JP3974824B2 - Ophthalmic examination equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ophthalmic examination apparatus having fixation target display means for guiding the line of sight of an eye to be examined.
[0002]
[Prior art]
Conventionally, in an ophthalmologic examination apparatus such as a fundus camera, there has been a method of taking an image by gazing at a single bright spot (fixation target) on a subject in order to suppress eye movement of the subject's eye and stabilize the photographing range. 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 ophthalmic examination apparatus and a configuration in which an internal fixation lamp is provided inside the main optical system are known.
[0004]
Since the fundus range that can be photographed is determined according to the position of the fixation target, the examiner moves the external fixation lamp or switches the internal fixation lamp to be lit to obtain the range to be photographed. Gaze guidance is performed.
[0005]
[Problems to be solved by the invention]
In a conventional ophthalmic examination apparatus, when the external fixation lamp is moved or the internal fixation lamp is switched, the subject does not lose sight of the fixation lamp (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 that the fixation lamp is made conspicuous by increasing the lighting brightness of the fixation lamp or blinking it. However, according to such a technique, there is a possibility that the miosis of the eye to be examined will be caused and the photographing may be hindered.
[0007]
An object of the present invention is to solve the above problems, prevent a subject from losing sight of a fixation target, and perform a reliable ophthalmic examination.
[0008]
[Means for Solving the Problems]
In order to solve the above-described problems, according to the present invention, in an ophthalmologic examination apparatus having a fixation target display unit that guides the line of sight of a subject's eye, a detection unit that detects a change in the gaze guidance direction by the fixation target display unit When the change of the gaze guidance direction is detected by the detection means, the fixation target display state of the fixation target display means is switched from the steady display state to the highlighted display state, but is detected via the detection means. When the movement amount, movement speed, or acceleration of the fixation target display by the fixation target display means is equal to or less than a predetermined value , a configuration having control means that omits switching from the steady display state to the highlighted display state is adopted.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0010]
FIG. 1 shows the structure 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. The illumination light of the lamp 1 is reflected by a total reflection mirror 5 through a condenser lens 2, a strobe 3 as a photographing light source, and a condenser lens 4, followed by a ring slit 6, and further a relay lens 7, a half mirror 8, and a relay lens. 9 enters the mirror 10 of the main optical system. The mirror 10 is a perforated total reflection mirror having a hole in the center, and the illumination light is reflected by the mirror 10 and then enters the fundus Er through the objective lens 11 and through 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 through the objective lens 11, passes through the imaging lens 12 and the focusing lens 13 through the hole of the mirror 10, and enters the return mirror 14. The light incident on the return mirror 14 is reflected by the mirror 15 at the time of observation, and is observed by the examiner S through the field lens 16 by the eyepiece 17. On the other hand, when the fundus image is photographed on the film 18, the return mirror 14 is removed from the optical path, the strobe 3 that is the photographing light source emits light, and the fundus image is photographed on the film 18.
[0013]
The fundus camera shown in FIG. 1 is provided with a CPU 20 for controlling the operation of the entire apparatus. This CPU 20 is provided on an operation panel and receives a signal from a shutter button 21 to disengage the return mirror 14 from the optical path. . Further, the CPU 20 receives a signal from a focus control knob 22 provided on the operation panel, thereby adjusting the focusing lens 13 and performing focus control. Similarly, the CPU 20 receives a signal from the observation light amount volume 23 provided on the operation panel and adjusts the light amount of the lamp 1.
[0014]
The fundus camera in 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 on the 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 the lighting state, the amount of light, and the 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 by the external fixation lamp 61 changes. In the case of the external fixation lamp 61, in order to control the line-of-sight guidance direction by adjusting the arm 62 as described above, sensors 64, 64... Are provided in the joint portions 63, 63. ing. The sensor 64 is configured by an optical sensor, a magnetic sensor, or the like, and detects the movement of the joint portion 63. The output of the sensor 64 is input to the CPU 20. The change (movement) of the gaze guidance direction of the external fixation lamp 61 is not limited to detecting the movement of the joint portion 63 (that is, the movement state or position of the external fixation lamp 61). It can also be detected by providing it at the tip of the viewing lamp 61 or the like.
[0017]
In this embodiment, the arm 62 is directly operated manually by the examiner, 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 driving state data of the arm 62 without using the sensor 64 .
[0018]
On the other hand, the internal fixation lamp is disposed in the illumination optical system in the present embodiment. The internal fixation lamp is composed of a plurality of fixation targets 31 made of LED or liquid crystal. The line-of-sight guidance direction is determined depending on which of the fixation target 31 arranged at different positions is lit. 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 direction of the eye E. Lighting states of each fixation target 31 (and the above-mentioned external fixation lamp) such as lighting / extinction, light amount, and blinking state are 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 turned on in order to determine the gaze guidance direction, and in the case of the internal fixation lamp of the present embodiment, inspection (imaging) is performed. It is automatically determined which fixation target of the internal fixation lamp is turned on according to the mode (auto mode described later).
[0020]
Which fixation target 31 of the internal fixation lamp is lit is controlled by the switches (30a, 30b, 30c...) Of the switch panel 30. The fixation target 31 is arranged in an arrangement corresponding to each switch of the switch panel 30. When the switch is operated, the fixation target arranged corresponding to the position of each switch is turned on.
[0021]
The fixation target 31 is for the right eye (located on the right side of the vertical center line in the drawing) and the left eye (left side of the center line) for nipple photography, nipple and macular photography, and other photography, respectively. The fixation target for photographing the nipple is indicated by a white circle, the fixation target for photographing the nipple and the macula is indicated by a black circle, and the other part. Each of the fixation targets is turned on by operating each of the switches 30c indicated by the x marks.
[0022]
When the fixation target is turned on, the CPU 20 inputs a switch signal from the switch panel 30 and determines a fixation target 31 to be turned on. Further, the amount of light emitted by 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 shooting is correspondingly turned on, the amount of strobe light becomes weak, and when the fixation target for shooting the nipple and the macula is turned on by operating the switch 30b. The strobe light amount becomes an intermediate value, and when the fixation target for photographing another part of the fundus is turned on by operating the switch 30c, control is performed so that the strobe light amount becomes strong.
[0023]
The switch panel 30 is provided with a switch for selecting whether to use an external fixation lamp or an internal fixation lamp. In this embodiment, this switch is an external fixation lamp switch 57. When the external fixation lamp switch 57 is activated, the external fixation lamp 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 automatically selects the fixation target 31 of the internal fixation lamp. When a desired photographing center portion is designated on the observation screen 54, an internal fixation lamp suitable for the fixation is designated. The fixation target 31 is selected.
[0025]
As a configuration for designating the photographing center part on the observation screen 54, for example, a CCD camera or the like for photographing an observation image is arranged in the main optical system, and the photographed image is projected on a monitor such as a CRT (not shown). Then, using an unillustrated mouse or the like, let the examiner specify a desired imaging center part in the observation image on the monitor, and fix the internal fixation lamp that lights up from the relative coordinates of the imaging center part on the current observation image A target 31 can be determined. At this time, whether to select the fixation target 31 on the left eye side or the fixation target 31 on the right eye side is determined according to the output of the sensor 53 that detects the gantry position. The sensor 53 detects a position of the main body on the gantry, and the sensor 53 can detect which eye to be examined is currently observed.
[0026]
The switch panel 30 can be configured not only by hardware but also by software of the CPU 20 on a GUI that combines a mouse and a monitor display.
[0027]
In the present embodiment, when the fixation target is presented by the external fixation lamp or the internal fixation lamp, the amount of lighting is determined in advance by the CPU 20 and the lighting control circuit 52 so that the miosis of the eye to be examined does not occur. To a predetermined default value (a default value at the time of shipment or a value determined by an examiner via a user interface (not shown)).
[0028]
This default external / internal fixation lamp lighting state (hereinafter referred to as “steady display state” or simply “steady state”) is performed while the external fixation lamp is stationary and the internal fixation lamp is switched. It will continue in the period that is not.
[0029]
On the other hand, when the movement of the external fixation lamp is detected by the sensor 64 or when the internal fixation lamp is switched, that is, when the fixation direction (gaze guidance direction) is changed, the subject is examined. Therefore, the lighting state of the external / internal fixation lamp is changed to a state different from the steady state so as not to miss the fixation target. Hereinafter, the lighting state of the external / internal fixation lamp different from the steady state is referred to as “highlighted display state” or simply “highlighted display” for convenience.
[0030]
This highlighted state can be created as follows, for example.
[0031]
(1) Change the amount of light of the fixation lamp (usually increase the amount of light).
[0032]
(2) Make the fixation lamp blink. Alternatively, if it is already blinking in a steady state, the blinking interval is shortened.
[0033]
Furthermore, the fixation display state of the fixation lamp is from when the movement of the external fixation lamp is detected by the sensor 64 and when the internal fixation lamp is switched, that is, from when the fixation direction is changed. When a certain period of time has elapsed, the steady display state is restored so as not to affect the miosis state of the eye to be examined. The continuous time of the highlighted state after the change of the fixation direction is preferably set to about several seconds, for example.
[0034]
Further, the details of the fixation target highlight display mode may be set by the fixation lamp lighting setting unit 51. The fixation lamp lighting setting means 51 can be configured by a control program of the CPU 20 and user interface hardware (mouse, keyboard, monitor, etc., of course, a dedicated switch panel may be used).
[0035]
It is desirable that at least the following setting can be made by the fixation lamp lighting setting means 51.
[0036]
(1) Whether the fixation target is highlighted when the fixation direction is changed (2) Duration of the highlighting (3) Whether the highlighting is performed by changing the amount of lighting or by flashing (4) Emphasis Whether the amount of change in the amount of lighting during display and the blinking cycle (5) highlight setting are applied to the external fixation lamp or the internal fixation lamp.
[0037]
FIG. 2 shows a program flow of the CPU 20 that controls the user interface for setting the fixation target highlighting mode as described above.
[0038]
In step S1 of FIG. 2, it is determined whether to perform highlight setting for either the external fixation lamp or the internal fixation lamp 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 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 or a slide bar arranged in a dialog on the GUI screen.
[0040]
In step S3, it is set whether the highlighting is performed by changing the lighting light amount or by blinking according to the input state of the user interface hardware of the fixation lamp lighting setting means 51. This setting can be performed 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 lighting light quantity or the blinking cycle at the time of highlighting is set. The amount of change or the blinking cycle can be input by numerical input or a slide bar arranged in a dialog on the GUI screen.
[0042]
In step S6, it is determined whether or not to end the setting according to the input state of the user interface hardware of the fixation lamp lighting setting means 51. When the setting is not finished, it is desirable to be able to make the above settings.
[0043]
Note that FIG. 2 shows a mode of setting highlighting in the form of a flowchart for convenience only, and the setting of each step may be performed in an arbitrary order. If a GUI screen is used for the fixation lamp lighting setting means 51, usually this kind of setting can be performed by operating buttons and slide bars and inputting text (numerical values) in the order desired by the user.
[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, the supply path is arbitrary, and the control program may be supplied by an external storage medium or a network. You may supply via.
[0045]
As described above, according to the present embodiment, the fixation target is highlighted when the fixation direction (gaze guidance direction) by the fixation target is changed. There is an excellent effect that it is possible to surely prevent losing the goal.
[0046]
Further, according to the present embodiment, the fixation target highlighting is stopped after a predetermined duration, so that the ophthalmic examination can be performed without affecting the miosis state of the eye to be examined. Can be carried out.
[0047]
Further, according to the present embodiment, the change of the fixation direction (gaze guidance direction) depending on the fixation target is caused by the movement of the external fixation lamp or the switching of the internal fixation lamp (for nipple photography of the switch panel 30 and macular photography). (In addition to the automatic switching by the auto mode set by the auto mode switch 56 in addition to the switching by other switches), and the fixation target highlight display (and the return to the steady display state) automatically. Therefore, the examiner does not need to perform troublesome operations during the examination.
[0048]
Also, as shown in FIG. 2, if the highlighting is performed when the fixation direction is changed, or if further highlighting is performed, the details of the mode can be set, so that the examination status, the subject, It is possible to highlight a fixation target suitable for the inspection environment.
[0049]
In addition, when moving the external fixation lamp or switching the internal fixation lamp, the subject may lose sight of the fixation target, such as the amount of movement of the line of sight is not so large or the movement speed (acceleration) is low. If the performance is low, it can be considered not to switch to the highlighted state. For example, when the movement amount of the external fixation lamp is less than or equal to a predetermined value (the movement amount of the joint portion 63 by the sensor 64 is less than or equal to a predetermined value), the movement speed or acceleration of the external fixation lamp is equal to or less than a predetermined value (using an acceleration sensor or the like). If it is possible to detect such parameters easily, switching to the highlighted state is omitted. In the case of an internal fixation lamp, switching to the highlighted state may be omitted when the distance to the fixation target to be turned on before and after switching is not so far. Furthermore, the conditions for omitting switching to the highlighted state (the above-mentioned movement amount, movement speed, movement acceleration, distance between fixation targets of the internal fixation lamp, etc.) can also 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 a fixation target display means for guiding the line of sight of the eye to be detected, detection for detecting a change in the direction of gaze guidance by the fixation target display means When the change of the gaze guidance direction is detected by the means and the detection means, the fixation target display state of the fixation target display means is switched from the steady display state to the highlighted display state, but is detected via the detection means. When the movement amount, movement speed, or acceleration of the fixation target display by the fixation target display means is less than or equal to a predetermined value , a configuration having a control means that omits switching from the steady display state to the highlighted display state is adopted. Therefore, it is possible to prevent the subject from losing sight of the fixation target and to perform an ophthalmic examination without fail.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a configuration of an ophthalmic examination apparatus employing the present invention.
FIG. 2 is a flowchart showing a control procedure of a fixation lamp lighting setting unit in FIG. 1;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 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 Focus lens 14 Return mirror 15 Mirror 16 Field lens 17 Eyepiece 18 Film 20 CPU
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 part 64 Sensor E Subject Optometry

Claims (5)

In an ophthalmic examination apparatus having fixation target display means for guiding the line of sight of an eye to be examined,
Detecting means for detecting a change in gaze guidance direction by the fixation target display means;
When a change in the gaze guidance direction is detected by the detection means, the fixation target display state of the fixation target display means is switched from a steady display state to an emphasized display state, but the fixation target display state detected via the detection means is changed. An ophthalmic examination comprising control means for omitting switching from the steady display state to the highlighted display state when the movement amount, movement speed, or acceleration of the fixation target display by the visual target display means is not more than a predetermined value apparatus.   The ophthalmic examination apparatus according to claim 1, wherein the fixation target display state of the fixation target display unit is automatically returned to the steady display state after the highlight display state.   The detection means detects a change in the gaze guidance direction by the fixation target display means through a movement state of the fixation target display means or a selection state of a plurality of fixation target display means provided. The ophthalmic examination apparatus according to claim 1.   The ophthalmic examination apparatus according to claim 1, further comprising a setting unit that sets a mode of the highlighted state as desired. The ophthalmic examination apparatus according to claim 1, further comprising setting means for setting a condition for omitting switching from the steady display state to the highlighted display state.

Images