JP2011120610A - Perimeter and slit lamp provided with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a perimeter for a slit lamp, inspecting (measuring) the visual field of an eye of a subject by a simple configuration, and to provide a slit lamp provided with it. <P>SOLUTION: The perimeter used by being attached to the slit lamp for observing the subject's eye includes: a visual target presentation unit for presenting a visual field inspection visual target and a fixation mark to the fundus of the subject's eye; an arm for connecting the visual target presentation unit to the base shaft of the slit lamp so as to be rotated in the horizontal direction; a sensor for detecting the rotation angle of the arm with respect to the base shaft; and a control part for controlling the presentation position of the fixation mark in the visual target presentation unit so as to fix the presentation position of the fixation mark to the subject's eye even when the visual target presentation unit is moved by the rotation of the arm on the basis of the detected result of the sensor. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a perimeter for a slit lamp and a slit lamp including the perimeter.

  In an ophthalmological examination, a microscope called a slit lamp is commonly used to observe an anterior eye portion such as a cornea of a subject's eye, a posterior eye portion such as a fundus, and the like. On the other hand, a perimeter is known as one of apparatuses for inspecting the visual function of a subject's eye, and in recent years, an inspection apparatus having both a slit lamp function and a perimeter function has been proposed (for example, Patent Document 1).

JP 2003-153861 A

  However, the apparatus of Patent Document 1 is a dedicated machine having a configuration different from that of a conventional slit lamp, and when used only as a slit lamp, the apparatus is expensive.

  In view of the above-described problems of the prior art, the present invention provides a perimeter for a slit lamp capable of examining (measuring) the visual field of a subject's eye with a simple configuration and a slit lamp including the same. To do.

In order to solve the above problems, the present invention is characterized by having the following configuration.
(1) A perimeter used by being attached to a slit lamp for observing a subject's eye includes a visual target presentation unit that presents a visual field inspection target and a fixation target on the fundus of the subject's eye, Based on the detection result of the sensor, the arm that connects the optotype presenting unit to the base shaft of the slit lamp so as to be rotatable in the horizontal direction, the rotation angle of the arm with respect to the base shaft, and the rotation of the arm A control unit that controls the fixation target presentation position in the visual target presentation unit so that the fixation target presentation position on the subject's eye is constant even when the visual target presentation unit is moved. It is characterized by.
(2) In the perimeter of (1), the target presentation unit includes a display for displaying a visual field inspection target and a fixation target on a display panel, and the control unit is based on a detection result of the sensor. The display position of the fixation target on the display panel is controlled.
(3) In the perimeter of (1) or (2), the optotype presenting unit includes an illumination optical system for illuminating the fundus of the subject's eye and an observation for observing the fundus of the subject's eye And an optical system.
(4) A perimeter of any one of (1) to (3) is provided.

  According to the present invention, the visual field of the subject's eye can be inspected with a simple configuration.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic external view of a slit lamp equipped with a perimeter unit in an embodiment of the present invention. FIG. 2 is a schematic configuration diagram of an optical system and a control system of a slit lamp equipped with a perimeter unit.

  The slit lamp 100 includes an illumination unit 60, a microscope unit (observation unit) 70, and a moving unit 80.

  The moving unit 80 includes a slide base 102 that can slide in the horizontal direction (front / rear / left / right direction) on the table 101, and an operating rod that is gripped and tilted by the examiner's hand to move the slide base 102. Joystick) 103 and a base shaft 104 extending substantially vertically upward from the slide 102. In addition, since the moving mechanism of the sliding base 102 including the operating rod 103 is known, the description is abbreviate | omitted.

  The base shaft 104 supports an arm 106 that supports the illumination unit 60 and an arm 107 that supports the microscope unit 70 so as to be rotatable in the horizontal direction about the axis A. Thereby, the illumination unit 60 and the microscope unit 70 can be individually rotated with respect to the base shaft 104.

  Although not shown, the slit lamp 100 includes a face support unit that supports the subject's face (head) so that the subject's eye E is positioned above the upper portion 104 a of the base shaft 104. The face support unit is fixed to the fixed portion 102 a of the table 101 or the slide table 102.

  The perimeter unit 50 used by being attached to the slit lamp 100 is connected to the slit lamp 100 by an arm 105. The arm 105 is supported by the base shaft 104 so as to be rotatable in the horizontal direction around the axis A. As a result, the perimeter unit 50 can rotate with respect to the base shaft 104.

  The perimeter unit 50 of the present embodiment is detachable from the slit lamp 100, and the arm 105 includes a fixed portion 105a that is attached and fixed to the base shaft 104, and a movable portion 105b that is rotatable with respect to the fixed portion 105a. And an arm part 105c coupled to the movable part 105b. Each of the base shaft 104, the fixed portion 105a, and the movable portion 105b is provided with a reference position for rotation of the arm 105.

  The arm 105 is provided with a sensor 55 that detects a rotation angle of a predetermined position (reference position) of the arm 105 (movable part 105b) with respect to a predetermined position (reference position) of the base shaft 104 (fixed part 105a). The sensor 55 of the present embodiment is a rotary potentiometer provided in the fixed part 105a and the movable part 105b. The sensor for detecting the rotation angle of the arm 105 with respect to the base shaft 104 may be a known sensor such as a photo interrupter provided in the fixed portion 105a and the movable portion 105b.

  The perimeter unit (target presentation unit) 50 includes an illumination optical system 10, an observation optical system 20, a target presentation optical system 30, a control unit 40, a memory 41, an operation unit 42, a monitor 45, and the like (FIG. 2 ( a)).

  Infrared light from the light source 11 passes through the condenser lens 12 and illuminates the ring slit 13. The infrared light that has passed through the ring slit 13 passes through the lens 14 and is reflected by the reflecting surface around the aperture of the perforated mirror 15. The infrared light reflected by the perforated mirror 15 passes through the objective lens 16, forms an image in the vicinity of the pupil of the subject eye E, and then diffuses to illuminate the fundus of the subject eye E. With such a configuration, the illumination optical system 10 is established (see FIG. 2A).

  The infrared light reflected by the fundus of the subject's eye E passes through the objective lens 16 and passes through the aperture of the perforated mirror 15. The infrared light that has passed through the perforated mirror 15 passes through the lenses 21, 22, and 23, and is reflected by the dichroic mirror 24 that has the property of reflecting infrared light and transmitting visible light. The infrared light reflected by the dichroic mirror 24 passes through the lens 25 and forms an image on the light receiving surface of the observation camera 26 having sensitivity in the infrared region. With such a configuration, the observation optical system 20 is established (see FIG. 2A).

  The aperture of the perforated mirror 15 is at a position substantially conjugate with the pupil of the subject's eye E, and has a role of an imaging aperture. The lens 22 is a focusing lens that can move in the optical axis direction, and has a substantially conjugate relationship between the fundus of the subject eye E and the light receiving surface of the camera 26.

  A liquid crystal display (hereinafter referred to as LCD) 31 displays a visual field inspection target and a fixation target on its display panel. The fixation target is formed at the center of the LCD 31 (on the optical axis L of the target presentation optical system 30). The target formed by the LCD 31 passes through the reduction lens 32, the lens 33, and the dichroic mirror 24, passes through the lenses 23, 22 and 21, passes through the perforated mirror 15, passes through the objective lens 16, and passes through. It is projected onto the fundus of examiner's eye E. With such a configuration, the optotype presenting optical system 30 is established (see FIG. 2A).

  The visual target may not be presented by an electric display, but may be presented by a display board or the like in which a plurality of light emitting elements are arranged in an array.

  The control unit 40 is imaged by the light source 11, the camera 26, the LCD 31, a memory 41 in which a target parameter, an inspection program, and the like are stored, an operation unit 42 for changing a target parameter, and the like. A monitor 45, a sensor 55, and the like for displaying an observed fundus observation image are connected.

  The operation unit 42 changes parameters such as a small joystick 42a tilted by the examiner's finger to change the presentation position of the visual field inspection target, and the luminance, size, color, and the like of the visual field inspection target. A rotation knob 42b for switching, a button 42c for switching a parameter adjusted by the knob 42b, a trigger button 42d for presenting a visual field inspection target, and the like. The operation unit 42 is provided on the arm 105, the operation rod 42a is located on the examiner side, and the knob 42b and the buttons 42c and 42d are located on the subject side. Thus, the examiner who holds the arm 105 (operation unit 42) with his / her hand can operate the operation rod 42a with his / her thumb and can operate the knob 42b and the buttons 42c and 42d with the other four fingers.

  In the illumination unit 60, the white visible light from the light source 61 passes through the condenser lens 62 and illuminates the variable aperture 63 and the variable slit 64. The visible light that has passed through the aperture 63 and the slit 64 passes through the projection lens 65, is reflected by the prism mirror 66, and is projected onto the subject's eye E. With such a configuration, the illumination optical system 60a is established (see FIG. 2B).

  In the microscope unit 70, the visible light reflected by the subject eye E passes through the objective lens 71, the variable magnification optical system 72, and the imaging lens 73 and is reflected by the erecting prism 74. The visible light reflected by the prism 74 passes through the field stop 75, passes through the eyepiece lens 76, and enters the examiner's eye F. With such a configuration, the observation optical system 70a is established (see FIG. 2B).

  Next, the operation of the visual field inspection in the perimeter unit 50 attached to the slit lamp 100 will be described.

  When the examiner observes the anterior eye portion, the posterior eye portion, and the like of the subject's eye E, the examiner holds the illumination unit 60 and the microscope unit 70 substantially in front of the subject's face supported by the face support unit. Come (place). On the other hand, when inspecting the visual field of the subject's eye E, the illumination unit 60 and the microscope unit 70 are moved to the side, and the perimeter unit 50 is held substantially in front of the subject's face supported by the face support unit. Come (place).

  When performing the visual field inspection, the examiner aligns the perimeter unit 50 so that the fundus image of the subject eye E is captured by the camera 26 and displayed on the monitor 45, and the subject eye E has the LCD 31. Gaze at the fixation target presented by.

  The examiner operates the operation unit 42 to present the visual field inspection target and inspects the visual field of the subject's eye E. In the visual field inspection, the examiner may intentionally shake the perimeter unit 50 (arm 105) from side to side. Further, the perimeter unit 50 (arm 105) may swing left and right unconsciously.

  An example will be described in which the perimeter unit 50 (the target-presenting optical system 30 including the LCD 31) moves in the direction of arrow B and the optical axis L moves from the reference axis La to Lb. The control unit 40 obtains the rotation angle θ of the arm 105 based on the detection signal of the sensor 55, that is, the rotation angle θ of the perimeter unit 50 (target presentation optical system 30). The rotation center at this time is the pupil center of the subject's eye E. Then, the control unit 40 determines the movement distance M of the center of the LCD 31 based on the optical axis length (distance between the LCD 31 and the pupil center of the subject eye E) D of the perimeter unit 50 (target presentation optical system 30). It is calculated using the following relational expression.

M = D · sinθ
Based on the calculated movement distance M, the control unit 40 changes the display position of the fixation target to a position away from the center position of the LCD 31 by the movement distance M in the direction opposite to the arrow B. Thereby, the display position of the fixation target to the subject eye E by the LCD 31 is maintained on the reference axis La. That is, the control unit 40 displays the fixation target by the LCD 31 so that the position of the fixation target presented to the subject eye E is constant even when the perimeter unit 50 (target presentation optical system 30) is moved. Controlling the Presenting Position With the configuration described above, the visual field of the subject eye E can be suitably examined by freely shaking the perimeter unit 50 that can be retrofitted to the slit lamp 100 to the left and right. Thereby, even if the range of the visual field inspection of the perimeter unit 50 (the range in which the visual field inspection target can be presented) is small, the visual field can be inspected while guiding fixation of the eye E of the subject. For example, even if the range of the visual field inspection of the perimeter unit 50 is about the macula, the visual field of the nipple can be inspected by moving the perimeter unit 50 after inspecting the visual field of the macular region.

  In particular, in the case of the perimeter unit 50 of the present embodiment, since it is used by being attached to the slit lamp 100, the subject's eye E can be seen from the target presentation position as compared with the perimeter dedicated machine. Distance (inspection distance) tends to be long, and the range of visual field inspection (the range in which visual field inspection targets can be presented) tends to be narrow. Therefore, the examiner can freely move the perimeter unit 50, and the presenting position of the fixation target is corrected (changed) according to the movement (not only intentional movement but also unconscious movement). Therefore, the visual field inspection can be performed smoothly. On the other hand, a method to lock the movement (rotation) of the perimeter unit is conceivable in order to suppress the shaking (hand shake) of the perimeter unit. However, as described above, it is desired to move the perimeter unit freely and perform visual field inspection. In this case, it is troublesome to lock the perimeter unit every time it is moved. Therefore, the visual field inspection can be performed more smoothly by adopting a configuration in which the fixation position of the fixation target is corrected (changed) in accordance with the movement of the perimeter unit.

  In the above description, the display position of the fixation target on the LCD 31 which is the target presentation unit is changed. However, the present invention is not limited to this, and the display position of the fixation target by the target presentation unit is the perimeter. Any structure that is constant regardless of the movement of the unit may be used. FIG. 4 is a diagram illustrating a modification example of the optotype presenting unit. The optotype presenting unit 82 includes a liquid crystal display (LCD) 83 that presents a visual field inspection target, a half mirror 84, a fixation lamp 85 that serves as a fixation target, a drive unit 86 that moves the fixation lamp 85 in the direction of arrow C, Etc. The control unit 40 controls the drive unit 86 based on the detection result of the sensor 55 to move the fixation lamp 85. Thereby, the position where the fixation target is presented to the eye E can be corrected (changed).

It is a general | schematic external appearance perspective view of the slit lamp which attached the perimeter unit in embodiment of this invention. It is a schematic block diagram of the optical system and control system of the slit lamp which attached the perimeter unit. It is a figure which shows the relationship between the rotation angle of a perimeter unit, and the display position of a fixation target. It is a figure which shows the example of a change of a target presentation part.

31 Liquid Crystal Display 40 Control Unit 42 Operation Unit 55 Sensor 50 Perimeter Unit 60 Illumination Unit 70 Microscope Unit 100 Slit Lamp

Claims (4)

The perimeter used attached to the slit lamp to observe the subject's eyes is
An optotype presenting unit that presents a visual field inspection target and a fixation target on the fundus of the subject's eye;
An arm for connecting the target presentation unit to the base shaft of the slit lamp so as to be rotatable in a horizontal direction;
A sensor for detecting a rotation angle of the arm with respect to the base shaft;
Based on the detection result of the sensor, even if the target presentation unit is moved by the rotation of the arm, the fixation of the target presentation unit is fixed so that the position of the fixation target presented to the subject's eye is constant. A control unit for controlling the presentation position of the mark;
Comprising a perimeter. The perimeter of claim 1,
The optotype presenting unit includes a display that displays a visual field inspection target and a fixation target on a display panel;
The control unit controls a display position of the fixation target on the display panel based on a detection result of the sensor;
This is a perimeter. The perimeter according to claim 1 or 2,
The optotype presenting unit includes an illumination optical system for illuminating the fundus of the subject's eye, and an observation optical system for observing the fundus of the subject's eye,
This is a perimeter. Comprising the perimeter of any of claims 1-3.
A slit lamp characterized by that.

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