JP2017086163A - Ophthalmologic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ophthalmologic measuring apparatus capable of smoothly performing alignment for an eye to be examined in a second and further examinations.SOLUTION: An ophthalmologic measuring apparatus includes, in a measurement unit, an anterior eye part observation optical system 50 having an image pickup device 52 for picking up a front image of an anterior eye part of an eye E to be examined, and a measurement optical system 10 having a measurement axis L1 for measuring the eye E to be examined. A control unit 100 of the ophthalmologic measuring apparatus acquires optometric position information indicating the position of the measurement axis with respect to the anterior eye part, which is the measurement position information indicating the position of an optometric axis when eye characteristics are examined using the measurement optical system 10. The control unit 100 displays a live image of the front image picked up by the image pickup device 52 on a monitor 70, and displays a previous position index indicating the position of the optometric axis in a previous examination in the anterior eye part on the live image based on the examination position information.SELECTED DRAWING: Figure 2

Description

  The present disclosure relates to an ophthalmologic apparatus for inspecting an eye to be examined.

  2. Description of the Related Art Conventionally, an ophthalmic apparatus for inspecting an eye to be examined has been proposed in which an optometric axis of the apparatus can be manually aligned with respect to an arbitrary position in the eye to be examined (see, for example, Patent Document 1). For example, in the device of Patent Document 1, when the position of the eye to be examined and the optometry axis of the device are adjusted to an arbitrary positional relationship by manual alignment, coordinate information indicating the three-dimensional position of the optometry portion with respect to the device is Displayed on the monitor.

JP-A-8-103414

  However, in the conventional apparatus, the alignment with respect to the eye to be examined in the second and subsequent examinations cannot be said to be smooth.

  The present disclosure has been made in view of the problems of the prior art, and an object thereof is to provide an ophthalmologic measurement apparatus that can smoothly perform alignment with respect to an eye to be examined in the second and subsequent examinations.

  An ophthalmologic apparatus according to a first aspect of the present disclosure includes an anterior ocular segment observation optical system having an imaging device that captures a front image of an anterior ocular segment of an eye to be examined, and an optometry for examining the eye to be examined having an optometry axis. An optometry unit having a system, and examination position information indicating a position of the optometry axis when the eye characteristics have been previously examined using the optometry system, the optometry position indicating the position of the optometry axis with respect to the anterior eye part An acquisition means for acquiring information, and a live position image of the front image captured by the image sensor on a monitor, and a previous position index indicating the position of the optometry axis in the previous examination at the anterior segment on the live image Display control means capable of displaying the information based on the inspection position information.

  An ophthalmologic apparatus according to a second aspect of the present disclosure includes an anterior ocular segment observation optical system having an imaging element that captures a front image of an anterior ocular segment of an eye to be examined, and an optometry for examining the eye to be examined having an optometry axis. An optometry unit having a system, a drive unit for adjusting the positional relationship of the optometry axis with respect to the eye to be examined, and measurement position information indicating the position of the optometry axis at which the eye characteristics were examined, than the current examination Acquisition means for acquiring optometry position information indicating the position of the optometry axis in the previous examination which is the examination on the previous day; and controlling the drive unit so that the optometry axis coincides with a reference position on the eye to be examined, and the measurement Alignment guiding means for performing an inspection in a state where the axis matches the reference position of the eye to be examined, and whether or not to re-inspect at the position of the optometric axis in the previous examination based on the examination result by the alignment guiding means Determination processing means for determining , Wherein the alignment guide means comprises a guide means for guiding the alignment of the eye axis with respect to the eye based on a determination result of said determination processing unit.

  According to the present disclosure, it is possible to smoothly perform alignment on the eye to be examined in the second and subsequent examinations.

It is a figure which shows the external appearance of an ophthalmic measurement apparatus. It is the schematic block diagram which showed the optical system which the measurement part of an ophthalmic measuring apparatus has, and the control system of an ophthalmic measuring apparatus. It is the figure which showed typically the observation image displayed on a monitor. It is a figure which shows on the observation image of the state by which the parameter | index which shows the position of the measurement axis | shaft from which the eye characteristic was measured before is shown. It is a figure which shows the example of a display different from FIG. It is a flowchart which shows the flow of a measurement in case measurement is performed anew from the last measurement. It is a flowchart which shows the flow of the measurement in an operation example different from FIG.

  Hereinafter, an ophthalmologic apparatus according to an embodiment of the present disclosure will be described with reference to the drawings. In the following embodiment, as an example of an ophthalmologic apparatus, an ophthalmologic measurement apparatus 1 that measures the eye characteristics of the eye E to be examined is illustrated. In the ophthalmologic measurement apparatus 1, the eye characteristics of the eye E to be examined are measured with respect to the measurement axis. Examples of eye characteristics in the present disclosure include eye refractive power, eye aberration, eye shape (more specifically, corneal curvature, etc.), eye dimensions (more specifically, axial length, etc.), and And intraocular pressure. The ophthalmologic measurement apparatus 1 measures at least one of these eye characteristics. In the following description, a case where an autorefractometer that measures refractive power is mainly applied as the ophthalmic measurement apparatus 1 will be described as a specific example.

  First, with reference to FIG. 1, an example of the external configuration of the ophthalmic measurement apparatus 1 is shown. The ophthalmologic measurement apparatus 1 shown in FIG. 1 is a so-called stationary apparatus. The ophthalmic measurement apparatus 1 mainly includes a measurement unit 8. Although details will be described later, the measurement unit 8 is provided with at least an optical system used when measuring the eye characteristics. Note that the ophthalmic measurement device 1 may be a hand-held device.

  In the example of FIG. 1, the ophthalmologic measurement apparatus 1 further includes a base 2, a face support unit 4, a moving base 6, a drive unit 7, a joystick 9, and a monitor 70.

  The movable table 6 is supported by the base 2. The movable table 6 is moved on the base 2 in the vertical direction (Y direction) and the front-back direction (Z direction) by operating the joystick 9. A face support unit 4 is fixed to the base 2. As shown in FIG. 1, the face support unit 4 is used to support the face of the subject in a state where the eye E is opposed to the measurement unit 8. The drive unit 7 moves the measurement unit 8 in the left-right direction (X direction), the up-down direction (Y direction), and the front-back direction (Z direction) with respect to the eye E. When the examiner rotates the rotary knob 9 a provided on the joystick 9, the measuring unit 8 is moved in the Y direction by the driving unit 7. A switch 9b is provided on the top of the joystick 9. The monitor 70 displays various information such as an observation image of the eye E taken by the measurement unit 8 and a measurement result of the eye E by the measurement unit 8.

  Next, with reference to FIG. 2, the optical system which the measurement part 8 of the ophthalmic measurement apparatus 1 has is demonstrated. The measurement unit 8 mainly includes a measurement optical system 10 and an observation optical system (imaging optical system) 50. 2 includes a fixation target presentation optical system 30, a ring index projection optical system 45, and a working distance index projection optical system 46.

  The measurement optical system 10 is used to measure the eye characteristics of the eye E with respect to the measurement axis (“inspection axis” in the present embodiment). In the measurement optical system 10 shown in FIG. 2, the measurement axis is the optical axis indicated by L1. The measurement optical system 10 irradiates (projects) light toward the eye E, and receives reflected light from the eye E with a detector (for example, a light receiving element, an imaging element). Then, the eye characteristic of the eye E is acquired by processing the signal from the detector.

  The measurement optical system 10 shown in FIG. 2 is used for measuring eye refractive power as an eye characteristic. The measurement optical system 10 shown in FIG. 2 includes a light projecting optical system 10a and a light receiving optical system 10b. The light projecting optical system 10a projects a spot-like light beam onto the fundus Er of the eye E through the pupil of the eye E. The light receiving optical system 10b takes out the fundus reflection light in a ring shape through the periphery of the pupil, and generates a ring-like fundus reflection image mainly used for measuring the eye refractive power as a two-dimensional image pickup device 22 (of the detector). Take an example).

  In the example of FIG. 2, the light projecting optical system 10 a includes a measurement light source 11, a relay lens 12, a hall mirror 13, and an objective lens 14. The light receiving optical system 10b shares the hole mirror 13 and the objective lens 14 with the light projecting optical system 10a. The light receiving optical system 10 b includes a relay lens 16, a total reflection mirror 17, a light receiving aperture 18, a collimator lens 19, a ring lens 20, and a two-dimensional image sensor 22 (hereinafter referred to as “image sensor 22”). And including. These measurement optical systems 10 are provided in the transmission direction of the dichroic mirror 29 in the example of FIG.

  The measurement light source 11 is used to project a spot-shaped measurement index onto the fundus Er via the pupil. It is desirable that the light source 11 emits light in the infrared region where it is difficult for the subject to feel dazzling. However, it is not necessarily limited to this. In the present embodiment, the light source 11 is also used as an illumination light source for taking a transillumination image of the eye E. That is, the inside of the pupil of the eye E is illuminated by the fundus reflection light of the light beam (illumination light) emitted from the light source 11.

  The ring lens 20 of the light receiving optical system 10b is an optical element for shaping the fundus reflection light into a ring shape. The ring lens 20 has a lens portion formed in a ring shape and a light shielding portion in which a region other than the lens portion is coated with a light shielding coating. The ring lens 20 is optically conjugate with the pupil of the eye E. Ring-shaped fundus oculi reflection light (that is, a two-dimensional pattern image) via the ring lens 20 is received by the image sensor 22. The image sensor 22 outputs image information of the received two-dimensional pattern image to the control unit 100. As a result, it is possible to display a two-dimensional pattern image on the monitor 70 and to calculate the refractive power of the eye E based on the two-dimensional pattern image. As the image sensor 22, a light receiving element such as an area CCD can be used.

  Note that the measurement optical system 10 is not limited to the above. The measurement optical system 10 may be configured to include a Shack-Hartmann sensor. Of course, other measurement type apparatuses may be used (for example, a phase difference type apparatus that projects a slit).

  A beam splitter 29 is disposed between the objective lens 14 and the hall mirror 13. The beam splitter 29 guides a light beam from a fixation target presenting optical system 30 to be described later to the eye E, and guides reflected light from the anterior segment Ec of the eye E to the observation optical system 50. The beam splitter 29 reflects a part of the fundus reflected light emitted from the light source 11 and reflected by the fundus Er, guides it to the observation optical system 50, transmits other fundus reflected light, and receives the light receiving optical system 10b. Lead to.

  The fixation target presenting optical system 30 is a fixation optical system for fixing the eye E to be examined. The fixation target presenting optical system 30 includes a visible light source 31, a fixation target plate 32, a light projecting lens 33, a beam splitter 29, and an objective lens 14. When the visible light source 31 is turned on, the fixation target of the fixation target plate 32 is presented to the eye E. The visible light source 31 and the fixation target plate 32 are configured to be movable in the direction of the optical axis L3 by a slide mechanism (not shown). As the visible light source 31 and the fixation target plate 32 are moved in the direction of the optical axis L3, clouding of the eye E is performed.

  In front of the anterior segment of the eye E, a ring index projection optical system 45 and a working distance index projection optical system 46, which are examples of an alignment index projection optical system, are disposed. The ring index projection optical system 45 is used to project a ring index onto the cornea Ec. In the present embodiment, the ring index projection optical system 45 projects near-infrared light in a ring shape on the cornea Ec. As a result, as shown in FIG. 3, a ring index image R (also referred to as a Mayer ring image) is formed on the cornea Ec. The corneal apex (substantially corneal apex) is detected as the center position of the ring image. In FIG. 3, the ring index image R shows an intermittent ring image, but may be a continuous ring image. Of course, the shape of the index image for alignment detection is not limited to the ring shape, and various shapes such as a dot shape can be adopted.

  The ring index projected onto the cornea Ec can also be used as an index for corneal shape measurement. Further, the ring projection optical system 45 can also be used as anterior segment illumination for illuminating the anterior segment of the eye E. On the other hand, the working distance index projection optical system 46 is an optical system that emits near-infrared light for projecting an infinity index onto the cornea Ec of the eye E. Based on the positions of the ring index and the infinity index, the examiner can align the position of the ophthalmologic measurement apparatus 1 with respect to the eye E to be examined.

  The observation optical system (imaging optical system) 50 includes an imaging element 52 that captures a front image of the anterior segment of the eye E to be examined. In this embodiment, the observation optical system 50 shares the objective lens 14 and the beam splitter 29 with the fixation target presenting optical system 30. The observation optical system 50 includes a half mirror 35, an imaging lens 51, and a two-dimensional imaging element 52 (hereinafter referred to as “imaging element 52”). The imaging element 52 is a light receiving element having an imaging surface disposed at a position substantially conjugate with the anterior eye portion of the eye E to be examined. The imaging element 52 captures a front image of the anterior segment of the eye E. A transillumination image, which is a kind of anterior segment image, is also captured by the image sensor 52. An output from the image sensor 52 is input to the control unit 100. As a result, a live image of the front image captured by the image sensor 52 is displayed on the monitor 70 as an observation image. In the present embodiment, the observation optical system 50 detects an alignment index image (in this embodiment, a ring index and an infinity index) formed on the cornea Ec of the eye E by the index projection optical systems 45 and 46. Also serves as an optical system. The position of the alignment index image is detected based on the imaging result of the alignment index image by the image sensor 52.

  Next, the control system of the ophthalmologic measurement apparatus 1 will be described with reference to FIG. In the ophthalmologic measurement apparatus 1, each unit is controlled by the control unit 100. The control unit 100 is a processing device (processor) having an electronic circuit that performs control processing of each unit and arithmetic processing. The control unit 100 is realized by a CPU (Central Processing Unit), a memory, and the like. The control unit 100 is electrically connected to each of the light sources 11 and 31, the image sensors 22 and 52, the moving base 6 and the drive unit 7, the joystick 9, the monitor 70, the operation unit 90, and the flash memory 105.

  The flash memory 105 is a rewritable nonvolatile storage device. The flash memory 105 stores at least a program for causing the control unit 100 to perform a measurement operation.

  The control unit 100 controls each member of the ophthalmic measurement apparatus 1 based on the operation signal output from the operation unit 90. The operation unit 90 may be a pointing device such as a touch panel or a mouse, or may be a keyboard or the like.

<Operation of the device>
The measurement operation of the apparatus having the above configuration will be described. The examiner fixes the subject's face to the face support unit 4 and instructs the subject to fixate the fixation target on the fixation target plate 32. In this state, alignment of the measuring unit 8 with respect to the eye E is performed.

<Alignment (at the first measurement)>
At the time of alignment, the control unit 100 emits an alignment index and illumination light for anterior segment observation (light from the light source 11 in the example of FIG. 2). In addition, the control unit 100 causes the monitor 70 to display an anterior eye image observed through the observation optical system 50 as needed. That is, the front image (live image) of the anterior eye segment that is captured in substantially real time is displayed on the monitor 70. As shown in FIG. 3, in addition to the front image, the monitor 70 has a reticle mark LT, a ring index image (Meyer ring image) R projected by the projection optical system 45, and an infinite image projected by the working distance projection optical system 46. The far index image M is displayed (see FIG. 4). The reticle mark LT indicates the position of the measurement axis in the measurement unit 8 (in this embodiment, the measurement optical axis L1 of the measurement optical system 10). The position of the reticle mark LT (that is, the position of the measurement axis) may be the image center of the observation image as shown in FIG.

  Usually, alignment is performed so that the position of the measurement axis coincides with a predetermined position of the eye E (in this embodiment, the corneal apex). When the measurement axis coincides with the apex of the cornea, the examiner operates the joystick 9 while looking at the monitor 70 to move the position of the measurement unit 8 up and down so that the ring image R and the reticle mark LT are concentric. Adjust in the left-right direction (FIG. 3 (a) → FIG. 3 (b)). Thereafter, the position of the measuring unit 8 in the working distance direction is adjusted with reference to the indicator (or so that the ring image R becomes the thinnest).

  After the position of the measurement unit 8 is adjusted with respect to the eye E, the measurement trigger signal is input to the control unit 100 by operating the switch 9b. Thereby, the control unit 100 starts the eye refractive power measurement.

<Eye refractive power measurement>
In this case, first, preliminary measurement of eye refractive power is performed. Then, based on the result of the preliminary measurement, the light source 31 and the fixation target plate 32 are moved in the direction of the optical axis L2, so that the eye E is clouded. Thereafter, the eye refractive power is measured for the eye E to which the cloud is applied.

  In the measurement of the eye refractive power (and preliminary measurement), the control unit 100 obtains the eye refractive power by processing the output signal from the image sensor 22. The output signal from the image sensor 22 is stored in the memory 105 as image data (measurement image). Thereafter, the control unit 100 specifies the position of the ring image for each meridian of the ring based on the image data stored in the memory 105. Next, the control unit 100 approximates an ellipse using the least square method or the like based on the image position of the specified ring image. Then, the control unit 100 obtains the refraction error in each meridian direction from the approximate ellipse shape, and based on this, the eye refraction values (S (spherical power), C (column surface power), and A (astigmatism) of the eye E to be examined. Axis angle)) is calculated. Then, the measurement result is displayed on the monitor 70. In addition, the control unit 100 may store measurement results such as eye refraction values in the memory 105.

<Measurement error judgment>
For example, when measuring the eye E to be examined in which opacity (cataract) is present in the translucent body, there may be a case where the ring image is not properly captured by the imaging element 22 because the measurement light or fundus reflection light is blocked by the turbidity. . In this case, since a ring image is not picked up, eye refractive power cannot be obtained. In this case, the control unit 100 may determine that it is a measurement error and display an error on the monitor 70.

<Derivation of confidence coefficient>
Further, the control unit 100 may derive the reliability coefficient based on the output result from the image sensor 22 together with the measurement result (here, the eye refraction value). The reliability coefficient indicates the reliability of the measurement result of the eye refractive power (in other words, measurement accuracy). The reliability coefficient may be a coefficient that indicates the reliability of the measurement result in a plurality of stages. In the present embodiment, the reliability coefficient may be displayed on the monitor 70 together with the measurement result. FIG. 5 is a display example when the reliability coefficient is shown in five stages. The confidence coefficient surrounded by the rectangle is indicated by “E (including error 4 or less)”, “5”, “6”, “7”, “8”, and “9”. It shows high reliability.

  For example, when there is turbidity (cataract) in the measurement region of the eye E and when the eye E is an irregular astigmatism eye, irregular distortion or blurring may occur in the ring image. is there. In this case, since a shift occurs between the ellipse shape obtained by the ellipse approximation of the ring image and the ring image, the reliability is lowered. Therefore, the control unit 30 can obtain the reliability coefficient based on the amount of deviation in each meridian between the approximate ellipse of the ring image and the ring image. For example, the deviation amount in each meridian may be integrated, and a coefficient with lower reliability may be derived as the integrated value increases. For details of the method for deriving the reliability coefficient, refer to, for example, “Japanese Unexamined Patent Application Publication No. 2007-089715” and “Japanese Unexamined Patent Application Publication No. 2011-115300” by the present applicant.

<Re-measurement>
When an error occurs or when the reliability coefficient is low, remeasurement may be performed at an alignment position different from that at the first measurement. It is conceivable that a ring image can be captured better by changing the alignment position.

  In this case, the examiner operates the joystick 9 while looking at the monitor 70, so that the center of the ring image R (that is, the position of the apex of the cornea) and the reticle mark LT (position of the measurement axis) are shifted from each other. The position of the measurement unit 8 is adjusted in the vertical and horizontal directions so as to be disposed at (see FIG. 4). And the above-mentioned eye refractive power measurement may be performed again based on a measurement trigger signal.

  The examiner can search for an alignment position where a better measurement result can be obtained by repeatedly performing remeasurement while changing the alignment position in the eye E to which the measurement of the eye refractive power is difficult. However, changing the alignment position may cause a measurement error or lower reliability. In such a case, the examiner may perform a remeasurement by returning the alignment position to the alignment position (or the vicinity thereof) used in the previous measurement.

  Therefore, in the present embodiment, when re-measurement is performed, the index A (indicating the position of the measurement axis at the position of the measurement axis where the eye characteristics have been measured by the previous measurement in the anterior segment on the observed image is displayed. Hereinafter, display control for displaying “previous position index A” is performed by the control unit 100 (see FIG. 4). Details will be described below.

  For example, each time the measurement is performed, the control unit 100 includes position information (hereinafter referred to as “measurement position information”) indicating the position of the measurement axis with respect to the reference position of the anterior eye part when the eye refractive power is measured. Is “inspection position information” in this embodiment) and is stored in the memory 105 based on the observation image at the time of the eye refractive power measurement. The measurement position information includes at least the direction of the measurement axis and the deviation (distance) with respect to the reference position. Note that such measurement position information detection processing may be executed based on an input of a measurement trigger signal.

  The reference position here is a “constant” position in the anterior segment during each measurement. There is no need to have a completely constant position in the anterior segment at the time of each measurement, and an error that allows a sufficient reproducibility of the measurement results is allowed. That is, “constant” here includes substantially constant. For example, the reference position may be, for example, a characteristic part (for example, the center of the cornea or the center of the pupil) on the anterior eye part, or a position (for example, the ring index image R and infinity) separated from the characteristic part by a predetermined distance. Any position of the far index image M) or any other position may be used. As a specific example, the center position of the ring (substantially the position of the corneal apex) in the ring index image R is used as the reference position. The reference position may be sequentially detected by the control unit 100 from the anterior segment on the observation image.

  Then, at the time of re-measurement alignment, the control unit 100 reads (acquires) measurement position information in the previous measurement from the memory 105. Note that the measurement position information read from the memory 105 may be position information acquired on a different day (for example, the previous day).

  Based on the reference position detected from the anterior segment on the observation image and the read measurement position information, the previous position index A is superimposed on the observation image. That is, the previous position index A is displayed at a position away from the reference position in the observation image in the direction indicated by the measurement position information by the amount of deviation indicated by the information. This display control may be performed for each frame of the observation image. As a result, even if the position of the anterior segment changes in the observed image, the previous position index A follows the change. Thus, the control unit 100 may change the display position of the previous position index according to the movement of the reference position. More specifically, the display of the previous position index may be controlled so that the positional relationship between the reference position and the previous position index is maintained on the observation image.

  Thereby, even if the positional relationship between the eye and the apparatus changes, the previous position index can be accurately displayed. As a result, it becomes easy to perform remeasurement using the alignment position used in the previous measurement, which is the display position of the previous position index. In this embodiment, the alignment position used in the previous measurement can be reproduced by adjusting the position of the measurement unit 8 so that the reticle mark LT matches the previous position index A in the observed image (FIG. 4 ( a) ⇒ FIG. 4 (b)).

  As a result of the measurement being performed a plurality of times, when there are a plurality of measurement axis positions used in the previous measurement on the anterior segment, the measurement axis on which the previous position index A is displayed among the plurality of measurement axes There may be a single position or a plurality of positions.

  Further, as a result of the measurement being performed a plurality of times, when there are a plurality of measurement axis positions used in the previous measurement on the anterior segment, the position of the measurement axis where the previous position index A is displayed is determined by the examiner. It may be selected or may be automatically selected by the control unit 100. Of course, the previous position index A may be displayed at the position of each measurement axis. When the examiner selects, display control for displaying the previous position index A at the position of the measurement axis in the immediately previous measurement is performed by performing a predetermined operation on the operation unit 90 after each measurement. Also good. In addition, when the control unit 100 selects, the control unit 100 is based on information related to the reliability of each measurement performed in the past (for example, information indicating the presence or absence of a measurement error in the present embodiment). Thus, the position of the measurement axis for displaying the previous position index A may be selected. For example, the control unit 100 may display the previous position index A at the position of the measurement axis in the measurement having the highest reliability coefficient among the previous measurements.

  When the previous position index A is displayed, the control unit 100 may display guide information for aligning the measurement axis with the previous position index A together with the previous position index A. For example, it may be guide information indicating the direction in which the measuring unit 8 is moved as indicated by an arrow V shown in FIG. The guide information is not limited to graphics such as arrows, and may be text information.

  The control unit 100 performs movement control of the measurement unit 8 (drive control of the drive unit 6) so that the measurement axis moves to the previous position index A when a predetermined operation signal is input. Also good. For example, the above operation may be performed on the touch panel or the like (an example of the operation unit 90) based on an operation signal issued by an operation of selecting the previous position index A on the observation image. Thereby, the alignment position used in the previous measurement can be easily reproduced, and smooth manual alignment becomes possible.

  Further, the control unit 100 corresponds to the information C relating to the reliability of each measurement (for example, information indicating the presence or absence of a measurement error in the present embodiment) with respect to the previous position index A on the observation image. It may be displayed. For example, as shown in FIG. 5, information C regarding reliability may be displayed in association with the previous position index A with a line. Information about the reliability may be displayed in the vicinity of the previous position index A. For example, when a plurality of previous position indicators A are displayed on the observation image, the examiner can easily grasp which alignment position is more preferable.

  Note that the technique of the present embodiment is also useful when, for example, a new measurement is performed at a different date. For example, if the previous position information obtained by the previous measurement with respect to the eye E is present in advance, the control unit 100 determines the previous position on the observation image based on the previous position information when performing a new measurement. The indicator A may be displayed.

  In a new measurement performed anew on the day, the previous position index A may be displayed from the beginning (more specifically, from the alignment in the first measurement). However, for example, when a new measurement is performed by an examiner different from the previous measurement, the examiner may not wish to perform the measurement at the previous position from the beginning. Also, the position of the previous measurement axis as a result of the operation (eg, cataract surgery, corneal correction surgery, etc.) performed on the eye E between the previous measurement and the new measurement. May not be helpful in new measurements. Therefore, for example, in the case of a new measurement performed again from the previous measurement, the first measurement mode in which the previous position index A is not initially displayed and the second measurement mode in which the previous position index A is displayed from the beginning are provided. Or may be selected by the control unit 100. An example of the operation of the apparatus capable of selecting such two modes is shown in the flowchart of FIG.

  In the flowchart illustrated in FIG. 6, rough alignment is performed up to the position where the anterior segment is included in the observation image, and then one of the two modes is selected by the control unit 100 by the mode selection process. . In the mode selection process, for example, mode selection may be performed based on a signal output from the operation unit 90. In this case, for example, whether or not the examiner should perform a new measurement at the position on the previous measurement axis by hearing from the subject whether or not surgery has been performed since the previous measurement, checking the medical record, etc. Determine whether. When a predetermined operation on the operation unit 90 is performed according to the judgment of the examiner, a mode selection signal is output from the operation unit 90 to the control unit 100. Based on this signal, the control unit 100 selects a mode according to the judgment of the examiner.

  In the mode selection process, mode selection may be performed based on medical chart information of a subject (eye E) created in advance. The chart information may be stored in, for example, the memory 105 or a storage device of an external server connected to the control unit 100. In the medical record information, for example, information indicating the presence or absence of surgery in the eye E may be associated with the time axis together with the measurement results obtained so far for the eye E. In this case, when it is determined from the medical record information that the operation has been performed since the previous measurement, the control unit 100 selects the first measurement mode and the operation has not been performed since the previous measurement. When specified from the chart information, the second measurement mode may be selected. Further, the chart information may include a transillumination image taken at the previous measurement. In this case, in the mode selection process, the control unit 100 newly captures a transillumination image, and compares the transillumination image with the transillumination image captured at the previous measurement, so that the cataract surgery can be performed after the previous measurement. It may be determined whether or not it has been performed. And according to the determination result, control part 100 may choose a mode.

  In the mode selection process, when the first mode is selected, the control unit 100 performs the first measurement without displaying the previous position index A. That is, the measurement axis is aligned with the corneal apex, and measurement is performed at that position. When a measurement error occurs in the first measurement in the first mode or when a low reliability coefficient is derived, the control unit 100 detects the previous position index A based on the measurement performed on the day before the current measurement. May be displayed to prompt the examiner to perform measurement (re-measurement) after the second time.

  On the other hand, when the second mode is selected in the mode selection process, the control unit 100 displays the previous position index A based on the measurement performed on the day before the current measurement, and performs the first measurement. For this reason, at the time of the first measurement, the examiner is prompted by the previous position index A to align the measurement axis at the same position as the measurement performed on the day before the current measurement.

  Next, FIG. 7 shows another operation example in the case where a new measurement is performed at a different date. In the flowchart illustrated in FIG. 7, when a new measurement is performed again on the day, first, measurement at the corneal apex (an example of the reference position) is automatically performed, and according to the result, the previous measurement axis is measured. It is determined whether or not to perform the measurement at the position.

  Details will be described below. First, the control unit 100 projects an alignment index image onto the eye E. Further, the control unit 100 detects an alignment index image from the observation image obtained by the imaging element of the anterior ocular segment observation optical system 50, and the measurement axis of the measurement unit 8 matches the corneal center based on the detection result. As described above, the position of the measurement unit 8 is controlled (alignment control in the XY directions). Furthermore, the control unit 100 performs alignment control in the Z direction based on the detection results of the infinite distance target M, the ring index image R, and the like.

  After completion of the alignment control, the control unit 100 performs eye refractive power measurement (including preliminary measurement here). Whether or not to display the previous position index based on the measurement position information obtained on the day prior to the current measurement is determined based on the measurement result of the measurement at the corneal apex. The measurement result may be a measurement result of eye characteristics or an imaging result of eye E to be examined. For example, in the case of a measurement result, the determination as to whether or not the re-inspection is performed may be a measurement error or a low reliability coefficient. Further, for example, in the case of an imaging result, it may be an image evaluation value (for example, an image brightness level, a contrast, or the like) as to whether there is a shooting error.

  In the example of FIG. 7, for example, when the measurement at the corneal apex does not cause a measurement error and the reliability coefficient (reliability) obtained together with the measurement value is higher than the threshold value, the measurement is performed after the previous measurement. There is a possibility that the operation as described above is performed on the eye E or the measurement is not properly performed at the previous measurement. Therefore, in this case, the control unit 100 may determine that display of the previous position index is unnecessary.

  On the other hand, for example, when a measurement error occurs due to measurement at the corneal apex, or when the reliability coefficient (reliability) obtained together with the measurement value is lower than the threshold value, the position of the measurement axis is shifted from the corneal apex. It is considered that better measurement results may be obtained if re-measurement is performed at the previous measurement position arranged at a different position. Therefore, in this case, the previous position index A based on the measurement performed on the day before the current measurement may be displayed to prompt the examiner to perform the second and subsequent measurements (re-measurement).

  Further, instead of displaying the previous position index A, or together with the display, movement control of the measurement axis to the previous measurement position may be performed. When the control unit 100 determines that re-measurement is performed at the position of the measurement axis in the measurement performed on the day before the current measurement, the control unit 100 controls the drive of the drive unit 8 to control the drive before the current measurement. The measurement axis may be moved from the reference position to the position of the measurement axis in the measurement performed on the day.

  According to the above configuration, when the inspection at the previous position is not necessarily required and the inspection at the reference position is possible, the time required for the inspection can be shortened. Further, when the inspection at the reference position is difficult again, the measurement at the previous position can be performed smoothly.

  By performing the measurement operation as shown in FIG. 6 or FIG. 7, remeasurement by manual alignment can be performed more effectively.

  As mentioned above, although this indication was explained based on an embodiment, art contained in this indication can be changed variously, without being limited to the above-mentioned embodiment.

  For example, in the above-described embodiment, a case has been described in which the anterior ocular segment image from which measurement position information is acquired is an image obtained by reflection of illumination light at the anterior ocular segment. However, the present invention is not necessarily limited to this, and the measurement position information may be acquired using a transillumination image of the anterior segment as an anterior segment image. In this case, for example, the position of turbidity in the transillumination image or the position of the corneal bright spot (the bright spot generated by the corneal reflection of the illumination light) is detected as the reference position, and the position information of the measurement axis with respect to the reference position is You may acquire as measurement position information.

  Further, for example, in the above embodiment, the measurement position information obtained as a result of the previous measurement is stored in the memory 105 of the apparatus that performed the measurement, and the control unit 100 performs the memory 105 in the subsequent measurement (re-measurement). The case where the measurement position information is acquired from the above has been described. However, the present invention is not necessarily limited to this. For example, measurement position information obtained by previous measurement is stored in a storage device of an external server connected to the control unit 100 via a network. Measurement position information may be obtained from In this case, the measurement position information obtained by the first device may be used in the subsequent measurement performed by the second device.

  In the above description, an eye refractive power measurement device is illustrated as an example of an ophthalmic measurement device, but the present invention is not necessarily limited thereto. The technology of the present disclosure may be applied to other ophthalmic measurement devices (for example, a non-contact tonometer, an axial length measurement device, and the like). Further, the ophthalmologic apparatus according to the present disclosure is not limited to the ophthalmologic measurement apparatus. The ophthalmologic apparatus according to the present disclosure only needs to have an optometry system (for example, an optical system for optometry) for inspecting the eye E. For example, the technique of the present disclosure may be applied to an ophthalmic imaging apparatus that has an imaging optical system as an optometry system and images the eye E (for example, a fundus camera, an optical coherence tomography). The ophthalmologic apparatus may be, for example, an apparatus that optically measures or images the eye E, or may be an apparatus that measures or images the eye E with ultrasound.

  For example, the above-mentioned implementation is carried out with respect to “a tonometer that measures the intraocular pressure by optically detecting that the cornea Ec has been deformed by spraying a compressed fluid from the nozzle on the measurement axis to the eye E cornea Ec to be examined”. When the technique of the embodiment is applied, the reliability of measurement may be evaluated based on at least a signal indicating the state of corneal deformation from the start of corneal deformation to the end of corneal deformation. The above evaluation can be performed by using the fact that the signal shape is different between when the compressed fluid is accurately sprayed on the corneal apex and when the compressed fluid is sprayed at a position shifted from the corneal apex.

DESCRIPTION OF SYMBOLS 1 Ophthalmological measuring apparatus 7 Drive part 8 Measuring part 10 Measurement optical system 45 Ring index projection optical system 46 Working distance index projection optical system 50 Anterior eye part observation optical system 51 Imaging element 70 Monitor 90 Operation part E Eye to be examined L1 Measurement axis LT Reticle Mark V Arrow

Claims (10)

An optometry unit having an anterior ocular segment observation optical system having an imaging device that captures a front image of the anterior segment of the eye to be examined, and an optometry system for examining the eye to be examined having an optometry axis;
An acquisition means for acquiring the optometry position information indicating the position of the optometry axis with respect to the anterior eye portion, which is the test position information indicating the position of the optometry axis when the eye characteristics have been previously inspected using the optometry system;
A live image of a front image captured by the image sensor is displayed on a monitor, and a previous position index indicating a position of an optometric axis in a previous examination is displayed based on the examination position information in an anterior segment on the live image. Display control means capable of displaying;
An ophthalmic device. Detecting means for processing the front image and detecting a reference position on the anterior segment;
The ophthalmologic apparatus according to claim 1, wherein the display control unit displays the previous position index on the live image so that a positional relationship between the reference position and the previous position index is maintained. A transillumination image photographing means for photographing a transillumination image of the eye to be examined through the anterior ocular segment observation optical system;
Detecting means for processing the transillumination image and detecting a reference position on the anterior segment;
The ophthalmologic apparatus according to claim 1, wherein the display control unit displays the previous position index on the live image so that a positional relationship between the reference position and the previous position index is maintained. The optometry unit further includes an alignment index projection optical system that projects an alignment index used for alignment between the eye to be examined and the optometry axis onto the anterior eye part,
The ophthalmologic apparatus according to claim 2, wherein the detection unit detects the reference position based on an alignment index projected onto the eye to be examined.   The ophthalmologic apparatus according to claim 1, wherein the display control unit further displays a reticle mark indicating a current position of the optometry axis on the live image.   The display control means performs guide display for guiding the optometry axis to the position of the previous position index according to the current position of the optometry axis and the position of the previous position index in the live image. To 5. The ophthalmic apparatus according to any one of 5 to 5. A drive mechanism for adjusting the relative positional relationship between the eye to be examined and the optometry unit;
An operation unit for receiving operations from the examiner;
Alignment control means for controlling the drive mechanism so that the measurement axis moves to the position of the previous position index in response to a signal based on a predetermined operation from the operation unit;
An ophthalmologic apparatus according to any one of claims 1 to 6. An optometry unit having an anterior ocular segment observation optical system having an imaging device that captures a front image of the anterior segment of the eye to be examined, and an optometry system for examining the eye to be examined having an optometry axis;
A drive unit for adjusting the positional relationship of the optometry axis with respect to the eye to be examined;
Measurement position information indicating the position of the optometry axis in which the eye characteristics have been inspected, and obtaining means for acquiring optometry position information indicating the position of the optometry axis in the previous examination, which is an examination on the day prior to the current examination;
An alignment guiding means for controlling the driving unit to match the optometry axis with a reference position on the eye to be examined, and performing an examination in a state in which the measurement axis matches the reference position of the eye to be examined;
Determination processing means for determining whether to re-inspect at the position of the optometric axis in the previous inspection based on the inspection result by the alignment guiding means;
With
The alignment apparatus includes an induction unit that guides alignment of an optometric axis with respect to an eye based on a determination result of the determination processing unit. The guide means sequentially displays a live image of the front image captured by the image sensor on the monitor when the determination means determines that re-examination is performed at the position of the optometry axis in the previous examination, Display control means for displaying an examination position index indicating the position of the optometry axis in the previous examination based on the optometry position information at the position of the optometry axis in the previous examination in the anterior eye portion on the live image;
The ophthalmic apparatus according to claim 8.   When the determination unit determines that the reexamination is performed at the position of the optometry axis in the previous examination, the guide unit controls the driving of the driving unit, and the reference unit is set to the position of the optometry axis in the previous examination. The ophthalmologic apparatus according to claim 9, wherein the optometry axis is moved from a position.