JP2019058441A - Ophthalmologic apparatus and control method - Google Patents

Abstract

To provide an ophthalmologic apparatus capable of suppressing reduction of measurement accuracy even when intensity of a pattern light for measuring eye refractive force of an eye to be examined is high, and a control method thereof.SOLUTION: An ophthalmologic apparatus comprises: an optical system for projecting a pattern light based on a light from a light source to an eye to be examined, and receiving a return light of the pattern light from the eye to be examined on an imaging element through a focusing lens on which a focal position can be changed; an analysis part for calculating an eye refractive force value of the eye to be examined based on a pattern image; and a control part 110 for, determining a first measurement condition including at least one of a light amount of a light source, an exposure time of the imaging element, a detection sensitivity, and a control content to the focusing lens, based on a first pattern image, determining a second measurement condition including at least one of a light amount, an exposure time, a detection sensitivity, and a control content based on a second pattern image acquired under the first measurement condition, then, causing the analysis part to calculate the eye refractive force value based on a third pattern image acquired by the imaging element, in a state in which the eye to be examined is subjected to fogging view under the second measurement condition.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an ophthalmologic apparatus and a control method thereof.

  As an ophthalmologic apparatus, one capable of measuring the eye refractive power of an eye to be examined is known. For example, in Patent Document 1, a measurement pattern is projected on the fundus of the subject's eye, reflected light from the fundus is extracted from the center of the pupil, and the eye refractive power value is calculated from the size of the acquired pattern image and the degree of deformation. Ophthalmologic apparatus is disclosed.

  In such an ophthalmologic apparatus, temporary measurement is performed for the purpose of determining in advance the movement amount of the focusing unit according to the adjustment power of the eye to be examined. For example, in Patent Document 2, based on the movement amount of the focusing unit obtained by temporary measurement, the focusing unit is moved so that the measurement pattern image is substantially in focus at the fundus of the eye to be examined, An ophthalmologic apparatus is disclosed that measures the exact eye refractive power of an eye to be examined by performing this measurement after fogging the optometry.

JP, 2016-187461, A JP 2007-159850 A

  When the line width of the pattern image projected onto the fundus of the eye to be examined is thick, the pattern image on the sensor before and after movement even if the focusing unit is moved based on the movement amount of the focusing unit obtained by temporary measurement. The change in brightness (illuminance) is small. Therefore, when the main measurement is performed under the measurement conditions determined by the temporary measurement, the measurement accuracy does not matter.

  On the other hand, if the line width of the pattern image to be projected onto the fundus is thin and the luminance is high, the edge portion of the pattern image to be obtained becomes sharp, and therefore the influence of vignetting or the like in the eye on the measurement light beam becomes difficult. From this, it is possible to perform stable measurement even on an eye to be examined which has turbidity in the eye such as a cataract eye. However, when the line width of the pattern image is thin and the luminance is high, the change in the brightness of the pattern image before and after the movement of the focusing portion becomes large. Therefore, when the main measurement is performed under the measurement conditions determined by the temporary measurement, the S / N ratio sufficient for image detection can not be obtained, and the measurement accuracy may be reduced.

  The present invention has been made in view of such circumstances, and an object thereof is to reduce the measurement accuracy even when the line width of a pattern image for measuring the eye refractive power of an eye to be examined is thin and the luminance is high. It is an object of the present invention to provide an ophthalmologic apparatus capable of suppressing

  In the first aspect of the embodiment, pattern light based on light from a light source is projected onto an eye to be inspected, and return light from the eye to be examined of the pattern light is changed by an imaging element through a focusing lens whose focal position can be changed. An optical system that receives light, an analysis unit that calculates an eye refractive power value of the subject's eye based on a pattern image obtained by the image sensor, and a light source for the light source based on a first pattern image obtained by the image sensor A first measurement condition including at least one of a light amount, an exposure time of the image sensor, a detection sensitivity of the image sensor, and control content for the focusing lens is determined, and the image sensor detects the first measurement condition. A second measurement condition including at least one of the light quantity, the exposure time, the detection sensitivity, and the control content is determined based on the obtained second pattern image, and the eye to be examined is determined under the second measurement condition. Cloudy view A control unit for calculating the analysis unit the eye refractive power value based on the third pattern image obtained by the imaging device in a state where a ophthalmic device comprising a.

  In the second aspect of the embodiment, in the first aspect, the light source is disposed so as to be approximately optically conjugate with the fundus of the eye to be examined, and the optical system is optically An aperture disposed at a position substantially conjugate to the light source and formed with a light transmitting portion for transmitting light from the light source, and a deflection member for deflecting the light from the light source and guiding the light to the light transmitting portion; The light transmitted through the light portion may be projected onto the eye as the pattern light.

  In the third aspect of the embodiment, in the first aspect or the second aspect, the control unit executes the first luminance reduction control when the luminance of the first pattern image is high, and the luminance of the first pattern image is generated. The first brightness increase control is performed when the second pattern image has a high brightness, the second brightness decrease control is performed when the second pattern image has a high brightness, and the second brightness increase control is performed when the second pattern image has a low brightness. It is also good.

  In a fourth aspect of the embodiment, in the third aspect, at least one of the first luminance reduction control and the second luminance reduction control is configured to reduce the detection sensitivity based on the luminance of the pattern image. After the first detection sensitivity control to lower the luminance of the first exposure control, the first exposure time control to lower the luminance of the pattern image by shortening the exposure time may be performed.

  Further, in a fifth aspect of the embodiment, in the fourth aspect, at least one of the first luminance reduction control and the second luminance reduction control is configured to reduce the light amount after the first exposure time control. The first light amount control may be performed to lower the luminance of the light source.

  Further, in a sixth aspect of the embodiment, in the fourth aspect or the fifth aspect, the optical system includes a rotary prism disposed in a light path of the pattern light, and the first exposure time control is performed by the rotary prism The exposure time may be shortened to be equal to or higher than a lower limit time defined by the rotational speed.

  In the seventh aspect of the embodiment, in any one of the third to sixth aspects, at least one of the first luminance increase control and the second luminance increase control is configured to generate a pattern image by increasing the light amount. After the second light amount control to increase the luminance, a second exposure time control to increase the luminance of the pattern image by extending the exposure time may be performed.

  In the eighth aspect of the embodiment, in the seventh aspect, at least one of the first luminance increase control and the second luminance increase control is a pattern by increasing the detection sensitivity after the second exposure time control. A second detection sensitivity control may be performed to increase the brightness of the image.

  Moreover, in a ninth aspect of the embodiment, in any of the first aspect to the eighth aspect, the pattern light may be ring-shaped light.

  The tenth aspect of the embodiment projects pattern light based on light from a light source onto an eye to be examined, and uses an imaging element via a focusing lens whose focal position can change return light from the eye to be examined of the pattern light. It is a control method of an ophthalmologic apparatus which measures the refractive power of the said to-be-tested eye by light-receiving, Comprising: The light quantity of the said light source, the exposure time of the said image sensor based on the 1st pattern image obtained by the said image sensor A first measurement condition determining step of determining a first measurement condition including at least one of detection sensitivity of the image pickup device and control content for the focusing lens; and an image pickup device obtained under the first measurement condition A second measurement condition determining step of determining a second measurement condition including at least one of the light intensity, the exposure time, the detection sensitivity, and the control content based on a second pattern image; A control method of an ophthalmologic apparatus, comprising: a fog control step of fogging the eye under the condition; and a measuring step of measuring the refractive power in the fog control step in the fog control step. .

  In an eleventh aspect of the embodiment, in the tenth aspect, at least one of the first measurement condition determination step and the second measurement condition determination step is a first determination determining whether or not the luminance of the pattern image is high. A second determination step of determining whether the detection sensitivity is higher than a first threshold when it is determined that the luminance is high in the first determination step; and the detection sensitivity in the second determination step Is determined to be equal to or greater than the first threshold, a first detection sensitivity control step for reducing the detection sensitivity, and when it is determined that the detection sensitivity is less than the first threshold in the second determination step, A third determination step of determining whether the exposure time is equal to or greater than a second threshold, and determining that the exposure time is equal to or greater than the second threshold in the third determination step The light intensity is equal to or greater than the third threshold when it is determined that the detection sensitivity is less than the second threshold in the first exposure time control step of shortening the exposure time and the third determination step. It may also include a fourth determination step of determining whether or not the light amount is lower than the third threshold value in the fourth determination step, and a first light amount control step of decreasing the light amount.

  In a twelfth aspect of the embodiment, in the eleventh aspect, the ophthalmologic apparatus includes a rotary prism disposed in an optical path of the pattern light, and the second threshold is defined by a rotational speed of the rotary prism. It may be more than the lower limit time.

  Moreover, in a thirteenth aspect of the embodiment, in any of the tenth aspect to the twelfth aspect, at least one of the first measurement condition determination step and the second measurement condition determination step has low luminance of the pattern image or not A sixth determination step of determining whether the light amount is equal to or less than a fourth threshold when it is determined that the luminance is low in the fifth determination step; When it is determined in the determination step that the light amount is equal to or less than the fourth threshold, when it is determined that the light amount exceeds the fourth threshold in a second light amount control step that raises the light amount and in the sixth determination step A seventh determination step of determining whether the exposure time is less than or equal to a fifth threshold, and determining that the exposure time is less than or equal to the fifth threshold in the seventh determination step When the exposure time is determined to exceed the fifth threshold in the second exposure time control step of lengthening the exposure time and the seventh determination step, the detection sensitivity is equal to or less than the sixth threshold And a second detection sensitivity control step of increasing the detection sensitivity when it is determined in the eighth determination step that the detection sensitivity is less than or equal to the sixth threshold value. May be.

  Further, in a fourteenth aspect of the embodiment, the light source is disposed so as to be approximately optically conjugate to the fundus of the eye to be examined, and the ophthalmologic apparatus is to be substantially optically conjugate to the pupil of the eye to be examined A diaphragm formed on the light source to transmit light from the light source, and a deflecting member for deflecting the light from the light source and guiding the light to the light transmitting portion; Light may be projected on the eye as the pattern light.

It is the schematic which shows the structural example of the optical system of the ophthalmologic apparatus which concerns on embodiment. It is the schematic which shows the structural example of the optical system of the ophthalmologic apparatus which concerns on embodiment. It is the schematic which shows the structural example of the optical system of the ophthalmologic apparatus which concerns on embodiment. It is the schematic which shows the structural example of the processing system of the ophthalmologic apparatus which concerns on embodiment. It is the schematic which shows the structural example of the processing system of the ophthalmologic apparatus which concerns on embodiment. It is the schematic which shows the flow of the operation example of the ophthalmologic apparatus which concerns on embodiment. It is the schematic which shows the flow of the operation example of the ophthalmologic apparatus which concerns on embodiment. It is the schematic which shows the flow of the operation example of the ophthalmologic apparatus which concerns on embodiment. It is the schematic which shows the flow of the operation example of the ophthalmologic apparatus which concerns on embodiment. It is the schematic which shows the flow of the operation example of the ophthalmologic apparatus which concerns on embodiment. It is the schematic which shows the structural example of the optical system of the ophthalmologic apparatus which concerns on the modification of embodiment. It is the schematic which shows the structural example of the optical system of the ophthalmologic apparatus which concerns on the modification of embodiment.

  An example of an embodiment of an ophthalmologic apparatus according to the present invention will be described in detail with reference to the drawings. In addition, it is possible to use the description content of the literature referred in this specification, and arbitrary well-known techniques in the following embodiment.

  The ophthalmologic apparatus according to the embodiment can perform objective measurement and subjective examination. The objective measurement is a measurement method of acquiring information on the subject's eye mainly using a physical method without referring to the response from the subject.

  The objective measurement includes the measurement for acquiring the characteristics of the eye to be examined and the imaging for acquiring the image of the eye to be inspected. Objective measurement includes objective refraction measurement, corneal shape measurement, intraocular pressure measurement, fundus photography, optical interference measurement and the like. On the other hand, a subjective test is a measurement method of acquiring information using a response from a subject. Subjective examinations include subjective refraction measurement such as distance vision examination, near vision examination, contrast examination, glare examination, and visual field examination.

  The ophthalmologic apparatus according to the embodiment can measure at least the objective refractive power, and can additionally perform any subjective test and any other objective measurement.

  Hereinafter, the fundus conjugate position is a position optically substantially conjugate with the fundus of the subject's eye in a state in which alignment is completed, and means a position optically conjugate with the fundus of the subject's eye or its vicinity. Similarly, the pupil conjugate position is a position optically substantially conjugate with the pupil of the subject eye in a state in which alignment is completed, and means a position optically conjugate with the pupil of the subject eye or the vicinity thereof. .

<Configuration of optical system>
The structural example of the optical system of the ophthalmologic apparatus which concerns on FIG. 1 at embodiment is shown. The ophthalmologic apparatus 1000 is an optical system for inspecting the eye E to be examined, and includes a Z alignment system 1, an XY alignment system 2, a kerato measurement system 3, a target projection system 4, an anterior segment observation system 5, a reflex measurement projection system 6 and a reflex measurement light receiving system 7.

(Anterior eye observation system 5)
The anterior eye observation system 5 captures a video of the anterior eye of the eye E to be examined. In the optical system passing through the anterior eye observation system 5, the imaging surface of the imaging element 59 is disposed at the pupil conjugate position Q. The anterior eye illumination light source 51 illuminates the anterior eye of the eye E with illumination light (for example, infrared light). The light reflected by the anterior segment of the eye E passes through the objective lens 52, passes through the dichroic mirror 53, passes through the half mirror 54, passes through the relay lenses 55 and 56, and passes through the dichroic mirror 57. . The light transmitted through the dichroic mirror 57 is imaged by the imaging lens 58 on the imaging surface of the imaging element 59 (area sensor). The imaging device 59 performs imaging and signal output at a predetermined rate. The output (video signal) of the imaging element 59 is input to the processing unit 9 described later. The processing unit 9 displays an anterior segment image based on the video signal on a display screen of a display unit described later. The anterior segment image is, for example, an infrared moving image.

(Z alignment system 1)
The Z alignment system 1 projects the light (infrared light) for performing alignment in the optical axis direction (front-rear direction, Z direction) of the anterior eye observation system 5 onto the eye E. The light output from the Z alignment light source 11 is projected onto the cornea of the eye E to be examined, reflected by the cornea, and imaged on the sensor surface of the line sensor 13 by the imaging lens 12. When the position of the corneal apex changes in the direction of the optical axis of the anterior segment observation system 5, the projection position of light on the sensor surface of the line sensor 13 changes. The processing unit 9 obtains the position of the corneal apex of the eye E based on the projection position of light on the sensor surface of the line sensor 13, and controls the mechanism for moving the optical system based on this to execute the Z alignment.

(XY alignment system 2)
The XY alignment system 2 uses light (infrared light) for alignment in a direction (horizontal direction (X direction), vertical direction (Y direction)) orthogonal to the optical axis of the anterior eye observation system 5 as the eye E Irradiate. The XY alignment system 2 includes an XY alignment light source 21 provided in an optical path branched from the anterior segment observation system 5 by a half mirror 54. The light output from the XY alignment light source 21 is reflected by the half mirror 54 and projected onto the eye E through the anterior eye observation system 5. The reflected light from the cornea of the eye to be examined E is guided to the imaging element 59 through the anterior eye observation system 5.

  An image based on the reflected light (bright spot image) is included in the anterior segment image. The processing unit 9 displays the anterior segment image including the bright spot image and the alignment mark on the display screen of the display unit. When performing XY alignment manually, the user performs an operation of moving the optical system so as to introduce a bright spot image into the alignment mark. When the alignment is automatically performed, the processing unit 9 controls a mechanism that moves the optical system so that the displacement of the bright spot image with respect to the alignment mark is cancelled.

(Kerat measurement system 3)
The kerat measurement system 3 projects a ring-shaped luminous flux (infrared light) for measuring the shape of the cornea of the eye E to be examined on the cornea. The kerato plate 31 is disposed between the objective lens 52 and the eye E to be examined. On the back side (the objective lens 52 side) of the kerato plate 31, a kerato ring light source (not shown) is provided. By illuminating the kerato plate 31 with the light from the keratoring light source, a ring-like light beam is projected on the cornea of the eye to be examined E. The reflected light (keratling image) from the cornea of the eye to be examined E is detected by the imaging device 59 together with the anterior segment image. The processing unit 9 calculates a corneal shape parameter representing the shape of the cornea by performing a known calculation based on the keratling image.

(Target projection system 4)
The target projection system 4 presents various targets such as a fixation target and a target for subjective examination to the eye to be examined E. The light (visible light) output from the light source 41 is collimated by the collimating lens 42 and is applied to the target chart 43. The target chart 43 includes, for example, a transmissive liquid crystal panel, and displays a pattern representing the target. The light transmitted through the target chart 43 passes through the relay lenses 44 and 45, is reflected by the reflection mirror 46, passes through the dichroic mirror 68, and is reflected by the dichroic mirror 53. The light reflected by the dichroic mirror 53 passes through the objective lens 52 and is projected onto the fundus oculi Ef. The light source 41, the collimator lens 42, and the target chart 43 are integrally movable in the optical axis direction.

  When the subjective inspection is performed, the processing unit 9 controls the target chart 43 by moving the light source 41, the collimator lens 42, and the target chart 43 in the optical axis direction based on the result of the objective measurement. The processing unit 9 causes the visual target chart 43 to display the visual target selected by the examiner or the processing unit 9. Thereby, the target is presented to the subject. The subject responds to the target. In response to the input of the response content, the processing unit 9 performs further control and calculation of the subjective test value. For example, in visual acuity measurement, the processing unit 9 selects and presents the next visual target based on the response to the Landolt's ring or the like, and repeatedly performs this to determine the visual acuity value.

(Reflex measurement projection system 6, reflex measurement light reception system 7)
The reflex measurement projection system 6 and the reflex measurement light receiving system 7 are used for objective refraction measurement (reflex measurement). The reflex measurement projection system 6 projects a ring-shaped luminous flux (infrared light) for objective measurement on the fundus oculi Ef. The reflex measurement light receiving system 7 receives the return light of the ring-shaped luminous flux from the eye E to be examined.

  The reflex measurement light source 61 may be a super luminescent diode (SLD) light source which is a high luminance light source having a light emission diameter equal to or smaller than a predetermined size. The reflex measurement light source 61 is movable in the optical axis direction and disposed at the fundus conjugate position P. The ring stop 65 (specifically, the light transmitting portion) is disposed at the pupil conjugate position Q. The focusing lens 74 is movable in the optical axis direction. The focusing lens 74 may be a known variable focus lens capable of changing the focus position under the control of the main control unit 111 described later. In the optical system passing through the reflex measurement light receiving system 7, the imaging surface of the imaging element 59 is disposed at the fundus conjugate position P.

  The light output from the reflex measurement light source 61 passes through the relay lens 62 and enters the conical surface of the conical prism 63. The light incident on the conical surface is deflected and emitted from the bottom of the conical prism 63. The light emitted from the bottom of the conical prism 63 passes through the field lens 64 and passes through the light transmitting portion formed in the ring shape of the ring diaphragm 65. The light (ring-shaped light flux) that has passed through the light transmitting portion of the ring diaphragm 65 is reflected by the reflection surface of the apertured prism 66, passes through the rotary prism 67, and is reflected by the dichroic mirror 68. The light reflected by the dichroic mirror 68 is reflected by the dichroic mirror 53, passes through the objective lens 52, and is projected onto the eye E. The rotary prism 67 is used for averaging the light quantity distribution of the ring-like light flux with respect to the blood vessel and the diseased part of the fundus oculi Ef and reducing speckle noise caused by the light source.

  It is desirable that the conical prism 63 be disposed as close as possible to the pupil conjugate position Q.

  FIG. 2 schematically shows a sectional view of the field lens 64. As shown in FIG. For example, as shown in FIG. 2, a ring diaphragm 65 may be attached to the lens surface of the field lens 64 on the eye E side. In this case, for example, a light shielding film is vapor-deposited on the lens surface of the field lens 64 so as to form a ring-shaped light transmitting portion.

  Further, the reflex measurement projection system 6 may have a configuration in which the field lens 64 is omitted.

  A cross-sectional view of the conical prism 63 is schematically shown in FIG. For example, as shown in FIG. 3, the ring diaphragm 65 may be attached to the bottom surface 63 b of the conical prism 63 in which the light passing through the relay lens 62 is incident on the conical surface 63 a. In this case, for example, a light shielding film is vapor-deposited on the bottom surface 63b of the conical prism 63 so as to form a ring-shaped light transmitting portion. Also, the ring stop may be on the side of the conical surface 63 a of the conical prism 63.

  The ring diaphragm 65 may be a diaphragm in which a light transmitting portion having a shape corresponding to a predetermined measurement pattern is formed. A light transmitting portion may be formed in this stop at a position eccentric to the optical axis of the reflex measurement projection system 6. Moreover, two or more light transmission parts may be formed in the diaphragm.

  The return light of the ring-like light beam projected onto the fundus oculi Ef passes through the objective lens 52 and is reflected by the dichroic mirror 53 and the dichroic mirror 68. The return light reflected by the dichroic mirror 68 passes through the rotary prism 67, passes through the hole of the apertured prism 66, passes through the relay lens 71, is reflected by the reflection mirror 72, and is relay lens 73 and focusing lens Pass 74 The light passing through the focusing lens 74 is reflected by the reflection mirror 75, is reflected by the dichroic mirror 57, and is imaged on the imaging surface of the imaging element 59 by the imaging lens 58. The processing unit 9 calculates the refractive power value of the eye E by performing a known calculation based on the output from the imaging device 59. For example, refractive power values include spherical power, astigmatic power and astigmatic axis angle.

  Between the apertured prism 66 and the relay lens 71, a stop that limits the diameter of the light beam on the pupil is disposed. The light transmitting portion of the diaphragm is disposed at the pupil conjugate position.

  The processing unit 9 sets the reflex measurement light source 61 and the focusing lens 74 so that the fundus oculi Ef, the reflex measurement light source 61 and the imaging surface of the imaging device 59 become optically conjugate based on the calculated refractive power value. Are respectively moved in the optical axis direction. Further, the processing unit 9 moves the index unit in the optical axis direction in conjunction with the movement of the reflex measurement light source 61 and the focusing lens 74. The target unit including the light source 41, the collimator lens 42 and the target chart 43, the reflex measurement light source 61, and the focusing lens 74 may be movable in the respective optical axis directions in conjunction with each other.

<Configuration of processing system>
The configuration of the processing system of the ophthalmologic apparatus 1000 will be described. An example of the functional configuration of the processing system of the ophthalmologic apparatus 1000 is shown in FIGS. 4 and 5. FIG. 4 illustrates an example of a functional block diagram of a processing system of the ophthalmologic apparatus 1000. FIG. 5 shows an example of a functional block diagram of the arithmetic processing unit 120 of FIG.

  The processing unit 9 controls each unit of the ophthalmologic apparatus 1000. In addition, the processing unit 9 can execute various arithmetic processing. The processing unit 9 includes a processor. The functions of the processor include, for example, a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), a programmable logic device (for example, a simple programmable logic device (SPLD), a complex programmable logic device (CPLD)). , And a circuit such as an FPGA (Field Programmable Gate Array). The processing unit 9 realizes the function according to the embodiment by, for example, reading and executing a program stored in a storage circuit or a storage device.

  The processing unit 9 includes a control unit 110 and an arithmetic processing unit 120. The ophthalmologic apparatus 1000 also includes a display unit 170, an operation unit 180, and a communication unit 190.

(Control unit 110)
The control unit 110 controls each unit of the ophthalmologic apparatus 1000. Control unit 110 includes a main control unit 111 and a storage unit 112.

  The main control unit 111 performs various controls of the ophthalmologic apparatus 1000. The main control unit 111 controls the Z alignment light source 11 or the line sensor 13 of the Z alignment system 1, the XY alignment light source 21 of the XY alignment system 2, and the kerat light source of the kerat measurement system 3. As a result, the light amount of the light output from the Z alignment light source 11, the XY alignment light source 21, or the kerat ring light source is changed, or the lighting or non-lighting is switched. Further, a signal detected by the line sensor 13 is captured, and alignment control or the like based on the captured signal is performed.

  The main control unit 111 controls the light source 41 of the target projection system 4 and the target chart 43. Thereby, the light quantity of the light output from the light source 41 is changed, and lighting and non-lighting are switched. In addition, the on / off of the display of the visual targets and the fixation targets in the visual target chart 43, and the visual targets and the fixation targets are switched. In addition, the main control unit 111 can control a moving mechanism (not shown) that moves the target unit including the light source 41, the collimator lens 42, and the target chart 43 in the optical axis direction.

  The main control unit 111 controls the anterior ocular segment illumination light source 51 and the imaging device 59 of the anterior ocular segment observation system 5. Thereby, the light quantity of the light output from the anterior ocular segment illumination light source 51 is changed, and lighting and non-lighting are switched. Further, the exposure time of the imaging device 59 is changed, or the detection sensitivity is changed by controlling the gain of the amplifier included in the imaging device 59. In addition, a signal acquired by the imaging element 59 is taken in, and the formation of an image and the like are performed by the arithmetic processing unit 120.

  The main control unit 111 controls the reflex measurement light source 61 and the rotary prism 67 of the reflex measurement projection system 6 and the focusing lens 74 of the reflex measurement light receiving system 7. As a result, the light amount of the light output from the reflex measurement light source 61 is changed, and lighting and non-lighting are switched. In addition, the rotational speed of the rotary prism 67 is changed, and the on / off of the rotational operation is switched. In addition, the position of the focusing lens 74 in the optical axis direction is changed. Further, the main control unit 111 can control a moving mechanism (not shown) that moves the reflex measurement light source 61 and the focusing lens 74 in the optical axis direction. When the focusing lens 74 is a variable focus lens, the main control unit 111 can change the focus position of the focusing lens 74 by controlling the focusing lens 74.

  In this embodiment, the main control unit 111 includes a moving mechanism including a holding unit that holds a target unit including the light source 41, the collimator lens 42, and the target chart 43, the reflex measurement light source 61, and the focusing lens 74. It is possible to control The movement mechanism is provided with an actuator that generates a driving force for moving the holding member, and a transmission mechanism that transmits the driving force. The actuator is constituted by, for example, a pulse motor. The transmission mechanism is configured by, for example, a combination of gears, a rack and pinion, and the like. The main control unit 111 can move each in the optical axis direction by controlling such a moving mechanism.

  The main control unit 111 controls the target projection system 4, the anterior eye observation system 5, the reflex measurement projection system 6, the reflex measurement light receiving system, and the arithmetic processing unit 120 to execute temporary measurement twice or more, It is possible to carry out the main measurement under the measurement conditions determined by the last performed temporary measurement. The measurement conditions of the same type may be determined by each temporary measurement so that the measurement conditions converge each time the temporary measurement is repeated, or different types of measurement conditions may be determined. In this embodiment, the main measurement is performed after two temporary measurements. For example, in each temporary measurement, the light amount of light output from the reflex measurement light source 61 (the light amount of the reflex measurement light source 61), the exposure time of the imaging device 59, and the detection sensitivity of the imaging device 59 based on the obtained ring image. And at least one of the control contents for the focusing lens 74 may be determined.

  Further, the main control unit 111 performs a process of writing data in the storage unit 112 and a process of reading data from the storage unit 112.

  The storage unit 112 stores various data. As data stored in the storage unit 112, measurement information obtained by the kerat measurement system 3, measurement information obtained by the reflex measurement projection system 6 and the reflex measurement light reception system 7, an image of an image acquired by the imaging device 59 There are data, eye information etc. The subject's eye information includes information on the subject such as patient ID and name, and information on the subject's eye such as identification information of the left eye / right eye. The measurement information obtained by the kerat measurement system 3 is stored in the storage unit 112 when the kerato measurement of the eye to be examined E is performed by the ophthalmologic apparatus 1000. The measurement information obtained by the reflex measurement projection system 6 and the reflex measurement light receiving system 7 is stored in the storage unit 112 when the ophthalmologic apparatus 1000 performs reflex measurement of the eye E. The storage unit 112 may be used as a working memory for calculation processing of a corneal shape parameter and calculation processing of an eye refractive power value. The storage unit 112 also stores various programs and data for operating the ophthalmologic apparatus 1000.

(Operation processing unit 120)
The arithmetic processing unit 120 executes various arithmetic operations for obtaining parameters representing eye refractive power, such as, for example, a corneal shape parameter and an eye refractive power value. The arithmetic processing unit 120 includes an analysis unit 121.

  The analysis unit 121 analyzes a ring image (pattern image) obtained by the imaging device 59 receiving the return light of the ring-shaped light beam (ring-shaped measurement pattern) projected onto the fundus oculi Ef by the reflex measurement projection system 6 Do. For example, the analysis unit 121 obtains the barycentric position of the ring image from the brightness distribution in the image in which the obtained ring image is drawn, and obtains the brightness distribution along a plurality of scanning directions extending radially from the barycentric position. Identify the ring image from the distribution. The analysis unit 121 can determine whether the luminance (ring luminance) of the specified ring image is within a predetermined luminance range. The analysis unit 121 may determine whether the S / N ratio of the identified ring image is within a predetermined numerical range.

  The analysis unit 121 can obtain the spherical ellipse, the astigmatic power, and the astigmatic axis angle by obtaining the approximate ellipse of the specified ring image and substituting the major axis and the minor axis of the approximate ellipse into a known equation. Alternatively, the analysis unit 121 can obtain the spherical dioptric power, the astigmatic power and the astigmatic axis angle based on the specified ring image (approximate ellipse) and the control content (for example, the movement amount) for the focusing lens 74 is there. Alternatively, the analysis unit 121 can obtain the eye refractive power parameter based on the deformation and displacement of the ring image with respect to the reference pattern.

  Further, the analysis unit 121 calculates the corneal refractive power, the corneal astigmatism, and the corneal astigmatism axis angle based on the keratling image acquired by the anterior segment observation system 5. For example, the analysis unit 121 calculates the corneal curvature radius of the strong principal meridian and the weak principal meridian of the front surface of the cornea by analyzing the keratoring image, and calculates the above-described parameter based on the corneal curvature radius.

(Display unit 170, operation unit 180)
The display unit 170 receives control of the control unit 110 and displays information. The operation unit 180 is used to operate the ophthalmologic apparatus 1000 and to input information. The operation unit 180 includes various hardware keys (joysticks, buttons, switches, etc.) and / or various software keys (buttons, icons, menus, etc.) presented on the display unit 170.

(Communication unit 190)
The communication unit 190 has a function of communicating with an external device. The communication unit 190 includes a communication interface corresponding to the connection form with the external device. An example of an external device is a spectacle lens measuring device for measuring the optical properties of the lens. The spectacle lens measurement device measures the power of the spectacle lens worn by the subject and the like, and inputs this measurement data to the ophthalmic device 1000. Further, the external apparatus may be an optional ophthalmologic apparatus, an apparatus (reader) for reading information from a recording medium, an apparatus (writer) for writing information on a recording medium, or the like. Furthermore, the external device may be a hospital information system (HIS) server, a digital imaging and communication in medicine (DICOM) server, a doctor terminal, a mobile terminal, a personal terminal, a cloud server, or the like.

  In the ophthalmologic apparatus 1000, the reflex measurement light source 61 is disposed at the fundus conjugate position P, the ring diaphragm 65 is disposed at the pupil conjugate position Q, and the conical prism 63 is disposed near the pupil conjugate position Q. It becomes possible to project a ring-shaped measurement pattern with high brightness (a narrow inner diameter and a narrow outer diameter) at Ef. Therefore, the total amount of light of the measurement light flux incident on the eye E can be reduced, and the measurement pattern light flux having high luminance can be projected onto the eye E while reducing the burden on the subject. As a result, it is possible to obtain a reliable eye refractive power value. In addition, since the profile of the ring image on the fundus becomes steep, the influence of the blocking of the incident light beam on the turbid part of the lens caused by eyebrows and cataract is small, and the occurrence of measurement error can be suppressed.

  The reflex measurement light source 61 is an example of the “light source” according to the embodiment. The ring-shaped luminous flux projected onto the subject eye E by the reflex measurement projection system 6 is an example of the “pattern light” according to the embodiment. The anterior eye observation system 5, the reflex measurement projection system 6, and the reflex measurement light receiving system 7 are examples of the "optical system" according to the embodiment. The ring image is an example of the “pattern image” according to the embodiment. The ring diaphragm 65 is an example of the “diaphragm” according to the embodiment. The conical prism 63 is an example of the “deflection member” according to the embodiment.

<Operation example>
The operation of the ophthalmologic apparatus 1000 according to the embodiment will be described. An example of the operation of the ophthalmologic apparatus 1000 is shown in FIGS. FIG. 6 shows a flowchart of an operation example of the ophthalmologic apparatus 1000. FIG. 7 shows a flowchart of an operation example of step S3 of FIG. FIG. 8 shows a flowchart of an operation example of step S14 or step S20 of FIG. FIG. 9 shows a flowchart of an operation example of step S32 of FIG. FIG. 10 shows a flowchart of an operation example of step S34 of FIG. Hereinafter, it is assumed that the target unit including the light source 41, the collimator lens 42, and the target chart 43 is moved in the optical axis direction.

  First, an operation example of the ophthalmologic apparatus 1000 will be described with reference to FIG.

(S1: Alignment)
The ophthalmologic apparatus 1000 performs fixation with the light source 41 and the visual target chart 43 by the examiner performing a predetermined operation on the operation unit 180 in a state where the face of the subject is fixed to the face receiving unit (not shown). A mark is projected on the eye E to be examined and alignment is performed.

  Specifically, the main control unit 111 turns on the Z alignment light source 11, the XY alignment light source 21, and the light source 41. Furthermore, the anterior ocular segment illumination light source 51 is turned on. The kerato light source may be turned on instead of the anterior segment illumination light source. The processing unit 9 acquires an imaging signal of an anterior segment image on the imaging surface of the imaging element 59, and causes the display unit 170 to display the anterior segment image. Thereafter, the optical system shown in FIG. 1 is moved to the examination position of the eye E. The examination position is a position at which the examination of the eye E can be performed with sufficient accuracy. The eye to be examined E is disposed at the examination position through the above-mentioned alignment (alignment by the Z alignment system 1 and the XY alignment system 2 and the anterior segment observation system 5). The movement of the optical system is performed by the main control unit 111 in accordance with an operation or instruction from the user or an instruction from the main control unit 111. That is, movement of the optical system to the examination position of the eye E to be examined and preparation for performing objective measurement are performed.

  Further, the main control unit 111 moves the reflex measurement light source 61, the focusing lens 74, and the above-mentioned index unit to the position of the origin (for example, a position corresponding to 0D) along the respective optical axes.

(S2: Kerat measurement)
The main control unit 111 projects a bright spot on the eye E as a fixation target by the light source 41 and the target chart 43, and performs kerato measurement.

  That is, the main control unit 111 turns on the kerat light source. When light is output from the kertling light source, a ring-shaped luminous flux for measuring the corneal shape is projected onto the cornea of the eye to be examined E. The analysis unit 121 calculates the corneal curvature radius by performing arithmetic processing on the image acquired by the imaging device 59, and calculates the corneal refractive power, the corneal astigmatism, and the corneal astigmatism axis angle from the calculated corneal curvature radius. calculate. In the control unit 110, the calculated corneal refractive power and the like are stored in the storage unit 112. The operation of the ophthalmologic apparatus 1000 proceeds to step S3 in accordance with an instruction from the main control unit 111 or a user operation or instruction on the operation unit 180.

(S3: reflex measurement)
The main control unit 111 turns on the reflex measurement light source 61 to execute reflex measurement. Details of step S3 will be described later.

  In the control unit 110, the storage unit 112 stores the movement amount of the focusing lens 74 after the reflex measurement in step S3, the spherical power calculated from the shape of the ring image, and the like. The operation of the ophthalmologic apparatus 1000 proceeds to step S4 in accordance with an instruction from the main control unit 111 or a user operation or instruction on the operation unit 180. Thus, the operation of the ophthalmologic apparatus 1000 ends (end).

[Ref measurement]
As shown in FIGS. 7 to 10, the ophthalmologic apparatus 1000 executes the reflex measurement in step S3 of FIG.

(S11: Initialization of temporary measurement conditions)
The main control unit 111 sets the light amount of light (light amount of the reflex measurement light source 61) output from the reflex measurement light source 61, and the exposure time and detection sensitivity of the imaging device 59 to initial values prior to the first temporary measurement. Do.

(S12: temporary measurement (first time))
The main control unit 111 causes the first temporary measurement to be performed in a state in which the focusing lens is disposed at the reference position (0D position). Specifically, the main control unit 111 turns on the reflex measurement light source 61 to project a ring-shaped luminous flux on the reflex measurement projection system 6 with respect to the fundus oculi Ef, and an imaging device as a return light of the ring-shaped luminous flux from the fundus oculi Ef Make 59 receive light. As a result, an image in which a ring image based on the ring-like light beam projected onto the fundus oculi Ef is drawn is obtained.

(S13: Is the brightness correct?)
The main control unit 111 causes the analysis unit 121 to perform a ring brightness check on the ring image obtained from the light reception result of the imaging device 59 in step S12. The analysis unit 121 obtains the barycentric position of the ring image from the brightness distribution in the image obtained by the imaging device 59, obtains the brightness distribution along a plurality of scanning directions extending radially from the barycentric position, and obtains the ring image from this brightness distribution. Identify The analysis unit 121 determines whether the brightness of the ring image is appropriate by determining whether the brightness of the specified ring image is within a predetermined brightness range. When it is determined that the luminance of the ring image is within the predetermined luminance range (S13: Y), the operation of the ophthalmologic apparatus 1000 proceeds to step S15. When it is determined that the luminance of the ring image is not within the predetermined luminance range (S13: N), the operation of the ophthalmologic apparatus 1000 proceeds to step S14.

(S14: Measurement condition change control)
When it is determined in step S13 that the luminance of the ring image is not within the predetermined luminance range (S13: N), the main control unit 111 executes measurement condition change control. In the measurement condition change control in step S14, the light intensity of the reflex measurement light source 61, the exposure time of the imaging device 59, and the detection sensitivity of the imaging device 59 are changed such that the luminance of the acquired ring image is changed. Details of step S14 will be described later.

  When step S14 ends, the operation of the ophthalmologic apparatus 1000 proceeds to step S12. That is, image acquisition in step S12 (first tentative measurement) and the ring image luminance check in step S13 are repeated until the luminance of the ring image falls within the predetermined luminance range.

(S15: Calculate temporary refractive power)
When it is determined in step S13 that the luminance of the ring image is within the predetermined luminance range (S13: Y), the main control unit 111 determines the temporary refracting power value (equivalent spherical refraction based on the image acquired in step S12). The analysis unit 121 is made to calculate the force value). As described above, the analysis unit 121 obtains an approximate ellipse of the ring image specified in the acquired image, and calculates a temporary refractive power value from the approximate ellipse.

(S16: Focus control)
Next, based on the eye refractive power value obtained in step S15, the main control unit 111 controls the content of control for the actuator that moves the focusing lens 74 so that the ring image acquired in step S12 is in focus. decide. In this embodiment, the main control unit 111 determines the control content of the actuator corresponding to the movement direction and the movement amount of the focusing lens 74 in the optical axis direction. For example, correspondence information in which the eye refractive power value and the movement direction and movement amount of the focusing lens 74 in the optical axis direction are associated is stored in advance in the storage unit 112, and the main control unit 111 stores the information in the storage unit 112. The control content of the actuator is determined by referring to the corresponding information.

  The main control unit 111 arranges the focusing lens 74 at a position corresponding to the eye refractive power value obtained in step S15 by controlling the actuator based on the determined control content.

  When the focusing lens 74 is a focus variable lens, the main control unit 111 can similarly determine the control content of the focusing lens 74. That is, correspondence information in which the eye refractive power value and the control content for the focusing lens 74 are associated is stored in advance in the storage unit 112, and the main control unit 111 refers to the correspondence information stored in the storage unit 112. By doing this, the control content for the focusing lens 74 is determined. The main control unit 111 can change the focus position to a desired position by controlling the focusing lens 74 based on the determined control content. At the same time, the fixation target unit including the light source 61, the light source 41, the collimator lens 42, and the target chart 42 is moved. This movement may be driven by a common actuator or may be driven individually by separate actuators, which may be driven together.

(S17: Determination of the next temporary measurement condition)
Next, the main control unit 111 sets measurement conditions for performing the second temporary measurement. This measurement condition may be the measurement condition at the time when step S16 ends. In addition, the main control unit 111 may specify new measurement conditions from the measurement conditions at the time when step S16 ends. Since the brightness (brightness) of the ring image changes with the movement amount of the focusing lens 74, the light amount of the light source 61 may be changed based on the movement amount. The relationship between the amount of movement of the focusing lens 74 and the amount of light of the light source 61 may be derived by an equation or may be stored as table information. The equation may be a linear expression or a quadratic expression derived from an experimental result or the like.

(S18: temporary measurement (second time))
The main control unit 111 causes the second temporary measurement to be performed. Step S18 is substantially the same as step S12.

(S19: Is the brightness correct?)
The main control unit 111 causes the analysis unit 121 to execute the brightness check of the ring image for the ring image obtained in step S18, as in step S13. The luminance range in the ring luminance check in step S19 may be the same as or different from the luminance range in the luminance check of the ring image in step S13.

  When it is determined that the luminance of the ring image is within the predetermined luminance range (S19: Y), the operation of the ophthalmologic apparatus 1000 proceeds to step S21. When it is determined that the luminance of the ring image is not within the predetermined range (S19: N), the operation of the ophthalmologic apparatus 1000 proceeds to step S20.

(S20: Measurement condition change control)
When it is determined in step S19 that the luminance of the ring image is not within the predetermined range (S19: N), the main control unit 111 executes measurement condition change control. The measurement condition change control in step S20 is the same as step S14.

  When step S20 ends, the operation of the ophthalmologic apparatus 1000 proceeds to step S18. That is, the image acquisition (second tentative measurement) in step S18 and the ring image brightness check in step S19 are repeated until the brightness of the ring image falls within the predetermined range.

(S21: Calculate temporary refractive power value)
When it is determined in step S19 that the luminance of the ring image is within the predetermined luminance range (S19: Y), the main control unit 111 determines the ring specified in the image acquired in step S18, as in step S15. Based on the image (for example, the shape of the ring image and the amount of movement of the focusing lens 74 with respect to the ring image), the temporary refractive power value is calculated by the analysis unit 121.

(S22: Focus control)
As in step S16, the main control unit 111 controls the actuator for moving the focusing lens 74 such that the ring image obtained in step S18 is in focus based on the eye refractive power value obtained in step S21. Determine the control content.

  The main control unit 111 arranges the focusing lens 74 at a position corresponding to the temporary refractive power value obtained in step S21 by controlling the actuator based on the determined control content.

(S23: Cloud control)
Next, the main control unit 111 sets measurement conditions for performing the main measurement. This measurement condition may be the measurement condition at the time when step S22 ends. In addition, the main control unit 111 may specify new measurement conditions from the measurement conditions at the time when step S22 ends. In particular, when the movement amount of the focusing lens 74 is large, the change in the luminance of the ring image may be large. Therefore, a new measurement condition may be obtained in consideration of this change.

  Subsequently, the main control unit 111 executes control for causing the eye to be examined E1 to be foggy. Specifically, the main control unit 111 moves the solid index unit including the light source 41, the collimator lens 42, and the target chart 53 by a predetermined movement amount by controlling the above-described actuator. In the configuration in which the light source 61 and the focusing lens 74 are integrally driven, they also move simultaneously.

(S24: main measurement)
The main control unit 111 executes the main measurement. Specifically, the main control unit 111 turns on the reflex measurement light source 61 to project a ring-shaped luminous flux on the reflex measurement projection system 6 with respect to the fundus oculi Ef, and an imaging device as a return light of the ring-shaped luminous flux from the fundus oculi Ef Make 59 receive light. As a result, an image in which a ring image based on the ring-like light beam projected onto the fundus oculi Ef is drawn is obtained.

(S25: Calculate eye refractive power)
The main control unit 111 obtains an approximate ellipse of the ring image specified in the image acquired in step S 24, and analyzes the spherical power, the astigmatic power and the astigmatic axis angle from the movement amount of the focusing lens 74 and this approximate ellipse. Make it calculate. This is the end of the operation of the ophthalmologic apparatus 1000 (end).

[Measurement condition change control]
The ophthalmologic apparatus 1000 executes step S14 or step S20 of FIG. 7 as shown in FIGS. In addition, any one of step S14 and step S20 may be performed as shown in FIGS.

(S31: High brightness?)
The main control unit 111 determines whether the luminance of the ring image is high. When the luminance of the ring image is equal to or higher than the upper limit value of the predetermined luminance range, the main control unit 111 determines that the luminance of the ring image is high. When it is determined that the luminance of the ring image is high (S31: Y), the operation of the ophthalmologic apparatus 1000 proceeds to step S32. When it is not determined that the luminance of the ring image is high (S31: N), the operation of the ophthalmologic apparatus 1000 proceeds to step S33.

(S32: brightness reduction control)
When it is determined in step S31 that the luminance of the ring image is high (S31: Y), the main control unit 111 executes luminance reduction control. In the luminance reduction control in step S32, the light amount of the reflex measurement light source 61 is changed, or the exposure time of the imaging device 59 and the detection sensitivity of the imaging device 59 are changed so that the luminance of the acquired ring image is reduced. Details of step S32 will be described later.

  When step S32 ends, the operation of step S14 or step S20 of the ophthalmologic apparatus 1000 ends (end).

(S33: Low brightness?)
When it is not determined in step S31 that the luminance of the ring image is high (S31: N), the main control unit 111 determines whether the luminance of the ring image is low. When the luminance of the ring image is equal to or less than the lower limit value of the predetermined luminance range, the main control unit 111 determines that the luminance of the ring image is low. When it is determined that the luminance of the ring image is low (S33: Y), the operation of the ophthalmologic apparatus 1000 proceeds to step S34. When it is not determined that the luminance of the ring image is low (S33: N), the operation of step S14 or step S20 of the ophthalmologic apparatus 1000 ends (end).

(S34: Brightness increase control)
When it is determined in step S33 that the luminance of the ring image is low (S33: Y), the main control unit 111 executes luminance increase control. In the brightness increase control in step S34, the light amount of the reflex measurement light source 61 is changed, or the exposure time of the image sensor 59, the detection sensitivity of the image sensor 59, and the focusing lens 74 are increased. Movement amount is changed. Details of step S34 will be described later.

  When step S34 ends, the operation of step S14 or step S20 of the ophthalmologic apparatus 1000 ends (end).

[Brightness reduction control]
The ophthalmologic apparatus 1000 executes the brightness reduction control in step S32 of FIG. 8 as shown in FIG. In the luminance reduction control according to the embodiment, the first detection sensitivity for lowering the luminance of the apparent ring image by lowering the detection sensitivity of the imaging device 59 based on the luminance (that is, the amount to be reduced) of the obtained ring image. After the control is performed, the first exposure time control for reducing the luminance of the ring image is performed by shortening the exposure time of the imaging element 59. Furthermore, after the first exposure time control, the first light quantity control is performed to lower the luminance of the ring image by reducing the light quantity of the reflex measurement light source 61.

  For example, in the luminance reduction control, after the first detection sensitivity control for reducing the apparent luminance of the ring image within the predetermined first luminance range is performed, the second luminance range is within the upper limit of the lower limit of the first luminance range. The first exposure time control is performed to reduce the apparent brightness of the ring image. Furthermore, after the first exposure time control, the first light quantity control is performed to lower the luminance of the ring image in the third luminance range in which the upper limit is equal to or less than the lower limit of the second luminance range.

(S41: Determine the amount of decrease in luminance)
First, the main control unit 111 determines the amount of decrease in the luminance of the ring image. The amount of reduction may be a predetermined amount.

  The amount of decrease may be an amount corresponding to the saturation light amount of the imaging device 59 or the saturation amount due to A / D conversion. In this case, the main control unit 111 causes the analysis unit 121 to calculate the reduction amount of the luminance of the ring image. The analysis unit 121 can predict the brightness of the ring image after the movement of the focusing lens 74, and can obtain the decrease in brightness from the predicted value. For example, the analysis unit 121 determines the difference between the luminance of the ring image and the upper limit value of the luminance range in step S31, the light amount of the reflex measurement light source 61, the exposure time of the image sensor 59, or the control amount for the detection sensitivity of the image sensor 59. And the amount of movement of the focusing lens 74 determined by the temporary measurement to specify the post-movement luminance.

(S42: Detection sensitivity TH TH1?)
Next, the main control unit 111 identifies the detection sensitivity (gain) of the imaging element 59, and determines whether the identified detection sensitivity is equal to or greater than the first threshold TH1. The main control unit 111 may specify the detection sensitivity from the control content of the image sensor 59, or may specify the detection sensitivity from the content set for the image sensor 59. When it is determined that the detection sensitivity is equal to or higher than the first threshold TH1 (S42: Y), the operation of the ophthalmologic apparatus 1000 proceeds to step S43. When it is determined that the detection sensitivity is less than the first threshold TH1 (S42: N), the operation of the ophthalmologic apparatus 1000 proceeds to step S44.

(S43: Decrease the detection sensitivity)
When it is determined in step S42 that the detection sensitivity is equal to or higher than the first threshold TH1 (S42: Y), the main control unit 111 controls the imaging element 59 to lower the detection sensitivity. The main control unit 111 can lower the detection sensitivity by a predetermined amount or a predetermined ratio.

  As described above, the first detection sensitivity control is performed in step S42 and step S43. When step S43 is completed, the operation of step S32 of the ophthalmologic apparatus 1000 ends (end).

(S44: Exposure time TH TH2?)
When it is determined in step S42 that the detection sensitivity is less than the first threshold TH1 (S42: N), the main control unit 111 identifies the exposure time of the imaging element 59, and the identified exposure time is the second threshold TH2 It is determined whether it is above or not. The main control unit 111 may specify the exposure time from the control content for the imaging device 59, or may specify the exposure time from the content set for the imaging device 59.

  When the exposure time becomes short, it is possible to suppress the occurrence of measurement error caused by the movement of the eye E to be examined. However, in order to obtain the effect of averaging the light amount distribution by the rotary prism 67, it is desirable that the exposure time of the image pickup device 59 be the time (lower limit time) or more at which the rotary prism 67 rotates a predetermined number of times. Therefore, the second threshold TH2 may be a lower limit time corresponding to the rotational speed of the rotary prism 67.

  When it is determined that the exposure time of the imaging element 59 is equal to or greater than the second threshold TH2 (S44: Y), the operation of the ophthalmologic apparatus 1000 proceeds to step S45. When it is determined that the exposure time of the imaging element 59 is less than the second threshold TH2 (S44: N), the operation of the ophthalmologic apparatus 1000 proceeds to step S46.

(S45: shorten the exposure time)
When it is determined in step S44 that the exposure time is equal to or greater than the second threshold TH2 (S44: Y), the main control unit 111 controls the imaging element 59 to shorten the exposure time. The main control unit 111 can shorten the exposure time by a predetermined amount or a predetermined ratio.

  Thus, the first exposure time control is performed in step S44 and step S45. When step S45 is completed, the operation of step S32 of the ophthalmologic apparatus 1000 ends (end).

(S46: Light quantity TH TH3?)
When it is determined in step S44 that the exposure time is less than the second threshold TH2 (S44: N), the main control unit 111 identifies the light quantity of the reflex measurement light source 61, and the identified light quantity is equal to or more than the third threshold TH3. It is determined whether the The main control unit 111 may specify the light amount from the control content for the reflex measurement light source 61, or may specify the light amount from the contents set in the reflex measurement light source 61.

  When it is determined that the light amount of the reflex measurement light source 61 is equal to or greater than the third threshold TH3 (S46: Y), the operation of the ophthalmologic apparatus 1000 proceeds to step S47. When it is determined that the light amount of the reflex measurement light source 61 is less than the third threshold TH3 (S46: N), the operation of the ophthalmologic apparatus 1000 proceeds to step S48.

(S47: Decrease the light amount)
When it is determined in step S46 that the light quantity of the reflex measurement light source 61 is the third threshold TH3 or more (S46: Y), the main control unit 111 controls the reflex measurement light source 61 to reduce the light quantity. The main control unit 111 can reduce the light amount by a predetermined amount or a predetermined ratio.

  As described above, the first light amount control is performed in step S46 and step S47. When step S47 is completed, the operation of step S32 of the ophthalmologic apparatus 1000 ends (end).

(S48: Error processing)
When it is determined in step S46 that the light amount of the reflex measurement light source 61 is less than the third threshold TH3 (S46: N), the main control unit 111 executes predetermined error processing. The predetermined error process includes an error display process on the display unit 170 and the like. If it is determined that control of the detection sensitivity of the image sensor 59, the exposure time, and the light amount of the reflex measurement light source 61 is impossible even though the luminance of the ring image is determined to be high, error processing is performed. When step S48 is completed, the reflex measurement by the ophthalmologic apparatus 1000 ends (end).

  As described above, since the first detection sensitivity control is preferentially executed by repeatedly executing the luminance reduction control, the first exposure time control is executed to supplement the first detection sensitivity control. Finally, a first detection sensitivity control is performed to supplement the first exposure time control.

  The first detection sensitivity control has less influence on the measurement environment as compared with the first exposure time control and the first light amount control. On the other hand, although the first exposure time control is advantageous to the movement of the eye E as described above, the effect of the rotary prism 67 can not be obtained. Therefore, by performing the first exposure time control after the first detection sensitivity control, it is possible to suppress a decrease in measurement accuracy of the reflex measurement while obtaining an effect by the rotary prism 67 even when the luminance of the ring image is high. become. In addition, since the first light amount control is performed after the first exposure time control, it is possible to minimize the influence on the measurement environment.

[Brightness control]
The ophthalmologic apparatus 1000 executes the brightness increase control in step S34 of FIG. 8 as shown in FIG. In the luminance increase control according to the embodiment, the second light amount control is performed to increase the luminance of the ring image by increasing the light amount of the reflex measurement light source 61 based on the luminance (that is, the amount to be increased) of the obtained ring image. After that, the second exposure time control is performed to increase the apparent brightness of the ring image by lengthening the exposure time of the imaging device 59. Furthermore, after the second exposure time control, the second detection sensitivity control is performed to increase the apparent brightness of the ring image by increasing the detection sensitivity of the imaging device 59.

  For example, in the brightness increase control, after the second light amount control for increasing the brightness of the ring image within the predetermined fourth brightness range is performed, the ring image is generated within the fifth brightness range where the lower limit is equal to or higher than the upper limit of the fourth brightness range. A second exposure time control is performed to increase the brightness of. Furthermore, after the second exposure time control, a second detection sensitivity control is performed to increase the brightness of the ring image in the sixth brightness range in which the lower limit is equal to or higher than the upper limit of the fifth brightness range.

(S51: Determine the brightness increase amount)
First, the main control unit 111 determines the amount of increase in the luminance of the ring image. The amount of increase may be a predetermined amount.

  Further, the main control unit 111 may cause the analysis unit 121 to calculate the increase amount of the luminance of the ring image. For example, the analysis unit 121 determines the difference between the luminance of the ring image and the lower limit value of the luminance range in step S33, the light amount of the reflex measurement light source 61, the exposure time of the imaging device 59, or the control amount for the detection sensitivity of the imaging device 59. The amount of increase may be determined based on the amount of movement of the focusing lens 74.

(S52: Light quantity ≦ TH4?)
Next, the main control unit 111 identifies the light amount of the reflex measurement light source 61, and determines whether the identified light amount is equal to or less than the fourth threshold TH4. It is desirable that the fourth threshold TH4 be a light quantity in consideration of the visibility of the measurement pattern image by the subject and the safety of the subject. When it is determined that the light amount is equal to or less than the fourth threshold (S52: Y), the operation of the ophthalmologic apparatus 1000 proceeds to step S53. When it is determined that the light amount exceeds the fourth threshold TH4 (S52: N), the operation of the ophthalmologic apparatus 1000 proceeds to step S54.

(S53: Increase the light intensity)
When it is determined in step S52 that the light amount is equal to or less than the fourth threshold TH4 (S52: Y), the main control unit 111 controls the reflex measurement light source 61 to increase the light amount. The main control unit 111 can reduce the light amount by a predetermined amount or a predetermined ratio.

  As described above, the second light amount control is performed in step S52 and step S53. When step S53 is completed, the operation of step S34 of the ophthalmologic apparatus 1000 ends (end).

(S54: Exposure time TH TH5?)
When it is determined in step S52 that the light amount exceeds the fourth threshold TH4 (S52: N), the main control unit 111 identifies the exposure time of the imaging element 59, and the identified exposure time is equal to or less than the fifth threshold TH5. Determine if there is.

  When the exposure time becomes long, measurement errors due to the movement of the eye E are likely to occur. Therefore, the fifth threshold TH5 may be a time previously determined as a time in which the movement of the eye to be examined E does not occur.

  When it is determined that the exposure time of the imaging element 59 is less than or equal to the fifth threshold TH5 (S54: Y), the operation of the ophthalmologic apparatus 1000 proceeds to step S55. When it is determined that the exposure time of the imaging element 59 exceeds the fifth threshold TH5 (S54: N), the operation of the ophthalmologic apparatus 1000 proceeds to step S56.

(S55: Increase the exposure time)
When it is determined in step S54 that the exposure time is equal to or less than the fifth threshold TH5 (S54: Y), the main control unit 111 controls the imaging element 59 to extend the exposure time. The main control unit 111 can lengthen the exposure time by a predetermined amount or a predetermined ratio.

  Thus, the second exposure time control is performed in step S54 and step S55. When step S55 is completed, the operation of step S34 of the ophthalmologic apparatus 1000 ends (end).

(S56: detection sensitivity TH TH6?)
When it is determined in step S54 that the exposure time exceeds the fifth threshold TH5 (S54: N), the main control unit 111 identifies the detection sensitivity of the imaging element 59, and the identified detection sensitivity is equal to or less than the sixth threshold TH6. It is determined whether the

  When it is determined that the detection sensitivity of the imaging element 59 is less than or equal to the sixth threshold TH6 (S56: Y), the operation of the ophthalmologic apparatus 1000 proceeds to step S57. When it is determined that the detection sensitivity of the imaging element 59 exceeds the sixth threshold TH6 (S56: N), the operation of the ophthalmologic apparatus 1000 proceeds to step S58.

(S57: Increase detection sensitivity)
When it is determined in step S56 that the detection sensitivity of the imaging device 59 is equal to or less than the sixth threshold TH6 (S56: Y), the main control unit 111 controls the imaging device 59 to increase the detection sensitivity. The main control unit 111 can increase the detection sensitivity at a predetermined amount or a predetermined ratio.

  Thus, the second detection sensitivity control is performed in step S56 and step S57. When step S57 is completed, the operation of step S34 of the ophthalmologic apparatus 1000 ends (end).

(S58: Execution of focus control?)
When it is determined in step S56 that the detection sensitivity of the imaging device 59 exceeds the sixth threshold TH6 (S56: N), the main control unit 111 determines whether or not to execute focusing control by the focusing lens 74. . The main control unit 111 can determine whether or not to execute focusing control based on the control content for the focusing lens 74 (actuator) and the position of the focusing lens 74. When it is determined that the focusing control by the focusing lens 74 is to be performed (S58: Y), the operation of the ophthalmologic apparatus 1000 proceeds to step S59. When it is determined that the focusing control by the focusing lens 74 is not to be performed (S58: N), the operation of the ophthalmologic apparatus 1000 proceeds to step S60.

(S59: Focus control)
When it is determined in step S58 that focusing control by the focusing lens 74 is to be performed (S58: Y), the main control unit 111 moves the focusing lens 74 by a predetermined movement amount by controlling the actuator. The main control unit 111 can repeat the control of step S59 while changing the moving direction so as to increase the luminance of the ring image. When step S59 is completed, the operation of step S34 of the ophthalmologic apparatus 1000 ends (end).

(S60: error processing)
When it is determined in step S58 that the focusing control by the focusing lens 74 is not to be performed (S58: N), the main control unit 111 executes a predetermined error processing. The predetermined error process includes an error display process on the display unit 170 and the like. Error processing when it is determined that control of the detection sensitivity of the image sensor 59, the exposure time, the light amount of the reflex measurement light source 61, and the focusing lens 74 is impossible although the luminance of the ring image is determined to be low. Is executed. When step S60 is completed, the reflex measurement by the ophthalmologic apparatus 1000 ends (end).

  As described above, by repeatedly executing the brightness increase control, after the second light amount control is preferentially performed, the second exposure time control is performed to supplement the second light amount control. Then, the second detection sensitivity control is executed to supplement the second exposure time control, and finally the focusing control is executed to supplement the second detection sensitivity control.

  If the light amount of the reflex measurement light source 61 is increased by the second light amount control, the ring-shaped light beam projected onto the eye E may be visually recognized by the subject, and the subject may gaze closely to make fog difficult. Therefore, after the light amount is increased to a certain extent by the second light amount control, the exposure time is controlled by the second exposure time control, so that the measurement pattern is less likely to be recognized by the subject, cloudiness is facilitated, and measurement is performed. It becomes possible to prevent the occurrence of an error.

  Also, the execution of the second exposure time control means that the measurement time is prolonged. The second detection sensitivity control may amplify the noise component and degrade the image quality. Therefore, by performing the second exposure time control after the second light quantity control, it is possible to avoid prolongation of the measurement time. By performing the second detection sensitivity control after the second exposure time control, it is possible to suppress the deterioration of the image quality as much as possible.

  In addition, in the brightness reduction control shown in FIG. 9 or the brightness increase control shown in FIG. 10, in order to shorten the measurement time, priority is given to detection sensitivity control over exposure time control or only detection sensitivity control is performed. It is also good. Moreover, step S58 and step S59 in FIG. 10 may not be performed in step S14 (first tentative measurement) in FIG. 7, but may be performed only in step S20 (second tentative measurement) in FIG. 7.

  Step S14 is an example of the “first measurement condition determining step” according to the embodiment. Step S20 is an example of the “second measurement condition determining step” according to the embodiment. Step S23 is an example of the "fog control step" according to the embodiment. Step S24 is an example of the "measurement step" according to the embodiment.

  Step S31 is an example of the "first determination step" according to the embodiment. Step S42 is an example of the "second determination step" according to the embodiment. Step S43 is an example of the "first detection sensitivity control step" according to the embodiment. Step S44 is an example of the "third determination step" according to the embodiment. Step S45 is an example of the “first exposure time control step” according to the embodiment. Step S46 is an example of the "fourth determination step" according to the embodiment. Step S47 is an example of the "first light amount control step" according to the embodiment.

  Step S33 is an example of the "fifth determination step" according to the embodiment. Step S52 is an example of the "sixth determination step" according to the embodiment. Step S53 is an example of the “second light amount control step” according to the embodiment. Step S54 is an example of the "seventh determination step" according to the embodiment. Step S55 is an example of the “second exposure time control step” according to the embodiment. Step S56 is an example of the "eighth determination step" according to the embodiment. Step S57 is an example of the "second detection sensitivity control step" according to the embodiment.

[Modification]
The configuration of the optical system of the ophthalmologic apparatus 1000 according to the embodiment is not limited to the configuration shown in FIG.

  FIG. 11 shows a configuration example of an optical system of an ophthalmologic apparatus according to a modification of the embodiment. In FIG. 11, the same parts as in FIG. 1 are given the same reference numerals, and the description will be omitted as appropriate.

  The configuration of the ophthalmologic apparatus 1000a according to the modification is different from the configuration of the ophthalmologic apparatus 1000 in that a reflex measurement projection system 6a is provided instead of the reflex measurement projection system 6. The configuration of the reflex measurement projection system 6a is different from that of the reflex measurement projection system 6 in that a ring lens 69 is provided instead of the conical prism 63 and the field lens 64. The ring lens 69 includes a central region formed as a light shielding region, and a lens portion formed in a ring shape around the central region. The ring lens 69 functions as an optical element in which a field lens and a conical prism are combined.

  In the present modification, it is desirable that the ring lens 69 be disposed at a position as close as possible to the pupil conjugate position Q while avoiding enlargement of the reflex measurement projection system 6a.

  FIG. 12 schematically shows a cross-sectional view of the ring lens 69. As shown in FIG. For example, as shown in FIG. 12, a ring diaphragm 65 is attached to the lens surface of the ring lens 69 on the eye E side.

  Since the operation of the ophthalmologic apparatus 1000a according to the present modification is the same as that of the embodiment, the detailed description will be omitted.

  Also in this modification, as in the embodiment, the amount of light incident on the eye to be examined E can be reduced, and a pattern having a narrow line width and high luminance can be projected on the eye to be examined E. Therefore, it is possible to obtain a highly reliable eye refractive power value while reducing the burden on the subject. In addition, since a thin ring-shaped luminous flux can be made incident on the pupil, it is possible to suppress the occurrence of measurement error with little influence due to the interception of the incident luminous flux in the turbid part of the lens caused by eyebrows and cataracts. .

[Operation / effect]
The operation and effects of the ophthalmologic apparatus according to the embodiment or the modification will be described.

  The ophthalmologic apparatus (1000, 1000a) according to the embodiment includes an optical system (an anterior segment observation system 5, a reflex measurement projection system 6, a reflex measurement projection system 6a, a reflex measurement light reception system 7), an analysis unit 121, and a control unit. And (110, main control unit 111). The optical system projects pattern light (ring-like light flux) based on light from the light source (reflex measurement light source 61) onto the eye to be examined (E), and the focal position can change the return light of the pattern light from the eye Light is received by the imaging device (59) through the focusing lens (74). The analysis unit calculates an eye refractive power value of the subject's eye based on the pattern image (ring image) obtained by the imaging device. The control unit is a first measurement condition including at least one of the light intensity of the light source, the exposure time of the imaging device, the detection sensitivity of the imaging device, and the control content for the focusing lens based on the first pattern image obtained by the imaging device. To determine a second measurement condition including at least one of light intensity, exposure time, detection sensitivity, and control content based on a second pattern image obtained by the imaging device under the first measurement condition, and (2) The analysis unit is made to calculate the eye refractive power value based on the third pattern image obtained by the imaging device in a state in which the subject's eye is clouded under the measurement conditions.

  According to such a configuration, the temporary measurement is performed to determine the first measurement condition, and the temporary measurement is performed again under the determined first measurement condition to determine the second measurement condition. Since the eye refractive power value is obtained below, even when the brightness of the pattern image is high, it is possible to measure the eye refractive power with higher accuracy than in the prior art.

  In the ophthalmologic apparatus according to the embodiment, the light source is disposed so as to be optically substantially conjugate with the fundus (Ef) of the eye to be examined, and the optical system is optically substantially conjugate to the pupil of the eye to be examined ( A diaphragm (ring diaphragm 65) disposed in Q) and formed with a light transmitting portion for transmitting light from the light source, and a deflection member (conical prism 63, ring lens 69) for deflecting the light from the light source and guiding it to the light transmitting portion And light may be projected onto the subject's eye as pattern light.

  According to such a configuration, it is possible to project thin pattern light (with narrow inner diameter and outer width) on the fundus, so that the pattern obtained by projecting high-brightness pattern light can be obtained. It becomes possible to improve the analysis accuracy of the image. As a result, it is possible to measure the eye refractive power with higher accuracy than in the prior art by performing a pattern image with high luminance and performing a plurality of temporary measurements.

  Further, in the ophthalmologic apparatus according to the embodiment, the control unit executes the first luminance reduction control (step S14, step S32) when the luminance of the first pattern image is high, and the first part when the luminance of the first pattern image is low. The brightness increase control (step S14, step S34) is executed, and the second brightness decrease control (step S20, step S32) is executed when the brightness of the second pattern image is high, and the brightness of the second pattern image is low The brightness increase control (step S20, step S34) may be executed.

  According to such a configuration, since the first measurement condition and the second measurement condition are determined so that the brightness of the pattern image falls within the predetermined brightness range, even if the brightness of the pattern image is high, the measurement is performed. It becomes possible to measure the eye refractive power with higher accuracy than before without lowering the accuracy.

  In the ophthalmologic apparatus according to the embodiment, at least one of the first luminance reduction control and the second luminance reduction control is a first detection sensitivity that lowers the luminance of the pattern image by lowering the detection sensitivity based on the luminance of the pattern image. After the control (step S43), first exposure time control (step S45) may be performed to reduce the brightness of the pattern image by shortening the exposure time.

  According to such a configuration, when the brightness of the pattern image is high, it is possible to suppress the decrease in measurement accuracy without significantly affecting the measurement environment.

  In the ophthalmologic apparatus according to the embodiment, at least one of the first luminance reduction control and the second luminance reduction control reduces the luminance of the pattern image by reducing the light amount after the first exposure time control (step S45). One light quantity control (step S47) may be performed.

  According to such a configuration, when the brightness of the pattern image is high, it is possible to minimize the influence on the measurement environment while suppressing the occurrence of the measurement error caused by the movement of the eye to be examined.

  Further, in the ophthalmologic apparatus according to the embodiment, the optical system includes the rotary prism (67) disposed in the optical path of the pattern light, and the first exposure time control is at least the lower limit time defined by the rotational speed of the rotary prism. The exposure time may be shortened to

  According to such a configuration, it is possible to suppress the decrease in measurement accuracy while obtaining the effect of averaging the light amount distribution by the rotary prism.

  In the ophthalmologic apparatus according to the embodiment, at least one of the first luminance increase control and the second luminance increase control is exposed after the second light amount control (step S53) for increasing the luminance of the pattern image by increasing the light amount. A second exposure time control (step S55) may be performed to increase the brightness of the pattern image by lengthening the time.

  According to such a configuration, it is possible to facilitate fixation of the eye to be examined without the pattern light being visually recognized by the subject and to prevent a decrease in measurement accuracy.

  In the ophthalmologic apparatus according to the embodiment, at least one of the first brightness increase control and the second brightness increase control increases the brightness of the pattern image by increasing the detection sensitivity after the second exposure time control (step S55). The second detection sensitivity control (step S57) may be performed.

  According to such a configuration, it is possible to avoid the prolongation of the measurement time and to suppress the deterioration of the image quality caused by the amplification of the noise component as much as possible.

  Further, in the ophthalmologic apparatus according to the embodiment, the pattern light may be ring-shaped light.

  According to such a configuration, even when the luminance of the ring image based on the ring-shaped light is high, it is possible to measure the eye refractive power with higher accuracy than conventional.

  Further, in the control method of the ophthalmologic apparatus according to the embodiment, pattern light (ring light flux) based on light from the light source (reflex measurement light source 61) is projected onto the eye to be examined (E), and the pattern light is returned from the eye This is a method for measuring the refractive power of an eye to be examined by receiving light at the imaging device (59) through a focusing lens (74) whose focal position can be changed. The control method of the ophthalmologic apparatus includes a first measurement condition step (step S14), a second measurement condition step (step S20), a fog control step (step S23), and a measurement step (step S24). The first measurement condition step includes at least one of the light amount of the light source, the exposure time of the imaging device, the detection sensitivity of the imaging device, and the control content for the focusing lens based on the first pattern image obtained by the imaging device. Determine the first measurement condition. The second measurement condition determining step is a second measurement condition including at least one of light amount, exposure time, detection sensitivity, and control content based on a second pattern image obtained by the imaging device under the first measurement condition. Decide. The fog control step fogs the subject eye under the second measurement condition. In the measurement step, the refractive power is measured in a state of fogging the eye to be examined in the fog control step.

  According to such a configuration, the first measurement condition is determined in the first measurement condition determination step, and the second measurement condition is determined in the second measurement condition determination step under the determined first measurement condition. Since the eye refractive power value is acquired under the measurement conditions, even when the brightness of the pattern image is high, it becomes possible to measure the eye refractive power with higher accuracy than in the prior art.

  In the control method of the ophthalmologic apparatus according to the embodiment, at least one of the first measurement condition determination step and the second measurement condition determination step includes a first determination step (step S31) and a second determination step (step S42). , First detection sensitivity control step (step S43), third determination step (step S44), first exposure time control step (step S45), fourth determination step (step S46), and first light amount control step And (Step S47) may be included. The first determination step determines whether the brightness of the pattern image is high. The second determination step determines whether the detection sensitivity is equal to or higher than a first threshold (TH1) when it is determined that the luminance is high in the first determination step. The first detection sensitivity control step reduces the detection sensitivity when it is determined in the second determination step that the detection sensitivity is equal to or higher than a first threshold. In the third determination step, when it is determined in the second determination step that the detection sensitivity is less than the first threshold, it is determined whether the exposure time is equal to or greater than a second threshold (TH2). The first exposure time control step shortens the exposure time when it is determined in the third determination step that the exposure time is equal to or greater than the second threshold. In the fourth determination step, when it is determined in the third determination step that the detection sensitivity is less than the second threshold, it is determined whether the light amount is equal to or more than a third threshold (TH3). The first light quantity control step reduces the light quantity when it is determined in the fourth determination step that the light quantity is equal to or greater than the third threshold.

  According to such a configuration, when the brightness of the pattern image is high, first, the detection sensitivity is lowered and then the exposure time is shortened to reduce the light amount. Therefore, the influence on the measurement environment is reduced, It is possible to minimize the drop in measurement accuracy with respect to the optometry movement.

  Further, in the control method of the ophthalmologic apparatus according to the embodiment, the ophthalmologic apparatus includes a rotary prism (67) disposed in the light path of the pattern light, and the second threshold is equal to or more than the lower limit time defined by the rotational speed of the rotary prism. It may be.

  According to such a configuration, it is possible to suppress the decrease in measurement accuracy while obtaining the effect of averaging the light amount distribution by the rotary prism.

  In the control method of the ophthalmologic apparatus according to the embodiment, at least one of the first measurement condition determination step and the second measurement condition determination step includes a fifth determination step (step S33) and a sixth determination step (step S52). , Second light amount control step (step S53), seventh determination step (step S54), second exposure time control step (step S55), eighth determination step (step S56), and second detection sensitivity control step And (Step S57) may be included. The fifth determination step determines whether the luminance of the pattern image is low. The sixth determination step determines whether the light amount is equal to or less than a fourth threshold (TH4) when it is determined in the fifth determination step that the luminance is low. The second light quantity control step increases the light quantity when it is determined in the sixth determination step that the light quantity is equal to or less than the fourth threshold. The seventh determination step determines whether the exposure time is equal to or less than a fifth threshold (TH5) when it is determined in the sixth determination that the light amount exceeds the fourth threshold. The second exposure time control step lengthens the exposure time when it is determined in the seventh determination step that the exposure time is equal to or less than the fifth threshold. The eighth determination step determines whether the detection sensitivity is equal to or less than a sixth threshold (TH6) when the exposure time is determined to exceed the fifth threshold in the seventh determination step. The second detection sensitivity control step increases the detection sensitivity when it is determined in the eighth determination step that the detection sensitivity is equal to or less than a sixth threshold.

  According to such a configuration, when the luminance of the pattern image is low, first, the exposure time is increased after the light amount is increased, and the detection sensitivity is increased. Therefore, the noise component is increased by increasing the detection sensitivity. It is possible to minimize the decrease in measurement accuracy with respect to the movement of the eye while suppressing.

  Further, in the control method of the ophthalmologic apparatus according to the embodiment, the light source is disposed so as to be approximately optically conjugate with the fundus (Ef) of the eye to be examined, and the ophthalmologic apparatus is substantially conjugate to the pupil of the eye to be examined optically A diaphragm (ring diaphragm 65) disposed at a proper position (Q) and formed with a light transmitting portion for transmitting light from the light source, and a deflection member (cone prism 63, A ring lens 69) may be included, and the light transmitted through the light transmitting portion may be projected onto the eye as pattern light.

  According to such a configuration, it is possible to project thin pattern light (with narrow inner diameter and outer width) on the fundus, so that the pattern obtained by projecting high-brightness pattern light can be obtained. It becomes possible to improve the analysis accuracy of the image. As a result, it is possible to measure the eye refractive power with higher accuracy than in the prior art by performing a pattern image with high luminance and performing a plurality of temporary measurements.

<Other Modifications>
The embodiment shown above is only an example for implementing this invention. A person who intends to practice the present invention can make any modification, omission, addition, and the like within the scope of the present invention.

  In the above-mentioned embodiment, although the case where a transmission type liquid crystal panel was used as target chart 43 was explained, the composition of the ophthalmologic apparatus concerning an embodiment is not limited to this. The target chart 43 may be an optical chart.

  Instead of changing the exposure time of the imaging device 59 in the above-described embodiment, the number of superimposed images of images obtained by the imaging device 59 may be changed. In this case, the arithmetic processing unit 120 (analyzing unit 121) can perform the superposition processing of the images obtained by the imaging device 59 with the number of overlapping sheets specified by the main control unit 111.

DESCRIPTION OF SYMBOLS 1 Z alignment system 2 XY alignment system 3 Kerat measurement system 4 Target projection system 5 Front eye observation system 6, 6 a Ref measurement projection system 7 Reflex measurement light reception system 9 Processing unit 63 Conical prism 64 Field lens 65 Ring diaphragm 69 Ring lens 110 control unit 111 main control unit 121 analysis unit 1000, 1000a ophthalmologic apparatus

Claims (14)

An optical system which projects pattern light based on light from a light source onto an eye to be examined, and receives the return light of the pattern light from the eye through a focusing lens whose focal position can be changed;
An analysis unit that calculates an eye refractive power value of the subject's eye based on the pattern image obtained by the image sensor;
A first measurement including at least one of the light amount of the light source, the exposure time of the imaging device, the detection sensitivity of the imaging device, and the control content of the focusing lens based on the first pattern image obtained by the imaging device A second condition including the at least one of the light intensity, the exposure time, the detection sensitivity, and the control content based on a second pattern image obtained by the imaging device under the first measurement condition; The measurement condition is determined, and the eye refracting power value is calculated by the analysis unit based on the third pattern image obtained by the imaging device in a state in which the subject's eye is clouded under the second measurement condition. A control unit,
Ophthalmic device including. The light source is disposed so as to be approximately optically conjugate with the fundus of the subject's eye,
The optical system is
A diaphragm disposed at a position substantially optically conjugate with the pupil of the eye to be examined and formed with a light transmitting portion transmitting light from the light source;
A deflecting member that deflects light from the light source and guides the light to the light transmitting portion;
Including
The ophthalmologic apparatus according to claim 1, wherein the light transmitted through the light transmitting unit is projected as the pattern light onto the eye to be examined. The control unit executes the first luminance reduction control when the luminance of the first pattern image is high, and executes the first luminance increase control when the luminance of the first pattern image is low, and the luminance of the second pattern image is generated. The ophthalmologic apparatus according to claim 1 or 2, wherein the second brightness reduction control is executed when H is high, and the second brightness increase control is executed when the brightness of the second pattern image is low. At least one of the first brightness reduction control and the second brightness reduction control performs the exposure time after the first detection sensitivity control to reduce the brightness of the pattern image by lowering the detection sensitivity based on the brightness of the pattern image. 4. The ophthalmologic apparatus according to claim 3, wherein the first exposure time control to lower the brightness of the pattern image is performed by shortening the length. At least one of the first luminance reduction control and the second luminance reduction control performs first light amount control for reducing the luminance of the pattern image by reducing the light amount after the first exposure time control. The ophthalmologic apparatus according to claim 4. The optical system includes a rotary prism disposed in an optical path of the pattern light,
The ophthalmologic apparatus according to claim 4 or 5, wherein the first exposure time control shortens the exposure time to be equal to or more than a lower limit time defined by a rotational speed of the rotary prism. At least one of the first brightness increase control and the second brightness increase control increases the light intensity to increase the brightness of the pattern image, and then extends the exposure time after the second light intensity control to increase the brightness of the pattern image. The ophthalmologic apparatus according to any one of claims 3 to 6, wherein a second exposure time control is performed. At least one of the first brightness increase control and the second brightness increase control performs second detection sensitivity control to increase the brightness of the pattern image by increasing the detection sensitivity after the second exposure time control. The ophthalmologic apparatus according to claim 7. The ophthalmologic apparatus according to any one of claims 1 to 8, wherein the pattern light is ring-shaped light. The pattern light based on the light from the light source is projected onto the subject's eye, and the return light from the subject's eye of the pattern light is received by the imaging device through the focusing lens whose focal position can be changed. A control method of an ophthalmologic apparatus for measuring refractive power, comprising:
A first light source includes at least one of a light amount of the light source, an exposure time of the image pickup device, a detection sensitivity of the image pickup device, and control contents of the focusing lens based on the first pattern image obtained by the image pickup device. A first measurement condition determination step of determining a measurement condition;
A second measurement condition including at least one of the light amount, the exposure time, the detection sensitivity, and the control content is determined based on a second pattern image obtained by the imaging device under the first measurement condition. A second measurement condition determining step
A fog control step of causing the subject eye to fog under the second measurement condition;
A measuring step of measuring the refractive power in a state in which the subject's eye is seen fogged in the fog control step;
Method of controlling an ophthalmologic apparatus including: At least one of the first measurement condition determination step and the second measurement condition determination step is
A first determination step of determining whether the brightness of the pattern image is high;
A second determination step of determining whether the detection sensitivity is equal to or greater than a first threshold when it is determined that the luminance is high in the first determination step;
A first detection sensitivity control step of decreasing the detection sensitivity when it is determined in the second determination step that the detection sensitivity is equal to or higher than the first threshold;
A third determination step of determining whether the exposure time is greater than or equal to a second threshold when the detection sensitivity is determined to be less than the first threshold in the second determination step;
A first exposure time control step of shortening the exposure time when it is determined in the third determination step that the exposure time is the second threshold or more;
A fourth determination step of determining whether the light amount is equal to or more than a third threshold when the detection sensitivity is determined to be less than the second threshold in the third determination step;
A first light amount control step of decreasing the light amount when it is determined in the fourth determination step that the light amount is equal to or greater than the third threshold;
The control method of an ophthalmologic apparatus according to claim 10, comprising: The ophthalmologic apparatus includes a rotary prism disposed in an optical path of the pattern light,
The control method of the ophthalmologic apparatus according to claim 11, wherein the second threshold is equal to or more than a lower limit time defined by a rotational speed of the rotary prism. At least one of the first measurement condition determination step and the second measurement condition determination step is
A fifth determination step of determining whether the brightness of the pattern image is low;
A sixth determination step of determining whether the light amount is equal to or less than a fourth threshold when the luminance is determined to be low in the fifth determination step;
A second light amount control step of increasing the light amount when it is determined in the sixth determination step that the light amount is equal to or less than the fourth threshold;
A seventh determination step of determining whether the exposure time is equal to or less than a fifth threshold when the light amount is determined to exceed the fourth threshold in the sixth determination step;
A second exposure time control step of lengthening the exposure time when it is determined in the seventh determination step that the exposure time is equal to or less than the fifth threshold;
An eighth determination step of determining whether the detection sensitivity is equal to or less than a sixth threshold when it is determined in the seventh determination step that the exposure time exceeds the fifth threshold;
A second detection sensitivity control step of increasing the detection sensitivity when it is determined in the eighth determination step that the detection sensitivity is equal to or less than the sixth threshold;
The control method of the ophthalmologic apparatus according to any one of claims 10 to 12, further comprising: The light source is disposed so as to be approximately optically conjugate with the fundus of the subject's eye,
The ophthalmologic apparatus
A diaphragm disposed at a position substantially optically conjugate with the pupil of the eye to be examined and formed with a light transmitting portion transmitting light from the light source;
A deflecting member that deflects light from the light source and guides the light to the light transmitting portion;
Including
The control method of the ophthalmologic apparatus according to any one of claims 10 to 13, wherein the light transmitted through the light transmitting portion is projected as the pattern light onto the eye to be examined.

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