JP2004033377A - Opthalmologic examination apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a sure opthalmologic examination to be conducted by preventing a subject from losing sight of a fixation target. <P>SOLUTION: A fixation target display means for guiding a line of fixation of an eye to be examined detects a moving state of an external fixation light 61 and a change in a line-of-sight guiding direction via the selecting state of a plurality of fixation targets 31 in a constitution having the external fixation light 61 and an internal fixation light having a plurality of the fixation targets 31. When the change in the direction of guiding the line of the sight is detected, display states of the external fixation light and the internal fixation light are switched from normal display states to enhanced states. The enhanced states of the external fixation light and the internal fixation light are automatically reset to the normal display state after a predetermined time is elapsed so as not to impart an influence to constricted pupil state of the eye to be examined. The scope of the enhanced state, that is, conditions of amounts of light, flashing or the like of the external and internal fixation lights can be set as desired. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an ophthalmologic examination apparatus having fixation target display means for guiding a line of sight of an eye to be examined.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in an ophthalmologic examination apparatus such as a fundus camera, a method of taking an image of a subject with a single bright spot (fixation target) in order to suppress eye movement of an eye to be examined and stabilize an imaging range has been known. Widely known.
[0003]
In order to form a fixation target, a configuration in which an external fixation lamp is mainly provided outside the main optical system of the ophthalmologic examination apparatus and a configuration in which an internal fixation lamp is provided inside the main optical system are known.
[0004]
Since the range of the fundus that can be photographed is determined by the position of the fixation target, the examiner moves the external fixation lamp or switches the internal fixation lamp to be turned on to obtain the range that he or she wants to photograph. Perform gaze guidance.
[0005]
[Problems to be solved by the invention]
In the conventional ophthalmic examination apparatus, when the external fixation light is moved or the internal fixation light is switched, the subject does not lose sight of the fixation light (fixation target) and the examination is interrupted. Often happens.
[0006]
In order to prevent the subject from losing sight of the fixation lamp, it is conceivable to increase the lighting brightness of the fixation lamp or make the fixation lamp stand out by blinking the fixation lamp. However, such a method may cause miosis of the eye to be examined, which may hinder imaging.
[0007]
An object of the present invention is to solve the above-described problems, to prevent a subject from losing sight of a fixation target, and to perform a reliable ophthalmic examination.
[0008]
[Means for Solving the Problems]
According to an embodiment of the present invention, there is provided an ophthalmologic examination apparatus including a fixation target display unit that guides a line of sight of an eye to be examined, a detection unit configured to detect a change in a gaze guidance direction by the fixation target display unit. And a control unit that switches the fixation target display state of the fixation target display unit from a steady display state to a highlighted display state when a change in the gaze guidance direction is detected by the detection unit.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0010]
FIG. 1 shows the configuration of a fundus camera employing the present invention.
[0011]
The optical system shown in the lower part of FIG. 1 is an illumination optical system. Illumination light from the lamp 1 passes through a condenser lens 2, a strobe light source 3 for photographing, and a condenser lens 4, and is reflected by a total reflection mirror 5, followed by a ring slit 6, a relay lens 7, a half mirror 8, and a relay lens. After that, the light enters the mirror 10 of the main optical system. The mirror 10 is a perforated total reflection mirror having a hole in the center. The illumination light is reflected by the mirror 10, passes through the objective lens 11, and is incident on the fundus Er from the pupil Ep of the eye E to be examined.
[0012]
The reflected light from the fundus Er is received again from the pupil Ep via the objective lens 11, passes through the imaging lens 12 and the focusing lens 13 via the hole in the mirror 10, and enters the return mirror 14. The light incident on the return mirror 14 is reflected by the mirror 15 during observation, and is observed by the examiner S via the field lens 16 and the eyepiece 17. On the other hand, when photographing the fundus image on the film 18, the return mirror 14 is removed from the optical path, the strobe light 3 as the photographing light source emits light, and the fundus image is photographed on the film 18.
[0013]
The fundus camera of FIG. 1 is provided with a CPU 20 for controlling the operation of the entire apparatus. The CPU 20 is provided on an operation panel and receives a signal from a shutter button 21 to move the return mirror 14 out of the optical path. . Further, a signal from a focus control knob 22 provided on the operation panel is input to the CPU 20, and the focus lens 13 is adjusted thereby to perform focus control. Similarly, the CPU 20 adjusts the light amount of the lamp 1 by receiving a signal from the observation light amount volume 23 provided on the operation panel.
[0014]
The fundus camera of FIG. 1 is provided with an external fixation lamp and an internal fixation lamp as fixation target display means.
[0015]
The external fixation lamp 61 is composed of a light source such as an LED, and is supported by an apparatus main body via an arm 62. The lighting state of the external fixation lamp 61 (and an internal fixation lamp described later) such as a lighting state, a light amount, and a blinking state is controlled by the CPU 20 via the lighting control circuit 52. The arm 62 is provided with a plurality of joints 63, and the examiner adjusts the arm 62 to guide the direction of the line of sight of the eye E to be examined.
[0016]
As will be described later, in the present embodiment, control is performed to change the lighting state of the fixation lamp when the gaze guidance direction of the external fixation lamp 61 changes. In the case of the external fixation lamp 61, since the gaze guidance direction is controlled by adjusting the arm 62 as described above, sensors 64, 64,... Are provided at the joints 63, 63,. ing. The sensor 64 includes an optical sensor, a magnetic sensor, and the like, and detects the movement of the joint 63. The output of the sensor 63 is input to the CPU 20. The change (movement) of the gaze guidance direction of the external fixation lamp 61 is performed by detecting the movement of the joint 63 (that is, the moving state or the position of the external fixation lamp 61) or by, for example, setting an acceleration sensor or the like to the external fixation lamp. It can also be detected by providing it at the tip of the viewing lamp 61 or the like.
[0017]
In the present embodiment, the arm 62 is manually operated by the examiner directly, but of course, the CPU 20 described later may be controlled via a motor drive mechanism or the like. In such a configuration, the movement of the arm 62 (change in the fixation direction) can be detected from the driving data or the driving state data of the arm 62 without using the sensor 63.
[0018]
On the other hand, the internal fixation lamp is arranged in the illumination optical system in the present embodiment. The internal fixation lamp is composed of a plurality of fixation targets 31 made of an LED, a liquid crystal, or the like. The gaze guidance direction is determined depending on which one of the fixation targets 31 arranged at different positions is turned on. The image of the fixation target 31 is introduced into the illumination optical system via the lens 32 and the half mirror 8, and guides the line of sight of the eye E to be examined. The lighting mode of each fixation target 31 (and the above-mentioned external fixation lamp) such as lighting / extinguishing, light amount, and blinking state is controlled by the CPU 20 via the lighting control circuit 52.
[0019]
The examiner manually determines which fixation target of the internal fixation lamp is to be turned on in order to determine the gaze guidance direction. In addition, in the case of the internal fixation lamp of the present embodiment, an examination (photographing) is performed. Which fixation target of the internal fixation lamp is to be turned on is automatically determined according to a mode (such as an auto mode described later).
[0020]
Which fixation target 31 of the internal fixation lamp is turned on is controlled by switches (30a, 30b, 30c ...) of the switch panel 30. The fixation targets 31 are arranged in an array corresponding to each switch of the switch panel 30. When the switches are operated, the fixation targets arranged corresponding to the positions of the switches are turned on.
[0021]
The fixation target 31 is for the right eye (located to the right of the vertical center line in the drawing) and for the left eye (to the left of the center line) for nipple imaging, nipple and macula imaging, and other imaging. The fixation target for nipple imaging is a switch 30a indicated by a white circle, the fixation target for nipple and macula imaging is a switch 30b indicated by a black circle, and other parts are indicated. Each of the fixation targets is turned on by operating each of the switches 30c indicated by the crosses for photographing.
[0022]
When the fixation target is turned on, the CPU 20 inputs a switch signal from the switch panel 30 and determines the fixation target 31 to be turned on. Further, the amount of light emitted from the strobe 3 can be controlled by the selected fixation target 31. For example, when the switch 30a is operated and the fixation target for nipple photography is lit correspondingly, the amount of strobe light is weakened, and the switch 30b is operated to illuminate the fixation target for nipple and macula photography. When the fixation target for photographing the other part of the fundus is turned on by operating the switch 30c, control is performed so that the amount of strobe light becomes strong.
[0023]
The switch panel 30 is provided with a switch for selecting whether to use an external fixation light or an internal fixation light. In the case of the present embodiment, this switch is an external fixation light switch 57. When the external fixation light switch 57 is enabled, the external fixation light 61 is turned on.
[0024]
The switch panel 30 is provided with an auto mode switch 56. The auto mode designated by the auto mode switch 56 is for automatically selecting the fixation target 31 of the internal fixation lamp. When a desired photographing center part is designated on the observation screen 54, the internal fixation lamp suitable for it is set. Is selected.
[0025]
As a configuration for designating the imaging center region on the observation screen 54, for example, a CCD camera or the like for imaging an observation image is arranged in the main optical system, and the captured image is projected on a monitor (not shown) such as a CRT. Then, the examiner designates a desired photographing center portion in the observation image on the monitor using a mouse or the like (not shown), and the fixation of the internal fixation lamp is turned on based on the relative coordinates of the photographing center portion on the current observation image. The goal 31 can be determined. At this time, whether to select the fixation target 31 for the left eye or the fixation target 31 for the right eye is determined according to the output of the sensor 53 that detects the gantry position. The sensor 53 detects the position of the main body on the gantry. The sensor 53 can detect which of the left and right eyes to be inspected is currently being observed.
[0026]
The switch panel 30 can be configured not only by hardware but also by software of the CPU 20 on a GUI combining a mouse and a monitor display.
[0027]
In the present embodiment, when a fixation target is presented by an external fixation lamp or an internal fixation lamp, the lighting light amount is determined in advance by the CPU 20 and the lighting control circuit 52 such that miosis of the subject's eye does not occur. Is controlled to a given fixed default value (a default value at the time of shipment or a value determined by the examiner via a user interface (not shown)).
[0028]
The default lighting state of the external / internal fixation lamp (hereinafter, referred to as “steady display state” or simply “steady state”) is a period during which the external fixation lamp is stationary, and switching of the internal fixation lamp is performed. Will be continued during the period that is not done.
[0029]
On the other hand, when the movement of the external fixation light is detected by the sensor 64 or when the internal fixation light is switched, that is, when the fixation direction (gaze guidance direction) is changed, the subject Changes the lighting state of the external / internal fixation lamp to a state different from the steady state so as not to lose sight of the fixation target. Hereinafter, the lighting state of the external / internal fixation lamp different from the steady state is referred to as “highlighted state” or simply “highlighted” for convenience.
[0030]
This highlighted state can be created, for example, as follows.
[0031]
(1) Change the lighting light amount of the fixation lamp (usually increase the light amount).
[0032]
(2) Blink the fixation lamp. Alternatively, if the light is already blinking in the steady state, the blinking interval is shortened.
[0033]
Further, the highlighting state of the fixation lamp is when the movement of the external fixation lamp is detected by the sensor 64 and when the internal fixation lamp is switched, that is, when the fixation direction is changed, After a certain period of time, the display is returned to the steady display state so as not to affect the miotic state of the subject's eye. The continuous time of the highlighted display state after the change in the fixation direction is preferably, for example, about several seconds.
[0034]
Further, it is preferable that the details of the manner of highlighting the fixation target can be set by the fixation lamp lighting setting means 51. The fixation lamp lighting setting means 51 can be configured by a control program of the CPU 20 and user interface hardware (a mouse, a keyboard, a monitor, etc., and of course, a dedicated switch panel may be used).
[0035]
It is desirable that at least the following settings can be made by the fixation lamp lighting setting means 51.
[0036]
(1) Whether or not to highlight the fixation target when the fixation direction changes (2) Duration of highlighting (3) Whether to perform highlighting by changing the amount of light or blinking (4) Emphasis The amount of change in the amount of lighting at the time of display and the blinking period (5) Whether the setting of highlighting is applied to an external fixation lamp or an internal fixation lamp.
[0037]
FIG. 2 shows a program flow of the CPU 20 for controlling the user interface for setting the manner of highlighting the fixation target as described above.
[0038]
In step S1 of FIG. 2, it is determined which of the external fixation lamp and the internal fixation lamp is to be set to be highlighted according to the input state of the user interface hardware of the fixation lamp lighting setting means 51.
[0039]
In step S2, the duration of the highlighting is set according to the input state of the user interface hardware of the fixation lamp lighting setting means 51. This duration can be input by numerical input, a slide bar arranged in a dialog on the GUI screen, or the like.
[0040]
In step S3, it is set according to the input state of the user interface hardware of the fixation lamp lighting setting means 51 whether to perform the highlighting by changing the lighting light amount or by blinking. This setting can be made by a button or the like arranged in a dialog on the GUI screen.
[0041]
In accordance with the selection in step S3, in step S4 or S5, the amount of change in the amount of light or the blinking period for highlighting is set, respectively. The amount of change or the blinking period can be input by numerical input, a slide bar arranged in a dialog on the GUI screen, or the like.
[0042]
In step S6, it is determined whether to end the setting according to the input state of the user interface hardware of the fixation lamp lighting setting unit 51. If the setting is not completed, it is desirable that the above-described settings can be made.
[0043]
FIG. 2 shows the setting of highlighting in the form of a flowchart for the sake of convenience, and the setting of each step may be performed in any order. If a GUI screen is used for the fixation lamp lighting setting means 51, usually, most of these types of settings can be performed by operating buttons and slide bars or inputting text (numerical values) in a user's desired order.
[0044]
The control program of the CPU 20 for executing the procedure of FIG. 2 or other control is stored in a medium such as a ROM, and the supply path may be arbitrarily provided by an external storage medium. It may be supplied via a port.
[0045]
As described above, according to the present embodiment, when the fixation direction (gaze guidance direction) by the fixation target is changed, the fixation target is highlighted, so that the subject can fixate. There is an excellent effect that the goal can be reliably prevented from being lost.
[0046]
Further, according to the present embodiment, since the highlighting of the fixation target is stopped after a predetermined duration has elapsed, the ophthalmologic examination is reliably performed without affecting the miotic state of the eye to be examined. I can do it.
[0047]
Furthermore, according to the present embodiment, the change in the fixation direction (gaze guidance direction) due to the fixation target is determined by moving the external fixation light or switching the internal fixation light (for the nipple photographing of the switch panel 30 and the macular portion photographing). And automatic switching by an auto mode set by the auto mode switch 56), and automatically detected, and automatically highlights the fixation target (and returns to a steady display state). Is controlled, the examiner does not need to perform any troublesome operation during the examination.
[0048]
Also, as shown in FIG. 2, whether or not highlighting is performed when the fixation direction changes, or in the case where further highlighting is performed, if details of the mode can be set, the examination status, the subject, The fixation target suitable for the inspection environment can be highlighted.
[0049]
In addition, when the external fixation light is moved or the internal fixation light is switched, the subject may lose sight of the fixation target due to a small amount of movement of the line of sight or a small movement speed (acceleration). If the performance is low, control may be performed so as not to switch to the highlighted display state. For example, when the amount of movement of the external fixation light is equal to or less than a predetermined value (such as the amount of movement of the joint 63 by the sensor 63 is equal to or less than a predetermined value), the moving speed or acceleration of the external fixation light is equal to or less than a predetermined value (using an acceleration sensor or the like). In such a case, such a parameter can be easily detected.) In such a case, switching to the highlighted display state is omitted. In the case of an internal fixation lamp, the switching to the highlighted display state may be omitted when the distance of the fixation target to be turned on before and after the switching is not so large. Further, the conditions for omitting the switching to the highlighted state (the above-described moving amount, moving speed, moving acceleration, distance between the fixation targets of the internal fixation lamp, and the like) can be set by the user interface as shown in FIG. It can be.
[0050]
【The invention's effect】
As is apparent from the above description, according to the present invention, in an ophthalmic examination apparatus having fixation target display means for guiding the gaze of the eye to be inspected, detection in which a change in the gaze guidance direction by the fixation target display means is detected. Means and control means for switching the fixation target display state of the fixation target display means from the steady display state to the emphasized display state when a change in the gaze guidance direction is detected by the detection means. Therefore, there is an excellent effect that the subject can be prevented from losing sight of the fixation target and an ophthalmic examination can be reliably performed.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a configuration of an ophthalmologic examination apparatus employing the present invention.
FIG. 2 is a flowchart illustrating a control procedure of a fixation lamp lighting setting unit in FIG. 1;
[Explanation of symbols]
REFERENCE SIGNS LIST 1 lamp 2 condenser lens 3 strobe 4 condenser lens 5 total reflection mirror 6 ring slit 7 relay lens 8 half mirror 9 relay lens 10 mirror 11 objective lens 12 imaging lens 13 focusing lens 14 return mirror 15 mirror 16 field lens 17 eyepiece lens 18 film 20 CPU
Reference Signs List 21 Shutter button 30 Switch panel 31 Fixation target 51 Fixation lamp lighting setting means 52 Lighting control circuit 53 Sensor 54 Observation screen 56 Auto mode switch 57 External fixation lamp switch 61 External fixation lamp 62 Arm 63 Joint section 64 Sensor E Optometry

Claims (4)

In an ophthalmic examination apparatus having fixation target display means for guiding the line of sight of the eye to be examined,
Detecting means for detecting a change in the gaze guidance direction by the fixation target display means,
An ophthalmologic examination apparatus comprising: a control unit that switches a fixation target display state of the fixation target display unit from a steady display state to an emphasized display state when a change in a gaze guidance direction is detected by the detection unit. The ophthalmologic examination apparatus according to claim 1, wherein after the highlighting state, the fixation target display state of the fixation target display unit is automatically returned to the steady display state. The detection means may detect a change in the gaze guidance direction by the fixation target display means via a moving state of the fixation target display means or a selection state of the plurality of fixation target display means. The ophthalmologic examination apparatus according to claim 1, wherein: 2. The ophthalmologic examination apparatus according to claim 1, further comprising a setting unit configured to set an aspect of the highlighted display state as desired.

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