JPS63216529A - Ophthalmic apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is applicable to multiple measurements and inspections with different working distances, such as a device that combines the functions of measuring corneal refractive power and measuring axial length. The present invention relates to an ophthalmological device having functions.

[Conventional technology]

In cataract surgery, in which a cloudy crystalline lens is extracted and an artificial crystalline lens is inserted, when selecting an artificial lens with an appropriate refractive power, the corneal refractive power and axial length are measured, and these values are calculated using a certain formula. A method of calculating refractive power is generally used.

[Problem that the invention seeks to solve]

However, in the past, corneal refractive power and axial length were measured using separate devices, which not only required a large installation space but also required the patient with poor eyesight to move 8 times, making it difficult to measure the corneal refractive power and axial length. There were problems such as the amount of time it took.

Therefore, there is a desire to combine the function of measuring corneal refractive power and the function of measuring ocular axial length, but if you try to move the sliding table in the optical axis direction to perform the two measurements, it will be difficult to move the sliding table in the direction perpendicular to the optical axis. The problem was that the alignment state of the images would be disrupted.

An object of the present invention is to provide an ophthalmologic apparatus that solves the above problems.

[Means for solving problems]

As a means of solving the above problem, as will be described in detail in the embodiments described below, a probe holder 8. Sliding guide member 10. Sliding operation lever 11. Furthermore, a tension spring 9 is provided.

[For production]

In such a configuration, when measuring corneal refractive power, the probe for measuring axial length is retracted to the rear so that it does not hit the subject's eyes or face; Bring the tentacle close to the eye to be examined and bring it into contact.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

1 to 3 are diagrams showing one embodiment of the present invention, in which a first measurement system for measuring the corneal refractive power of the eye E to be examined and the eye of the eye E to be examined are installed in a main body supported on a sliding table. It is equipped with a second measurement system for determining the axial length.

The first corneal refractive power measurement system includes a projection target light source 1, a movable mirror 2. Objective lens 3. It is composed of a two-dimensional image sensor 4. Here, the projection index light source 1 is, for example, a plurality of light emitting diodes arranged on a circumference centered on the measurement optical axis as shown in FIG. projected on. Then, a corneal reflection image of the projection target light source 1 is formed by the convex mirror action of the cornea, but since the shape of the corneal reflection image changes depending on the radius of curvature of the cornea and the degree of astigmatism, it is necessary to detect this. It is well known that corneal refractive power, corneal astigmatism, and axial angle can be determined by

In this embodiment, as described above, the corneal reflected image of the projection target light source 1 is detected by being imaged on the two-dimensional image sensor 4 by the objective lens 3 via the movable mirror 2. This detection signal is processed by an electric circuit (not shown), and further arithmetic processing is performed to determine corneal refractive power, corneal astigmatism, and axial angle. The two-dimensional image sensor 4 is used not only for detecting measurement signals but also for observing the anterior segment of the eye E to be examined.
This allows alignment to be performed by operating a well-known sliding table 6 while observing the anterior segment of the eye on a monitor 5.

Next, the second axial length measurement system uses the probe 7. Probe holder 8
．． Tension spring9. It is composed of a sliding guide member 10 and a sliding operation lever 11.

The probe 7 contains an ultrasonic oscillator and a receiver, and is connected to an electric circuit section (not shown) via a cable 12.

In this embodiment, when measuring the corneal refractive power, the probe 7 is retracted behind the movable mirror 2 so as not to obstruct the optical path for measuring the corneal refractive power, but when measuring the axial length, the probe 7 is moved as shown in FIG. By tilting the movable mirror 2 and sliding the sliding operation lever 11 forward, the probe 7 is made to protrude in a direction approaching the eye E to be examined. At this time, the slide table 6 is fixed (note that the slide table 6 will be fixed more securely if the locking means of the slide table 6 is used), so there is no need to readjust the alignment by operating the slide operation lever 11. It's good. Note that the tip of the probe 7 can be brought into contact with the cornea of the eye E by finely aligning the sliding table 6 as necessary.

The probe 7 is held by a probe holder 8 so as to be able to slide accurately with low frictional force in the front-rear direction, that is, in the direction of the measurement optical axis, and is biased forward by a weak tension spring 9.

Therefore, even if the probe 7 is brought too close to the eye to be examined, the probe 7 will move backward against the weak force of the tension spring 9, and the probe 7 will move against the cornea of the eye E to be examined. The end face of 7 is brought into contact with a weak constant pressure so as not to forcibly indent the cornea or cause any harm.

With the probe 7 in contact with the cornea of the eye to be examined, ultrasonic pulses are emitted from the tip of the probe 7, and by receiving reflected echoes from the retina of the eye E, the ultrasound pulse is transmitted from the corneal surface to the retina. It is well known that the axial length of the eye can be detected and a measured value obtained.

After measuring the corneal refractive power and axial length of the eye E as described above, these values can be calculated using empirically obtained formulas.
It is also well known that the refractive power of an artificial crystalline lens can be calculated.

When measuring the axial length by flipping up the probe 7,
The probe is rotated forward as shown by the arrow, and the probe 7 is not protruded forward while the sliding table 6 is fixed, so that the probe approaches the cornea of the eye E to be examined.

FIG. 5 shows another embodiment in which the measurement optical axis of the corneal refractive power measurement system and the central axis of the probe 7 of the ocular axial length measurement system do not coincide (parallel and eccentric).

The probe 7 of the axial length measurement system is placed above the measurement optical axis of the corneal refractive power measurement system, and this probe 7 is attached to the probe holder 8.
is held in the same PJ structure as the first embodiment,
When measuring the ocular axis length, the central axis of the probe 7 is aligned with the measuring optical axis by displacing it by S in the plane perpendicular to the optical axis, and the probe 7 is moved toward the eye to be examined along the sliding guide member 10. When moving and measuring the corneal refractive power, the probe 7 is configured to be retracted to the rear.

In this example, when measuring the ocular axial length after measuring the corneal refractive power, it is necessary to readjust the height of the measuring section (for example, displacing the sliding table 6 by S in the plane perpendicular to the optical axis). , which has the advantage of simplifying the structure.

(Effects) As described above, according to the present invention, it is possible to combine multiple measurement and inspection functions with different working distances into one device, and if the alignment is adjusted in one measurement, in the other measurement. There is no need to perform alignment adjustment again.

Further, according to the present invention, the detection terminal is configured to protrude toward the eye to be examined, and the detection terminal is inserted from the examiner's side.

[Brief explanation of the drawing]

1 to 3 are explanatory diagrams of the first @ embodiment, FIG. 4 is an explanatory diagram of the second embodiment, and FIG. 5 is an explanatory diagram of the third embodiment. 1 in the figures is a projection index The light source 3, the objective lens 4, the two-dimensional image sensor 5, the TV monitor 7, the probe 8, the probe holder 9, the tension spring 10, and the sliding guide member 11 are a sliding operation lever. Figure 4

Claims (6)

[Claims] (1) A first detection system that detects first eye information at a relatively long working distance with respect to the eye to be examined is contained in the main body supported on a sliding table, and a detection terminal is brought into contact with the eye to be examined. and a second detection system that detects the second eye information, and the second detection system detects the second eye information without moving the sliding table in the optical axis direction when switching between the first detection system and the second detection system. An ophthalmologic apparatus comprising means for moving a detection terminal of the system in the optical axis direction. (2) The ophthalmological apparatus according to claim 1, wherein the detection terminal of the second detection system is biased toward the eye to be examined. (3) The ophthalmologic apparatus according to claim 1, wherein when switching from the first detection system to the second detection system, the detection terminal of the second detection system is displaced by a predetermined distance within the perpendicular to the optical axis. (4) The ophthalmologic apparatus according to claim 3, wherein the displacement is performed on a sliding table. (5) the first subject eye information is corneal refractive power information;
The ophthalmologic apparatus according to claim 1, wherein the second eye information is axial length information. (6) The ophthalmologic apparatus according to claim 5, wherein the detection terminal of the second detection system includes an ultrasonic transmitter and a receiver.