KR101538129B1 - Standard lens for eye refractometer - Google Patents

Abstract

The present invention relates to a standard lens for an eye refractometer and, more particularly, a standard lens used for correcting an eye refractormeter which is an apparatus including a continuous or digital reading device used for measuring the difference of the refractive index of the eye. For this, provided is the standard lens whose rear side is roughly polished to attach a reticle or the standard lens whose rear side is optically polished to attach the reticle. Thereby, the focal distance of the standard lens is precisely measured.

Description

[0001] STANDARD LENS FOR EYE REFRACTOMETER [0002]

More particularly, the present invention relates to a standard lens used for calibrating a refractive power system for an eye, which is a device having a continuous or digital reading device, which is used for measuring the refractive power of an eye, will be.

The ophthalmologic examination includes a visual acuity test, tonometry, measurement of corneal curvature, fundus photography, and a slit lamp. A visual acuity test is a test to determine the degree of visual acuity at a long distance. It measures uncorrected visual acuity or corrected visual acuity. The IOP test is a test to measure changes in the surface reflections of the cornea using compressed air. This glaucoma screening is performed by measuring the intraocular pressure of the eyeball. The autorefractor is a test for correcting visual acuity by measuring spherical power, spherical power, and astigmatic direction of the eye and confirming primitive, myopia, and astigmatism. Fundus photography is the examination of the retina behind the eyeball. The slit lamp microscope is used to check the conjunctiva, cornea, anterior chamber, lens and vitreous body by adjusting the angles of the eyes to be examined together with the observation microscope while varying the width and length of the illumination light.

At this time, the refractive power of the eyeball in the automatic refraction test is measured as the diopter (D), which is the inverse of the focal distance of the eyeball (distance from the lens to the focal point).

The refractive power system of the optometry is used for the examination of the refractive power of the eye and the eye diopter of the subject is specified. Light from a distance travels through the lens or lens, refracts and collects at a point behind the lens. The closer this focal point is, the higher the refractive power and the higher the diopter. If the light passing through the lens or lens goes beyond 1 m, the focal length is 1 m and the power is 1 diopter. If the focal length is 2 m, it is 0.5 diopter. The larger the absolute value of the diopter, the stronger the refractive power of the lens or the lens.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram showing the principle of a refractive power meter for an eye. Fig. 1, the optometric ophthalmoscope 1 includes an image source 10, an objective lens 20, an aperture 30, a light source 40, a slit 50, and a CCD camera 60 Lt; / RTI > When the eyeball 2 to be inspected is placed on one side of the optometry refractive power system, astigmatism (non-astigmatism) through the diameter between the pinhole image and the shape of the six pinhole images of the slit 50 observed by the CCD camera 60 ) And diopter (diameter between the holes). FIG. 2 is a photograph showing six dot shapes observed by the CCD camera 60, and FIG. 3 is a schematic diagram showing a principle of measuring astigmatism and diopter in six dot shapes observed by the CCD camera 60.

In the human eye, the larger the diopter value, the greater the degree of myopia or hyperopia. Primitives should be focused with a convex lens, and nearsighted should be focused with a concave lens. Therefore, nearsightedness is negative (-) diopter and primitive is represented by positive (+) diopter.

In the case of myopia, it is classified as myopia when it is below -3D, moderate myopia when it is -3D to -6D, and high myopia when it is above -6D. If the glasses are not used, the time is 0D. In the case of primitive, it is classified as a primitive primitive when + 3D or less, a moderate primitive when + 3D to + 6D, or a primitive primitive when it is + 6D or more.

Method and device for synchronous mapping of the total refraction non-homogeneity of the eye and its refractive components, US 6,409,345, Tracey Technologies, LLC. Automatic visibility correction viewfinder system for optical devices, US 4,828,381, Asahi Kogaku Kogyo Kabushiki Kaisha.

In order to calibrate the refractive power meter for the optometry, a standard lens which can be a standard of a specific diopter is required. FIG. 4 is a photograph showing a conventional standard lens, and FIG. 5 is a side sectional view showing a conventional standard lens. As shown in Figs. 4 and 5, the standard lens may be made of polymethylmethacrylate (PMMA) or optical glass. The front surface is also polished to an optical finish. As shown in FIG. 5A, the conventional standard lens may have a cylindrical shape with a refracting surface of about R8 (mm) in front, and may have a semi-circular toric contact lens Toric contact lens, for example.

Also, in the prior art, it has been defined in ISO 10342: 2002 and ISO 10342: 2003 that the rear plane of these standard lenses is roughly polished in lightly frosted (paint dark gray) so as to serve as a retina.

Fig. 6 is a schematic diagram showing a state in which a standard lens 3 is mounted on an ophthalmologic refractive power system and tested. Fig. As shown in FIG. 6, the standard lens 3 of the standard diopter that can replace the eye of a person is used to perform a test to ensure the accuracy of the measurement of the spherical vertex power of the optometric optical system.

The refractive power of a standard lens is a function of its length (1), the radius of the spherical surface (R), the refractive index of the material (n) and the wavelength of light (λ) , Because of the spherical aberration of the standard lens, the conventional ISO regulations stipulate that the refractive power of the standard lens should be predicted in the following manner.

a) Measure the refractive power using an optical bench or a precision refractometer fitted to an optical system equipped with a refractive head.

b) Measure the length, the spherical diameter of the front surface, and the refractive index of the material, and measure the refractive power using ray tracing in the following manner. Find a point on the optical axis that forms a minimum square root (rms) point on the back of the scattered light of the test instrument, with a light flux filling the pupil of 3 mm in diameter in a plane tangent to the refractive surface of the test instrument. Then, the refractive power of the standard lens is given by the following equation.

Where P is the refractive power (diopter) of the displayed standard lens and d is the distance in m from the refractive surface to the point source (KS P ISO 10342: 2002, ISO 10342: 2003).

However, the above standard lens refractive power measurement is only a predicted value, which is not correct. In addition, if the rear plane of the standard lens is configured in a glassy state, the reflected light is not clear, so that it is difficult to correct the refractive power of the eye. In addition, there is a problem that the focal plane of the standard lens is configured to be in a glass state and the focal length or the diopter of the standard lens can not be accurately measured.

Accordingly, the present invention has been made to solve the above-described problems.

SUMMARY OF THE INVENTION An object of the present invention is to provide a reticle attaching type reticle mounting apparatus capable of attaching a reticle to a plane after rough polishing or optically polishing (polishing) a rear plane and attaching a reticle to the polished rear face to accurately measure a focal distance In providing a standard lens.

Hereinafter, specific means for achieving the object of the present invention will be described.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a light source device and a method of manufacturing the same, in which a cylindrical main body is constructed so that incident light incident on a front surface portion or a rear surface portion can propagate in a longitudinal direction. A refracting portion provided in a front portion of the main body and configured to be hemispherical so as to refract the incident light; And a reticle formed on one side of the main body, the reticle being formed on an optical axis of the incident light, wherein the reticle is used for calibrating a refractive power system for an eye. The focal length of the standard lens can be precisely measured by the organic coupling between the main body, the refracting portion and the reticle.

The reticle may be formed on a rear surface of the main body. When the reticle is formed on the rear face portion, an effect that the reticle phase can be formed more clearly occurs.

The reticle may further include a cross scale having a plurality of graduations having a specific thickness in a cross shape. In this case, the specific thickness is set to 10 μm in one embodiment of the present invention. The reticle including such a cross-shaped graduation is easy to find the center of the reticle, and has the effect of measuring the focal distance more precisely.

The reticle may further include: a cross grid having a plurality of graduations having a specific thickness in a cross shape; And a circle scale in which at least one scale having a specific thickness is formed in a circular shape. The reticle to which the circle scale and the cross shape scale are combined is easy to determine the center of the reticle and determine whether or not the focus is formed, and it is possible to measure the focal distance more precisely.

The rear surface of the main body may be optically polished so that the incident light may be transmitted, and the incident light may be incident on the rear surface of the main body to proceed to the front surface of the main body. When the rear portion of the main body is optically polished (polished), the focal distance can be measured based on straight-line light, not reflected light.

Further, the rear portion of the main body may be rough-polished. When the rear portion of the main body is rough-polished, the rear portion of the rough-polished main body can replace the retina of the actual eyeball, and an accurate measurement of the focal distance can be performed by the reticle while realizing an environment similar to the measurement of the actual refractive power of the eyeball. The effect is generated.

As described above, the present invention has the following effects.

First, according to one embodiment of the present invention, there is an effect that a focal length of a standard lens can be precisely measured.

Second, according to the embodiment of the present invention, there is an effect that the correction of the refractive power for the optometry can be performed precisely.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate preferred embodiments of the invention and, together with the description, And shall not be interpreted.
1 is a schematic diagram showing the principle of an optometric ophthalmologic power meter,
FIG. 2 is a photograph showing six dot-shaped pinhole images observed by the CCD camera 60,
FIG. 3 is a schematic diagram showing a principle of measuring astigmatism and diopter with six point-shaped pinhole images observed by the CCD camera 60
4 is a photograph showing a conventional standard lens,
5 is a side sectional view showing a conventional standard lens,
6 is a schematic diagram showing a state in which a standard lens is mounted on a refractive power meter for an eye,
7 is a side sectional view showing a standard lens according to an embodiment of the present invention,
Figure 8 is an embodiment of a reticle attached to a rear portion of a standard lens according to an embodiment of the present invention,
9 is a schematic diagram showing an apparatus for measuring a diopter of a standard lens according to the first embodiment of the present invention,
10 is a schematic diagram showing an apparatus for measuring a diopter of a standard lens according to a second embodiment of the present invention,
11 is a schematic diagram showing an apparatus for measuring a diopter of a standard lens according to a third embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following detailed description of the operation principle of the preferred embodiment of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may unnecessarily obscure the subject matter of the present invention.

The same reference numerals are used for portions having similar functions and functions throughout the drawings. Throughout the specification, when a part is connected to another part, it includes not only a case where it is directly connected but also a case where the other part is indirectly connected with another part in between. In addition, the inclusion of an element does not exclude other elements, but may include other elements, unless specifically stated otherwise.

Standard lens

With reference to a standard lens, Figure 7 is a side cross-sectional view illustrating a standard lens in accordance with an embodiment of the present invention. As shown in FIG. 7, the standard lens 5 according to one embodiment of the present invention may be formed in a columnar shape, and one surface may be a hemispherical surface providing a refractive power. Further, the other surface of the standard lens 5 according to an embodiment of the present invention may be configured not only to rough grinding of the prior art but also to optical polishing (polishing) so that light can pass therethrough. In an embodiment of the present invention, The present invention proposes a method for measuring the position of an image plane by forming an image of a reticle by attaching a reticle to both the plane after optical polishing and the plane after rough polishing.

Figures 7a) and 7b) show a standard lens in which the backside is rough-polished and a reticle is attached to it, according to one embodiment of the present invention, Figures 7c) and 7d) A standard lens is illustrated in which the back side is optically polished (polished) according to the example and attached to the reticle on its side.

Also, a reticle 7 (Reticle) may be formed on one surface or the other surface of the standard lens 5 according to an embodiment of the present invention. 8 is a schematic diagram showing a reticle according to an embodiment of the present invention. As shown in FIG. 8, the reticle 7 according to an embodiment of the present invention may be configured in various forms. As the reticle 7 is formed on at least one of the one surface and the other surface of the standard lens 5, the refractive power of the following standard lens diopter measuring apparatus can be easily measured.

As shown in FIG. 8A, the reticle 7 of the standard lens 5 according to an embodiment of the present invention may be formed in a cross shape having a thickness and an interval of 10 μm. 8 (b), the reticle 7 of the standard lens 5 according to an embodiment of the present invention further includes a circular scale having a thickness of 10 [mu] m and a diameter of 4 mm and 8 mm can do.

With reference to one specific embodiment of such a standard lens, one embodiment of the focal length, diopter, and length of a standard lens is shown in Table 1 below.

Focal length (cm) Diopter (D) Length (mm) +4.0 +25 16.91 +5.0 +20 17.91 +6.6 +15 19.03 +10 +10 20.30 +20 +5.0 21.76 +40 +2.5 22.56 infinity 0 23.43 -40 -2.5 24.38 -20 -5.0 25.39 -10 -10 27.71 -6.6 -15 30.50 -5.0 -20 33.90 -4.0 -25 38.16

Hereinafter, a standard lens diopter measuring apparatus using a standard lens 5 according to an embodiment of the present invention will be described.

Diopter measuring device of standard lens

9 is a schematic diagram showing an apparatus for measuring a diopter of a standard lens according to a first embodiment of the present invention, in relation to a diopter measurement apparatus for a standard lens according to the first embodiment. As shown in FIG. 9, the apparatus for measuring a diopter of a standard lens according to the first embodiment of the present invention may include an adjusting telescope 120, a light source 110, a collimator 100, and the like. The standard lens 3 used in the diopter measurement apparatus of the standard lens according to the first embodiment may be a standard lens whose back surface is optically polished.

The light source 110 is a structure for irradiating the rear surface of the standard lens 3 with light such as LED light or laser light in the longitudinal direction of the standard lens 3. The light irradiated from the light source 110 can be transmitted to the spherical front surface of the standard lens 3 through the rear surface of the polished standard lens 3 and the light source 110 can pass through the rear surface of the standard lens 3, The spherical front surface of the standard lens 3 is irradiated with light, so that the adjusted telescope 120 can easily measure the diopter of the standard lens 3.

The collimator 100 is an optical device that is disposed in front of an LED light source where light dispersion occurs to form a parallel light beam. A refraction type or a reflection type collimator can be selectively used depending on the measurement environment. The LED light passing through the collimator 100 is formed close to a parallel light beam and irradiated to the rear portion of the standard lens 3. When the LED light close to the parallel light beam passes through the standard lens 3 of 0 diopter, it still proceeds to the parallel light ray.

The adjustment telescope 120 is configured to confirm whether or not the standard lens 3 is focused using light that has passed through the standard lens 3 in the longitudinal direction. The adjustment telescope 120 can confirm whether the target light is focused by the naked eye or the CCD camera and the user can confirm the focal distance of the standard lens 3 through the distance between the adjusted telescope 120 and the standard lens 3. [ have.

10 is a schematic diagram showing an apparatus for measuring a diopter of a standard lens according to a second embodiment of the present invention, in relation to the apparatus for measuring a diopter of a standard lens according to the second embodiment. 10, the apparatus for measuring a diopter of a standard lens according to the second embodiment of the present invention includes a control telescope 120, a light source 110, a collimator 100, and the like, as in the first embodiment of the present invention. And in addition, the reticle 130 may be attached to the front or rear of the standard lens 3. The apparatus for measuring the diopter of a standard lens according to the second embodiment of the present invention in which a reticle is attached to the front and rear of the standard lens 3 is further optically polished (polished) according to an embodiment of the present invention, and a reticle Can be used for an attached standard lens.

When the reticle 130 is constructed according to the second embodiment of the present invention, there is an effect that the user can confirm the focal distance of the standard lens 3 more accurately.

11 is a schematic diagram showing an apparatus for measuring a diopter of a standard lens according to a third embodiment of the present invention, in relation to the apparatus for measuring a diopter of a standard lens according to the third embodiment. 11, the apparatus for measuring a diopter of a standard lens according to the third embodiment of the present invention includes an adjustment telescope 120, a light source 110, a collimator 100, and the like, as in the first embodiment of the present invention. And a device for measuring the distance by a laser interferometer (140), a linear scale, or the like may further be formed. When the reticle 130 is formed according to the third embodiment of the present invention, the focal distance of the standard lens 3 can be confirmed more accurately by the user.

12 is a schematic diagram for calculating the diopter of a standard lens using a diopter measuring apparatus of a standard lens according to an embodiment of the present invention. 12, the focal length L of the standard lens is precisely measured by the apparatus for measuring diopter of a standard lens according to an embodiment of the present invention, and the reciprocal of the measured focal length L is taken, D) can be calculated.

As described above, those skilled in the art will appreciate that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention.

1: Diopter measuring device
2: eyeball
3: Standard lens
10: Image source
20: Objective lens
30: Aperture
40: light source
50: slit
60: CCD camera
100: collimator
110: Light source
120: Adjustable telescope
130: Reticle
140: Laser interferometer

Claims (6)

A cylindrical main body configured to allow incident light incident on a front surface or a rear surface to be transmitted in a longitudinal direction;
A refracting portion provided in a front portion of the main body and configured to be hemispherical so as to refract the incident light; And
A reticle in the form of a scale formed on one side of the main body and formed on the optical axis of the incident light;
/ RTI >
Wherein the standard lens is mounted on an outer side of an eyepiece lens for optometry of an ophthalmic refractive power system and is used in place of the eye of the subject when calibrating the ophthalmic refractive power system.
The method according to claim 1,
Wherein the reticle is formed on a rear portion of the main body.
The method according to claim 1,
The reticle,
A cross scale in which a plurality of graduations having a specific thickness are formed in a cross shape;
≪ / RTI >
The method according to claim 1,
The reticle,
A cross scale in which a plurality of graduations having a specific thickness are formed in a cross shape; And
A circle scale in which at least one scale having a specific thickness is formed in a circular shape;
≪ / RTI >
5. The method according to any one of claims 1 to 4,
Wherein the rear surface of the main body is optically polished so that the incident light is transmitted therethrough, and the incident light is incident on the rear surface portion of the main body to proceed to the front surface portion of the main body.
5. The method according to any one of claims 1 to 4,
And a rear surface portion of the main body is rough-polished.

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