JP5566711B2 - Ophthalmic equipment - Google Patents

Description

  The present invention relates to an ophthalmologic apparatus capable of measuring the shape of the cornea.

  A keratometer is known as an apparatus for measuring the shape of the cornea. A keratometer is an apparatus that quantitatively evaluates the corneal shape of an eye to be examined (see, for example, Patent Document 1). The keratometer projects point light (bright spots) from a plurality of light sources arranged in a circular shape onto the cornea, takes a corneal reflection image of these bright spots, and based on the displacement of the corneal reflection image group with respect to a circle, Evaluate the shape.

  As an apparatus for measuring a corneal shape with higher accuracy than a keratometer, an ophthalmologic apparatus including a placido ring illuminator is known (see, for example, Patent Document 2). The placido ring illuminator is a device that projects a plurality of bright spots arranged concentrically. The device described in Patent Document 2 is a microscope for ophthalmic surgery in which a placido ring illuminator is attached.

JP 2007-215956 A JP-A-8-66369

  In the measurement of the corneal shape, the displacement of the corneal reflection image with respect to the circle is referred to as described above. At this time, the displacement is obtained on the assumption that a plurality of light sources are arranged in a perfect circle. However, it is difficult to arrange a plurality of bright spots projected on the cornea in a perfect circle for the following reasons.

  First, there are manufacturing reasons. In other words, the design is made such that a plurality of light sources are arranged in a perfect circle, but when the light sources are attached in the manufacturing stage, the attachment position is inevitably displaced. For example, the light source may be mounted at a position deviating from the designed mounting position due to variations in the thickness of solder when the light source is mounted.

  There is also a problem of light emission unevenness of the light source. In other words, it is extremely difficult to emit light of uniform intensity from the light emitting surface of the light source, so strong light is emitted from only a part of the light emitting surface, or light is not emitted from a part of the light emitting surface. Occurs. Then, the arrangement of the plurality of bright spots projected on the cornea deviates from the original perfect circle.

  It is also conceivable to provide a mask in order to deal with manufacturing problems, or to provide a diffusion plate to deal with the problem of uneven light emission. However, new problems such as a complicated structure of the apparatus and an increase in manufacturing cost arise. If a diffuser plate is used, a ring-shaped light beam is projected onto the cornea instead of a plurality of bright spots.

  In this way, if the plurality of bright spots projected on the cornea are not arranged in a perfect circle, the above assumption is broken and the measurement accuracy is lowered.

  In addition, as described in Patent Document 2, when a projection apparatus having a plurality of light sources is mounted on an ophthalmologic apparatus, the direction in which the projection apparatus is mounted may be appropriately changed. For example, when using a surgical microscope with an assistant microscope or slit illumination device attached, the mounting direction of the projection device may be changed according to the mounting direction. When the mounting direction of the projection device changes, the directions of a plurality of lights (or ring-shaped light beams) arranged in a distorted circular shape and projected onto the cornea also change. Then, due to the difference in the mounting direction of the projection device, different measurement results can be obtained even for the same eye to be examined, and the reproducibility of the measurement is lowered.

  In some ophthalmologic apparatuses capable of binocular observation, the optical axes of the left and right observation optical systems are displaced with respect to the optical axis of the objective lens. In such a configuration, the corneal reflection light passes through the vicinity of the edge of the objective lens and then enters the left and right optical systems. Then, the cross-sectional shape of the corneal reflected light changes due to the prism effect or the like at the passage position (near the edge), and the accuracy of the evaluation of the corneal shape is reduced.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide an ophthalmic apparatus capable of accurately measuring the shape of the cornea.

In order to achieve the above object, the invention according to claim 1 is a projection means for projecting a plurality of bright spots arranged in a substantially circular shape onto the cornea of the eye to be examined, and a state in which the plurality of bright spots are projected An ophthalmologic apparatus for calculating an evaluation value of the shape of the cornea based on the positions of the images of the plurality of bright spots depicted in the photographed image. Bright spot image position information indicating the positions of the plurality of bright spot images described in the astigmatism photographed image obtained by photographing the astigmatic cornea model eye with the bright spot projected thereon by the photographing means in advance Storage means for storing, and positions of the images of the plurality of bright spots depicted in a cornea photographed image obtained by photographing the cornea of the eye to be examined in a state where the plurality of bright spots are projected by the photographing means, Correction based on the bright spot image position information, and the corrected image positions of the bright spots. And a calculating means for calculating the evaluation value of the cornea on the basis of, on the bright spot image position information, displacement relative to the true circle of the image of the plurality of bright spots in the non-astigmatic imaging image is recorded And the calculating means corrects the positions of the plurality of bright spot images in the cornea image so as to cancel the displacement, and uses the perfect circle as the correct circle. And a perfect circle calculation means for obtaining an approximate circle for the position, wherein the evaluation value is calculated based on the position of the image after the correction .
The invention according to claim 2 is the ophthalmologic apparatus according to claim 1, wherein the perfect circle calculation means applies the least square method to the positions of the images of the plurality of bright spots, and the Ru asked, characterized in that.
According to a third aspect of the present invention, a projection means for projecting a plurality of bright spots arranged in a substantially circular shape onto the cornea of an eye to be examined, and the cornea in a state in which the plurality of bright spots are projected are photographed. An ophthalmic apparatus that calculates an evaluation value of the shape of the cornea based on the positions of the images of the plurality of bright spots depicted in the photographed image, wherein the plurality of bright spots are projected Storage means for preliminarily storing bright spot image position information indicating the positions of the plurality of bright spot images depicted in the astigmatism photographed image obtained by photographing the astigmatic corneal model eye in the state by the photographing means; The position of the plurality of bright spot images described in the cornea photographed image obtained by photographing the cornea of the eye to be inspected with the plurality of bright spots projected by the photographing means, the bright spot image position information. Based on the position of the image of the plurality of bright spots after the correction Computing means for calculating the evaluation value, and the projection means includes a light source holding means in which a plurality of light sources for projecting the plurality of bright spots are installed in a substantially circular shape and is attachable to and detachable from the apparatus housing. Light source control means for controlling a specific light source of the plurality of light sources to be in a lighting state different from the other light sources, and the computing means is configured to control the plurality of bright spots based on the lighting state. Selection means for selecting an image corresponding to the specific light source, the position of the image selected for the astigmatism image, and the position of the image selected for the cornea image In comparison, the mounting direction displacement calculating means for determining the displacement in the mounting direction of the light source holding means between the time of shooting the astigmatism image and the time of shooting the cornea image, Based on the displacement, the bright spot image Luminescent spot image correspondence means for associating the plurality of bright spot images indicating their positions with the position information and the plurality of bright spot images in the cornea image, and based on the result of the correspondence calculating the evaluation value, it shall be the said.
According to a fourth aspect of the present invention, a projection unit that projects a plurality of bright spots arranged in a substantially circular shape onto the cornea of an eye to be examined, and the cornea in a state in which the plurality of bright spots are projected is photographed. An ophthalmic apparatus that calculates an evaluation value of the shape of the cornea based on the positions of the images of the plurality of bright spots depicted in the photographed image, wherein the plurality of bright spots are projected Storage means for preliminarily storing bright spot image position information indicating the positions of the plurality of bright spot images depicted in the astigmatism photographed image obtained by photographing the astigmatic corneal model eye in the state by the photographing means; The position of the plurality of bright spot images described in the cornea photographed image obtained by photographing the cornea of the eye to be inspected with the plurality of bright spots projected by the photographing means, the bright spot image position information. Based on the position of the image of the plurality of bright spots after the correction Computing means for calculating the evaluation value, and the projection means includes a light source holding means in which a plurality of light sources for projecting the plurality of bright spots are installed in a substantially circular shape and is attachable to and detachable from the apparatus housing. Detecting means for detecting the mounting direction of the light source holding means with respect to the apparatus housing, and the computing means is configured to detect the mounting direction detected when shooting the astigmatism image and when shooting the cornea image. Based on the obtained displacement in the mounting direction, the mounting direction displacement calculating means for determining the displacement between the detected mounting direction and the plurality of bright spots indicating the positions in the bright spot image position information. wherein an image, and a luminescent spot image corresponding means for associating the image of the plurality of bright spots in the cornea imaging image, you calculate the evaluation value based on the correlation result, characterized in that .
The invention according to claim 5 is the ophthalmologic apparatus according to claim 3 or claim 4 , wherein the objective lens and an illumination optical system for irradiating the eye to be examined with illumination light through the objective lens are provided. An observation optical system that guides the reflected light of the illumination light from the eye to be examined via the objective lens to an eyepiece through a zoom lens system, and the plurality of light sources includes the objective lens and the eye to be examined. Between the optical path of the illumination light and the optical path of the reflected light, and the calculation means calculates the astigmatic axis direction of the cornea of the eye to be examined as the evaluation value, and the calculated astigmatism a light source disposed at a position corresponding to the axial direction includes a light source identification means for identifying from among said plurality of light sources, the further Ru comprising a lighting state changing means for changing the lighting state of the specified light source, characterized in that And
The invention according to claim 6 is the ophthalmologic apparatus according to claim 5 , wherein the observation optical system guides the reflected light passing through the objective lens to left and right eyepieces, respectively. Each optical axis of the left and right optical systems is displaced with respect to the optical axis of the objective lens, and one of the left and right optical systems has a reflected light beam directed to the eyepiece lens. A beam splitter that divides the light beam toward the image capturing unit, and the storage unit is configured to determine a position of the image of the light beam depicted in the image captured by the image capturing unit of a substantially circular light beam incident on the objective lens. Light beam image position information is stored in advance, and the calculation unit corrects the positions of the plurality of bright spot images depicted in the cornea image based on the light flux image position information together with the bright spot image position information. , The corrected plurality of the plurality It calculates the evaluation value based on the position of the image of the point, characterized in that.
The invention according to claim 7 is the ophthalmologic apparatus according to claim 6 , wherein the light flux image position information records a displacement of the image of the light flux with respect to a perfect circle, and the computing means the position of the image of the plurality of bright spots in the cornea imaging image, corrected so as to cancel the displacement, characterized in that.
According to an eighth aspect of the present invention, there is provided an objective lens, an illumination optical system that irradiates the eye to be inspected with illumination light through the objective lens, and reflected light of the illumination light by the eye to be examined through the objective lens. An observation optical system having left and right optical systems that respectively guide the left and right eyepieces via a zoom lens system, and a projection unit that projects a plurality of bright spots arranged in a substantially circular shape onto the cornea of the eye to be examined. An imaging unit that images the cornea in a state where the plurality of bright spots are projected, and an operation that calculates an evaluation value of the shape of the cornea based on the positions of the images of the plurality of bright spots depicted in the captured image And storage means for preliminarily storing light beam image position information indicating the position of the image of the light beam depicted in the image taken by the photographing means of the substantially circular light beam incident on the objective lens, The optical axes of the left and right optical systems are The optical system is displaced with respect to the optical axis of the objective lens, and one of the left and right optical systems includes a beam splitter that divides the reflected light into a light beam directed toward the eyepiece lens and a light beam directed toward the photographing unit, The computing means calculates the position of the image of the plurality of bright spots depicted in the cornea photographed image obtained by photographing the cornea of the eye to be examined in a state where the plurality of bright spots are projected by the photographing means. corrected based on the image position information, calculates the evaluation value of the cornea based on the position of the image of the plurality of bright points of the corrected, a ophthalmologic apparatus characterized by and this.
The invention according to claim 9 is the ophthalmologic apparatus according to claim 8 , wherein the light flux image position information records a displacement of the image of the light flux with respect to a perfect circle, and the computing means The position of the plurality of bright spot images in the cornea image is corrected so as to cancel the displacement.

  The first aspect of the ophthalmologic apparatus according to the present invention is based on the bright spot image position information indicating the positions of a plurality of bright spot images depicted in the astigmatism photographed image. The position of the bright spot image is corrected, and an evaluation value of the shape of the cornea is calculated based on the corrected position of the image.

  In this way, by correcting the position of the image in the cornea image by referring to the position shift of the bright spot image (bright spot image position information) in the astigmatism state, the influence of the shift of the light source mounting position is eliminated. Thus, the evaluation value can be obtained.

  Thereby, even when the plurality of bright spots projected on the cornea are not arranged in a perfect circle, the shape of the cornea can be accurately measured.

  According to a second aspect of the ophthalmologic apparatus of the present invention, the optical axes of the left and right optical systems of the observation optical system are displaced with respect to the optical axis of the objective lens, and one side of the left and right optical systems I am going to shoot the cornea. In the second aspect, the positions of the plurality of bright spot images depicted in the cornea image obtained by photographing the cornea of the eye to be examined in a state in which the plurality of bright spots are projected, The correction is performed based on the information, and the evaluation value of the shape of the cornea is calculated based on the positions of the corrected images of the bright spots. The light beam image position information is information indicating the position of the image of the light beam depicted in the photographed image of the substantially circular light beam incident on the objective lens.

  Thereby, even when the optical axis of the objective lens and the optical axes of the left and right optical systems are displaced, the shape of the cornea can be accurately measured.

It is the schematic showing an example of the external appearance structure of embodiment of the ophthalmologic apparatus which concerns on this invention. It is the schematic showing an example of the structure of the projection image formation part in embodiment of the ophthalmologic apparatus which concerns on this invention. It is the schematic showing an example of the structure of the projection image formation part in embodiment of the ophthalmologic apparatus which concerns on this invention. It is the schematic showing an example of the structure of the optical system in embodiment of the ophthalmologic apparatus which concerns on this invention. It is the schematic showing an example of the structure of the optical system in embodiment of the ophthalmologic apparatus which concerns on this invention. It is a schematic block diagram showing an example of the structure of the control system in embodiment of the ophthalmologic apparatus which concerns on this invention. It is a schematic block diagram showing an example of a structure of the control system in the modification of embodiment of the ophthalmologic apparatus which concerns on this invention.

  An example of an embodiment of an ophthalmologic apparatus according to the present invention will be described in detail with reference to the drawings. In the following embodiments, a case where the configuration according to the present invention is applied to an ophthalmic surgical microscope will be described. The application target of the configuration according to the present invention is not limited to an ophthalmic surgical microscope, and may be any ophthalmologic apparatus capable of measuring the shape of the cornea, such as a keratometer and an autorefractometer / keratometer.

[Constitution]
[Appearance structure]
An external configuration of the microscope for ophthalmic surgery 1 will be described with reference to FIG. The microscope for ophthalmologic surgery 1 includes a support 2, a first arm 3, a second arm 4, a driving device 5, a microscope 6 and a foot switch 8 as in the conventional art.

  In addition to these, the microscope for ophthalmic surgery 1 may include an assistant microscope similar to the conventional one. The assistant's microscope is mounted in a different direction from the microscope 6 used by the operator. The mounting position of the assistant's microscope can be changed as appropriate according to the layout of the operating room, the position of the affected part, and the like.

  The drive device 5 includes an actuator such as a motor. The driving device 5 moves the microscope 6 in the vertical direction and the horizontal direction in accordance with an operation using the foot switch 8 or the like. Thereby, the microscope 6 can be moved three-dimensionally.

  The lens barrel 10 of the microscope 6 houses various optical systems, drive systems, control systems, and the like. An inverter unit 12 is provided on the upper portion of the lens barrel unit 10. When the observation image of the patient's eye (eye to be examined) E (the eye to be examined) is obtained as an inverted image, the inverter unit 12 converts the observation image into an erect image. A pair of left and right eyepieces 11 </ b> L and 11 </ b> R are provided on the upper portion of the inverter unit 12. An observer (operator or the like) can view the patient's eye E binocularly by looking into the left and right eyepieces 11L and 11R.

  The microscope for ophthalmologic surgery 1 includes a projection image forming unit 13 as a characteristic configuration. The projection image forming unit 13 projects a light beam onto the patient's eye E to form a predetermined projection image on the patient's eye E. The projected image in this embodiment is a plurality of bright spot images arranged in a substantially circular shape. The projection image forming unit 13 constitutes an example of the “projection unit” of the present invention together with a support member 17 and a control unit 60 described later.

  A configuration example of the projection image forming unit 13 is shown in FIGS. Here, reference numeral 14 in FIG. 2 represents a photographing unit. The photographing unit 14 stores a TV camera 56 described later. FIG. 3 shows a configuration when the head portion 131 of the projection image forming unit 13 is viewed from below (that is, the patient's eye E side, in other words, the opposite side of the lens barrel unit 10).

  As shown in FIGS. 2 and 3, the head portion 131 is a disk-shaped member. As shown in FIG. 3, a plurality of LEDs 131-i (i = 1 to N) are provided on the lower surface of the head portion 131. The LED group 131-i is arranged in a substantially circular shape. In this embodiment, 36 LEDs 131-i are provided at approximately equal intervals (N = 36). That is, the LED group 131-i is arranged at an angle of approximately 10 degrees with respect to the center position of the LED group 131-i. In other words, considering the line segment connecting each LED 131-i and the center position, the line segments related to the two adjacent LEDs 131-i and 131- (i + 1) form an angle of approximately 10 degrees at the center position. Intersect. The LED group 131-i is arranged and used between the objective lens 15 and the patient's eye E at a position deviating from the optical path of the illumination light and the optical path of the reflected light from the patient's eye E.

  As described above, the plurality of LEDs 131-i are not arranged in a perfect circle due to a problem such as a mounting position shift in the manufacturing stage. In FIG. 3, such an arrangement state is exaggerated. For example, the LED 131-k is installed at a position deviating from the tendency of the arrangement of the LEDs 131-i in the vicinity thereof (arranged along the arc).

  Among the LED groups 131-i, one corresponding to the horizontal direction and the vertical direction can be configured to output a color different from that corresponding to the other direction. In other words, the LEDs at positions corresponding to the astigmatism axis direction (astigmatism axis angle) of 0 degrees, 90 degrees, 180 degrees, and 270 degrees (LEDs 131-1, 131-10, 131-19, and 131-28, respectively) It can be configured to output a light flux of a different color from the LED 131-i (i ≠ 1, 10, 19, 28). For example, red LEDs can be used as the LEDs 131-1, 131-10, 131-19, 131-28, and green LEDs can be used as the other LEDs 131-i (i ≠ 1, 10, 19, 28). Thereby, it is possible to easily recognize the horizontal direction and the vertical direction of the astigmatic axis. The horizontal direction means a horizontal direction (left-right direction) in the field of view of the microscope 6 when viewed from the observer (operator) side, and the vertical direction means a direction orthogonal to the horizontal direction.

  Further, some of the LEDs 131-1, 131-10, 131-19, and 131-28 may output a light flux having a color different from that of the other LEDs. For example, only the LED 131i corresponding to an angle of 0 degrees can be configured to output a different color from other LEDs (i ≠ 1).

  Further, it is not necessary to configure all of the LEDs 131-1, 131-10, 131-19, and 131-28 to output a light beam of the same color (red in the above example). For example, a red LED is used as each LED 131-1, 131-19, a white LED is used as each LED 131-10, 131-28, and a green LED is used as another LED 131-i (i ≠ 1, 10, 19, 28). Can be used. Thereby, it is possible to easily identify the horizontal direction and the vertical direction.

  In addition, instead of making the horizontal direction and the vertical direction recognizable according to the output color of the light source as described above, the same effect can be achieved with other configurations. For example, the direction can be identified by changing the brightness of the output light.

  The LED group 131-i is an example of the “plurality of light sources” of the present invention. Here, each light source does not need to be an LED, and any device capable of outputting a light beam can be used. Further, the plurality of light sources may not be arranged at equal intervals. Since FIG. 3 is a bottom view, the arrangement order of the LED groups 131-i is set in the opposite direction (reverse direction) to the general astigmatic axis setting direction. Thereby, the corneal reflection light (Purkinje image) of the light beam output from the LED group 131-i is observed or photographed as a general astigmatic axis setting direction.

  In this embodiment, 36 light sources are provided, but the number of light sources to be installed is arbitrary. However, as will be described later, in this embodiment, since the astigmatic axis direction of the patient's eye E is measured based on the Purkinje image of the light flux output from the LED group 131-i, the accuracy and accuracy of this measurement can be ensured. It is desirable that a number of light sources be provided.

  In addition, the number of light sources can be appropriately set according to the accuracy required when the operator visually recognizes the astigmatic axis direction and the main meridian arrangement direction of the toric IOL (Intra Ocular Lens). It is. For example, in this embodiment, since the light sources are arranged at intervals of 10 degrees, the astigmatic axis direction and the like can be presented in units of at least 10 degrees. In order to present the astigmatic axis direction and the like with higher accuracy, the number of light sources corresponding to the accuracy (for example, 72 in the case of 5 degree units) is provided. The same is true for lower accuracy.

  In this embodiment, a plurality of individually configured light sources (LED groups 131-i) are provided, but the present invention is not limited to this. For example, a similar function can be obtained by providing a display device (for example, an LCD (liquid crystal display)) on the lower surface of the head portion 131 and displaying a plurality of bright spots with this display device. In this case, the pixel of the display device that forms each bright spot corresponds to a “light source”.

  An objective lens unit 16 is provided at the lower end of the lens barrel unit 10. The objective lens unit 16 stores the dictated objective lens 15. A support member 17 is provided in the vicinity of the objective lens unit 16. The support member 17 is formed from the objective lens portion 16 toward the side.

  A through-hole extending in the vertical direction is formed in the distal end portion 17 a of the support member 17. An arm 133 is inserted into the through hole. The arm 133 is slidable in the through hole. Thereby, the arm 133 can be moved in the vertical direction (the direction indicated by the double-sided arrow A in FIG. 2) with respect to the distal end portion 17a. Here, the microscope 6 side is the upward direction, and the patient's eye E side is the downward direction.

  A drop prevention part 134 is provided at the upper end of the arm 133. The fall prevention part 134 is a plate-like member having a diameter larger than the diameter of the through hole. Thereby, the fall prevention unit 134 prevents the arm 133 from falling off the tip portion 17a.

  A head connection portion 132 is provided at the lower end of the arm 133. The head connection part 132 connects the head part 131 to the arm 133 so that the surface on which the LED 131-i is provided faces downward.

  With such a configuration, the head part 131, the head connection part 132, the arm 133, and the fall prevention part 134 (that is, the projection image forming part 13) are movable in the vertical direction with respect to the tip part 17a. For example, the user moves the projection image forming unit 13 by holding the arm 133 or the like. It is also possible to configure the projection image forming unit 13 to be moved electrically by using a driving means such as a motor.

  A connecting hook 18 is provided on the lower surface of the support member 17. The connecting hook 18 is configured to be engageable with an engaging portion (not shown) of the projection image forming portion 13. This engaging part is provided in the head connection part 132, for example. When the projection image forming unit 13 is moved upward, the engaging unit and the connecting hook 18 are engaged to prohibit the vertical movement of the projection image forming unit 13. This engagement relationship can be released by a predetermined operation (for example, pressing a predetermined button). The configuration of the connecting hook 18 and the engaging portion is arbitrary.

  With the configuration described above, the LED group 131-i is held so as to be movable along the optical axis direction of the objective lens 15. The support member 17, the head part 131, the head connection part 132, the arm 133, and the fall prevention part 134 are an example of the “light source holding means” in the present invention. The holding means is not limited to the above configuration. As long as a plurality of light sources are movably held along the optical axis direction of the objective lens, the specific structure of the holding means is arbitrary.

  The head part 131 is configured to be detachable from the microscope 6 (the lens barrel part 10 and the objective lens part 16). Here, the head portion 131 may be configured to be detachable from the head connecting portion 132, the head connecting portion 132 may be configured to be detachable from the arm 133, or the tip portion 17a is a support member. The support member 17 may be configured to be detachable from the objective lens unit 16 (or the lens barrel unit 10). Any known configuration can be applied as the mechanism that enables such attachment and detachment.

[Configuration of optical system]
Next, the optical system of the microscope for ophthalmologic surgery 1 will be described with reference to FIGS. 4 and 5. Here, FIG. 4 is a view of the optical system viewed from the left side as viewed from the operator. FIG. 5 is a view of the optical system viewed from the operator side. In addition to the configuration shown in FIGS. 4 and 5, an optical system for an assistant to observe the patient's eye E, that is, an assistant's microscope may be provided.

  The assistant's microscope is disclosed in, for example, Japanese Patent Application Laid-Open No. 2006-280805. This document describes that the assistant's microscope is configured to be detachable, and that the position of the assistant's microscope can be changed.

  In this embodiment, the directions such as up and down, left and right, and front and rear are directions seen from the operator side unless otherwise specified. In addition, about the up-down direction, let the direction which goes to the observation object (patient eye E) from the objective lens 15 be a downward direction, and let this opposite direction be an upper direction.

  The aforementioned LED group 131-i is provided at a position below the objective lens 15 (position between the objective lens 15 and the patient's eye E). 4 and 5, only the LEDs 131-i and 131-j (i, j = 1 to N, i ≠ j) located at both ends when viewed from the viewpoint direction are described.

  The term “between the objective lens 15 and the patient's eye E” means between the position (height position) of the objective lens and the position (height position) of the patient eye E in the vertical direction (that is, The position in the front-rear direction is not considered). The LED group 131-i is generally arranged in an annular shape so as not to block the illumination light and its reflected light. The diameter of the substantially annular ring can be arbitrarily set within a range in which projection images (bright spot images) arranged in a substantially annular shape can be formed on the cornea of the patient's eye E.

  The observation optical system 30 will be described. As shown in FIG. 5, the observation optical system 30 is provided in a pair of left and right. The left observation optical system 30L is called a left observation optical system, and the right observation optical system 30R is called a right observation optical system. Symbol OL indicates the optical axis (observation optical axis) of the left observation optical system 30L, and symbol OR indicates the optical axis (observation optical axis) of the right observation optical system 30R. The left and right observation optical systems 30L and 30R are disposed so as to sandwich the optical axis O of the objective lens 15.

  As in the conventional case, the left and right observation optical systems 30L and 30R are respectively a zoom lens system 31, a beam splitter 32 (only the right observation optical system 30R), an imaging lens 33, an image erecting prism 34, and an eye width adjustment prism 35. A field stop 36 and an eyepiece 37.

  The zoom lens system 31 includes a plurality of zoom lenses 31a, 31b, and 31c. Each of the zoom lenses 31a to 31c can be moved in a direction along the observation optical axis OL (or the observation optical axis OR) by a driving mechanism (not shown). Thereby, the magnification at the time of observing or photographing the patient's eye E is changed.

  The beam splitter 32 of the right observation optical system 30R separates part of the observation light guided from the patient's eye E along the observation optical axis OR and guides it to the TV camera imaging system. The TV camera imaging system includes an imaging lens 54, a reflection mirror 55, and a TV camera 56. The television camera imaging system is stored in the imaging unit 14.

  The TV camera 56 includes an image sensor 56a. The image pickup device 56a is configured by, for example, a charge coupled devices (CCD) image sensor, a complementary metal oxide semiconductor (CMOS) image sensor, or the like. As the image sensor 56a, an element having a two-dimensional light receiving surface (area sensor) is used. The TV camera 56 is an example of the “photographing means” of the present invention.

  When the ophthalmic surgical microscope 1 is used, the light receiving surface of the imaging device 56a is, for example, a position optically conjugate with the surface of the cornea of the patient's eye E, or a depth from the apex of the cornea by ½ of the corneal curvature radius. It is arranged at a position optically conjugate with a position away in the direction.

  The image erecting prism 34 converts the inverted image into an erect image. The eye width adjustment prism 35 is an optical element for adjusting the distance between the left and right observation lights according to the eye width of the operator (the distance between the left eye and the right eye). The field stop 36 blocks the peripheral region in the cross section of the observation light and limits the operator's visual field.

  Next, the illumination optical system 20 will be described. As shown in FIG. 4, the illumination optical system 20 includes an illumination light source 21, an optical fiber 21a, an exit aperture stop 26, a condenser lens 22, an illumination field stop 23, a slit plate 24, a collimator lens 27, and an illumination prism 25. Is done.

  The illumination field stop 23 is provided at a position optically conjugate with the front focal position of the objective lens 15. The slit hole 24a of the slit plate 24 is formed at a position optically conjugate with the front focal position.

  The illumination light source 21 is provided outside the lens barrel 10 of the microscope 6. One end of an optical fiber 21 a is connected to the illumination light source 21. The other end of the optical fiber 21 a is disposed at a position facing the condenser lens 22 in the lens barrel 10. The illumination light output from the illumination light source 21 is guided by the optical fiber 21 a and enters the condenser lens 22.

  An exit aperture stop 26 is provided at a position facing the exit port (fiber end on the condenser lens 22 side) of the optical fiber 21a. The exit aperture stop 26 acts to shield a partial region of the exit port of the optical fiber 21a. When the shielding area by the exit aperture stop 26 is changed, the emission area of the illumination light is changed. Thereby, the irradiation angle by the illumination light, that is, the angle formed by the incident direction of the illumination light with respect to the patient's eye E and the optical axis O of the objective lens 15 can be changed.

  The slit plate 24 is formed of a disk-shaped member having a light shielding property. The slit plate 24 is provided with a light-transmitting portion including a plurality of slit holes 24 a having a shape corresponding to the shape of the reflecting surface 25 a of the illumination prism 25. The slit plate 24 is moved in a direction perpendicular to the illumination optical axis O ′ (direction of a double-headed arrow B shown in FIG. 4) by a driving mechanism (not shown). As a result, the slit plate 24 is inserted into and removed from the illumination optical axis O ′.

  The collimator lens 27 converts the illumination light that has passed through the slit hole 24a into a parallel light flux. The illumination light that has become a parallel light beam is reflected by the reflecting surface 25 a of the illumination prism 25 and projected onto the patient's eye E via the objective lens 15. Illumination light (a part) projected onto the patient's eye E is reflected by the cornea. Reflected light (sometimes referred to as observation light) of illumination light by the patient's eye E enters the observation optical system 30 via the objective lens 15. With such a configuration, binocular observation of an enlarged image of the patient's eye E is possible.

[Control system configuration]
Next, the control system of the microscope for ophthalmic surgery 1 will be described with reference to FIG. In FIG. 6, a part of the control system is omitted. The omitted parts include the drive device 5, the drive mechanism of the slit plate 24, the drive mechanism of the zoom lens system 31, and the like.

(Control part)
The control system of the microscope for ophthalmic surgery 1 is configured with a control unit 60 as a center. The control unit 60 is provided at an arbitrary part of the microscope for ophthalmic surgery 1 (for example, inside the support column 2). The same applies to the storage unit 70 and the arithmetic processing unit 80. Note that a computer may be provided separately from the configuration shown in FIG. 1 and used as the control unit 60, the storage unit 70, and the arithmetic processing unit 80.

  The control unit 60 controls each part of the microscope for ophthalmic surgery 1. The control unit 60 includes a microprocessor and a memory in the same manner as a normal computer. The control unit 60 is provided with an LED control unit 61.

(LED control unit)
The LED control unit 61 controls the LED group 131-i. In particular, the LED control unit 61 controls a specific LED 131-n in the LED group 131-i so as to be in a lighting state different from that of the other LED groups 131-i (i ≠ n).

  As a control example of this lighting state, the LED control unit 61 blinks a specific LED 131-n and continuously lights the other LED group 131-i. Here, the blinking means that the LEDs 131-i and 131- (i + 18) are repeatedly turned on and off at a predetermined time interval (for example, every one second). The continuous lighting is to keep the LED 131-j lit until an instruction to turn it off is given.

  As another example, the LED control unit 61 can change the color of output light from a specific LED 131-n and the color of output light from another LED group 131-i. Further, the brightness of the output light from the specific LED 131-n and the size of the bright spot may be different from those of the other LED groups 131-i. In this case, the specific LED 131-n and the other LED group 131-i can be configured by different types of LEDs.

  The above is only an example of lighting state control. The control of the lighting state is not limited as long as the specific LED 131-n (the bright spot image) can be identified in all the LED groups 131-i (the bright spot image). . The LED control unit 61 that controls the lighting state is an example of the “light source control unit” in the present invention.

  Further, the LED control unit 61 changes the lighting state of the LED 131 -m specified by the light source specifying unit 82 described later. As an example of this control, the LED control unit 61 causes the identified LED 131-m to blink, or causes the LED 131-m to output light having a color different from that of the other LED 131-i. The LED control unit 61 is an example of the “lighting state changing unit” in the present invention.

  The LED 131-m is disposed at a position corresponding to the astigmatic axis direction of the patient's eye E. The position corresponds to the position corresponding to the main meridian direction (strong main meridian direction or weak main meridian direction) of the cornea of the patient's eye E, or the arrangement direction of the main meridian (strong main meridian or weak main meridian) of the toric IOL. Such as location.

(Memory part)
The storage unit 70 stores various information. The control unit 60 executes a process for storing information in the storage unit 70 and a process for reading information from the storage unit 70. The storage unit 70 stores bright spot image position information 71. The bright spot image position information 71 is generated by analyzing an image (astigmatism photographed image) obtained by photographing an astigmatic corneal model eye in a state where a plurality of bright spots based on the plurality of LEDs 131-i are projected. Information indicating the positions of a plurality of bright spot images depicted in the astigmatism photographed image. The storage unit 70 is an example of the “storage unit” in the present invention.

  The bright spot image position information 71 will be described in more detail. The bright spot image position information generation unit 81 will also be described here. An astigmatic corneal model eye is a model eye including a corneal model that does not have astigmatism. As a model eye, for example, a Gullstrand type eye is known.

  When the bright spot image position information 71 is generated, the following measurement is performed using an astigmatic corneal model eye. First, the apparatus optical system is aligned with the astigmatic corneal model eye. Further, the plurality of LEDs 131-i are turned on by bringing the head portion 131 close to the astigmatic corneal model eye. Thereby, the bright spot based on the plurality of LEDs 131-i is projected onto the corneal portion of the astigmatic corneal model eye. The astigmatic corneal model eye in this state is photographed by the TV camera 56. A bright spot image (Purkinje image) is depicted in the astigmatism photographed image thus obtained. The control unit 60 sends this astigmatism photographed image to the arithmetic processing unit 80.

(Bright spot image position information generator)
The bright spot image position information generation unit 81 generates bright spot image position information 71 by analyzing the astigmatism photographed image. An example of this process will be described. First, the bright spot image position information generation unit 81 specifies the position of each bright spot image based on the pixel value of each pixel constituting the astigmatism photographed image. This process can be executed by extracting a pixel having a higher pixel value (luminance value) than the neighboring pixels.

  In this process, it is also possible to apply a filter process or the like that excludes pixels with low luminance values. In addition, threshold processing regarding luminance values can also be applied. It is also possible to perform processing for removing corneal reflected light of illumination light for photographing. This process can be executed with reference to an array of a plurality of bright spot images, for example. That is, in consideration of the arrangement of the LED groups 131-i and astigmatism, the plurality of bright spot images are arranged in a substantially circular shape. Therefore, by comparing with the position of the already specified bright spot image, it is possible to determine whether the spot specified as the bright spot image is truly a bright spot image or corneal reflected light.

  As described above, instead of automatically specifying the bright spot image, it is possible to display the astigmatism photographed image and manually designate the bright spot image.

  In addition, a case where bright spot images corresponding to all the LEDs 131-i cannot be specified (in the case of FIG. 3, a case where less than 36 bright spot images are specified) is also assumed. Considering this, it may be sufficient to specify a predetermined number or more of bright spot images, and the process may be shifted to the next process. In the next process, an approximate circle of the position of the specified bright spot image group is obtained. Mathematically, if any three points are specified, a circle passing through them can be obtained. On the other hand, in this embodiment, it is necessary to obtain the positional deviation of the bright spot image with respect to the perfect circle (that is, the positional deviation of the LED 131-i). Therefore, in order to calculate the positional deviation, for example, when four or more bright spot images are specified, the process can be shifted to the next process. Needless to say, it is desirable to specify as many bright spot images as possible in consideration of processing accuracy and accuracy.

  The position of the bright spot image may be a coordinate value in a two-dimensional coordinate system defined in advance in the frame of the astigmatism photographed image. In the subsequent processing, the absolute position of the bright spot image is not referred to, and the relative arrangement of multiple bright spot images is taken into consideration, so as long as the coordinate system is consistently applied to all bright spot images. Any coordinate system may be applied.

  Next, the bright spot image position information generation unit 81 obtains an approximate circle for the position of the specified bright spot image group. If the arrangement of the LEDs 131-i is along a perfect circle, an approximate circle that passes through all the bright spot images is obtained. However, as described above, since the positional deviation inevitably occurs when the LED 131-i is attached, it is rare that an approximate circle that passes through all the bright spot images is obtained.

  In general, an approximate circle is obtained such that the total amount of positional deviation with respect to the specified bright spot image group is minimized. In order to obtain such an approximate circle, for example, the least square method may be executed based on the positions of these bright spot images. When the least square method is executed with any one of the bright spot images as a reference, if the positional deviation of the bright spot image is large, the accuracy of the approximate circle may be deteriorated due to the influence of the positional deviation. In order to solve this problem, it is possible to obtain an approximate circle sequentially with reference to several bright spot images, and to adopt an approximate circle having the smallest total amount of positional deviation among them. Here, the number of bright spot images used as a reference can be set small when the processing time or the like is important, and can be set large when the accuracy is important.

  The method for obtaining the approximate circle is not limited to the above, and any known method can be applied. The approximate circle obtained by this processing is used as the “perfect circle” of the present invention. The bright spot image position information generation unit 81 is an example of the “roundness calculation means” of the present invention.

  Subsequently, the bright spot image position information generation unit 81 obtains the displacement of each bright spot image with respect to the obtained approximate circle. This process is executed, for example, by calculating the distance between each bright spot image and the approximate circle. The displacement for calculation purpose is information including the calculated distance and the direction of the bright spot image with respect to the approximate circle. The displacement obtained for each bright spot image is collectively used as bright spot image position information 71.

  Another method is as follows. First, one bright spot image is used as a reference. As this reference bright spot image, for example, an image having the shortest distance to the approximate circle is selected. Next, a position (reference position) on the approximate circle corresponding to the reference bright spot image is determined. If the reference bright spot image is on the approximate circle, that position is taken as the reference position. On the other hand, when the reference bright spot image is not on the approximate circle, the distance between the reference bright spot image and the approximate circle is obtained, and the intersection of the line segment along the distance direction and the approximate circle is set as the reference position. The reference position setting method is not limited to this.

  Subsequently, the approximate circle is divided into a predetermined number of arcs starting from the reference position. This predetermined number is the number of LEDs 131-i. In the case shown in FIG. 3, the approximate circle is divided into 36 equal parts. Thereby, a predetermined number of points (reference points) are set on the approximate circle. In the case of FIG. 3, 36 points are set.

  Next, a bright spot image corresponding to each reference point is selected. This process can be executed, for example, by selecting the bright spot image closest to each reference point. The positional deviation of the LED 131-i is not so large, and considering that it is astigmatism, there is a high possibility that a bright spot image is uniquely specified for each reference point.

  However, it cannot be said that two or more bright spot image candidates are not specified for each reference point. In that case, for example, the relative positions of these bright spot images can be referred to. That is, it is possible to order a plurality of bright spot images clockwise (or counterclockwise) starting from the reference bright spot image. Similarly, the reference points can be ordered clockwise (or counterclockwise) starting from the reference position. Based on these orders, it is possible to associate the bright spot image with the reference point. Note that this method may be used from the beginning to select a bright spot image corresponding to each reference point.

  In addition, when only luminescent spot images smaller than the number of LEDs 131-i are extracted, the luminescent spot images cannot be associated with all the reference points. In this case, for example, a reference point located at the shortest distance with respect to each bright spot image may be selected.

  Next, the displacement of the bright spot image with respect to the reference point is obtained for each pair of the reference point and bright spot image that are associated with each other. This displacement includes the distance between the reference point and the bright spot image and the direction of the bright spot image with respect to the reference point. And the displacement calculated | required about each pair is collectively made into the bright spot image position information 71. FIG. This is the end of the description of the bright spot image position information generation unit 81.

(Calculation processing part)
The arithmetic processing unit 80 executes various arithmetic processes. In particular, the calculation processing unit 80 functions as an example of the “calculation unit” of the present invention, and calculates an evaluation value of the corneal shape of the eye to be examined. As this evaluation value, there are a corneal curvature radius, a corneal refractive power, a corneal astigmatism, a corneal astigmatism axis angle, and the like, as in the past. The arithmetic processing unit 80 includes a microprocessor or the like that can execute a target arithmetic processing.

  The arithmetic processing unit 80 includes a bright spot image position information generation unit 81, a light source identification unit 82, a bright spot image selection unit 83, a mounting direction displacement calculation unit 84, a bright spot image correspondence unit 85, a bright spot image position correction unit 86, and An evaluation value calculation unit 87 is provided. The bright spot image position information generation unit 81 has been described above.

(Light source identification part)
The light source specifying unit 82 specifies the LED 131-i arranged at a position corresponding to the astigmatic axis direction of the patient's eye E. As the astigmatic axis direction, a value calculated by an evaluation value calculation unit 87 described later is used. In addition, you may make it use the value of the astigmatic axis direction of the patient's eye E acquired by the past test | inspection. The position corresponding to the astigmatic axis direction is the arrangement of the main meridian direction (strong main meridian direction or weak main meridian direction) of the cornea of the patient's eye E and the main meridian of the toric IOL (strong main meridian or weak main meridian). Direction. The light source identification unit 82 is an example of the “light source identification unit” of the present invention.

  An example of processing executed by the light source identification unit 82 will be described. The astigmatic axis direction is known. The astigmatic axis direction is obtained in units of 10 degrees or 5 degrees, for example. In the example shown in FIG. 3, when the astigmatic axis direction is obtained in units of 10 degrees, a pair of LEDs 131-i and 131- (i + 18) positioned to face each other along the astigmatic axis direction are specified.

  On the other hand, when the astigmatic axis direction is obtained in units of 5 degrees, there are cases where a pair of LEDs 131-i and 131- (i + 18) arranged opposite to each other are specified, and other cases. In the former case, for example, the angle shown in the astigmatic axis direction is a multiple of 10. The latter case is, for example, a case where the angle shown in the astigmatic axis direction is a multiple of 5 and not a multiple of 10. In the latter case, for example, two pairs of LEDs 131-i, 131- (i + 18), 131- (i + 1), and 131- (i + 19) that are opposed to each other and sandwich the astigmatic axis direction are specified. To do.

  The LED control unit 61 changes the lighting state of the identified LED 131-i. This process has been described above.

(Bright spot image selector)
A series of processing is executed in cooperation from the bright spot image selection unit 83 to the evaluation value calculation unit 87. This series of processing is processing for calculating an evaluation value of the shape of the cornea of the patient's eye E. In particular, the process from the bright spot image selecting unit 83 to the bright spot image corresponding unit 85 is performed in consideration of the mounting direction of the head unit 131 in which the LED group 131-i is arranged.

  When considering the mounting direction of the head unit 131, as described above, both when acquiring an astigmatism captured image and when acquiring a captured image of the cornea of the patient's eye E (corneal captured image), The control of the lighting state of the specific LED 131-n in the LED group 131-i is controlled, and the bright spot image of the specific LED 131-n can be identified.

  The bright spot image selection unit 83 selects a bright spot image corresponding to the specific LED 131-n from all the bright spot images based on the difference in lighting state between the specific LED 131-n and the other LEDs 131-i. To do. The bright spot image selection unit 83 is an example of the “selection unit” in the present invention.

  Processing executed by the bright spot image selection unit 83 will be described. As described above, as examples of different lighting states, (1) blink a specific LED 131-n, (2) change the color of the output light, (3) change the brightness of the output light, (4) bright Such as changing the size of a point.

  (1) When a specific LED 131-n is blinked, a moving image is acquired as an astigmatism image and a cornea image. It suffices that the moving image capturing time is longer than the blinking interval of the specific LED 131-n. The bright spot image selection unit 83 selects a bright spot image corresponding to a specific LED 131-n based on the temporal change of the pixel values of the pixels constituting the moving image. At this time, by referring to the blinking interval, a pixel whose pixel value changes in the same cycle may be specified.

  In addition, a still image is acquired at the timing when the light is extinguished while blinking, and pixels corresponding to dark luminescent spots (when taken at a timing when they are not completely extinguished) and luminescent spots that should be detected are detected. It is configured to search for a pixel corresponding to a position that is not performed (when it is photographed at a timing when it is completely extinguished), and to select the position of the pixel as a (light position) corresponding to a specific LED 131-n. May be.

  (2) When changing the color of the output light, the astigmatism photographed image or the cornea photographed image may be a moving image or a still image. The target image is preferably a color image, but may be a monochrome image. It is desirable to apply a monochrome image when an output color having a clearly different luminance value is set.

  When the target image is a color image, the bright spot image selection unit 83 identifies the color represented by the pixel with reference to pixel values (R value, G value, B value) of the pixel constituting the target image, Based on the result, a bright spot image corresponding to the specific LED 131-n is selected. When the target image is a monochrome image, the bright spot image selection unit 83 identifies the color represented by the pixel based on the luminance value of the pixel constituting the target image, and determines the specific LED 131-n based on the result. Select the corresponding bright spot image.

(Mounting direction displacement calculator)
The mounting direction displacement calculation unit 84 includes the positional information of the bright spot image (non-astigmatic specific bright spot image) corresponding to the specific LED 131-n in the astigmatism photographed image and the brightness corresponding to the specific LED 131-n in the cornea photographed image. The position information of the point image (corneal specific bright point image) is acquired from the bright point image selection unit 83.

  These position information represents, for example, the relative position of the specific bright spot image with respect to a predetermined position in the image. As an example, the direction of the specific bright spot image with respect to the center of the approximate circle described above (for example, an angle with respect to a predetermined direction) can be used as position information.

  The mounting direction displacement calculation unit 84 compares the position information of the astigmatism specific luminescent spot image with the position information of the cornea specific luminescent spot image, and between the shooting of the astigmatism shooting image and the shooting of the cornea shooting image. The displacement in the mounting direction of the projection image forming unit 13 (light source holding means) is obtained. The mounting direction displacement calculating unit 84 is an example of the “mounting direction displacement calculating unit” of the present invention.

An example of processing executed by the mounting direction displacement calculation unit 84 will be described. When the position information is the above angle, the angle shown in the position information of the astigmatic specific bright spot image is θ ₀ , and the angle shown in the position information of the cornea specific bright spot image is θ. These angles θ ₀ and θ are angles with respect to the same direction (for example, upward) in both images.

The mounting direction displacement calculator 84 calculates the displacements Δθ = θ−θ ₀ of these angles θ ₀ and θ. The displacement Δθ represents the deviation of the angle θ on the corneal specific luminescent spot image side from the angle θ ₀ on the astigmatic specific luminescent spot image side. Instead of this, the displacement of the angle θ ₀ on the astigmatic specific bright spot image side with respect to the angle θ on the cornea specific bright spot image side may be calculated.

(Bright spot image corresponding part)
The bright spot image corresponding unit 85 acquires information on the displacement (Δθ) calculated by the mounting direction displacement calculating unit 84. Based on the displacement Δθ, the bright spot image correspondence unit 85 associates the bright spot image position information 71 with a plurality of bright spot images indicating the position and a plurality of bright spot images in the cornea image. Here, the plurality of bright spot images whose positions are indicated in the bright spot image position information 71 mean a plurality of bright spot images specified from the astigmatism photographed image. The bright spot image correspondence unit 85 is an example of the “bright spot image correspondence unit” of the present invention.

  An example of processing executed by the bright spot image corresponding unit 85 will be described. First, a case where the same number of bright spot images as the LED group 131-i is obtained for both images will be described (in the example of FIG. 3, when 36 bright spot images are specified from both images). is there).

  In this case, the bright spot image corresponding unit 85 rotates the cornea image by −Δθ so that the displacement Δθ is eliminated. The rotation center at this time is the center of the approximate circle obtained for the cornea image. Thereby, the direction of the cornea specific bright spot image in the cornea photographed image coincides with the direction of the astigmatic specific bright spot image in the astigmatism photographed image.

  Subsequently, the bright spot image correspondence unit 85 associates the cornea specific bright spot image with the astigmatic specific bright spot image, and further sequentially associates both bright spot images clockwise (or counterclockwise). To go. Thereby, the plurality of bright spot images in the astigmatism photographed image are associated with the plurality of bright spot images in the cornea photographed image.

  A case will be described in which only a smaller number of bright spot images than the LED group 131-i were obtained for one or both images. Also in this case, the cornea image is rotated by −Δθ so that the direction of the corneal specific bright spot image coincides with the direction of the astigmatic specific bright spot image.

  Subsequently, the bright spot image correspondence unit 85 associates the cornea specific bright spot image with the astigmatic specific bright spot image, and further sequentially associates both bright spot images clockwise (or counterclockwise). To go. At this time, a bright spot image is generated in which the correspondence destination is not found although the correspondence is performed for each predetermined angle (the interval between the LED groups 131-i. 10 degrees, 5 degrees, etc.).

  The positional deviation of the LED 131-i, that is, the positional deviation of the bright spot image is sufficiently smaller than the predetermined angle. Further, the positional deviation in the radial direction of the approximate circle is not so large. Therefore, it is unlikely that two or more correspondence destinations of a certain bright spot image are candidates. Considering this, a bright spot image for which no corresponding destination is found can be ignored.

  As another method, the position on the approximate circle on the other image side can be associated with the bright spot image for which no correspondence destination is found. As the position on the approximate circle, a position where the corresponding bright spot image should originally exist (such as a position obtained by dividing the approximate circle into arcs) is adopted. When this method is applied, the position on the approximate circle is regarded as the position of the bright spot image in the subsequent processing.

(Bright spot image position correction unit)
The bright spot image position correction unit 86 corrects the positions of a plurality of bright spot images depicted in the cornea image based on the bright spot image position information 71. The bright spot image position correcting unit 86 constitutes an example of the “correcting unit” of the present invention.

  An example of processing executed by the bright spot image position correction unit 86 will be described. As described above, the bright spot image position information 71 records displacements of a plurality of bright spot images in the astigmatism captured image with respect to a perfect circle. Further, the bright spot image correspondence unit 85 associates a plurality of bright spot images in the cornea shot image and a plurality of bright spot images in the astigmatism shot image.

The bright spot image position correction unit 86 selects, from the bright spot image position information 71, the displacement of the bright spot image in the astigmatism shot image associated with each bright spot image in the cornea shot image. Furthermore, the luminescent spot image position correction unit 86, so as to cancel the selected displaced, changing the position of the bright spot image in the cornea imaging image. Changing the position of the bright spot image so as to cancel the displacement means moving the bright spot image by an inverse vector of the displacement.

  In this process, it is not necessary to actually move the position of the bright spot image in the cornea image. The position of each bright spot image is expressed by a two-dimensional coordinate system defined in the cornea image. Therefore, in the above process, it is sufficient to change the coordinate value of each bright spot image by the corresponding inverse vector of the displacement. The bright spot image position correction unit 86 performs the above processing on each of the plurality of bright spot images in the cornea image.

(Evaluation value calculator)
The evaluation value calculation unit 87 calculates an evaluation value of the shape of the cornea of the patient's eye E based on the plurality of bright spot images whose positions have been corrected by the bright spot image position correction unit 86. As described above, the evaluation value includes a corneal curvature radius, corneal refractive power, corneal astigmatism, corneal astigmatism axis angle, and the like. The calculation method of these evaluation values is the same as that of the conventional keratometer.

(Operation section)
The operation unit 90 is used by an operator or the like to operate the microscope 1 for ophthalmic surgery. The operation unit 90 includes various hardware keys (buttons, switches, etc.) provided on the housing of the microscope 6 and the foot switch 8. When a touch panel display is provided, the operation unit 90 includes various software keys displayed on the touch panel display.

[Action / Effect]
The operation and effect of the microscope for ophthalmologic surgery 1 will be described.

  First, the microscope for ophthalmologic surgery 1 generates bright spot image position information 71 as a preparation stage. The contents of this process have been described above. This process can be performed at an arbitrary timing before using the function according to this embodiment. For example, this process can be performed when the microscope 1 for ophthalmic surgery is manufactured, before shipment, or when installed in an operating room. Further, when there is a possibility that the position of the LED group 131-i changes as the microscope for ophthalmic surgery 1 is used, the bright spot image position information 71 may be updated as appropriate. The generated bright spot image position information 71 is stored in the storage unit 70.

  The following steps are performed during surgery. First, the microscope for ophthalmologic surgery 1 photographs the cornea of the patient's eye E in a state where a plurality of bright spots are projected by the LED 131-i.

  Further, the microscope for ophthalmologic surgery 1 corrects the positions of a plurality of bright spot images depicted in the cornea image based on the bright spot image position information 71. In this process, for example, the position of each bright spot image in the cornea shot image is corrected so as to cancel the displacement of each bright spot image in the astigmatism shot image indicated by the bright spot image position information 71.

  Then, the microscope for ophthalmologic surgery 1 calculates the evaluation value of the corneal shape of the patient's eye E based on the corrected positions of the plurality of bright spot images. This evaluation value includes the corneal curvature radius, corneal refractive power, corneal astigmatism, corneal astigmatism axis angle, and the like.

  As described above, the microscope for ophthalmologic surgery 1 changes the position of the luminescent spot image in the cornea image using the positional deviation of the luminescent spot image (bright spot image position information 71) in the astigmatic state. It comes to ask for. Therefore, the evaluation value can be obtained by eliminating the influence of the displacement of the mounting position of the LED 131-i. That is, according to the microscope 1 for ophthalmic surgery, it is possible to accurately measure the shape of the cornea even when a plurality of bright spots projected on the cornea are not arranged in a perfect circle.

  Further, the microscope for ophthalmologic surgery 1 controls a specific LED 131-n in the LED group 131-i to be in a lighting state different from that of the other LED group 131-i (i ≠ n). Thereby, the bright spot image corresponding to the specific LED 131-n is observed in a different form from the bright spot images corresponding to the other LED groups 131-i on the observation target (astigmatic corneal model eye, patient eye E). The In this state, an astigmatism image and a cornea image are acquired.

  The microscope for ophthalmologic surgery 1 selects a bright spot image corresponding to a specific LED 131-n from a plurality of bright spot images based on the lighting state of each LED 131-i.

  Further, the microscope 1 for ophthalmic surgery uses the position of the bright spot image (corresponding to the specific LED 131-n) selected for the astigmatism captured image and the bright spot image (specific LED 131- selected) for the cornea captured image. and the position in the mounting direction of the projection image forming unit 13 between the time of shooting the astigmatism image and the time of shooting the cornea image.

  Then, based on the displacement in the mounting direction of the projection image forming unit 13, the ophthalmic surgical microscope 1 uses a plurality of bright spot images (that is, bright spots in the astigmatism photographed image) indicating the positions in the bright spot image position information 71. Image) and a plurality of bright spot images in the cornea image. In this association, as described above, a bright spot image that is not associated may remain.

  According to such a configuration, even when the mounting direction of the projection image forming unit 13 is different between the acquisition of the astigmatism captured image and the acquisition of the cornea captured image, the bright spot image corresponding to the specific LED 131-n is obtained. By referencing, it is possible to accurately associate the bright spot image in the astigmatism photographed image with the bright spot image in the cornea photographed image.

  In general, in an ophthalmic surgical microscope, the attachment position of an assistant's microscope and a slit illumination device can be changed. Thereby, the attachment position of the projection image forming unit 13 may be changed. If it does so, direction of LED group 131-i will change, the state of displacement of LED group 131-i with respect to a perfect circle will change, and as a result, the reproducibility of evaluation value calculation will fall. On the other hand, according to this configuration, the bright spot image in the astigmatism photographed image and the bright spot image in the cornea photographed image can be accurately associated with each other, so that such a problem does not occur.

  When the astigmatic axis direction of the cornea of the patient's eye E is calculated as the evaluation value, the microscope for ophthalmic surgery 1 selects the LED 131-m arranged at a position corresponding to the astigmatic axis direction from the LED group 131-i. The lighting state of this LED 131-m is changed.

  Thereby, it is possible to present the direction of the astigmatic axis of the patient's eye E to the operator or the like, for example, in a toric IOL transplantation operation. In particular, since the astigmatic axis direction obtained in this embodiment has high accuracy, it is expected to improve the surgical accuracy.

[Modification]
What has been described above is merely an example of the configuration for carrying out the present invention. Those who intend to implement the present invention can make appropriate modifications within the scope of the present invention.

  A configuration for accurately associating the bright spot image in the astigmatism photographed image with the bright spot image in the cornea photographed image by a method different from the above embodiment will be described.

  The microscope for ophthalmic surgery according to this modification includes a sensor that detects the mounting direction of the projection image forming unit 13 (light source holding unit) with respect to the microscope 6 (device housing). This sensor is an example of the “detecting means” of the present invention.

  A specific example of the sensor will be described. A sensor is provided at each mounting position of the light source holding means with respect to the microscope 6. When the light source holding means is mounted at a certain mounting position, a sensor at the mounting position detects the mounting. The configuration of the sensor is not limited to this, and the specific configuration is not limited as long as the mounting direction of the light source holding unit with respect to the apparatus housing can be detected.

  This microscope for ophthalmologic surgery has a control system similar to that of the above embodiment (see FIG. 6). However, the bright spot image selection unit 83 is not necessary. Hereinafter, a description will be given with reference to FIG. Information indicating the mounting direction detected by the sensor is stored in the storage unit 70. In particular, the storage unit 70 stores information (reference mounting direction information) indicating the mounting direction (reference mounting direction) at the time of shooting an astigmatism captured image.

  When the light source holding means is attached in the operation of the patient's eye E, the sensor inputs a detection signal to the control unit 60. The control unit 60 specifies the current mounting direction based on the detection signal. When a sensor is provided at each mounting position, the control unit 60 specifies the current mounting direction according to which sensor has received the detection signal. In order to execute this process, table information that associates each sensor with the mounting direction may be stored in advance. The control unit 60 reads the reference mounting direction information from the storage unit 70 and sends it to the arithmetic processing unit 80 together with information indicating the current mounting direction (current mounting direction information).

  The mounting direction displacement calculation unit 84 calculates the displacement in the mounting direction by a process different from the above embodiment. That is, the mounting direction displacement calculation unit 84 calculates the displacement between the reference mounting direction and the current mounting direction, so that the mounting direction when shooting the astigmatism image and the mounting direction when shooting the cornea image. Find the displacement between. Here, the mounting direction is expressed as, for example, an angle in a counterclockwise direction with a predetermined direction (operator side or the like) as a reference (0 degree). The mounting direction displacement calculating unit 84 is an example of the “mounting direction displacement calculating unit” of the present invention.

  The bright spot image corresponding unit 85 receives the calculation result of the displacement in the mounting direction from the mounting direction displacement calculation unit 84. Based on the displacement in the mounting direction, the bright spot image correspondence unit 85 associates the bright spot image position information 71 with a plurality of bright spot images indicating the position and a plurality of bright spot images in the cornea image. This process can be executed in the same manner as in the above embodiment. The bright spot image correspondence unit 85 is an example of the “bright spot image correspondence unit” of the present invention.

  The bright spot image position correction unit 86 and the evaluation value calculation unit 87 operate in the same manner as in the above embodiment, and calculate the evaluation value of the corneal shape of the patient's eye E.

  According to the microscope for ophthalmic surgery according to this modified example, even if the mounting direction of the light source holding means is different between the shooting of the astigmatism shooting image and the shooting of the cornea shooting image, the mounting direction at each shooting is detected. By taking the displacement into account, the bright spot image in the astigmatism photographed image can be accurately associated with the bright spot image in the cornea photographed image. Thereby, the problem that the reproducibility of evaluation value calculation is reduced is avoided.

  Another modification will be described. Some ophthalmologic apparatuses are configured so that an eye to be examined can be observed with binocular eyes. The above-mentioned ophthalmic surgical microscope 1 is an example thereof (see particularly FIG. 5). The observation optical system of such an ophthalmologic apparatus is provided with a pair of left and right optical systems having a common objective lens. That is, in such an ophthalmologic apparatus, the reflected light of the illumination light from the eye to be examined enters the left and right optical systems via the objective lens and is guided to the left and right eyepieces, respectively. The examiner looks through the left and right eyepieces with the left and right eyes and observes with binocular eyes.

  An ophthalmologic apparatus in which the objective lens and the left and right optical systems are decentered, that is, the optical axis of the objective lens (objective optical axis) and the axis of the left and right optical system (observation optical axis) are displaced. In the ophthalmologic apparatus, the light beam that has passed near the edge of the objective lens enters the left and right optical systems (see FIG. 5). The cross-sectional shape of the light beam incident on the left and right optical systems changes due to the prism effect or the like at the passage site (near the edge). For example, when a light beam having a perfectly circular cross section is incident on the objective lens, a light beam having a substantially elliptical cross section is incident on the left and right optical systems due to the influence of the objective lens.

  When a projection unit and an imaging unit are mounted on such an ophthalmologic apparatus and the corneal shape is evaluated, an error occurs due to the influence of the objective lens. That is, the corneal reflection light of the plurality of bright spot images projected onto the cornea by the projection unit is projected onto the imaging unit with a shift in the arrangement state due to the influence of the objective lens. Therefore, the arrangement of the plurality of bright spot images depicted in the photographed image does not accurately reflect the corneal shape, resulting in an error in the evaluation value. This error is recognized as astigmatism.

  The modifications described below are for solving such problems. By adding the configuration of this modified example to the above-described embodiment, the corneal shape can be measured more accurately. It is possible to configure an ophthalmologic apparatus that does not include the features of the above-described embodiment and that includes the features of this modification.

  A description will be given with reference to the microscope for ophthalmic surgery 1 of the above embodiment. As shown in FIG. 5, a beam splitter 32 is provided in the right observation optical system 30R. The beam splitter 32 separates a part of the observation light guided along the observation optical axis OR through the objective lens 15 and guides it to the TV camera 56 (imaging means). In this modification, the photographing means is provided in only one of the left and right optical systems, but the photographing means may be provided in both optical systems.

  The control system of this modification is almost the same as that of the above embodiment. An example of the control system is shown in FIG. The main difference between this modification and the above embodiment is that the light flux image position information 72 is stored in the storage unit 70 and the operation content of the arithmetic processing unit 80.

  The luminous flux image position information 72 is created in advance and stored in the storage unit 70. An example of a method for creating the light flux image position information 72 will be described. First, a light beam having a substantially circular beam cross section is irradiated toward the objective lens 15 from below the objective lens 15 (side where the patient's eye E is disposed). This light beam has a substantially elliptical cross section via the objective lens 15 and is incident on the left and right observation optical systems 30L and 30R. The light beam incident on the right observation optical system 30 </ b> R is split by the beam splitter 32 into a light beam traveling toward the eyepiece lens 37 and a light beam traveling toward the TV camera 56. The TV camera 56 detects a light beam branched from the observation optical axis OR. Thereby, a photographed image of this light beam is obtained.

  The arithmetic processing unit 80 analyzes the captured image and creates light beam image position information 72. In this analysis processing, the displacement of the light beam image with respect to a perfect circle is obtained as information indicating the position of the light beam image (referred to as a light beam image) depicted in the photographed image. This process will be described in more detail.

  First, the arithmetic processing unit 80 obtains an ellipse (approximate ellipse) that optimally approximates the luminous flux image. This process can be executed by applying, for example, the least square method. Next, the arithmetic processing unit 80 obtains information representing the shape of the approximate ellipse, that is, the displacement with respect to the perfect circle. This information uniquely identifies the shape of the ellipse from various parameters related to the ellipse (major axis / minor axis, ellipticity (ratio of minor axis to major axis), major axis (minor axis) orientation, eccentricity, etc.). These are pre-selected as expressible parameters. Note that the orientation of the long axis and the short axis can be defined based on, for example, a two-dimensional coordinate system (orthogonal coordinate system or the like) set in advance on the light receiving surface of the imaging element of the TV camera 56.

  The control unit 60 stores the information obtained by the arithmetic processing unit 80 in the storage unit 70 as the luminous flux image position information 72.

  The substantially circular light beam used for creating the light beam image position information 72 is, for example, a light beam whose cross section is a ring shape or a disk shape. In the latter case, for example, the approximate ellipse is calculated after the contour extraction of the light flux image in the photographed image is executed. It is also possible to use a light beam group composed of a plurality of bright spots arranged in a substantially perfect circle as the substantially perfect light beam. In this case, the arrangement shape of a plurality of light beam images corresponding to the light beam group may be obtained in the same manner as in the above embodiment. Information indicating the displacement of each point on the approximate ellipse with respect to the perfect circle may be used as the light beam image position information 72. Information indicating the displacement of a perfect circle with respect to the approximate ellipse may be used as the light beam image position information 72.

  Further, the light flux image position information 72 may be image data of a photographic image in which the light flux image is depicted, a parameter that can uniquely express the shape of the light flux image, or the like. In these cases, the above processing is only executed later (for example, when analyzing a cornea image), so that information indicating the displacement of the light beam image with respect to a perfect circle is set as the light beam image position information 72. There is no substantial difference.

  As can be seen from the creation method described above, the bright spot image position information 71 is created for each projection unit, and the luminous flux image position information 72 is created for each ophthalmologic apparatus.

  The TV camera 56 images the cornea of the patient's eye E in a state where a plurality of bright spots are projected by the LED 131-i group. The arithmetic processing unit 80 (particularly the bright spot image position correcting unit 86), as in the above-described embodiment, uses the bright spot image position information 71 and the luminous flux image position as the positions of a plurality of bright spot images depicted in this cornea image. Correction is performed based on the information 72. The correction based on the bright spot image position information 71 is the same as in the above embodiment.

  The correction based on the light flux image position information 72 will be described. The bright spot image position correction unit 86 reflects the displacement recorded in the luminous flux image position information 72 on the position of each bright spot image after correction using the bright spot image position information 71, thereby each bright spot image. Correct the position of. For example, when the displacement of the approximate ellipse with respect to the perfect circle is recorded in the light beam image position information 72, the bright spot image position correction unit 86, for each bright spot image, the bright spot image corresponding to the inverse vector of the corresponding displacement. Shift the position of. That is, the bright spot image position correcting unit 86 corrects the positions of the plurality of bright spot images in the cornea image so as to cancel the displacement.

  Further, when the displacement of the perfect circle with respect to the approximate ellipse is recorded, the bright spot image position correcting unit 86 shifts the position of the bright spot image by a displacement corresponding to the bright spot image. Further, when the above parameters are recorded, the bright spot image position correction unit 86 deforms the arrangement of the bright spot images using the inverse value of this parameter.

  Then, the arithmetic processing unit 80 calculates an evaluation value of the corneal shape of the patient's eye E based on the positions of the plurality of bright spot images after both corrections are performed. This evaluation value includes the corneal curvature radius, corneal refractive power, corneal astigmatism, corneal astigmatism axis angle, and the like.

  Note that the correction based on the luminous flux image position information 72 may be performed before the correction based on the bright spot image position information 71 is performed. Further, the position of the bright spot image group may be corrected using a parameter (or displacement) obtained by combining both correction parameters (or displacement).

  According to this modification, in an ophthalmologic apparatus capable of binocular observation, not only an error in the evaluation value of the corneal shape due to the position of the LED group 131-i but also a displacement between the objective optical axis and the observation optical axis. Errors can also be automatically corrected. Therefore, even when a plurality of bright spots projected on the cornea are not arranged in a perfect circle, the corneal shape can be accurately measured.

  As described above, it is possible to configure an ophthalmologic apparatus that does not include the features of the above-described embodiment and that includes the features of this modification. The ophthalmologic apparatus includes an objective lens, an illumination optical system, an observation optical system, a projection unit, a photographing unit, a calculation unit, and a storage unit. The illumination optical system irradiates the eye to be examined with illumination light through the objective lens. The observation optical system has left and right optical systems that guide reflected light of illumination light from the eye to be examined via the objective lens to the left and right eyepieces via the zoom lens system. The projection means projects a plurality of bright spots arranged in a substantially circular shape onto the cornea of the eye to be examined. The imaging unit images the cornea in a state where a plurality of bright spots are projected. The calculation means calculates an evaluation value of the shape of the cornea based on the positions of the plurality of bright spot images depicted in the photographed image. The storage means stores in advance light beam image position information indicating the position of the image of the light beam depicted in the image taken by the photographing means of the substantially circular light beam incident on the objective lens.

  Furthermore, this ophthalmic apparatus has the following features. First, the optical axes of the left and right optical systems of the observation optical system are displaced with respect to the optical axis of the objective lens. Furthermore, one of the left and right optical systems includes a beam splitter that divides the reflected light of the illumination light from the eye to be examined into a light beam directed to the eyepiece lens and a light beam directed to the imaging means. Then, the calculation means calculates the position of the plurality of bright spot images depicted in the cornea photographed image obtained by photographing the cornea of the eye to be examined with the plurality of bright spots projected by the photographing means, and the light flux image position. Correction is performed based on the information, and furthermore, an evaluation value of the shape of the cornea is calculated based on the positions of the corrected images of the bright spots.

  According to this ophthalmologic apparatus, in an ophthalmologic apparatus capable of binocular observation, an error in the evaluation value of the corneal shape caused by the displacement between the objective optical axis and the observation optical axis can be automatically corrected. It is possible to improve the accuracy of measurement.

1 Microscope for ophthalmic surgery (ophthalmic device)
13 Projection Image Forming Unit 131 Head 131-i LED (Group)
132 Head connection unit 133 Arm 134 Drop prevention unit 15 Objective lens 20 Illumination optical system 30 Observation optical system 32 Beam splitter 56 TV camera 60 Control unit 61 LED control unit 70 Storage unit 71 Bright spot image position information 72 Luminous beam image position information 80 Calculation Processing unit 81 Bright spot image position information generation part 82 Light source identification part 83 Bright spot image selection part 84 Mounting direction displacement calculation part 85 Bright spot image correspondence part 86 Bright spot image position correction part 87 Evaluation value calculation part E Patient eye

Claims (9)

A projection means for projecting a plurality of bright spots arranged in a substantially circular shape onto the cornea of an eye to be examined, and an imaging means for photographing the cornea in a state in which the plurality of bright spots are projected, and depicted in the photographed image An ophthalmologic apparatus that calculates an evaluation value of the shape of the cornea based on the positions of the plurality of bright spot images,
Bright spot image position indicating positions of the plurality of bright spot images depicted in the astigmatism photographed image obtained by photographing the astigmatic cornea model eye with the plurality of bright spots projected by the photographing means Storage means for storing information in advance;
The position of the plurality of bright spot images described in the cornea photographed image obtained by photographing the cornea of the eye to be inspected with the plurality of bright spots projected by the photographing means, the bright spot image position information. And calculating means for calculating the evaluation value of the cornea based on the position of the image of the plurality of bright spots after the correction,
Equipped with a,
In the bright spot image position information, displacement of the plurality of bright spot images in the astigmatism photographed image with respect to a perfect circle is recorded,
The computing means is
Correction means for correcting the positions of the plurality of bright spot images in the cornea image so as to cancel the displacement;
A perfect circle calculation means for obtaining an approximate circle for the positions of the plurality of bright spot images as the perfect circle,
Calculating the evaluation value based on the position of the image after the correction;
Ophthalmic device comprising a call. The perfect circle calculation means obtains the approximate circle by applying a least square method to the positions of the images of the plurality of bright spots.
The ophthalmic apparatus according to claim 1 . A projection means for projecting a plurality of bright spots arranged in a substantially circular shape onto the cornea of an eye to be examined, and an imaging means for photographing the cornea in a state in which the plurality of bright spots are projected, and depicted in the photographed image An ophthalmologic apparatus that calculates an evaluation value of the shape of the cornea based on the positions of the plurality of bright spot images,
Bright spot image position indicating positions of the plurality of bright spot images depicted in the astigmatism photographed image obtained by photographing the astigmatic cornea model eye with the plurality of bright spots projected by the photographing means Storage means for storing information in advance;
The position of the plurality of bright spot images described in the cornea photographed image obtained by photographing the cornea of the eye to be inspected with the plurality of bright spots projected by the photographing means, the bright spot image position information. And calculating means for calculating the evaluation value of the cornea based on the position of the image of the plurality of bright spots after the correction,
With
The projection means includes
A plurality of light sources for projecting the plurality of bright spots are installed in a substantially circular shape, and a light source holding means detachable from the apparatus housing;
A light source control means for controlling a specific light source of the plurality of light sources to be in a lighting state different from other light sources;
Including
The computing means is
Selection means for selecting an image corresponding to the specific light source among the plurality of bright spot images based on the lighting state;
The position of the selected image with respect to the astigmatism photographed image is compared with the position of the selected image with respect to the cornea photographed image, and the photographing of the astigmatism photographed image and the photographing of the cornea photographed image are performed. A mounting direction displacement calculating means for obtaining a displacement in the mounting direction of the light source holding means between time;
Based on the obtained displacement in the mounting direction, the bright spot image position information is associated with the bright spot image indicating the position and the bright spot image in the cornea image. Point image correspondence means;
Including
Calculating the evaluation value based on the result of the association;
Ophthalmic device you wherein a. A projection means for projecting a plurality of bright spots arranged in a substantially circular shape onto the cornea of an eye to be examined, and an imaging means for photographing the cornea in a state in which the plurality of bright spots are projected, and depicted in the photographed image An ophthalmologic apparatus that calculates an evaluation value of the shape of the cornea based on the positions of the plurality of bright spot images,
Bright spot image position indicating positions of the plurality of bright spot images depicted in the astigmatism photographed image obtained by photographing the astigmatic cornea model eye with the plurality of bright spots projected by the photographing means Storage means for storing information in advance;
The position of the plurality of bright spot images described in the cornea photographed image obtained by photographing the cornea of the eye to be inspected with the plurality of bright spots projected by the photographing means, the bright spot image position information. And calculating means for calculating the evaluation value of the cornea based on the position of the image of the plurality of bright spots after the correction,
With
The projection means includes
A plurality of light sources for projecting the plurality of bright spots are installed in a substantially circular shape, and a light source holding means detachable from the apparatus housing;
Detecting means for detecting a mounting direction of the light source holding means with respect to the apparatus housing;
Including
The arithmetic means is a mounting direction displacement calculating means for obtaining a displacement between the detected mounting direction at the time of shooting the astigmatism captured image and the detected mounting direction at the time of capturing the cornea captured image;
Based on the obtained displacement in the mounting direction, the bright spot image position information is associated with the bright spot image indicating the position and the bright spot image in the cornea image. Point image correspondence means;
Including
Calculating the evaluation value based on the result of the association;
Ophthalmology equipment, characterized in that. An objective lens;
An illumination optical system that irradiates the eye with illumination light through the objective lens;
An observation optical system that guides the reflected light of the illumination light from the eye to be examined via the objective lens to an eyepiece through a zoom lens system;
With
The plurality of light sources are arranged at positions deviated from the optical path of the illumination light and the optical path of the reflected light between the objective lens and the eye to be examined.
The computing means is
Calculating the astigmatic axis direction of the cornea of the eye to be examined as the evaluation value,
A light source specifying means for specifying a light source arranged at a position corresponding to the calculated astigmatism axis direction from the plurality of light sources,
A lighting state changing means for changing the lighting state of the identified light source;
The ophthalmologic apparatus according to claim 3 or 4 , wherein the ophthalmologic apparatus is provided. The observation optical system has left and right optical systems that guide the reflected light that has passed through the objective lens to left and right eyepieces, respectively.
The optical axes of the left and right optical systems are displaced with respect to the optical axis of the objective lens,
One of the left and right optical systems includes a beam splitter that divides the reflected light into a light beam directed to the eyepiece lens and a light beam directed to the photographing means,
The storage means stores in advance light beam image position information indicating the position of the image of the light beam depicted in the image taken by the photographing means of the substantially circular light beam incident on the objective lens,
The calculation means corrects the positions of the plurality of bright spot images depicted in the cornea image based on the luminous flux image position information together with the bright spot image position information, and the corrected plurality of bright spots. Calculating the evaluation value based on the position of the image of
The ophthalmic apparatus according to claim 5 . In the light beam image position information, a displacement with respect to a perfect circle of the light beam image is recorded,
The calculation means corrects the positions of the plurality of bright spot images in the cornea image so as to cancel the displacement.
The ophthalmic apparatus according to claim 6 . An objective lens;
An illumination optical system that irradiates the eye with illumination light through the objective lens;
An observation optical system having left and right optical systems for guiding reflected light of the illumination light from the eye to be examined via the objective lens to left and right eyepieces via a zoom lens system;
Projecting means for projecting a plurality of bright spots arranged in a substantially circular shape onto the cornea of the eye to be examined,
Photographing means for photographing the cornea in a state where the plurality of bright spots are projected;
A computing means for calculating an evaluation value of the shape of the cornea based on the positions of the images of the plurality of bright spots depicted in the photographed image;
Storage means for preliminarily storing light beam image position information indicating the position of the image of the light beam depicted in the image taken by the photographing means of the substantially circular light beam incident on the objective lens;
With
The optical axes of the left and right optical systems are displaced with respect to the optical axis of the objective lens,
One of the left and right optical systems includes a beam splitter that divides the reflected light into a light beam directed to the eyepiece lens and a light beam directed to the photographing means,
The calculation means is configured to determine the positions of the images of the plurality of bright spots depicted in the cornea photographed image obtained by photographing the cornea of the eye to be examined in a state where the plurality of bright spots are projected by the photographing means. Correcting based on light beam image position information, and calculating the evaluation value of the cornea based on the position of the image of the plurality of bright spots after the correction,
An ophthalmic apparatus characterized by that. In the light beam image position information, a displacement with respect to a perfect circle of the light beam image is recorded,
The calculation means corrects the positions of the plurality of bright spot images in the cornea image so as to cancel the displacement.
The ophthalmic apparatus according to claim 8 .