JPH01238822A - Ophthalmologic device - Google Patents

Abstract

PURPOSE:To observe an eye under test and a measuring terminal from the front side when measuring the eye axis length by rotating and moving the measuring terminal located at a position other than the optical axis of an optical system to the measurement position on the optical axis in contact with the eye under test. CONSTITUTION:Whether an objective lens 7 faces the right eye side of a person under test or the left eye side is judged by a microswitch 27 switched for the opening/closing state by a cam 28 nearly at the center section of the slide of a movable bed 2 in the right or left eye direction, a sliding rotary shaft 15 is rotated in the preset rotating direction according to the state, a probe 19 is inserted on the optical axis between the objective lens 7 and cornea under test in a circular orbit not to collide with the nose ridge of the person under test. A female screw 20 is then rotated to move the probe 19 near the eye under test E. When the probe 19 is brought into contact with the eye under test E, ultrasonic vibration waves are applied to the eye under test E, reflected waves from the required section in the eye are detected by the same probe 19. The detected signal is inputted to a control arithmetic unit 12, the eye axis length of the eye under test is calculated based on the time difference between reflected waves from individual reflection points of required sections in the eye.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ophthalmological apparatus having an optical system for observation and a contact measuring terminal.

[Prior art] This is a device in which a corneal refractor and an eye glaze length meter are housed in the same main body, and the measuring device main body is aligned at an appropriate position with respect to the cornea of the eye to be examined in the state of measuring corneal curvature, and the eye axis is aligned. A device has already been proposed in which the optical system for observing the eye to be examined is retracted when switching to the length measurement mode, so that the axial length can be measured immediately.

[Problems to be solved by the invention] However, in the conventional example, when measuring the ocular axial length, when trying to make the measurement terminal that comes into contact with the eye to be examined function, the optical system for observing the eye to be examined is connected to the optical axis of the eye to be examined. Because it retreats from the upper imaging optical path,
There was a drawback that could be further improved: the eye to be examined and the measurement terminal could no longer be observed from the front.

[Means for Solving the Problems] In order to solve the above-mentioned problems, an ophthalmological apparatus that measures the eye to be examined by bringing a measuring terminal into contact with the eye to be examined includes an objective lens for observing the anterior segment of the eye to be examined. means for rotating and moving an optical system and the measurement terminal located at an initial position other than on the optical axis of the optical system to a measurement position located on the optical axis of the optical system on the eye to be examined side from the objective lens; and a means for moving the measurement probe, which has been moved to the measurement position, toward the eye to be examined and bringing it into contact with the eye to be examined.

[Example code] 1 to 3 show embodiments of the invention.

FIG. 1 shows the overall configuration, in which a base 1, a movable base 2, and a main body 6 mounted thereon constitute a sliding base that can move within a certain range. The operator rotates the upper and lower rings 3 to
up and down. Furthermore, by tilting the operating stick 4 in an arbitrary direction, the movable base 2 is slid in the direction in which the operating stick 4 is tilted. By pressing the measurement switch 5, a command is given to measure corneal curvature or ocular axial length. Reference numeral 7 denotes an objective lens that forms an image of the vicinity of the subject's eye E on the television camera 9. The optotype light source 8 is a light emitting diode (4 pieces), which illuminates the vicinity of the eye E to be examined, and its corneal reflection image is a bright spot image for corneal curvature measurement as disclosed in JP-A-62-250536. Become. The image of the eye E to be examined by the television camera 9 is displayed on the television monitor 10, and the measurement results are displayed numerically. Reference numeral 12 denotes a control calculation unit that controls the electrical system and drive system, and calculates measured values. 13 is a printer for printing out the calculation results, and 14 is printing paper.

The sliding rotation shaft 15 is supported by the guide section 11, and has an arm section 18 extending in the radial direction at its end on the subject side, and a probe 19 is attached to the tip end of the arm section 18. Note that it is desirable that the arm portion 18 and the probe 19 be as small as possible and made of a transparent material in order to reduce obstruction of the optical path.The probe 19 emits ultrasonic waves for measuring the axial length of the eye to be examined. It also detects the reflected waves of the emitted ultrasound waves from the main parts of the eye to be examined.

A gear 16 is attached to a substantially central portion of the sliding rotation shaft 15 and meshes with a gear 23 connected to a motor 24.

In addition, a male screw portion 1 is provided at the end of the sliding rotation shaft 15 on the opposite side to the subject.
7 is formed, and a female screw 20 is screw-fitted thereto. The female thread 20 is restricted from moving back and forth, and has a gear portion on its outer periphery, which meshes with a gear 21 connected to a motor 22.

FIG. 2 shows a cross-sectional view of a sliding table consisting of a base l and a movable table 2 in a direction perpendicular to the plane of the paper in FIG. A microswitch 27 is attached to the base 1, which is switched between open and closed states by a cam 28 at approximately the center of the sliding movement of the movable base 2 in the left and right directions.

Next, a procedure for measuring the corneal curvature of the eye to be examined will be explained. A support 25 is installed on the base 1 and has a face fixing table 26 that can move up and down within a certain range, on which the subject P fixes his or her face. In order to correctly align the eye E of the patient P who is fixed on the face fixing table 26, the operation lever 4 can be tilted so that the image displayed on the TV monitor 10 is clear and in the correct position. The upper and lower fJilJI are performed by aligning the positions and rotating the upper and lower rings. In this case, cam 2
By checking the opening/closing state of the microswitch 27 by 8, the control calculation unit 12 recognizes whether the measured silver is on the right eye side or the left eye side. When the operator presses the measurement switch 5, the optotype light source 8 is turned on, and a bright spot image caused by the lighting of the optotype light source 8 is projected onto the corneal reflection image detected by the television camera 9. By calculating the interval between the bright spot images in the control calculation unit 12, the corneal curvature and the degree of astigmatism can be calculated.

The resulting value can be displayed on the television monitor 10 by being superimposed with the image of the eye E to be examined. Further, the printer 13 can also print on the print paper 14 .

When the above corneal curvature measurement is completed, the operator presses the measurement switch 5 or a switch (not shown) again, or the axial length measurement operation is automatically started after the completion of the measurement.

Next, the operation of the apparatus when measuring the axial length will be explained.

The initial position of the probe 19 in the direction perpendicular to the direction connecting the right and left eyes of the subject (in this embodiment, the upper side, but may be the lower side) when the ocular axis length 7P is determined. Whether the objective lens 7 is facing the right eye side or the left eye side of the subject is determined by the opening/closing state of the microswitch 27, and depending on the state, the sliding rotation shaft 15 is rotated in a predetermined rotation direction. The probe 19 is rotated and inserted on the optical axis between the objective lens 7 and the cornea of the eye to be examined so as to prevent the probe 19 from hitting the nasal ridge of the skin examiner. Here, the predetermined direction is the ear side on the same side as the eye to be measured, that is, the right ear side when measuring the right eye.
'llll 11111 (clockwise as seen from the subject), and for left eye measurements, insert the probe 19 through the left ear side (counterclockwise as seen from the subject), tracing an arcuate trajectory. be done.

Subsequently, the motor 22 rotates to rotate the female thread 20,
The probe 19 on the optical axis is brought closer to the eye E by sending the male threaded portion 17 threaded thereto toward the eye to be examined. Since ultrasonic vibration waves are constantly being emitted from the probe 19, at the same time as the probe 19 and the eye E come into contact, the vibration waves are transmitted to the eye opening 1 within the eye E, and reflected waves from the main parts of the eye. is detected by the same probe I9.

The detected signal is i, 17θn 1 (manual force is applied to the nose 12, and the eye length of the subject's eye is calculated from the difference in the brightness of the reflected waves from each reflection wave in the main part of the eye.

The calculated axial length measurement result may be displayed on the television monitor 10 or output to the printer 13, similarly to the corneal curvature measurement result.

In this embodiment, since the motor 24 is required to operate accurately, it is preferable to use a step motor. Also, in this embodiment, the probe 19? Since contact with the skin eye can be detected by the appearance of a corneal surface reflection image, the rotation of the motor 22 is stopped based on this detection signal, but the rotation of the motor 22 is stopped by other known means.
It is also possible to do so.

When the axial length measurement is completed according to the above procedure, the motor 22.
24 is reversely rotated according to control conditions opposite to those at the start of measurement, thereby returning to the initial state of measurement.

In this embodiment, the probe 19 is located closer to the eye to be examined than the objective lens in the initial state of measurement, but when measuring corneal curvature, it is housed inside the main body at a point farther from the objective lens with respect to the eye to be examined, and when measuring the axial length, it is It goes without saying that it is also possible to proceed straight in the direction of the eye to be examined, reach the eye to be examined than the objective lens, rotate and insert it on the optical axis, and operate as in the following embodiments.

Note that this example is a combined example of corneal curvature measurement and ocular axial length measurement, but the contacting probe is the contact of an applanation tonometer, the cone lens part for corneal endothelial cell inspection, or the intraocular observation test. It is also possible to apply it to contact lenses for medical purposes and stiff contact electrodes for ERG.

[Effects of the Invention] As described above, according to the present invention, the measurement terminal can be quickly inserted into the measurement position without contacting the subject's elbow, and with the same amount of movement for the left and right eyes by changing only the direction of rotation.゛People can do it. In addition, since the eye to be examined can be observed on a TV monitor not only when measuring corneal curvature but also when measuring axial length, it is possible to check the compatibility between the eye and the probe and the state of the eyelids opened just before contact, ensuring safety and measurement results. This has a significant effect on improving reliability.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of an embodiment of the present invention, Fig. 2 is a partial cross-sectional view of the ) ¥77 part, and Fig. 3 is a diagram showing connections of main components of the embodiment. In the figure, 1...base, 2...movable part, 3...upper and lower rings, 4...
...) Eisaku culm, 5... Measuring switch, 6... Main body,
7... Objective lens, 8... Target light source, 9... Television camera, lO... Television monitor, 11... Guide section, 12... Control calculation section, 13... Printer, 15.
... ;11 moving rotation axis, 16.21.23... gear, 1
8...1 part, 19...probe 22.24...motor, 26...', I'l identification stand, 27...micro switch

Claims (1)

[Scope of Claims] 1. In an ophthalmological apparatus that measures the eye to be examined by bringing a measurement terminal into contact with the eye to be examined, an optical system including an objective lens for observing the anterior segment of the eye to be examined, and an optical axis of the optical system. means for moving the measurement terminal located at an initial position other than the top to a measurement position located on the optical axis of the optical system closer to the eye to be examined than the objective lens; and the measurement probe moved to the measurement position. 1. An ophthalmological apparatus comprising means for moving the child toward the eye to be examined and bringing it into contact with the eye to be examined. 2. The ophthalmologic apparatus according to claim 1, wherein the initial position is in a direction perpendicular to a direction connecting the left and right eyes of the subject. 3. Claim 1 or 2, further comprising a detection means for detecting whether the eye to be examined is a left or right eye, and for rotating the measurement terminal from the initial position to the measurement position in a predetermined direction determined by a detection signal of the detection means. Ophthalmological device as described. 4. The ophthalmologic apparatus according to claim 1, wherein the optical system is also used for measuring corneal curvature of the eye to be examined.