JP2006272005A - Ophthalmologic measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable high-accuracy refracted wave surface measurement, adjusting an image obtained by refracted wave surface measurement to an image more suitable for analysis. <P>SOLUTION: A first moving means for moving a condensing position so that a light flux from a first light source is condensed on the vicinity of the eyegrounds of a tested eye and a second moving means for optically moving a first converting part for condensing the light flux reflected from the eyegrounds of the tested eye and a first light receiving part receiving the light flux can be independently driven, and further driven by the operation of an operator. An operation part controls the projection side/light receiving side according to a first light receiving signal from the first light receiving part (S101 to S105). Subsequently, when an independent mode is selected (S106, S107), the projection side/light receiving side is controlled by automatic adjusting processing or manual adjusting processing (S109 to S113). Further, the operation part measures the eye characteristics according to the adjusted measurement condition (S115 to S123). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ophthalmologic measuring apparatus, and more particularly to an ophthalmic measuring apparatus having a refractive wavefront measuring function having a mechanism for independently adjusting an illumination optical system and a light receiving optical system.

  2. Description of the Related Art In recent years, optical instruments used for medical use have become widespread as optical characteristic measuring apparatuses that perform eye functions such as eye refraction and adjustment, and examination of the inside of an eyeball, particularly in ophthalmology. For example, there is an apparatus called a photorefractometer that obtains the refractive power and corneal shape of the eye to be examined. For example, Japanese Patent Application No. 2000-351796 describes an optical characteristic measurement device that displays measurement data (measurement results) obtained under a plurality of conditions, image data and / or numerical data corresponding to the measurement results. The conventional optical characteristic measuring apparatus illuminates the eye to be examined in alignment adjustment, and moves the apparatus main body up, down, left, and right so that the spot image that receives the light beam reflected by the cornea coincides with the optical axis. The optical characteristic measurement device acquires a Hartmann image and an anterior ocular segment image when the spot image coincides with the optical axis, and measures the eye characteristic by processing the acquired signal. In addition, the measurement results of these various tests are important, for example, under what measurement conditions the patient's eye to be examined is placed.

  However, a conventional ophthalmic apparatus having a refractive wavefront measurement function has a mechanism in which an illumination optical system and a light receiving optical system move in conjunction with each other. In some cases, it was not suitable for image analysis. For example, the eyeball optical characteristics may differ depending on the location of one eye due to a cause such as surgery, trauma, injury, injury, or illness. In such a case, the conventional automatic measurement sometimes fails to obtain the measurement result required by the doctor.

  In the present invention, in view of the above points, the operator can adjust the obtained image to an image more suitable for analysis by the operation of independently adjusting the illumination optical system and the light receiving optical system in the apparatus main body. An object of the present invention is to provide an ophthalmologic measuring apparatus capable of measuring a refractive wavefront with high accuracy.

According to the first solution of the present invention,
A first illumination optical system having a first light source that emits a light beam having a first wavelength, and illuminating the first illumination light beam from the first light source so as to be condensed near the fundus of the eye to be examined;
A first conversion member that converts a reflected light beam reflected from the fundus of the eye to be examined into at least 17 beams, and a first light receiving unit that receives a plurality of light beams converted by the first conversion member as a first light reception signal; A first light receiving optical system for guiding the reflected light flux to the first light receiving unit;
First moving means for moving the condensing position of the first illumination optical system;
Second moving means for optically moving the first light receiving section and the first conversion member;
A mode switching unit capable of switching between an interlocking mode for interlocking movement operations of the first moving means and the second moving means and an independent mode that can be controlled independently;
A calculation unit that performs Zernike analysis and obtains optical characteristics of the eye to be inspected based on the tilt angle of the light beam obtained by the first light receiving unit, and the first moving unit and / or the second moving unit includes: The condensing position of the illumination light beam and / or the condensing position of the light beam converted by the first conversion member can be adjusted according to the light receiving position and / or the light receiving level of the first light receiving signal in the first light receiving unit. An ophthalmic measurement device is provided.
According to the second solution of the present invention,
A first illumination optical system having a first light source that emits a light beam having a first wavelength, and illuminating the first illumination light beam from the first light source so as to be condensed near the fundus of the eye to be examined;
A first conversion member that converts a reflected light beam reflected from the fundus of the eye to be examined into at least 17 beams, and a first light receiving unit that receives a plurality of light beams converted by the first conversion member; A first light receiving optical system that leads to the first light receiving unit;
First moving means for moving the condensing position of the first illumination optical system;
Second moving means for optically moving the first light receiving section and the first conversion member;
The tilt angle data of the light beam obtained by the first light receiving unit under different conditions by the first moving means or the second moving means are combined, and Zernike analysis is performed based on the combined data to obtain the optical characteristics of the eye to be examined. An ophthalmologic measurement apparatus including a calculation unit is provided.

  According to the ophthalmologic measurement apparatus of the present invention, an eye that is difficult to measure can be adjusted to an image suitable for analysis by manual operation on the apparatus main body, and highly accurate refraction wavefront measurement can be performed.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1. Configuration of Ophthalmic Measuring Device FIG. 1 is a diagram showing a schematic optical system 100 of an ophthalmic measuring device according to the present invention.
The optical system 100 of the ophthalmologic measurement apparatus is an apparatus that measures, for example, the optical characteristics of the eye 60 to be examined, which is an object, and includes a first illumination optical system 10, a first light receiving optical system 20, and a second light receiving optical system. 30, a common optical system 40, an adjustment optical system 50, a second illumination optical system 70, a third illumination optical system 75, a first moving unit 110 and a second moving unit 120. For the eye 60 to be examined, a retina 61 and a cornea 62 are shown in the figure.

  The first illumination optical system 10 includes, for example, a first light source unit 11 for emitting a light beam having a first wavelength, and a condensing lens 12, and is covered by a light beam (first illumination light beam) from the first light source unit 11. This is for illuminating a minute region on the retina (fundus) 61 of the optometer 60 so that the illumination conditions can be set as appropriate. The first illumination optical system 10 can move the condensing position by the first moving means 110.

  Moreover, the 1st wavelength of the 1st illumination light beam emitted from the 1st light source part 11 is a wavelength (for example, 780 nm) of an infrared region as an example. The first light source unit 11 preferably has a large spatial coherence and a small temporal coherence. Here, the 1st light source part 11 is a super luminescence diode (SLD), for example, Comprising: It can obtain a point light source with high brightness | luminance. The first light source unit 11 is not limited to the SLD. For example, even with a laser having a large spatial coherence or temporal coherence, by inserting a rotating diffusion plate or the like and appropriately reducing the temporal coherence, Can be used. Furthermore, even an LED with small spatial coherence and temporal coherence can be used by inserting a pinhole or the like at the position of the light source in the optical path as long as the amount of light is sufficient.

  The first light receiving optical system 20 includes, for example, a collimating lens 21 and a conversion member that converts a part of a light beam (first light beam) reflected and returned from the retina 61 of the eye 60 to be converted into at least 17 beams. And a first light receiving unit 23 for receiving a plurality of beams converted by the Hartman plate 22, and for guiding the first light flux to the first light receiving unit 23. The first light receiving optical system 20 can be moved so that the beam converted by the Hartmann plate 22 is condensed on the first light receiving unit 23 by the second moving means 120. Here, the first light receiving unit 23 is a CCD with low lead-out noise. As the CCD, for example, a general low noise type, a cooling CCD of 1000 × 1000 elements for measurement, etc. An appropriate type can be applied. The signal (first received light signal) received by the first light receiving unit 23 is used, for example, for obtaining eyeball wavefront aberration.

  The first moving unit 110 moves the first illumination optical system, and is driven by, for example, a motor. The condensing position of the first illumination light beam from the first illumination optical system can be adjusted by moving the first illumination optical system by the first moving unit 110.

  The second moving unit 120 moves the first light receiving optical system, and is driven by, for example, a motor. By moving the first light receiving optical system by the second moving means 120, the beam converted by the Hartmann plate 22 can be adjusted so as to be condensed on the first light receiving unit 23. In addition, as a moving means of the 1st moving means 110 and the 2nd moving means 120, a suitable apparatus and method can be used. Further, in the present embodiment, the first moving means 110 and the second moving means 120 can be independently driven in addition to being driven in conjunction with each other. Further, in addition to automatically performing measurement by these moving means, the first moving means 110 and the second moving means 120 can be driven by an operator's operation (manual operation).

  The second illumination optical system 70 includes a second light source 72 for emitting a light beam having a second wavelength, and a platide ring 71. Note that the second light source 72 may be omitted. In FIG. 2, an example of the block diagram of the placido ring 71 is shown. The Placido ring (PLACIDO'S DISC) 71 is for projecting a pattern index composed of a plurality of concentric annular zones as shown in FIG. Note that the index of a pattern composed of a plurality of concentric annular zones is an example of an index of a predetermined pattern, and other appropriate patterns can be used. And after the alignment adjustment mentioned later is completed, the parameter | index of the pattern which consists of a some concentric ring zone can be projected.

The third illumination optical system 75 mainly performs, for example, alignment adjustment described later, and includes a third light source unit 31 for emitting a light beam having a third wavelength, a condensing lens 32, and a beam splitter 33. .
The second light receiving optical system 30 includes a condenser lens 34 and a second light receiving unit 35. The second light receiving optical system 30 is a light beam (second light beam) that the pattern of the placido ring 71 illuminated from the second illumination optical system 70 reflects and returns from the anterior eye portion or the cornea 62 of the eye 60 to be examined. The light is guided to the second light receiving unit 35. Further, a light beam (third light beam) emitted from the third light source unit 31, reflected from the cornea 62 of the eye 60 to be examined, and returned can be guided to the second light receiving unit 35. The second wavelength and the third wavelength of the light beams emitted from the second light source 72 and the third light source unit 31 are different from the first wavelength (here, 780 nm), for example, and a long wavelength can be selected (for example, 940 nm). ). The signal received by the second light receiving unit 35 is used, for example, to obtain alignment adjustment and corneal wavefront aberration.

  The common optical system 40 is disposed on the optical axis of the light beam emitted from the first illumination optical system 10, and includes the first and second illumination optical systems 10 and 70, the first and second light receiving optical systems 20 and 30, and the third. For example, the illumination optical system 75 may include the afocal lens 42, beam splitters 43 and 45, and a condenser lens 44. The beam splitter 43 transmits (reflects) the wavelength of the third light source unit 31 to the eye 60 to be examined, reflects the second light beam and the third light beam that are reflected back from the cornea 62 of the eye 60 to be examined, On the other hand, it is formed of a mirror (for example, a dichroic mirror) that transmits the wavelength of the first light source unit 11. The beam splitter 45 transmits (reflects) the wavelength of the first light source unit 11 to the eye 60 to be examined, and transmits a first light beam reflected and returned from the retina 61 of the eye 60 to be examined (for example, (Polarization beam splitter). The beam splitters 43 and 45 prevent the first, second and third light beams from entering the other optical system and causing noise.

  The adjustment optical system 50 mainly adjusts the working distance, for example, and includes a fourth light source unit 51, a fifth light source unit 55, condensing lenses 52 and 53, and a third light receiving unit 54. . The working distance adjustment is performed by, for example, irradiating a parallel light beam near the optical axis emitted from the fifth light source unit 55 toward the eye 60 and reflecting the light reflected from the eye 60 with the condenser lens 52. , 53 is received by the third light receiving unit 54. Further, when the eye 60 to be examined is at an appropriate working distance, a spot image from the fifth light source unit 55 is formed on the optical axis of the third light receiving unit 54. On the other hand, when the subject eye 60 deviates back and forth from an appropriate working distance, the spot image from the fifth light source unit 55 is formed above or below the optical axis of the third light receiving unit 54. The third light receiving unit 54 only needs to be able to detect a change in the position of the light beam in the plane including the fifth light source unit 55, the optical axis, and the third light receiving unit 54. A CCD, a position sensing device (PSD), etc. can be applied.

Next, alignment adjustment will be described. The alignment adjustment is mainly performed by the second light receiving optical system 30 and the third illumination optical system 75.
First, the light beam from the third light source unit 31 illuminates the eye 60 to be inspected with a parallel light beam via the condenser lens 32, the beam splitters 33 and 43, and the afocal lens 42. The reflected light beam reflected by the cornea 62 of the eye 60 to be examined is emitted as a divergent light beam as if it was emitted from a point having a half radius of curvature of the cornea 62. The divergent light beam is received as a spot image by the second light receiving unit 35 through the afocal lens 42, the beam splitters 43 and 33, and the condenser lens 34.

  Here, when the spot image on the second light receiving unit 35 is off the optical axis, the eye optical characteristic measuring device main body is moved and adjusted vertically and horizontally so that the spot image coincides with the optical axis. As described above, when the spot image coincides with the optical axis, the alignment adjustment is completed. In the alignment adjustment, the cornea 62 of the eye 60 to be examined is illuminated by the fourth light source unit 51, and an image of the eye 60 to be obtained obtained by this illumination is formed on the second light receiving unit 35. Then, the pupil center may coincide with the optical axis.

Next, the positional relationship between the first illumination optical system 10 and the first light receiving optical system 20 will be schematically described.
A beam splitter 45 is inserted into the first light receiving optical system 20, and light from the first illumination optical system 10 is transmitted to the eye 60 to be examined by the beam splitter 45 and also from the eye 60 to be examined. The reflected light is transmitted. The first light receiving unit 23 included in the first light receiving optical system 20 receives light that has passed through the Hartmann plate 22 that is a conversion member, and generates a light reception signal.

  Further, the first light source unit 11 and the retina 61 of the eye 60 to be examined form a conjugate relationship. The retina 61 of the eye 60 to be examined and the first light receiving unit 23 are conjugate. The Hartmann plate 22 and the pupil of the eye 60 to be examined form a conjugate relationship. Further, in the first light receiving optical system 20, the pupil and the Hartmann plate 22 form a substantially conjugate relationship. That is, the front focal point of the afocal lens 42 substantially coincides with the pupil.

  The lens 12 converts the diffused light from the light source 11 into parallel light. The stop 14 is in an optically conjugate position with the pupil of the eye and the Hartmann plate 21. The diaphragm 14 has a diameter smaller than the effective range of the Hartmann plate 21 so that so-called single-pass aberration measurement (a method in which the eye aberration affects only the light receiving side) is established. In order to satisfy the above, the lens 13 is disposed so that the fundus conjugate point of the actual light ray is at the front focal position, and further, the rear focal position is coincident with the stop 14 in order to satisfy the conjugate relationship with the eye pupil. ing.

  The light beam 15 travels in the same manner as the light beam 24 in a paraxial manner after the light beam 24 and the beam splitter 45 have a common optical path. However, in the single pass measurement, the diameters of the respective light beams are different, and the beam diameter of the light beam 15 is set to be considerably smaller than that of the light beam 24. Specifically, the beam diameter of the light beam 15 may be, for example, about 1 mm at the pupil position of the eye, and the beam diameter of the light beam 24 may be about 7 mm (in the drawing, from the beam splitter 45 of the light beam 15 to the fundus). 61 is omitted).

Next, the Hartmann plate 22 as a conversion member will be described.
The Hartmann plate 22 included in the first light receiving optical system 20 is a wavefront conversion member that converts a reflected light beam into a plurality of beams. Here, a plurality of micro Fresnel lenses arranged in a plane orthogonal to the optical axis is applied to the Hartmann plate 22. Further, in general, in order to measure the spherical component, third-order astigmatism, and other higher-order aberrations of the subject eye 60 with respect to the measurement target portion (the subject eye 60), at least 17 through the subject eye 60 are measured. It is necessary to measure with a beam.

  The micro Fresnel lens is an optical element, and includes, for example, an annular zone having a height pitch for each wavelength and a blaze optimized for emission parallel to the focal point. The micro Fresnel lens here is, for example, an optical path length difference of 8 levels applying a semiconductor microfabrication technique, and achieves a high light collection rate (for example, 98%).

Further, the reflected light from the retina 61 of the eye 60 passes through the afocal lens 42 and the collimating lens 21 and is condensed on the first light receiving unit 23 via the Hartmann plate 22. Therefore, the Hartmann plate 22 includes a wavefront conversion member that converts the reflected light beam into at least 17 beams.
FIG. 3 is a block diagram showing a schematic electrical system 200 of the eye optical property measuring apparatus according to the present invention. The electrical system 200 related to the ophthalmologic measurement apparatus includes, for example, a calculation unit 210, a control unit 220, a display unit 230, a memory 240, a first drive unit 250, a second drive unit 260, and an input unit 270.

  The calculation unit 210 inputs the light reception signal (4) obtained from the first light receiving unit 23, the light reception signal (7) obtained from the second light receiving unit 35, and the light reception signal (10) obtained from the third light receiving unit 54, Calculate total wavefront aberration, Zernike coefficient, etc. Further, the arithmetic unit 210 inputs input signals such as desired settings, instructions, and data from the input unit 270. Further, the calculation unit 210 sets the central intensity of white light MTF (Modulation Transfer Function), which is an index representing the transmission characteristics of corneal wavefront aberration, aberration coefficient, and spatial frequency, and the point image intensity distribution PSF (Point Spread Function). The Strehl ratio obtained by dividing by the central intensity of the PSF obtained in the case of the aberration optical system, the pattern of the Landolt ring having a size corresponding to an appropriate visual acuity in order to examine the visual acuity of the patient, and the like are calculated. In addition, signals according to such calculation results are output to the control unit 220 that controls the entire electric drive system, the display unit 230, and the memory 240, respectively.

  The control unit 220 controls turning on and off of the first light source unit 11 based on a control signal from the calculation unit 210, and controls the first driving unit 250 and the second driving unit 260. Based on the signal according to the calculation result in the calculation unit 210, the signal (1) is output to the first light source unit 11, the signal (5) is output to the placido ring 71, and the third light source unit 31 is output. Signal (6) is output to the fourth light source unit 51, the signal (8) is output to the fifth light source unit 55, and the signal (9) is output to the fifth light source unit 55. And outputs a signal to the second driving unit 260.

For example, the first drive unit 250 is configured to input the first illumination optical system 10 based on the light reception signal (4) from the first light receiving unit 23 input to the calculation unit 210 or the movement signal input from the input unit 270. The whole is moved in the optical axis direction to move the condensing position, and the signal (2) is output to the first moving means 110 and the moving means is driven. Thereby, the first drive unit 250 can move and adjust the first illumination optical system 10.
For example, the second drive unit 260 is based on the light reception signal (4) from the first light receiving unit 23 input to the calculation unit 210 or the input signal input from the input unit 270. The whole is moved in the optical axis direction, and a signal (3) is output to the second moving means 120 and the moving means is driven. Thereby, the second drive unit 260 can move and adjust the first light receiving optical system 20.

  The input unit 270 includes switches, buttons, a keyboard, a pointing device, and the like for inputting various input signals such as desired settings, instructions, and data. For example, the input unit 270 includes a mode switch 271, an operation switch, a measurement start button, and a movement switch that moves the first illumination optical system 10 or the first light receiving optical system 20 in the + direction and the − direction. The mode changeover switch 271 is a switch for switching between an interlocking mode in which the first illumination optical system 10 and the first light receiving optical system 20 are moved in conjunction with each other and an independent mode in which the movement is performed independently. The operation changeover switch is a switch for switching between measurement by automatic adjustment and measurement by manual adjustment. The movement switch includes, for example, a projection-side movement switch that moves the first illumination optical system 10 and a light-receiving side movement switch that moves the first light-receiving optical system 20. The operator operates the movement switch when selecting manual adjustment, and controls the first moving unit 110 and the second movement via the first driving unit 250 and the second driving unit 260 under the control of the calculation unit 210 and the control unit 220. The means 120 can be driven to move the first illumination optical system 10 and the first light receiving optical system 20 independently in the + direction and the − direction. Note that the diopter value is changed by a setting step (for example, 0.25 diopter) with respect to one input of the movement switch, and the first illumination optical system 10 and the first light receiving optical system 20 are moved in the designated direction. May be. Further, the operator may designate the diopter values on the first illumination optical system side and the first light receiving optical system side with a keyboard. In this case, the first moving unit 110 and the second moving unit 120 are driven via the first drive unit 250 and the second drive unit 260 under the control of the calculation unit 210 and the control unit 220, and the first illumination optical system 10 and The first light receiving optical system 20 moves to a position corresponding to the designated diopter value. It should be noted that these diopter value designation methods and input means can be used as appropriate.

Next, Zernike analysis will be described. A generally known method of calculating Zernike coefficients C _n ^m from Zernike polynomials will be described. Zernike coefficients C _n ^m is, for example, are important parameters for grasping the optical characteristic of the eye 60 on the basis of inclination angles of the light fluxes obtained by the first light receiving portion 23 through the Hartmann plate 22.
The wavefront aberration W (X, Y) of the eye 60 to be examined is expressed by the following equation using the Zernike coefficient C _i ^2j−i and the Zernike polynomial Z _i ^2j−i .

However, (X, Y) are the vertical and horizontal coordinates of the Hartmann plate 22. In the above equation, n is the analysis order.
The wavefront aberration W (X, Y) is received by the first light receiving unit 23 with the vertical and horizontal coordinates of the first light receiving unit 23 being (x, y), the distance between the Hartmann plate 22 and the first light receiving unit 23 being f. If the moving distance of the point image is (Δx, Δy), the following relationship is established.

Here, the Zernike polynomial Z _n ^m is expressed by the following Expression 3, and specifically, shown in FIGS. However, n and m correspond to i, 2j-i in FIGS.

Incidentally, the Zernike coefficients C _n ^m can obtain specific values by minimizing the squared error expressed by Equation 4 below.

However, W (X, Y): Wavefront aberration, (X, Y): Hartmann plate coordinates, (Δx, Δy): Movement distance of the point image received by the first light receiving unit 23, f: Hartmann plate 22 And the first light receiving unit 23.
Calculation unit 210 calculates the Zernike coefficients C _n ^m, obtaining spherical aberration, coma aberration, the eye's optical characteristics such as astigmatism by using this.

2. Next, the influence on the Hartmann image when the diopter values of the first illumination optical system 10 (projection side) and the first light reception optical system 20 (light reception side) are deviated. Will be described.

  FIG. 4 is a diagram of a Hartmann image when there is no positional deviation on the projection side and the light receiving side. A Hartmann image when the light beam emitted from the first illumination optical system 10 is reflected by the fundus 61 of the eye 60 to be examined and condensed on the first light receiving unit 23, that is, when there is no positional deviation on the projection side and the light reception side. is there.

  FIG. 5 is an explanatory diagram of the influence on the Hartmann image due to the positional deviation between the projection side and the light receiving side. The Hartmann image shown in FIGS. 6 and 7 will be described below with reference to FIG.

  FIG. 6 is a diagram of a Hartmann image when a positional deviation on the projection side occurs. FIG. 6A shows a Hartmann image when only the projection side is deviated by +5 diopter (+ 5D) from the state of FIG. When the projection side is deviated in the + direction, as shown by the broken line in FIG. 5A, the light beam emitted from the first illumination optical system 10 is incident from the outside of the central axis to the inside, and therefore the fundus of the eye 60 to be examined. Condensed in front of 61. Since the fundus 61 reflects the light beam that is not condensed, when the reflected light beam is received by the first light receiving unit 23, the point image of the light reception signal is blurred and the light reception level (light amount) of the light reception signal is reduced.

  On the other hand, FIG. 6B shows a Hartmann image when only the projection side is deviated by −5 diopter (−5D) from the state of FIG. When the projection side is deviated in the-direction, as indicated by the solid line in FIG. 5A, the light beam emitted from the first illumination optical system 10 is incident from the inner side to the outer side of the central axis. It becomes a light beam that is condensed behind the light. As in the case where the projection side is deviated in the + direction, since the light beam that is not condensed is reflected on the fundus 61, when the reflected light beam is received by the first light receiving unit 23, the point image of the light reception signal is blurred, The light reception level becomes small.

  Thus, the projection side relates to the light reception level of the point image of the light reception signal received by the first light receiving unit 23. That is, the point image can be blurred or sharpened by moving the projection side. In order to increase the light reception level, the projection side is moved to the direction in which the light reception level increases in the + direction or the − direction. In the automatic adjustment, the calculation unit 210 adjusts the diopter value on the projection side by moving the first illumination optical system 10 so as to increase the light reception level of the point image based on the light reception signal of the first light reception unit 23. ing.

  FIG. 7 is a diagram of a Hartmann image when a positional deviation on the projection side occurs. FIG. 7A shows a Hartmann image when only the light receiving side is deviated by + 5D from the state of FIG. When the light receiving side is shifted in the + direction, the light beam reflected by the fundus 61 is not perpendicular to the Hartmann plate 22 but enters the inner direction from the outside of the central axis, as shown by the broken line in FIG. The light is condensed from the axis and reaches the first light receiving unit. The point images received by the first light receiving unit 23 are gathered as a whole from the central axis, and become an image having a small point image interval as shown in FIG.

  On the other hand, FIG. 7B shows a Hartmann image when only the light receiving side is shifted by −5D from the state of FIG. When the light receiving side is shifted in the-direction, as shown by the solid line in FIG. 5B, the light beam reflected by the fundus 61 is not perpendicular to the Hartmann plate 22, but enters from the inner side to the outer side of the central axis. Focus away from the axis. The point image received by the first light receiving unit 23 as a whole is separated from the central axis and becomes an image having a large point image interval as shown in FIG. 7B.

  Thus, the light receiving side relates to the point image interval of the point image of the light receiving signal received by the first light receiving unit 23. That is, when the point image interval is small, the light receiving side can be corrected to an appropriate diopter value by moving the light receiving side in the-direction, and when the point image interval is large, the light receiving side can be moved in the + direction. In the automatic adjustment, the calculation unit 210 adjusts the diopter value on the light receiving side by moving the first light receiving optical system side so that the point image interval becomes a predetermined interval based on the light reception signal of the first light receiving unit 23. ing.

  FIG. 8 is a diagram of a Hartmann image of an eye having optical characteristics that are not uniform due to the influence of surgery, illness, wound, injury, and the like. The Hartmann image shown in FIG. 8 is an example of an eyeball having different optical characteristics in the upper half and the lower half. In this example, since the diopter value is adjusted only by the upper half, the lower half is measured in a state where the point image interval is narrow, that is, the light receiving side is shifted. For such an eye, since the interval between point images in the lower half is narrow, measurement may be difficult with a conventional ophthalmic measurement apparatus, and fine adjustment is required. In this embodiment, the Hartmann image can be corrected and fine measurement can be performed by finely adjusting the diopter value by manual operation for such an eye. For example, as in the Hartmann image in Fig. 8, the upper half can measure the optical characteristics appropriately, but the lower half moves the light receiving side in the-direction when the point image interval is narrow and appropriate measurement is impossible. By doing so, the point image interval can be widened. Thus, although the upper half point image interval is widened, a Hartmann image suitable for analysis as a whole can be detected, and the optical characteristics can be obtained by the calculation unit 210. If the lower half is blurred and appropriate measurement is not possible, shift the projection side in the + or-direction to sharpen the point image, and make appropriate measurements for both the upper and lower halves. It can be in a possible state.

3. Operation Mode In the present embodiment, the interlock mode in which the first illumination optical system 10 and the first light receiving optical system 20 move in conjunction with each other, and the first illumination optical system 10 and the first light receiving optical system 20 move independently. And an independent mode that can be switched by the mode changeover switch 271 of the input unit 270. Further, in the independent mode, the first illumination optical system 10 and the first light receiving optical system 20 can be selected to be automatically adjusted separately or manually adjusted by the operator.

  In the interlock mode, the first illumination optical system 10 and the first light receiving optical system 20 assume that the light beam from the first light source unit 11 is reflected at the point where the light is collected, and the signal by the reflected light from the first light receiving unit 23. Move in conjunction so that the level is maximum. Specifically, the first illumination optical system 10 and the first light receiving optical system 20 move in a direction in which the signal level at the first light receiving unit 23 increases, and stop at a position where the signal level becomes maximum. Thereby, the light beam from the first light source unit 11 is collected on the eye 60 to be examined. In addition to the signal level, the first illumination optical system 10 and the first light receiving optical system 20 may be moved by an appropriate index.

  In the automatic adjustment in the independent mode, the first illumination optical system 10 and the first light receiving optical system 20 move independently. The calculation unit 210 obtains the interval between the point images based on the first received light signal from the first light receiving unit 23, and if there is an area narrower than the predetermined interval range in the point image interval, the calculation unit 210 moves the predetermined interval range to the minus side. When there is a wider area, the first light receiving unit 23 is moved to the plus side by the second moving unit 120. In addition, the calculation unit 210 moves the first illumination optical system 10 by the first moving unit 110 so that the signal level of the first light reception signal in the first light reception unit 23 is within a predetermined level range or maximum. The predetermined interval range and the predetermined level range may be set in advance and stored in the memory 240 or the like. Further, these ranges may be appropriately changed by the input unit 270.

  In the manual adjustment in the independent mode, the first illumination optical system 10 and the first light receiving optical system 20 can be moved to arbitrary diopter positions by the projection side and light receiving side moving switches. When the independent mode is selected, the manual wavefront measurement mode is set by the operation switch. In the manual wavefront measurement mode, for example, the reflex and kerato measurements are performed in the interlock mode, and after the measurement is completed, the manual adjustment state is entered.

  FIG. 9 is a display diagram in a manual adjustment state. At this time, the calculation unit 210 displays the diopter values for manual wavefront measurement (S1: projection side, S2: light receiving side) on the display unit 230. As the initial value of the diopter value to be displayed, a diopter value obtained by performing reflex and kerato measurement in the interlock mode may be used. In addition to the diopter value, the astigmatism power C, the astigmatism axis A, and other appropriate parameters may be further displayed. Further, the calculation unit 210 takes in the first light receiving signal for the Hartmann image from the first light receiving unit 23 and displays the Hartman image on the display unit 230. The calculation unit 210 may fetch the first received light signal from the first light receiving unit 23 and update the display of the Hartmann image every predetermined period or whenever the diopter value is changed by manual operation. .

  The operator can move the projection side and the light receiving side to arbitrary diopter positions with the input unit 270 such as a projection side and light receiving side movement switch or a keyboard in the manual adjustment state. The projection side moves in the + direction by the projection side + movement switch, and moves in the-direction by the projection side-movement switch. The point image can be blurred or sharpened by movement on the projection side. Similarly, the light receiving side moves in the + direction by the light receiving side + movement switch, and moves in the-direction by the light receiving side-movement switch. The point image interval can be increased or decreased by moving the light receiving side. When the switch input is performed, the arithmetic unit 210 changes the diopter value in the + or − direction by a preset step (for example, 0.25 diopter) for one switch input. The calculation unit 210 changes the diopter values S1 and S2 displayed on the display unit 230. In addition, the calculation unit 210 moves the first illumination optical system 10 and the first light receiving optical system 20 via the first drive unit 250 and the second drive unit 260 according to the changed diopter value. After setting the diopter value, the wavefront measurement is started by pressing the measurement start switch.

  Further, the operator may specify the diopter value by using a keyboard of the input unit 270 or the like. When the diopter value is input from the input unit 270, the calculation unit 210 changes the diopter values S1 and S2 displayed on the display unit 230, and passes through the control unit 220, the first drive unit 250, and the second drive unit 260. The first moving unit 110 and the second moving unit 120 perform control to automatically move the first illumination optical system 10 and the first light receiving optical system 20 to positions corresponding to the input diopter values.

4). Flowchart FIGS. 10 to 12 are flowcharts showing the operation of an ophthalmologic measurement apparatus having a wavefront measurement function having an optical system independent adjustment mechanism.
First, when the interlocking mode is set as the preset, the calculation unit 210 selects the interlocking mode in which the first illumination optical system 10 and the first light receiving unit 23 are interlockedly moved, and performs alignment adjustment (S101). Further, the calculation unit 210 may display a menu for selecting the interlock mode or the independent mode on the display unit 230 and input a mode selection signal from the mode changeover switch 271 of the input unit 270. In this case, after adjusting the alignment, the calculation unit 210 proceeds to the process of step S103 when the interlocking mode is selected, and proceeds to the process of step S109 when the independent mode is selected.

  The calculation unit 210 takes in the first light receiving signal for the Hartmann image using the first light receiving unit 23 such as a low noise CCD (S102). The arithmetic part 210 calculates the average of the received light signal level for the input first received light signal. Further, the calculation unit 210 reads a predetermined signal level from the memory 240 and determines whether the average of the received light signal level is the predetermined signal level (S103). The predetermined signal level is set in advance and stored in the memory 240. When the average received light signal level is the predetermined signal level, the arithmetic part 210 proceeds to the process of step S106. In step S103, an appropriate value such as a minimum value, a maximum value, or a total may be used in addition to the average of the received light signal level. Further, after step S101, the arithmetic unit 210 inputs a diopter value measured by a refractometer incorporated in the apparatus or a diopter value measured by another refractometer, and the first moving means 110 and You may move the 1st illumination optical system 10 and the 1st light-receiving part 23 by the 2nd moving means 120 to the position corresponding to the inputted diopter value.

  When the average received light signal level is not a predetermined signal level, the calculation unit 210 sends the first illumination optical system 10 and the first driving unit 250 and the second driving unit 260 to the first driving unit 250 and the second driving unit 260 automatically or in accordance with an instruction from the input unit 270. A movement signal for moving the light receiving unit 23 is output, and the process returns to step S102 (S105). The first driving unit 250 and the second driving unit 260 receive the movement signal from the calculation unit 210, and the first moving optical system 10 and the first driving unit 120 are operated by the first moving unit 110 and the second moving unit 120 according to the input signal. The light receiving unit 23 is moved in conjunction.

  Next, when the average received light signal level is a predetermined signal level, the calculation unit 210 displays a menu on the display unit 230 for instructing whether to select the independent mode or the automatic mode. A mode selection signal is input from the mode changeover switch 271 (S106). This selection can be automatically determined based on, for example, the number of point images (points) at which the light reception level reaches a predetermined signal level. The calculation unit 210 determines whether the input mode selection signal indicates selection of the independent mode (S107). Note that an appropriate method can be used for inputting the mode selection signal other than the input by the switch. When the independent mode is selected, the calculation unit 210 proceeds to the process of step S109, and when the independent mode is not selected, the calculation unit 210 proceeds to the process of step S115. Moreover, you may transfer to the predetermined mode by time-up.

  Further, the arithmetic unit 210 displays a menu for instructing whether the adjustment on the projection side and the light receiving side is automatic adjustment or manual adjustment on the display unit 230, and inputs an operation selection signal from the operation changeover switch of the input unit 270. . The calculation unit 210 determines whether the input operation selection signal is automatic adjustment or manual adjustment (S109). Note that an appropriate method can be used for inputting the operation selection signal other than the input by the switch.

  When determining that the automatic adjustment is performed (S109), the calculation unit 210 performs an independent mode automatic adjustment process (S111). In the independent mode automatic adjustment processing, the first light receiving unit 23 is moved according to the point image interval of the first light receiving signal taken from the first light receiving unit 23, and the first illumination optical system 10 is moved according to the point image level. By moving the first light receiving unit 23 and the first illumination optical system 10 independently, measurement suitable for the eyeball can be performed.

  FIG. 11 is a flowchart of the independent mode automatic adjustment processing. The independent mode automatic adjustment process in step S111 will be described below.

  First, the calculation unit 210 reads the first light reception signal from the first light reception unit 23, detects the interval between the point images based on the captured first light reception signal, and obtains the average of the point image intervals (S201). The calculation unit 210 reads a predetermined interval set in advance from the memory 240 and compares it with the average point image interval detected from the first light reception signal. When the average point image interval is smaller than the predetermined interval set in advance (S203), the calculation unit 210 outputs a signal for moving the first light receiving unit 23 in the-direction to the second driving unit 260, and step The process returns to S201 (S205). When the average point image interval is larger than the predetermined interval (S207), the arithmetic unit 210 outputs a signal for moving the first light receiving unit 23 in the + direction to the second driving unit 260, and performs the process of step S201. Return (S209). The second drive unit 260 receives a signal from the calculation unit 210 and drives the second moving unit 120 according to the input signal. In addition, when the average point image interval is a predetermined interval, the arithmetic unit 210 proceeds to the process of step S211. In addition, the comparison between the point image interval and the predetermined interval may use an appropriate value such as a minimum value, a maximum value, or a total in addition to the average of the point image intervals detected in step S201. Further, the calculating unit 210 uses the second moving means to move the first conversion member to the minus side when there is an area where the point image interval is narrower than the predetermined interval range, and to the plus side when there is an area wider than the predetermined interval range. It is also possible to adjust the point image interval within a predetermined interval range by moving the condensing position of the light beam converted in (1).

  Next, the calculation unit 210 reads the first light reception signal from the first light reception unit 23, detects individual point image levels based on the read first light reception signal, and obtains the average of the point image levels (S211). The calculation unit 210 determines whether the average point image level is higher than the predetermined level read from the memory 240 (S213). In addition, the comparison between the point image level and the predetermined level may use an appropriate value such as a minimum value, a maximum value, or a total in addition to the average of the individual point image levels detected in step S211. When the average point image level is lower than the predetermined level, the calculation unit 210 outputs a signal for moving the first illumination optical system 10 to the first drive unit 250, and returns to the process of step S211 (S215). The moving direction of the first illumination optical system 10 may be moved in an arbitrary direction to determine whether the point image level increases, and may be moved in the direction in which the point image level increases. The first drive unit 250 receives a signal from the calculation unit 210 and moves the first illumination optical system 10 by the first moving unit 110 in accordance with the input signal. If the average point image level is higher than the predetermined level (S213), the calculation unit 210 ends the independent mode automatic adjustment process, and proceeds to the process of step S115.

  On the other hand, returning to the flowchart of FIG. 10, when determining that manual adjustment is made (S <b> 109), the arithmetic unit 210 performs independent mode manual adjustment processing (S <b> 113). In the independent mode manual adjustment process, the calculation unit 210 inputs the operation of the input unit 270 by the operator and moves the first illumination optical system 10 (projection side) and the first light receiving optical system 20 (light receiving side) independently. Measurement that can be fine-tuned. The operator sets the diopter values on the projection side and the light receiving side using the input unit 270, and the first illumination optical system 10 and the first light receiving optical system 20 are moved according to the set diopter values.

FIG. 12 is a flowchart of the independent mode manual adjustment process. The independent mode manual adjustment process in step S113 will be described below.
First, the calculation unit 210 displays the diopter value adjusted in the interlock mode in step S105 on the display unit 230 (S301). In addition, the calculation unit 210 takes in the first light reception signal for the Hartmann image from the first light reception unit 23 and displays the Hartman image on the display unit 230. The calculation unit 210 may capture the first light reception signal from the first light reception unit 23 and update the display of the Hartmann image at predetermined intervals. Note that the display of the Hartmann image can be updated at an appropriate timing, such as when the diopter value is changed by a manual operation, in addition to being performed every cycle.

Next, the calculation unit 210 inputs a projection-side diopter value designation signal from the input unit 270 such as a projection-side movement switch or a keyboard (S303). If the diopter value designation signal is not input or is not designated, the calculation unit 210 proceeds to step S306. When inputting from the projection-side movement switch, the calculation unit 210 may change only a diopter value corresponding to a preset step for one switch input. When inputting from the keyboard, the arithmetic unit 210 sets the input value as a diopter value. The calculation unit 210 displays the designated projection-side diopter value on the display unit 230, and further outputs a drive command for the first moving unit 110 to the first drive unit 250 based on the projection-side diopter value (S305). Further, the first drive unit 250 receives a drive command from the calculation unit 210, drives the first moving unit 110 according to the drive command, and moves the first illumination optical system 10. The calculation unit 210 determines whether or not the adjustment of the projection-side diopter value has been completed. If not completed, the calculation unit 210 returns to step S303, and if completed, the process proceeds to step S307 (S306). For example, a determination completion signal may be input from the input unit 270.
Next, the calculation unit 210 inputs a light-receiving-side diopter value designation signal from the input unit 270 such as a light-receiving-side movement switch or a keyboard (S307). If the diopter value designation signal is not input or is not designated, the calculation unit 210 proceeds to step S310. The designation of the diopter value by the light receiving side movement switch and the keyboard can be the same as in the case of the projection side described above. The calculation unit 210 displays the designated light receiving side diopter value on the display unit 230, and further outputs a driving command for the second moving means 120 to the second driving unit 260 based on the light receiving side diopter value (S309). In addition, the second drive unit 260 receives a drive command from the calculation unit 210, drives the second moving unit 120 according to the drive command, and moves the first light receiving optical system 20. By allowing the projection side and the light receiving side to move independently independently, an image suitable for analysis can be obtained for an eyeball that is difficult to measure in the interlock mode. The calculation unit 210 determines whether the adjustment of the light receiving side diopter value has been completed. If it has not been completed, the calculation unit 210 returns to step S307, and if it has been completed, the process proceeds to step S311 (S310). For example, a determination completion signal may be input from the input unit 270.

  The calculation unit 210 determines whether to start measurement using the designated diopter value (S311). For example, the measurement start may be determined by displaying on the display unit 230 a display instructing whether or not to start the measurement, and inputting a measurement start signal from the measurement start button of the input unit 270. If the calculation unit 210 determines that the measurement has started, the calculation unit 210 ends the independent mode manual adjustment process and proceeds to the process of step 115. If the calculation unit 210 determines not to start the measurement, the calculation unit 210 returns to the process of step S303 and sets the diopter value again. Further, the mode changeover switch 271 or the operation changeover switch of the input unit 270 may be used to shift to automatic adjustment in the interlock mode or the independent mode at an appropriate timing.

  Returning to the flowchart of FIG. 10, the calculation unit 210 performs signal detection under the measurement conditions adjusted in the interlocking mode or the independent mode (S115). The calculation unit 210 takes in the first light receiving signal for the Hartmann image using the first light receiving unit 23 such as a low noise CCD.

  In addition, the calculation unit 210 performs Zernike analysis based on the captured first received light signal and calculates a Zernike coefficient (S117). Next, the calculation unit 210 performs an optical characteristic calculation process based on the first light reception signal (S119). Here, the optical characteristics are appropriate eye characteristics such as aberration and eye refractive power. The calculation unit 210 calculates the optical characteristics of the first received light signal based on the measurement principle of the Hartmann wavefront sensor. What is obtained by the first light reception signal is the wavefront aberration (eyeball wavefront aberration) of the eyeball optical system. Further, the calculation unit 210 displays the measured optical characteristics such as the Hartmann image and the eyeball wavefront aberration on the display unit 230 (S121).

In addition, in place of or in parallel with steps S115 to S121, the calculation unit 210 captures the second received light signal for the anterior segment image by the second light receiving unit 35, wavefront aberration (corneal wavefront aberration) generated in the cornea, cornea You may calculate optical characteristics, such as a shape. After capturing the second received light signal, the arithmetic unit 210 analyzes the position of the ring image that is substantially concentric with the bright spot of the corneal apex reflection using an image processing technique. For example, about 256 positions of the ring are acquired over 360 degrees on the circumference. In addition, the calculation unit 210 calculates the inclination of the cornea from the position of the ring. In addition, the calculation unit 210 calculates the optical characteristics by calculating the height of the cornea from the inclination of the cornea and treating the cornea in the same manner as the optical lens. What is obtained by the second light receiving signal is wavefront aberration (corneal wavefront aberration) generated in the cornea. The calculation unit 210 displays the calculated corneal wavefront aberration, corneal shape, and the like on the display unit 230. Further, the calculation unit 210 may calculate the white light MTF, the Strehl ratio, the Landolt's ring pattern, and the like, and display them on the display unit 230.
The calculation unit 210 returns to step S101 if the measurement is continued, and ends if the measurement is not continued (S123).

5. Modification Examples Modification examples in the above-described embodiment will be described below.
(Modification of automatic adjustment in independent mode)
FIG. 15 is a first modification of the automatic adjustment process in the independent mode of FIG. In the automatic adjustment processing in the independent mode shown in FIG. 11, first, the point image interval is adjusted in steps S201 to S209, and the point image level is adjusted to a predetermined value or more in steps S211 to S213. It is said.

  On the other hand, in the first modification of the automatic adjustment process in the independent mode shown in FIG. 15, contrary to the one shown in FIG. 11, the adjustment is first performed so that the point image level is equal to or higher than a predetermined value. In this embodiment, the point image interval is adjusted. Although the order of the processing shown in FIG. 11 is changed, the individual processing in each step is not changed, so that the same reference numerals as those in FIG. 11 are given and detailed description thereof is omitted here.

(Modification of the ophthalmologic measurement apparatus relating to the present embodiment)
FIG. 16 is a modification of the optical system of the ophthalmologic measurement apparatus 100 shown in FIG. An ophthalmic measuring apparatus 150 shown in FIG. 16 is obtained by adding an illumination optical system 80 for refractive power measurement and a light receiving optical system 90 for measuring refractive power to the ophthalmic measuring apparatus 100 shown in FIG. Both of these optical systems function during refractive power measurement.

  The illumination optical system 80 for refractive power measurement includes a refractive power measurement light source 81, a collimator lens 82, a refractive power measurement ring pattern 83, a relay lens 84, and a beam splitter 87. The illumination light beam emitted from the refractive power measurement light source 81 is converted into a parallel light beam by the collimator lens 82, and illuminates the ring-shaped pattern 83 for refractive power measurement. The illuminated light beam from the ring-shaped pattern 83 for measuring the refractive power becomes parallel by the relay lens 84 and passes through the stop 85 and the relay lens 86 conjugated with the pupil, and passes through the beam splitter 87 and passes through the first illumination optical system 10. The retina 61 of the eye 60 to be examined is illuminated via the common optical system 40. The ring-shaped pattern 83 for measuring refractive power has a positional relationship conjugate with the fundus of the subject's eye when measuring the subject's eye with normal vision.

  The light receiving optical system 90 for measuring refractive power includes a beam splitter 91, a relay lens 92, and a light receiving unit 93 for measuring refractive power. The reflected light beam from the retina 61 of the subject eye 60 illuminated by the ring reaches the beam splitter 91 via the common optical system 40, is reflected here, is collected by the relay lens 92, and then is received for refractive power measurement. The light is received by the unit 93 as a light reception signal for refractive power measurement. A refractive power measurement light-receiving signal indicating a refractive power measurement ring-shaped pattern image projected on the retina is sent to the arithmetic unit 210.

  The refractive power measuring light receiving portion 93 is preferably formed of a two-dimensional sensor. The calculation unit 210 obtains the refractive power of the eye to be examined from the ring-shaped pattern image for refractive power measurement projected on the retina based on the received light signal for refractive power measurement. Since the calculation for calculating the refractive power is disclosed in Japanese Patent No. 2580215, the details thereof are omitted here.

(Overall flowchart of modification)
FIG. 17 is a first modification of the overall flowchart of the ophthalmologic measurement apparatus according to this embodiment. In the overall flowchart shown in FIG. 10, in the interlocking mode, the first illumination optical system 10 and the first light receiving optical system 20 are changed in steps S102, S103, and S105 according to the level of the first light receiving signal of the first light receiving unit. It is configured to perform interlocking control and perform approximate position adjustment. On the other hand, in the modification shown in FIG. 17, the first illumination optical system 10 and the first light receiving optical system are measured based on the refractive power of the eye to be examined, which is obtained by measuring the refractive power in the interlock mode. The point which is set as the structure which moves 20 interlockingly differs. The difference will be described below.

  In the interlocking mode in FIG. 17, the refractive power of the eye to be examined is obtained by the calculation unit 210 based on the light receiving signal for refractive power measurement, and the first illumination optical system 10 and the first light receiving optical system 20 are based on the obtained refractive power. Linked control is performed to roughly adjust the position.

  First, the calculation unit 210 selects an interlocking mode, and performs alignment adjustment with the eye to be examined in parallel with it (S101). Next, the calculation unit 210 illuminates the retina 61 of the eye 60 with the refractive power measurement ring-shaped pattern 83 via the illumination optical system 80 for refractive power measurement, and receives the reflected light beam reflected from the retina 61 of the eye 60 for refractive power measurement. Based on the received light signal for refractive power measurement received by the unit 93, the refractive power of the eye 60 to be examined is obtained (S130). The calculation unit 210 moves the first illumination optical system 10 and the first light receiving optical system 20 in conjunction with each other to a position corresponding to the obtained spherical power component of refractive power (S131). The calculation unit 210 determines whether or not the movement adjustment has been completed. If the movement adjustment has not been completed, the calculation unit 210 returns to step S131. If completed, the calculation unit 210 proceeds to step S106, and mode selection is performed (S132). The determination of the end of the movement adjustment can be performed using an appropriate method such as stopping the first illumination optical system and the first light receiving optical system. Further, the following processing is the same as the flowchart shown in FIG.

(Second modification of automatic adjustment in independent mode)
FIG. 18 is a second modification of the automatic adjustment process in the independent mode. In the first modification of the overall flowchart of the ophthalmic measurement apparatus in FIG. 17, when the independent mode automatic adjustment process is selected (S107, 109), the second modification of the automatic adjustment process in the independent mode shown in FIG. May be executed.

  In the automatic adjustment in the independent mode in this modification, the calculation unit 210 performs interlocking control of the first illumination optical system 10 and the first light receiving optical system 20 based on the level of the first light receiving signal, and then each point image. The movement adjustment is individually performed based on the level, and the movement adjustment is individually performed based on the point image interval. The interlock control of the first illumination optical system 10 and the first light reception optical system 20 based on the level of the first light reception signal is the same as steps S102, S103, and S105 shown in FIG. The detailed explanation is omitted. Next, the process of performing the movement adjustment individually based on the individual point image levels, and further performing the movement adjustment individually based on the interval between the point images is the same as that shown in FIG. Detailed description thereof is omitted.

(Third modification of automatic adjustment in independent mode)
FIG. 19 shows a third modification of the automatic adjustment process in the independent mode. In the first modification of the overall flowchart of the ophthalmic measurement apparatus in FIG. 17, when automatic adjustment in the independent mode is selected (S107, 109), the third modification of the automatic adjustment processing in the independent mode shown in FIG. It may be configured to be executed.

  In the automatic adjustment in the independent mode in this modification, the interlocking control of the first illumination optical system 10 and the first light receiving optical system 20 is performed based on the level of the first light receiving signal, and then individually moved based on the point image interval. Adjustment is performed, and furthermore, movement adjustment is individually performed based on individual point image levels. The interlock control of the first illumination optical system 10 and the first light reception optical system 20 based on the level of the first light reception signal is the same as steps S102, S103, and S105 shown in FIG. The detailed explanation is omitted. Next, the process of performing individual movement adjustment based on the interval between point images and further performing individual movement adjustment based on individual point image levels is the same as that shown in FIG. Detailed description thereof is omitted.

FIG. 20 is a second modification of the overall flowchart of the ophthalmologic measurement apparatus according to this embodiment. In particular, when the refractive index of a portion of the eye changes significantly, such as when an initial nuclear cataract or refractive myopia is performed on an intense myopic eye, all image points are measurable even when adjusted in the independent mode. Occasional cases may not occur. In the second modification of the overall flowchart, a plurality of Hartmann images at different diopter positions are detected and combined to obtain the optical characteristics of the entire eye to be examined.
FIG. 21 is a Hartmann image in an eyeball having a different refractive power of a part of the eye. The Hartmann image shown in FIG. 21 is an example in which the vicinity of the center is a substantially normal eye, and a high myopia portion remains in the peripheral portion. FIG. 21A shows a state matched to the refractive power in the vicinity of the center, and FIG. 21B shows a state matched to the refractive power in the peripheral portion. At the time of measurement, it becomes possible to measure the refractive power of the entire eye to be examined from the point images of the vicinity of the center of FIG. 21A and the peripheral portion of FIG.

  In FIG. 20, the processes from step S101 to S113 are the same as the processes in FIG.

  The calculation unit 210 performs signal detection in a state adjusted in each mode, and stores the detected first received light signal in the storage unit (S140). The calculation unit 210 determines whether measurement can be sufficiently performed with the detected first light reception signal (S141). For example, it can be determined whether the measurement can be performed based on whether a Hartmann image can be recognized by a predetermined number or more, whether a predetermined interval is a predetermined number or more, or a predetermined level or more is a predetermined number or more.

  If the calculation unit 210 determines that the measurement is insufficient, the calculation unit 210 returns to step S113, performs independent mode manual adjustment processing, and the point images of the insufficient area appear clearly and at appropriate intervals. When the adjustment is completed, the process proceeds to the signal detection process of step S140, and a Hartmann image under another condition is detected and further stored in the storage unit. The detection of the Hartmann image may be repeated a plurality of times until a signal that can be measured by the composite Hartmann forming an image is obtained. Next, the calculation unit 210 forms a composite Hartmann image from the plurality of Hartmann images stored in the storage unit, and performs Zernike analysis (S142). The process for forming the composite Hartmann image will be described in detail below.

  When the point image of a certain area of the Hartmann image is stuck or blurred at a certain diopter position, the image can be acquired, and the diopter position can be changed to recognize it before. In other words, a method of moving to a position where a previously unrecognizable part can be recognized even if it becomes unrecognizable, acquiring an image here, and analyzing it in combination with the previously acquired image is shown.

For example, after acquiring two Hartmann images, the center of gravity of the point image at a certain diopter position (for example, the median position of the diopter values acquired on the two screens) is estimated from the center of gravity of the point images detected from each screen. be able to. The amount of movement of the point image is obtained from the image of the first light receiving unit. The amount of movement of the i-th point image △ _{x i,} and △ _{y i.} This amount of movement and wavefront aberration are related by the following partial differential equation.

Here, when representing the wavefront W deployment using Zernike polynomials Z _n ^m, it is as follows.

By changing the diopter position, the wavefront W is only Zernike coefficients C ₂ ⁰ corresponding to the diopter changes. It is considered that the center of gravity of the point image moves only by this change.
The centroid position (X _i1 , Y _i1 ) of the point image at the diopter position before the movement, the centroid position (X _i , Y _i ) of the point image at the diopter position to be estimated (analyzed), and the amount of movement by ΔX _i1 , Δ If Y _i1 , the Zernike coefficient change amount is Δ (C ₂ ⁰ ) ′, and the distance between the Hartmann plate 22 and the first light receiving unit 23 is F, the following relationship is established.

An equation for calculating the Zernike coefficient ΔC ₂ ⁰ from the diopter variation ΔS ₁ is expressed by the following equation.

However, r is a pupil radius (mm). The Zernike polynomial Z ₂ ⁰ is expressed by the following equation from FIG.

Therefore, the center-of-gravity position (X _ia , Y _ia ) of the point image at the estimated diopter position a is represented by the following formula, where the centroid position of the point image at the pre-movement diopter value used for estimation is (X _i1a , Y _i1a ): Can be expressed as

Further, the centroid position (X _ib , Y _ib ) of the point image at the diopter position b to be estimated (analyzed) is the centroid position of the point image at the moved diopter position used for estimation (X _i2b , Y _i2b ), If the diopter change amount is ΔS ₂ , it is similarly expressed by the following equation.

  By calculating the wavefront W based on the barycentric position obtained by combining these, it is possible to obtain a result in which both the barycentric positions obtained on the two screens are taken into account. For example, if i = 1 to 100, the point suitable for measurement at position a is i = 1 to 50, and the point suitable for measurement at position b is i = 51 to 100,

Thus, the position of the center of gravity of the composite point image is obtained. The combination of Hartmann images is not limited to two screens, and the same analysis can be performed from more images.
If Zernike analysis is performed using this, the overall optical characteristics can be obtained. Thereafter, optical characteristic calculation is performed in step 119, and the measurement result is displayed in step 121. The processing in steps S119 to S123 is the same as the processing with the same sign in the flowchart shown in FIG.

The figure which shows the schematic optical system 100 of the ophthalmologic measuring apparatus regarding this invention. The block diagram of a placido ring. 1 is a block diagram showing a schematic electrical system 200 of an ophthalmic measurement apparatus according to the present invention. Hartmann image when there is no misalignment on the projection side and the light receiving side. Explanatory drawing of the influence on a Hartmann image by the position shift of a projection side and a light-receiving side. Hartmann image at the time of occurrence of misalignment on the projection side. Hartmann's image when misalignment occurs on the receiving side. Hartmann image of an eyeball with non-uniform optical properties. Display diagram in the manual adjustment state. The flowchart which shows operation | movement of the ophthalmologic measurement apparatus with a manual wavefront measurement function. The flowchart of an independent mode automatic adjustment process. The flowchart of an independent mode manual adjustment process. Zernike polynomial (1). Zernike polynomial (2). The 1st modification of independent mode automatic adjustment processing. The modification of the outline optical system of an ophthalmology measuring device. The 1st modification of the whole flowchart of an ophthalmologic measurement apparatus. The 2nd modification of independent mode automatic adjustment processing. The 3rd modification of independent mode automatic adjustment processing. The 2nd modification of the whole flowchart of an ophthalmologic measurement apparatus. Hartmann's image of an eyeball with different refractive powers.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 1st illumination optical system 11, 72, 31, 51, 55 1st-5th light source part 12, 32, 34, 44, 52, 53 Condensing lens 20 1st light reception optical system 21 Collimating lens 22 Hartmann plate 23, 35 , 54 First to third light receiving units 30 Second light receiving optical systems 33, 43, 45 Beam splitter 40 Common optical system 42 Afocal lens 50 Adjustment optical system 60 Eye to be examined 70 Second illumination optical system 71 Platide ring 75 Third illumination Optical system 80 Refracting power measuring illumination system 90 Refracting power receiving optical system 100 Optical system 110 of ophthalmic measuring apparatus First moving means 120 Second moving means 150 Modification 200 of optical system of ophthalmic measuring apparatus Electricity of ophthalmic measuring apparatus System 210 Calculation unit 220 Control unit 230 Display unit 240 Memory 250 First drive unit 260 Second drive unit 270 Input unit 271 Mode changeover switch

Claims (4)

A first illumination optical system having a first light source that emits a light beam having a first wavelength, and illuminating the first illumination light beam from the first light source so as to be condensed near the fundus of the eye to be examined;
A first conversion member that converts a reflected light beam reflected from the fundus of the eye to be examined into at least 17 beams, and a first light receiving unit that receives a plurality of light beams converted by the first conversion member; A first light receiving optical system that leads to the first light receiving unit;
First moving means for moving the condensing position of the first illumination optical system;
Second moving means for optically moving the first light receiving section and the first conversion member;
The tilt angle data of the light beam obtained by the first light receiving unit under different conditions by the first moving means or the second moving means are combined, and Zernike analysis is performed based on the combined data to obtain the optical characteristics of the eye to be examined. An ophthalmologic measurement apparatus comprising a calculation unit. Furthermore, a mode switching unit capable of switching between an interlocking mode for interlocking the movement operation of the first moving unit and the second moving unit and an independent mode that can be controlled independently,
The calculation unit is configured to combine the tilt angle data of the light flux obtained by the first light receiving unit under different conditions in each mode, perform Zernike analysis based on the combined data, and obtain optical characteristics of the eye to be examined. The ophthalmic measurement apparatus according to claim 1.   The arithmetic unit further moves the first illumination optical system and the first light receiving optical system in conjunction with each other by the first and second moving means when the value based on the first light receiving signal is not a predetermined level. The ophthalmologic measurement apparatus according to claim 1 or 2, wherein A refractive power measurement illumination optical system that irradiates a retina with a pattern for refractive power measurement;
A light receiving optical system for refractive power measurement that receives a pattern image projected on the retina of the eye to be examined;
The arithmetic unit further obtains a refractive power from the pattern image received by the refractive power measurement light-receiving optical system, and based on the refractive power, the first and second moving means cause the first illumination optical system and The ophthalmologic measurement apparatus according to claim 1, wherein the first light receiving optical system is configured to move in conjunction with each other.

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