KR101693802B1 - Apparatus for Analyzing Lipid Layer in Tear Film - Google Patents

Apparatus for Analyzing Lipid Layer in Tear Film Download PDF

Info

Publication number
KR101693802B1
KR101693802B1 KR1020150024112A KR20150024112A KR101693802B1 KR 101693802 B1 KR101693802 B1 KR 101693802B1 KR 1020150024112 A KR1020150024112 A KR 1020150024112A KR 20150024112 A KR20150024112 A KR 20150024112A KR 101693802 B1 KR101693802 B1 KR 101693802B1
Authority
KR
South Korea
Prior art keywords
oil layer
tear film
thickness
cornea
unit
Prior art date
Application number
KR1020150024112A
Other languages
Korean (ko)
Other versions
KR20160101481A (en
Inventor
황호식
Original Assignee
한림대학교 산학협력단
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 한림대학교 산학협력단 filed Critical 한림대학교 산학협력단
Priority to KR1020150024112A priority Critical patent/KR101693802B1/en
Publication of KR20160101481A publication Critical patent/KR20160101481A/en
Application granted granted Critical
Publication of KR101693802B1 publication Critical patent/KR101693802B1/en

Links

Images

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/10Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
    • A61B3/1005Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions for measuring distances inside the eye, e.g. thickness of the cornea
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/0008Apparatus for testing the eyes; Instruments for examining the eyes provided with illuminating means
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/10Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
    • A61B3/14Arrangements specially adapted for eye photography

Abstract

The present invention relates to a tear film oil layer analyzer, and more particularly, to a tear film oil layer analyzer that irradiates light emitted from a surface light emitting body to a cornea, captures an interference fringe image caused by reflection or scattering in a tear film oil layer on the surface of the cornea, The present invention relates to an apparatus for analyzing the thickness of an oil layer in a tear film on the surface of a cornea and analyzing a change in thickness of the oil layer according to time.
According to the present invention, it is possible to quantitatively analyze changes in thickness of each region of the oil layer existing in the tear film on the surface of the cornea and a change in thickness with time, by analyzing colors in the captured interference fringe image.

Description

{Apparatus for Analyzing Lipid Layer in Tear Film}

The present invention relates to a tear film oil layer analyzing apparatus, and more particularly, to a tear film oil layer analyzing apparatus that irradiates light emitted from a curved light emitting body onto a cornea, captures an interference fringe image reflected by a tear film oil layer on the cornea surface, The present invention relates to an apparatus for analyzing the thickness of an oil layer existing in a tear film on the surface of a cornea and analyzing a thickness change with time.

Fig. 1 is a diagram illustrating the structure of an eyeball.

Referring to FIG. 1, a tear film 20, a cornea 30, a pupil 40, an iris 50, and a shape muscle 60, which are present on the surface of the cornea, , And a lens 70 are present.

The cornea 30 is composed of an epithelial layer, Bowman's membrane, parenchyma, descemet's membrane, and endothelial layer, and a tear film 20 is present on the surface of the cornea.

Tear (Lacrimal fluid) is wetting the cornea to lubricate and supply oxygen and nutrients to the cornea. In addition, tears can prevent infection by cleaning and antibacterial action of foreign substances, and provide a smooth and transparent optical surface to the cornea to ensure good vision. These tears are weakly alkaline at pH 7.4 and are an isotonic solution of 0.9% sodium chloride (NaCl). The major component is 98.2% water, protein, lipid, mineral and mucin.

The tear film 20 is a thin liquid layer on the surface of the corneal epithelium, ie, the corneal epithelium layer, consisting of the oil layer 21, the aqueous layer 22 and the mucous layer 23.

The lipid layer (21) is the outermost layer of the tear film. It is composed of various kinds of lipids. The oil is secreted from the Meibomian grand. Lipid means an organic compound having properties such as oil or wax, and various lipids constituting the oil layer are wax ester, cholesterol ester, phospholipid, fatty acid, sterol and the like. This oil layer prevents the evaporation of the aqueous layer to maintain the tear film, lubrication between the cornea and the eyelid, and prevents friction.

When the tears evaporate when the eyes are opened, the surface of the cornea will dry, and the corneal epithelium and the tears in the conjunctiva are concentrated, and the difference in the concentration causes the cornea to absorb water.

Dry eye syndrome is one of the most common ophthalmologic diseases, and it is a disease that feels stiffness, foreign body sensation, discomfort, and dizziness. Dry eye syndrome is classified as dry eye syndrome (tear-free dry eye syndrome), tear is normally secreted, but tear is caused by excessive evaporation (dry eye syndrome). In the case of dry eye with evaporation type dry eye syndrome, the oily layer is thin because oily secretion is not well done in my spring spring, and ocular dryness is caused by excessive evaporation of tears. Therefore, taking an oily layer of the tear film and measuring the thickness is a very important test for diagnosing and diagnosing dry eye syndrome, and for determining the treatment method.

Korean Patent Application No. 10-2003-0013775 discloses a Meyer pattern for measuring an accurate curvature of a subject's cornea by easily grasping the exact center of a Meyer pattern formed on an eye cornea of a subject and a method of measuring the corneal curvature using the Meyer pattern .

However, the prior art can only measure the curvature of the cornea and can not measure the thickness of the tear film or the thickness of the oil layer present on the surface of the cornea. A technique is needed to accurately measure the thickness of the tear film layer in diagnosing and diagnosing dry eye syndrome and determining the treatment method.

SUMMARY OF THE INVENTION The object of the present invention is to irradiate light emitted from a curved light emitting body to a cornea, to capture an interference fringe image generated by reflection from a tear film oil layer, and to analyze the color of an interference fringe in a captured image, And an apparatus for analyzing the thickness variation of the oil layer existing in the film and the thickness of the oil layer.

According to an aspect of the present invention, there is provided a curved light emitting device comprising: a curved light emitting part formed in a conical or hemispherical shape and having a viewing hole formed at a central portion of a nipple or a hemisphere of a cone to emit light to illuminate the cornea of the eyeball; A camera unit disposed behind the observation hole and capturing an interference fringe image generated in the tear film oil layer by the irradiated light; And an oil layer analyzer for analyzing the thickness of the tear film oil layer according to the color in the interference fringe image.

Preferably, the camera unit may measure the distance to the central corneal surface and automatically focus the image.

Preferably, the camera unit is capable of automatically focusing the entire interference pattern on the cornea by deepening the depth of focus, and photographing and recording the interference pattern image in chronological order.

Preferably, the apparatus further includes a moving unit that moves the curved light emitting unit and the camera unit back and forth, left and right, and up and down.

Preferably, the oil layer analyzing unit acquires the color of the captured interference fringe image and compares the obtained color with the color distribution table of each thickness to obtain the thickness of the tear film oil layer of the cornea.

Preferably, the oil layer analyzing unit obtains a color according to the position in the captured interference fringe image, compares the obtained color with the color distribution table according to the thickness, and obtains the thickness topographic map of the tear film oil layer according to the position have. The average, maximum and minimum values of the oil layer thickness can be obtained through this.

Preferably, the oil layer analyzing unit acquires a change in hue according to time with respect to the captured interference fringe image, compares the obtained hue with the color distribution table according to the thickness, Thickness variation can be obtained.

According to the present invention, the light emitted from the curved light emitting body is irradiated to the cornea, the interference pattern generated by interference between the light reflected at the interface between the air and the oil layer and the light reflected at the interface between the oil layer and the aqueous layer is photographed, By analyzing the color of the interference pattern in the image, it is possible to quantitatively analyze the change of the thickness of the oil layer present in the corneal tear film and the change with time.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram illustrating the structure of an eyeball; Fig.
2 is a view showing an apparatus for analyzing an oil layer of a tear film according to an embodiment of the present invention.
3 is a view showing an apparatus for analyzing an oil layer of a tear film according to another embodiment of the present invention.
4 is a view showing a camera unit according to the present invention.
5 is a view showing an oil layer analyzer in the present invention.

The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprising" or "having ", and the like, are intended to specify the presence of stated features, integers, steps, operations, elements, parts, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be interpreted as ideal or overly formal in meaning unless explicitly defined in the present application Do not.

In the present invention, the cornea is irradiated with light emitted from a curved light emitting body, an interference pattern generated by interference between light reflected at the interface between the air and the oil layer and light reflected at the interface between the oil layer and the aqueous layer is photographed, The present invention relates to an apparatus for quantitatively analyzing a change in thickness of an oil layer in a corneal tear film and a change in thickness over time by analyzing the color of an interference fringe.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like reference symbols in the drawings denote like elements.

2 is a view showing an oil layer analyzing apparatus for a tear film according to an embodiment of the present invention.

Referring to FIG. 2, the tear film oil layer analyzer 100 includes a curved light emitting portion 110, a camera portion 120, and an oil layer analyzing portion 130 according to an embodiment of the present invention.

The curved light emitting portion 110 is formed in a conical shape and emits light A from the inner surface 111 of the cone to irradiate the cornea of the eye with light. The observation hole 112 is formed at the vertex of the cone of the curved light emitting unit 110 formed in a conical shape so that an image of the interference fringe B generated by the camera unit 120 to be described later reflected by the tear film oil layer can be photographed .

An LED (Light Emitting Diode) (not shown) for emitting white light is disposed on the inner surface of the curved light emitting portion 110, and a translucent glass or plastic cover of opaque color covers the top of the LED to uniformly shine the light into the eyeball.

Of course, a white light source such as a fluorescent lamp, an incandescent lamp, or a halogen lamp may be used as a light source of the curved light emitting unit 110 in addition to the LED.

When the curved light emitting portion 110 irradiates the cornea of the eye with the light A, the light reflected at the interface between the air and the oil layer and the light reflected at the interface between the oil layer and the aqueous layer interfere with each other, And the interference fringe B is photographed by the camera unit 120 through the observation hole 112. [

The camera unit 120 is disposed at the rear of the observation hole 112 of the surface emitting unit 110 and is mounted so that the light reflected at the interface between the air and the oil layer and the light reflected at the interface between the oil layer and the aqueous layer interfere And the interference fringe B is formed.

 The camera unit 120 can capture the interference fringes appearing in the tear film oil layer as a still image or a moving image.

As described above, the tear film is composed of an oil layer, an aqueous layer, and a mucous layer. Since the aqueous layer, the mucous layer and the cornea of the tear film are transparent, the camera section 120 can not focus on the aqueous layer, the viscous liquid layer, or the cornea. Since the interference fringes are generated in the tear film oil layer, automatic focusing in the camera unit 120 is possible.

4 is a view showing a camera unit according to the present invention.

4, the camera unit 120 includes a camera 121, an auto focusing unit 123, and a storage unit 124, and may further include a lens axis adjusting unit 122.

The camera 121 is an element for acquiring an interference fringe image generated in the tear film oil layer, and is implemented with a high-quality camera to discriminate the thickness of the tear film oil layer from the interference fringe image. Since the camera 121 has a generally used configuration, a detailed description thereof will be omitted.

The auto focusing unit 123 precisely measures the distance to the central corneal surface and automatically focuses the image to obtain an interference fringe image generated in the oil layer existing on the corneal surface. In order to obtain a proper interference fringe image, phase difference auto focusing or contrast phase auto focusing is used.

The storage unit 124 records a still image or a moving image captured by the camera 121.

Although not shown in the drawings, the curved light emitting unit 110 and the camera unit 120 can be freely moved forward, backward, left and right, and up and down directions to photograph a desired portion. Since the camera unit 120 is fixedly mounted on the curved light emitting unit 110, the camera unit 120 can be positioned on the front surface of a desired portion of the cornea by moving the curved light emitting unit 110.

For this, the curved light emitting unit 110 may further include a moving unit (not shown) for moving the curved light emitting unit 110 in the forward, backward, leftward, rightward, and upward and downward directions freely. The moving part may be implemented by various mechanisms such as a rail for moving the curved light emitting part 110 to move in the front / back / right / left / up and down directions, a link to the curved light emitting part 110, and a bearing.

In addition, it is also possible to implement a method of acquiring an interference fringe image for each part of the cornea by rotating the lens axis in addition to the above method. For this purpose, the camera unit 120 may further include a lens axis adjusting unit 122.

The lens axis adjusting unit 122 freely moves the lens axis of the camera 121 in the up, down, left, and right directions so that the desired portion of the cornea can be photographed.

The lens axis adjusting unit 122 may include a scanning unit 1221 that divides the cornea surface and moves the lens axis in at least one of horizontal, vertical, and concentric directions.

The lens axis of the camera 121 is automatically and finely moved by the scanning unit 1221 and the auto focusing unit 123 performs focusing automatically so that the cornea is divided into the interference fringes An image can be acquired.

The oil layer analysis unit 130 may acquire the color topography of the tear film oil layer according to the position by acquiring the color according to the position in the photographed interference fringe image and comparing the acquired color with the color distribution table according to the thickness . The average, maximum and minimum values of the oil layer thickness can be obtained through the thickness map.

The oil layer analyzer 135 acquires a change in hue according to a time change in the captured interference fringe image and compares the obtained change in hue with the color distribution table according to the thickness to obtain a tear film oil layer (The average value, the maximum value, the minimum value, or the oil layer thickness at a specific point) and the variation thereof can be obtained.

5 is a view showing an oil layer analyzing unit in the present invention.

5, the oil layer analysis unit 130 includes at least one of the color analysis unit 131, the comparison analysis unit 132, the thickness acquisition unit 133, the comparison storage unit 134, and the quantification analysis unit 135 And may include one or more.

The color analyzer 131 analyzes the pixels of the interference fringe image generated in the tear film oil layer to acquire color information. By analyzing the color values with respect to the pixels of the interference fringe image, it is possible to obtain the color values in each part. Of course, the color value may be analyzed for each pixel of the interference fringe image, but the interference fringing image may be divided into the analysis area having a predetermined confined area, and the average color value in the divided analysis area may be obtained.

The comparison and analysis unit 132 compares the color value of each pixel in the interference fringe image acquired by the color analysis unit 131 or the average color value in the analysis area to the table storage unit 1341 of the comparison storage unit 134 And obtains data that matches the color value or the average color value in the interference fringe image.

An example of the correspondence relationship between the color distribution and the oil layer thickness in the interference fringing image generated in the oil layer is as follows. : (1) White (estimated lipid layer thickness 30 nm), (2) Gray / white (45 nm), (3) Gray (60 nm), (4) Gray / 90 nm), (6) Yellow / brown (105 nm), (7) Brown / yellow (120 nm) / brown (165 nm), and (11) Blue (180 nm).

The relationship between the color distribution and the oil layer thickness is not limited to the above example, and can be appropriately adjusted according to the individual age, sex, race, body weight, and the like.

The thickness obtaining unit 133 analyzes the obtained matching data to obtain information on the thickness of the tear film oil layer in each part of the cornea and stores it in the history storing unit 1342 of the comparison storing unit 134 .

Of course, since the interference fringe image may be a continuous still image or a moving image photographed in chronological order, the color analyzer 131, the comparative analyzer 132, and the thickness gauge 133 may generate the tear film oil layer The information on the thickness of the tear film oil layer can be acquired for each time and for each position of the cornea by acquiring the change of color according to the time change in the interference fringe image in the tear film oil layer by analyzing the interference fringe image of the tear film oil layer.

The quantification analysis unit 135 analyzes the change in the thickness of the tear film oil layer obtained at each time and at each position, thereby determining the thickness of the tear film oil layer at each position of the cornea, the thickness change with time, and the blinking moment Quantitative information on the thickness variation of the tear film oil layer at each position of the cornea can be obtained before and after.

Of course, the quantification analyzer 135 compares the history data recorded in the past with the current data analyzed in accordance with the currently captured interference fringe image for each subject, thereby not only a short blinking time but also a tear film oil layer Can be obtained.

Also, the quantification analyzer 135 may analyze and convert information on the thickness change of the tear film oil layer obtained at each time to generate a graph image of the thickness change of the tear film oil layer with time. By displaying the time variation on the x-axis and the oil layer thickness on the y-axis in the graphical image, the inspector can intuitively perceive the change in oil layer thickness.

The comparison storage unit 134 stores inspection data of each subject and includes a table storage unit 1341 and a history storage unit 1342.

The table storage unit 1341 stores a color distribution table for each thickness corresponding to the color distribution of the interference fringe and the thickness of the tear film oil layer. The history storage unit 1342 stores the color distribution table for each thickness of the interference fringe image And result data according to past and present inspections. The result data according to the inspection means information obtained by analyzing the interference fringe image and quantified by the time and position of the thickness of the tear film oil layer obtained.

3 is a view showing an apparatus for analyzing a tear film oil layer according to another embodiment of the present invention.

The tear film oil layer analyzer 100 of FIG. 3 differs from the tear film oil layer analyzer 100 of FIG. 4 only in the configuration of the curved surface light emitter and the remaining components are the same.

The curved light emitting portion 113 of FIG. 3 is formed in a hemispherical shape and emits light A at the hemispherical inner surface 114 to irradiate light to the cornea of the eyeball. An observation hole 115 is formed at the center of the hemispherical surface emission unit 110 so that the camera unit 120 can capture the interference pattern B generated in the oil layer of the corneal tear film.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. Accordingly, the scope of protection of the present invention should be construed in accordance with the following claims, and all technical ideas within the scope of equivalents and equivalents thereof should be construed as being covered by the scope of the present invention.

100: Oil layer analyzer
110, and 113:
112, 115: observation hole
120:
121: camera
122: Lens shaft adjusting part
1221: Scanning section
123: auto focusing part
124:
130: oil layer analysis section
131: color analysis unit
132:
133: thickness obtaining section
134:
1341:
1342: History storage unit
135: Quantification analysis section

Claims (6)

  1. A curved light emitting portion which is formed in a conical or hemispherical shape and emits light from the inner surface to irradiate light to the cornea of the eyeball, the observation hole being formed at the center of the nipple or hemisphere of the cone;
    An interference fringe image generated at the tear film oil layer by the irradiated light is photographed. The focal depth is deep to automatically focus the entire interference fringes on the cornea. The interference fringe image is photographed in chronological order A camera unit for recording an image; And
    The change of color according to time is obtained from the captured interference fringe image, and the obtained color change is compared with the color distribution table according to the thickness, and information on the thickness of the tear film oil layer according to the time is obtained for each hour and the cornea And an oil layer analyzing unit for acquiring the oil layer analyzing unit for each position,
    The oil layer analyzing unit analyzes the change in the thickness of the tear film oil layer obtained at each time and at each position so that the thickness of the tear film oil layer at each position of the cornea and the thickness change with time and the change in the thickness before and after the blinking moment And a quantification analyzer for obtaining quantified information on the thickness variation of the tear film oil layer at each position of the cornea.
  2. The camera system according to claim 1,
    And measuring the distance to the central corneal surface and automatically focusing the tear film.
  3. delete
  4. 2. The apparatus of claim 1,
    Further comprising a moving unit for moving the curved light emitting unit and the camera unit back and forth, right and left, and up and down.
  5. 3. The apparatus according to claim 2,
    And a lens axis adjusting unit for dividing the cornea surface and moving the lens axis in at least one of the horizontal, vertical and concentric directions so that the desired portion of the cornea is photographed. The tear film oil layer Analysis device.
  6. The apparatus of claim 1, wherein the quantization /
    By comparing the history data recorded in the past with the current data analyzed according to the currently captured interference fringe image for each subject, data on the blinking time of the eyes and the average thickness change of the tear film oil layer over a long period of time are obtained Wherein the tear film oil layer analyzing apparatus comprises:
KR1020150024112A 2015-02-17 2015-02-17 Apparatus for Analyzing Lipid Layer in Tear Film KR101693802B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020150024112A KR101693802B1 (en) 2015-02-17 2015-02-17 Apparatus for Analyzing Lipid Layer in Tear Film

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020150024112A KR101693802B1 (en) 2015-02-17 2015-02-17 Apparatus for Analyzing Lipid Layer in Tear Film

Publications (2)

Publication Number Publication Date
KR20160101481A KR20160101481A (en) 2016-08-25
KR101693802B1 true KR101693802B1 (en) 2017-01-06

Family

ID=56884655

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1020150024112A KR101693802B1 (en) 2015-02-17 2015-02-17 Apparatus for Analyzing Lipid Layer in Tear Film

Country Status (1)

Country Link
KR (1) KR101693802B1 (en)

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8092023B2 (en) * 2009-04-01 2012-01-10 Tearscience, Inc. Ocular surface interferometry (OSI) methods for imaging and measuring ocular tear film layer thickness(es)

Also Published As

Publication number Publication date
KR20160101481A (en) 2016-08-25

Similar Documents

Publication Publication Date Title
JP4694025B2 (en) Eye characteristics measuring device
JP4113005B2 (en) Eye examination equipment
US9526416B2 (en) Ophthalmologic apparatus
JP5964932B2 (en) Ocular surface interference spectroscopy (OSI) apparatus, system and method for imaging, processing and / or displaying ocular tear film and / or measuring ocular tear film layer thickness
JP4621496B2 (en) Line scan ophthalmoscope
US6267477B1 (en) Three dimensional imaging apparatus and a method for use thereof
JP2004535880A (en) Apparatus and method for testing and quantifying cataracts
US7309128B2 (en) Automated stereocampimeter and related method for improved measurement of the visual field
JP4824400B2 (en) Ophthalmic equipment
JP5665181B2 (en) Tear film measurement
JP2006341094A (en) Method for operating ophthalmological analysis system
Patel et al. Laser scanning in vivo confocal microscopy and quantitative aesthesiometry reveal decreased corneal innervation and sensation in keratoconus
JP2006528787A (en) Method and apparatus for online contact lens evaluation
US7470025B2 (en) Ophthalmic apparatus
US20150351631A1 (en) Systems and methods for improved ophthalmic imaging
JP4458935B2 (en) Perimeter
JP6144429B2 (en) Eye tracking device operating method and eye tracking device performing active illumination control to improve eye tracking robustness
JP4990133B2 (en) Reflection microscope for examination of corneal endothelium and method of operating the microscope
JP5209341B2 (en) Non-contact tonometer
US6663242B1 (en) Simultaneous, wavelength multiplexed vision screener
EP2413778B1 (en) Instrument for eye examination
WO2002064030A1 (en) Eye characteristics measuring device
US7810928B2 (en) Evaluating pupillary responses to light stimuli
US7854509B2 (en) Vision screener
US4423931A (en) Fundus camera accessory for analysis of the ocular fundus contour

Legal Events

Date Code Title Description
A201 Request for examination
E902 Notification of reason for refusal
E701 Decision to grant or registration of patent right
GRNT Written decision to grant