the eye to be examined, but the present invention is not limited to this. For example, the reflected light from the fundus is divided into several points via an optical member and collected on the light receiving element, and the refractive power is calculated based on the light receiving state of the received light image. Any configuration may be used as long as the refractive power is obtained by detecting a change state of the received light image such as a change in position or shape of the received light image.

  As described above, in the ophthalmologic measurement apparatus according to the present embodiment, it is assumed that in vivo dimensions such as refractive power and axial length can be obtained at one time, but further scans the light beam irradiated toward the eye to be examined. By providing scanning means and analyzing the detection signal obtained based on the principle of spectral interference, an anterior segment image of the eye to be examined can be obtained.

FIG. 4 is a diagram showing an example in which scanning means for scanning a light beam irradiated toward the eye to be examined is provided in the optical system of FIG. 1 as the second embodiment. Components having the same functions as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted.
In FIG. 4, reference numeral 60 denotes a galvano mirror serving as a scanning unit for scanning a light beam emitted toward the eye to be examined, and in a predetermined direction (in this embodiment, a direction in which the light beam is scanned in the vertical direction with respect to the eye to be examined). Can be rotated. The reflection surface of the galvanometer mirror 60 is disposed at the focal position of the objective lens 9 so that the rotation angle of the mirror is proportional to the incident height of the light beam to the anterior eye part and the optical path length does not change by driving. It has become. The configuration of the control system for driving and controlling the ophthalmologic measurement apparatus according to the second embodiment is the same as the block diagram of the control system shown in FIG. Will be omitted.

  Of the low-coherent light emitted from the light source 1 shown in FIG. 4, the light beam that has passed through the beam splitter 3 is condensed on the fundus of the eye E through the measurement light projecting optical system 100. Of the low-coherent light emitted from the light source 1, the light beam reflected by the beam splitter 3 is condensed on the cornea of the eye E through the reference light projecting optical system 300. The combined light of the reflected light from the fundus of the eye E and the reflected light from the intraocular phase object including corneal reflection is spectrally divided into frequency components by the grating mirror 300 of the interference signal detection optical system 400. The light is condensed on the light receiving element 33. Depth information of each phase object such as cornea and crystalline lens in the eye E can be obtained by performing Fourier transform on the detection signal output from the light receiving element 33 in the arithmetic processing unit. The light beam passing through the reference light projecting optical system 300 is scanned in a predetermined direction with respect to the eye E by the galvanometer mirror 60. For this reason, the detection signal output from the light receiving element 33 includes information on each reflected light from the intraocular phase object obtained by scanning the light beam. The arithmetic processing unit obtains a cross-sectional image of the anterior ocular segment of the eye to be inspected by scanning by accumulating and adding information in the depth direction of the phase object in the eye obtained by Fourier transforming the detection signal. be able to. The obtained anterior segment cross-sectional image is displayed on the monitor 51 as shown in FIG.

  In this way, by interfering with the reference light beam and the object light beam and performing analysis based on the principle of spectral interference, even if the position of the eye to be examined is slightly deviated from the apparatus, both the reference light beam and the object light beam are Since it changes to the same extent, it is resistant to misalignment and out of focus, and it is possible to obtain in-vivo dimensions and cross-sectional images of the eye to be examined.

It is the figure which showed the optical system of the ophthalmic measurement apparatus in this embodiment. It is the block diagram which showed the control system of the ophthalmologic measurement apparatus in this embodiment. It is the figure which showed the condensing state of the measurement light which permeate | transmitted the ring lens. It is the figure which showed the optical system of the ophthalmic measurement apparatus in 2nd Embodiment. It is the figure which showed the to-be-examined eye part image displayed on the monitor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light source 4 Condensing lens 7 Hall mirror 9 Objective lens 14 Collimator lens 16 Ring lens 17 Light receiving element 18 Stage 23 Prism 30 Grating mirror 31 Condensing lens 33 Light receiving element 50 Control part 51 Monitor 52 Calculation processing part

Claims (5)

In an ophthalmologic measurement apparatus that measures the refractive power and axial length of the eye to be examined in a non-contact manner, the measurement light irradiation optical system that irradiates the eye to be examined with light of a low coherent length, and the low light that is emitted toward the eye to be examined A light receiving optical system that receives reflected light from the fundus of the eye to be examined by coherent length light, a refractive power measuring unit that obtains the refractive power of the eye based on the light receiving state of the reflected light received by the light receiving optical system, and Reference light irradiation optical system using reference light as reflected light from the anterior segment of the eye to be examined obtained by irradiation with light of low coherent length, reference light obtained by the reference light irradiation optical system, and measurement light irradiation optics An interference optical system that synthesizes and interferes with the reflected light from the fundus of the eye to be inspected obtained by the system, spectrally separates the obtained interference light into frequency components, and receives light signals obtained by the interference optical system. Based on the subject's eye Ophthalmic measuring apparatus comprising: the in vivo size measuring means for measuring the dimensions, the. 2. The ophthalmologic measurement apparatus according to claim 1, wherein the interference optical system includes an optical path length varying unit that varies an optical path length of reference light or measurement light, a spectral unit that splits the synthesized light flux into the frequency component, and the spectral component. And an optical member for causing the light receiving element to receive each light beam dispersed by the means, and the in-vivo dimension measuring means analyzes the received light signal output from the light receiving element using Fourier transform; An ophthalmic measurement characterized in that the axial length of the eye to be examined is measured based on the amount of change of the optical path length varying means, and the in-vivo dimensions in the anterior segment of the eye to be examined are measured based on the analysis result. apparatus. The ophthalmic measurement apparatus according to claim 2, further comprising a refractive power correction unit that corrects the refractive power of the eye to be examined based on the refractive power of the eye to be examined obtained by the refractive power measurement unit. The ophthalmologic measurement apparatus according to any one of claims 1 to 3 includes a scanning unit that scans the eye to be inspected with the reference light irradiation optical system toward the eye to be inspected, and a light beam that has been scanned by the scanning unit. A received light signal obtained by the interference optical system that receives a combined light beam of the reference light and reflected light from the fundus of the eye to be examined is analyzed using Fourier transform, and a cross-sectional image of the eye to be examined is based on the analysis result An ophthalmologic measurement apparatus comprising: an image information processing means for obtaining the image information; and a display means for displaying the cross-sectional image obtained by the image information processing means. Measuring light irradiation optical system that irradiates measurement light toward the fundus of the eye to be examined, and refractive power measurement that receives the reflected light from the fundus of the eye to be examined and obtains the refractive power of the eye to be examined based on the light receiving state of the received reflected light Means, a refractive power correcting means for correcting the refractive power of the eye to be examined based on the refractive power of the eye to be examined obtained by the refractive power measuring means, and irradiating the eye to be examined with light having a low coherent length. By combining the reflected light from the fundus of the low coherent length light corrected by the correcting means on the fundus of the eye to be examined and the reflected light of the low coherent length reflected from the anterior eye part. Interferometric optical system for causing interference and condensing the obtained interference light on the light receiving surface of the light receiving element, and measuring the in-vivo dimensions of the eye to be examined based on the received light signal from the interference light collected on the light receiving surface of the light receiving element And in-vivo dimension measuring means. Ophthalmic measurement apparatus according to.