JP6823339B2 - Ophthalmic equipment - Google Patents

Description

The present disclosure relates to an ophthalmic device for examining an eye to be inspected.

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

Japanese Unexamined Patent Publication No. 8-103414

However, with the conventional device, it cannot be said that the alignment with respect to the eye to be inspected in the second and subsequent examinations is smooth.

The present disclosure has been made in view of the problems of the prior art, and an object of the present invention is to provide an ophthalmologic measuring device capable of smoothly aligning an eye to be examined in the second and subsequent examinations.

The ophthalmic apparatus according to the first aspect of the present disclosure includes an anterior segment observation optical system having an imaging element for capturing a front image of the anterior segment of the eye to be inspected, and an optometry having an optometry axis for inspecting the eye to be inspected. This is optometry position information indicating the position of the optometry unit having the system, the driving unit for adjusting the positional relationship of the optometry axis with respect to the eye to be inspected, and the position of the optometry axis whose eye characteristics have been examined. The acquisition means for acquiring the optometry position information indicating the previous position, which is the position of the optometry axis in the previous examination, which is the examination on the previous day, and the driving unit so that the optometry axis matches the reference position on the optometry. Whether to perform the re-examination at the previous position based on the inspection result by the first guiding means and the first guiding means, which controls and performs the inspection in a state where the optometry axis matches the reference position of the eye to be inspected. The optometry position acquired by the acquisition means to align the optometry axis with respect to the eye to be inspected when the determination processing means for determining whether or not it is determined and the determination processing means determines that the re-examination is performed at the previous position. A second guiding means for guiding to the previous position based on the information is provided.

According to the present disclosure, it is possible to smoothly align the eye to be inspected in the second and subsequent examinations.

It is a figure which shows the appearance of the ophthalmic measuring apparatus. It is a schematic block diagram which showed the optical system which the measuring part of an ophthalmic measuring apparatus has, and the control system of an ophthalmic measuring apparatus. It is a figure which showed typically the observation image displayed on the monitor. It is a figure which shows on the observation image of the state which showed the index which shows the position of the measurement axis which was previously measured eye characteristic. It is a figure which shows the display example different from FIG. It is a flowchart which shows the flow of measurement in the case where the measurement is performed again from the previous measurement. It is a flowchart which shows the flow of measurement in the operation example different from FIG.

Hereinafter, the ophthalmic apparatus according to the embodiment of the present disclosure will be described with reference to the drawings. In the following embodiment, as an example of the ophthalmic device, the ophthalmic measuring device 1 for measuring the eye characteristics of the eye E to be inspected will be illustrated. In the ophthalmic measuring device 1, the eye characteristics of the eye E to be inspected are measured with respect to the measuring axis. The eye characteristics in the present disclosure include, for example, the refractive power of the eye, the aberration of the eye, the shape of the eye (more specifically, the curvature of the cornea, etc.), the size of the eye (more specifically, the axial length, etc.), and. , Intraocular pressure and the like. The ophthalmic measuring device 1 measures at least one of these eye characteristics. In the following description, a case where an autorefractometer for measuring refractive power is mainly applied as an ophthalmic measuring device 1 will be shown as a specific example.

First, with reference to FIG. 1, an example of the appearance configuration of the ophthalmic measuring device 1 is shown. The ophthalmic measuring device 1 shown in FIG. 1 is a so-called stationary device. The ophthalmic measuring device 1 mainly has a measuring unit 8. Although details will be described later, the measuring unit 8 is provided with at least an optical system used for measuring eye characteristics. The ophthalmology measuring device 1 may be a handheld device.

Further, in the example of FIG. 1, the ophthalmic measuring device 1 further includes a base 2, a face support unit 4, a moving table 6, a drive unit 7, a joystick 9, and a monitor 70.

The moving table 6 is supported by the base 2. The moving table 6 is moved on the base 2 in the vertical direction (Y direction) and the front-back direction (Z direction) by the operation of the joystick 9. Further, the 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 with the eye E to be inspected facing the measuring 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 to be inspected. When the examiner rotates the rotary knob 9a 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 to be inspected taken by the measurement unit 8 and a measurement result of the eye E to be inspected by the measurement unit 8.

Next, the optical system included in the measuring unit 8 of the ophthalmic measuring device 1 will be described with reference to FIG. The measuring unit 8 mainly includes a measuring optical system 10 and an observation optical system (imaging optical system) 50. Further, the measuring unit 8 in FIG. 2 has an fixation target display 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 to be inspected 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 to be inspected, and receives the reflected light from the eye E to be inspected by a detector (for example, a light receiving element, an image pickup element, etc.). Then, by processing the signal from the detector, the eye characteristics of the eye E to be inspected are acquired.

The measurement optical system 10 shown in FIG. 2 is used for measuring the refractive power of the eye 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 projection optical system 10a projects a spot-like luminous flux onto the fundus Er of the eye E to be inspected through the pupil of the eye E to be inspected. Further, the light receiving optical system 10b extracts the fundus reflected light in a ring shape through the peripheral portion of the pupil, and obtains a ring-shaped fundus reflection image mainly used for measuring the optical power of the two-dimensional image pickup element 22 (detector). Take an image with (one example).

In the example of FIG. 2, the projectile optical system 10a 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 hall mirror 13 and the objective lens 14 with the light projecting optical system 10a. Further, the light receiving optical system 10b includes a relay lens 16, a total reflection mirror 17, a light receiving diaphragm 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. In the example of FIG. 2, these measurement optical systems 10 are provided in the transmission direction of the dichroic mirror 29.

The measurement light source 11 is used to project a spot-shaped measurement index onto the fundus Er through the pupil. It is desirable that the light source 11 emits light in the infrared region, which makes it difficult for the subject to feel glare. However, it is not necessarily limited to this. Further, in the present embodiment, the light source 11 is also used as an illumination light source for photographing a transilluminated image of the eye E to be inspected. That is, the inside of the pupil of the eye E to be inspected is illuminated by the fundus reflected light of the luminous flux (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 reflected light into a ring shape. The ring lens 20 has a ring-shaped lens portion and a light-shielding portion in which a light-shielding coating is applied to a region other than the lens portion. Further, the ring lens 20 has a positional relationship optically conjugate with the pupil of the eye E to be inspected. The ring-shaped fundus reflected light (that is, a two-dimensional pattern image) transmitted through the ring lens 20 is received by the image sensor 22. The image sensor 22 outputs the image information of the received two-dimensional pattern image to the control unit 100. This makes it possible to display the two-dimensional pattern image on the monitor 70 and to calculate the refractive power of the eye E to be inspected based on the two-dimensional pattern image. As the image sensor 22, a light receiving element such as an area CCD can be used.

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 devices may be used (for example, a phase difference type device that projects a slit).

A beam splitter 29 is arranged between the objective lens 14 and the hole mirror 13. The beam splitter 29 guides the luminous flux from the fixation target display optical system 30, which will be described later, to the eye E to be inspected, and guides the reflected light from the anterior segment Ec of the eye E to the observation optical system 50. Further, the beam splitter 29 reflects a part of the fundus reflected light emitted from the light source 11 and reflected by the fundus Er, and guides the beam splitter 29 to the observation optical system 50, and at the same time, transmits the other fundus reflected light to receive the light receiving optical system 10b. Lead to.

The fixation target presentation optical system 30 is a fixation optical system for fixing the eye E to be inspected. The fixation target display optical system 30 includes a visible light source 31, a fixation plate 32, a projection 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 plate 32 is presented to the eye E to be inspected. The visible light source 31 and the fixation plate 32 are configured to be movable in the optical axis L3 direction by a slide mechanism (not shown). By moving the visible light source 31 and the fixation plate 32 in the direction of the optical axis L3, cloud fog of the eye E to be inspected is performed.

A ring index projection optical system 45 and a working distance index projection optical system 46, which are examples of the alignment index projection optical system, are arranged in front of the anterior segment of the eye E to be inspected. The ring index projection optical system 45 is used to project the ring index onto the corneal Ec. In the present embodiment, the ring index projection optical system 45 projects near-infrared light onto the cornea Ec in a ring shape. As a result, as shown in FIG. 3, a ring index image R (also referred to as a Mayerling image) is formed on the cornea Ec. The apex of the cornea (approximately the apex of the cornea) is detected as the central position of the ring image. Although the ring index image R shows an intermittent ring image in FIG. 3, it 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 on the cornea Ec can also be used as an index for measuring the shape of the cornea. The ring projection optical system 45 can also be used as anterior segment illumination for illuminating the anterior segment of the eye E to be inspected. 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 to be inspected. Based on the positions of the ring index and the infinity index, the examiner can align the position of the ophthalmologic measuring device 1 with respect to the eye E to be inspected.

The observation optical system (imaging optical system) 50 includes an image pickup element 52 that captures a frontal image of the anterior segment of the eye E to be inspected. In the present embodiment, the observation optical system 50 shares the objective lens 14 and the beam splitter 29 with the fixation target display optical system 30. Further, the observation optical system 50 includes a half mirror 35, an image pickup lens 51, and a two-dimensional image pickup element 52 (hereinafter, referred to as “image pickup element 52”). The image pickup element 52 is a light receiving element having an image pickup surface arranged at a position substantially conjugate with the anterior segment of the eye E to be inspected. The image sensor 52 captures a frontal image of the anterior segment of the eye E to be inspected. A transilluminated image, which is a type of anterior segment image, is also imaged by the image sensor 52. The output from the image sensor 52 is input to the control unit 100. As a result, the 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 (a ring index and an infinity index in the present embodiment) formed on the cornea Ec of the eye E to be inspected 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 image pickup result of the alignment index image by the image sensor 52.

Next, the control system of the ophthalmic measuring device 1 will be described with reference to FIG. Each part of the ophthalmic measuring device 1 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, or the like. The control unit 100 is electrically connected to each of the light sources 11, 31, the image pickup elements 22, 52, the moving table 6, 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 non-volatile storage device. The flash memory 105 stores at least a program for causing the control unit 100 to execute the measurement operation.

The control unit 100 controls each member of the ophthalmologic measurement device 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 device>
The measurement operation of the device having the above configuration will be described. The examiner fixes the subject's face to the face support unit 4 and instructs the examinee to fix the fixation target of the fixation plate 32. In this state, the measurement unit 8 is aligned with the eye E to be inspected.

<Alignment (at the time of initial measurement)>
At the time of alignment, the control unit 100 irradiates the alignment index and the illumination light for observing the anterior segment of the eye (light from the light source 11 in the example of FIG. 2). Further, the control unit 100 causes the monitor 70 to display the observation image of the anterior segment imaged via the observation optical system 50 at any time. That is, the monitor 70 displays a front image (live image) of the anterior segment of the eye, which is captured in substantially real time. As shown in FIG. 3, on the monitor 70, in addition to the front image, the reticle mark LT, the ring index image (Meyer ring image) R projected by the projection optical system 45, and the infinity 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 the present 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.

Normally, the alignment is performed so that the position of the measurement axis coincides with the predetermined position of the eye E to be inspected (in this embodiment, the apex of the cornea). When aligning the measurement axis with respect to 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)). After that, 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 to be inspected, the switch 9b is operated to input the measurement trigger signal to the control unit 100. As a result, the control unit 100 starts measuring the refractive power of the eye.

<Measurement of optical power>
In this case, first, a preliminary measurement of the optical power is performed. Then, based on the result of the preliminary measurement, the light source 31 and the fixation plate 32 are moved in the direction of the optical axis L2, so that cloud fog is applied to the eye E to be inspected. After that, the refractive power of the eye is measured for the eye E to be inspected with cloud fog.

In the measurement (and preliminary measurement) of the optical power, the control unit 100 obtains the optical 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 (measured image). After that, the control unit 100 identifies 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 the ellipse by using the least squares 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 elliptical shape, and based on this, the eye refraction values (S (spherical power), C (pillar surface power) and A (astigmatism) of the eye E to be inspected. Axial angle)) is calculated. Then, the measurement result is displayed on the monitor 70. Further, the control unit 100 may store the measurement result such as the ocular refraction value in the memory 105.

<Measurement error judgment>
For example, when measuring an eye E to be inspected in which opacity (cataract) is present in a translucent body, it is conceivable that the ring image may not be properly imaged by the image sensor 22 because the measurement light or the fundus reflected light is blocked by the opacity. .. In this case, since the ring image is not imaged, the optical power cannot be obtained. In this case, the control unit 100 may determine that the measurement error has occurred and display the error on the monitor 70.

<Drivation of confidence coefficient>
Further, the control unit 100 may derive a reliability coefficient based on the output signal from the image pickup device 22 together with the measurement result (here, the ocular refraction value). The reliability coefficient indicates the reliability (in other words, measurement accuracy) of the measurement result of the optical refractive power. The reliability coefficient may be a coefficient indicating the reliability of the measurement result in a plurality of stages. In this embodiment, the confidence factor may be displayed on the monitor 70 together with the measurement result. Note that FIG. 5 is a display example when the reliability coefficient is shown in five stages. The reliability coefficient surrounded by a rectangle is indicated by "E (including error 4 or less)", "5", "6", "7", "8", and "9". The higher the value, the higher the measurement position. It shows that it is highly reliable.

For example, when opacity (cataract) is present in the measurement area of the eye E to be inspected, or when the eye E to be inspected is an irregular astigmatic eye, the ring image may be irregularly distorted or blurred. is there. In this case, the shape of the ellipse obtained by approximating the ellipse of the ring image and the ring image are displaced from each other, so that the reliability is lowered. Therefore, the control unit 30 can obtain the reliability coefficient based on the amount of deviation between the approximate ellipse of the ring image and each meridian of the ring image. For example, the amount of deviation in each meridian may be integrated, and the larger the integrated value, the lower the reliability of the coefficient. For the detailed derivation method of the reliability coefficient, refer to, for example, "Japanese Patent Laid-Open No. 2007-089715" and "Japanese Patent Laid-Open No. 2011-115300" by the present applicant.

<Remeasurement>
If an error occurs, or if the reliability coefficient is low, remeasurement may be performed at an alignment position different from that at the time of initial measurement. It is conceivable that the ring image can be better captured 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 (the position of the measurement axis) are deviated from each other. The position of the measuring unit 8 is adjusted in the vertical and horizontal directions so as to be arranged in (see FIG. 4). Then, the above-mentioned ocular refractive power measurement may be performed again based on the measurement trigger signal.

In the eye E to be inspected, where it is difficult to measure the refractive power of the eye, the examiner can search for an alignment position at which a better measurement result can be obtained by repeating the remeasurement while changing the alignment position. However, by changing the alignment position, a measurement error may occur or the reliability may be lowered. In such a case, the examiner may return the alignment position to the alignment position (or its vicinity) used in the previous measurement and perform the measurement again.

Therefore, in the present embodiment, when remeasurement is performed, the index A (indicating the position of the measurement axis is indicated at the position of the measurement axis whose ocular characteristics have been measured by the previous measurement in the anterior segment on the observation image). Hereinafter, the display control for displaying the "previous position index A") is performed by the control unit 100 (see FIG. 4). Details will be described below.

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

The reference position referred to here is a “constant” position in the anterior segment at the time of each measurement. It is not necessary to have a completely constant position in the anterior segment at the time of each measurement, and an error that sufficiently obtains reproducibility of the measurement result is allowed. That is, the term "constant" here includes substantially constant. The reference position may be, for example, a feature site on the anterior segment of the eye (eg, the center of the cornea, the center of the pupil), or a position separated from the feature site by a predetermined distance (for example, the ring index image R and infinity). It may be any position of the far index image M), or it may be a position other than this. As a specific example, here, the center position of the ring (position of the apex of the cornea) 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 of the observation image.

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

Based on the reference position detected from the anterior segment of the observation image and the read measurement position information, the previous position index A is superimposed and displayed on the observation image. That is, the previous position index A is displayed at a position separated 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 observed image. As a result, even if the position of the anterior segment changes in the observation image, the previous position index A follows the change. In this way, 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.

As a result, even if the positional relationship between the eye and the device 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 the present embodiment, the alignment position used in the previous measurement can be reproduced by adjusting the position of the measuring unit 8 so that the reticle mark LT matches the previous position index A in the observation image (FIG. 4 (FIG. 4). a) ⇒ Fig. 4 (b)).

If there are multiple measurement axis positions on the anterior segment of the eye as a result of the measurement being performed multiple times, the measurement axis in which the previous position index A is displayed is displayed among the multiple measurement axes. The position of may be one at the maximum, or may be a plurality of positions.

Further, as a result of performing the measurement a plurality of times, when there are a plurality of measurement axis positions used in the previous measurement on the anterior segment of the eye, the position of the measurement axis on which the previous position index A is displayed is determined by the examiner. It may be selected, or it 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, by performing a predetermined operation on the operation unit 90 after each measurement, display control for displaying the previous position index A at the position of the measurement axis in the immediately preceding measurement is performed. May be good. When the control unit 100 selects, the control unit 100 is based on information on the reliability of each measurement previously performed (for example, in the present embodiment, a reliability coefficient or information indicating the presence or absence of a measurement error). The position of the measurement axis on which the position index A is displayed last time 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 conventional 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, as shown by the arrow V shown in FIG. 4, the guide information may indicate the direction in which the measuring unit 8 is moved. The guide information is not limited to a figure such as an arrow, but may be text information.

Further, 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 position index A last time when a predetermined operation signal is input. May be good. For example, the above operation may be performed on a touch panel or the like (an example of the operation unit 90) based on an operation signal generated by the operation of selecting the previous position index A on the observation image. As a result, 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 regarding the reliability of each measurement (for example, in the present embodiment, the reliability coefficient or the information indicating the presence or absence of a measurement error) with respect to the previous position index A on the observation image. It may be attached and displayed. For example, as shown in FIG. 5, the information C regarding the reliability may be displayed in association with the previous position index A by a line. Information on reliability may be displayed in the vicinity of the previous position index A. For example, when a plurality of previous position indexes A are displayed on the observation image, it is easy for the examiner to grasp which alignment position is more preferable.

The technique of the present embodiment is also useful, for example, when a new measurement is performed on a new day. For example, if the previous position information obtained in the previous measurement for the eye E to be inspected exists in advance, the control unit 100 will perform the previous position on the observation image based on the previous position information at the time of new measurement. The index A may be displayed.

In the new measurement performed on a new day, the previous position index A may be displayed from the beginning (more specifically, from the time of 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 want to perform the measurement at the previous position from the beginning. In addition, as a result of surgery (for example, cataract surgery, corneal correction surgery, etc.) performed on the eye E to be examined between the previous measurement and the new measurement, the position of the previous measurement axis May not be helpful in new measurements. Therefore, for example, in the case of a new measurement performed on a different day from the previous measurement, there are a first measurement mode in which the previous position index A is not displayed at the beginning and a second measurement mode in which the previous position index A is displayed from the beginning. , May be selected by the control unit 100. An operation example of the device 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 above 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 the 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 asking the subject whether or not there has been an operation or the like since the previous measurement or checking the medical record. To judge. When a predetermined operation on the operation unit 90 is performed according to the judgment of the examiner, the operation unit 90 outputs a mode selection signal to the control unit 100. The control unit 100 selects a mode according to the judgment of the examiner based on this signal.

Further, in the mode selection process, the mode may be selected based on the medical record information of the subject (eye to be inspected E) created in advance. The medical record information may be stored in, for example, the memory 105 or the storage device of the 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 to be inspected may be associated with the time axis together with the measurement results so far for the eye E to be inspected. In this case, when it is specified 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. The second measurement mode may be selected when specified from the chart information. In addition, the chart information may include a transillumination image taken at the time of 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 taken at the time of the previous measurement, so that cataract surgery can be performed after the previous measurement. It may be determined whether or not it has been performed. Then, the control unit 100 may select a mode according to the determination result.

When the first mode is selected in the mode selection process, the control unit 100 performs the first measurement without displaying the previous position index A. That is, the measurement axis is aligned with the apex of the cornea, and the measurement is performed at that position. When a measurement error occurs in the first measurement in the first mode, a low reliability coefficient is derived, or the like, the control unit 100 uses 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 (remeasurement).

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. Therefore, the examiner is urged to align the measurement axis with the same position as the measurement performed on the day before the current measurement by the previous position index A at the time of the first measurement.

Next, FIG. 7 shows another operation example when a new measurement is performed on a different day. In the flowchart illustrated in FIG. 7, when a new measurement is performed on a new day, the measurement at the apex of the cornea (an example of the reference position) is automatically performed, and the measurement of the previous measurement axis is performed according to the result. It is decided whether or not to make a measurement at the position.

The details will be described below. First, the control unit 100 projects an alignment index image on the eye E to be inspected. Further, the control unit 100 detects an alignment index image from the observation image obtained by the image sensor of the anterior segment observation optical system 50, and the measurement axis of the measurement unit 8 coincides with the center of the cornea based on the detection result. As described above, the position of the measuring unit 8 is controlled (alignment control in the XY direction). Further, the control unit 100 performs alignment control in the Z direction based on the detection results of the infinite hyperopia M, the ring index image R, and the like.

After the above alignment control is completed, the control unit 100 executes the measurement of the optical refractive power (here, including the preliminary measurement). Then, whether or not to display the previous position index based on the measurement position information obtained on the day before the current measurement is determined based on the measurement result by the measurement at the apex of the cornea. The measurement result may be a measurement result of eye characteristics or an imaging result of the eye E to be inspected. As a determination of whether or not to perform the re-inspection, for example, in the case of the measurement result, whether or not it is a measurement error or whether or not the reliability coefficient is low may be determined. Further, for example, in the case of an imaging result, it may be a shooting error or not, and an image evaluation value (for example, the brightness level of the image, contrast, etc.).

In the example of FIG. 7, for example, when the measurement at the apex of the cornea does not cause a measurement error and the reliability coefficient (reliability) obtained together with the measured value is higher than the threshold value, it is after the previous measurement. It is conceivable that the above-mentioned operation may be performed on the eye E to be inspected, or the measurement may not be performed properly at the time of the previous measurement. Therefore, in this case, the control unit 100 may determine that the previous position index display is unnecessary.

On the other hand, for example, if a measurement error occurs due to measurement at the apex of the cornea, or if the reliability coefficient (reliability) obtained together with the measured value is lower than the threshold value, the position of the measurement axis deviates from the apex of the cornea. It is considered that better measurement results may be obtained by performing remeasurement at the previous measurement position, which is placed at the same 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 (remeasurement).

Further, the movement control of the measurement axis to the previous measurement position may be performed instead of or together with the display of the previous position index A. When the control unit 100 determines that the remeasurement 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 and 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, the inspection at the previous position is not always necessary, and when 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 smoothly performed.

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

Although the present disclosure has been described above based on the embodiments, the techniques included in the present disclosure can be variously modified without being limited to the above embodiments.

For example, in the above embodiment, the case where the anterior segment image from which the measurement position information is acquired is an image obtained by reflection of the illumination light at the anterior segment has been described. However, the present invention is not limited to this, and the measurement position information may be acquired by using the transilluminated image of the anterior segment as the anterior segment image. In this case, for example, the position of opacity 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 obtained. It may be acquired 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 device that performed the measurement, and in the later measurement (remeasurement), the control unit 100 stores the memory 105. The case of acquiring the measurement position information from is described. However, the present invention is not limited to this, and for example, the measurement position information obtained by the conventional measurement is stored in the storage device of the external server connected to the control unit 100 via the network, and in the later measurement, this storage device. The measurement position information may be acquired 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.

Further, in the above description, the ophthalmic refractive power measuring device has been illustrated as an example of the ophthalmic measuring device, but the present invention is not necessarily limited to this. The techniques of the present disclosure may be applied to other ophthalmic measuring devices (eg, non-contact tonometers, axial length measuring devices, etc.). Further, the ophthalmic apparatus according to the present disclosure is not limited to the ophthalmic measuring apparatus. The ophthalmic apparatus according to the present disclosure may have an optometry system (for example, an optical system for optometry) for examining the eye E to be examined. For example, the technique of the present disclosure may be applied to an ophthalmic imaging device (for example, a fundus camera, an optical interference tomometer) that has an imaging optical system as an optometry system and images an eye to be inspected E. Further, the ophthalmic apparatus may be, for example, an apparatus for optically measuring or photographing the eye to be inspected E, or an apparatus for measuring or photographing the eye to be inspected E by ultrasonic waves.

For example, the above-mentioned implementation is applied to "a tonometer that measures intraocular pressure by spraying a compressed fluid from a nozzle on the measurement axis to the E-cornea Ec to be inspected and optically detecting that the cornea Ec has a predetermined deformation". When applying the technique of morphology, the reliability evaluation of the measurement may be performed at least based on the signal indicating the state of the corneal deformation from the start of the corneal deformation to the end of the corneal deformation. The above evaluation can be performed by utilizing the fact that the signal shape differs between the case where the compressed fluid is sprayed accurately on the corneal apex and the case where the compressed fluid is sprayed at a position deviated from the corneal apex.

1 Ophthalmology measuring device 7 Driving unit 8 Measuring unit 10 Measuring optical system 45 Ring index projection optical system 46 Working distance index projection optical system 50 Front eye observation optical system 51 Imaging element 70 Monitor 90 Operation unit E Eye to be inspected L1 Measurement axis LT reticle Mark V arrow

Claims (2)

An optometry unit having an anterior segment observation optical system having an image pickup element for capturing a frontal image of the anterior segment of the eye to be inspected, and an optometry system having an eye examination axis for inspecting the eye to be inspected
A drive unit for adjusting the positional relationship of the optometry axis with respect to the optometry subject,
Acquires optometry position information indicating the position of the optometry axis whose eye characteristics have been inspected, which is the position of the optometry axis in the previous examination which is the examination on the day before the current examination. Acquisition method and
A first guiding means for controlling the driving unit so that the optometry axis coincides with the reference position on the optometry and performing an examination in a state where the optometry axis coincides with the reference position of the optometry.
A determination processing means for determining whether or not to perform a re-inspection at the previous position based on the inspection result by the first guidance means, and
When the determination processing means determines that the re-examination is performed at the previous position, the alignment of the optometry axis with respect to the eye to be inspected is guided to the previous position based on the optometry position information acquired by the acquisition means. An ophthalmic device comprising a second guiding means. The second guiding means sequentially displays a live image of the front image captured by the image pickup element on the monitor when the determination processing means determines that the re-inspection is performed at the previous position, and the second guiding means. the last position in the anterior portion of the live image, the display on the basis of the inspection position index indicating the last position on the eye position information, ophthalmic apparatus according to claim 1.