CN109431453B

CN109431453B - Eye vision instrument for objective vision general survey

Info

Publication number: CN109431453B
Application number: CN201811307309.XA
Authority: CN
Inventors: 王光霁; 王勇; 瞿佳; 吕帆; 陈洁
Original assignee: Eye Hospital of Wenzhou Medical University
Current assignee: Eye Hospital of Wenzhou Medical University
Priority date: 2018-11-05
Filing date: 2018-11-05
Publication date: 2021-09-28
Anticipated expiration: 2038-11-05
Also published as: CN109431453A

Abstract

The invention provides an eye vision instrument for objective vision general survey, which comprises: the plate and several optical components, light source, front slit (front view as 4), principal focus, positive lens, beam splitter, virtual image, (front view as 10) will be away from its initial position 3. The light beam is diverged by the virtual image 9, turned by about 90 degrees via the thin slide 7 and projected toward both eyes 13 of the examinee. The reflected beam appears to be emitted by its virtual image 11 (front view as at 12), a small target is placed in the posterior cleft 14 (top view as at 15) outside the principal focal point 6 of the positive lens 5, and it is rotated 90 degrees by the thin slide 7 through the real image 16 (front view) formed by the positive lens 5 and focused on the subject's forehead. The clear real image 16 determines the examination distance between the instrument and the subject. In the checking process, the nano sticker 19 is installed on the back of the panel 1, and when the panel small hole 8 is aligned with the camera 18 of the smart phone, the nano sticker 19 is attached to the smart phone in a clinging mode.

Description

Eye vision instrument for objective vision general survey

Technical Field

The invention relates to an eye vision instrument for objective vision general survey, in particular to an eye vision instrument which can be attached to instruments with camera functions, such as a smart phone, a digital camera, an iPad and the like, and is used for detecting eye abnormality causing amblyopia of children.

Background

2-4% of the world population suffers from amblyopia, and the incidence rate is the same in China. Amblyopia is mostly caused by poor imaging of the eyes present at infancy, which may occur with discordance of the visual axes of both eyes (strabismus); relatively high refractive errors, particularly astigmatism or hyperopia; higher myopia or hyperopia (refractive error) in one eye than in the other; or clouding of the refractive medium of the eye, such as congenital cataract or ocular tumors. Since the mechanism of occurrence of amblyopia involves the brain, vision is not immediately restored after the pathogenic factor is released, and visual training is required for improving vision. Early detection of the causative factors of amblyopia is crucial to improving the success rate of treatment. If not treated, amblyopia will continue to be adult, and the success rate of treating amblyopia of adults is very low. Amblyopia in young children is difficult to detect, and it is not practical to perform a comprehensive eye examination for each child to find out eye abnormalities. Therefore, it is a necessary and feasible approach to develop a vision screening for all children as early as possible.

Existing visual screening is performed when the child reaches the age of school, but the best age of treatment has been missed. Most of the currently used visual screening devices and methods are subjective, requiring accurate responses by children, which is unlikely to be done by young children. Subjective vision screening is the detection of visual dysfunction by testing vision and/or stereopsis. If a visual dysfunction is found, the child is sent to a specialist for a comprehensive eye examination to find the cause.

Therefore, there is a pressing need for more efficient and effective methods and apparatus for visual screening. The instrument can be attached to a smart phone and can be directly used for objectively detecting amblyopia reasons. The instrument provided by the invention has the characteristics of convenience and rapidness in operation, effectiveness, high efficiency and light weight, and is easy to carry and low in price.

Disclosure of Invention

The invention provides an eye vision instrument for objective vision general survey, which comprises: the 1-plate and several optical components, 2-light source, 3-anterior slit (frontal view as in 4), 5-principal focus, 6-positive lens, 7-beam splitter, 9-virtual image, (frontal view as in 10) will be far from its initial position 3. The light beam is diverged by the virtual image 9, turned by about 90 degrees via the thin slide 7 and projected toward both eyes 13 of the examinee. The light beam reflected by the thin slide 7 appears to be emitted by its virtual image 11 (front view as 12), and a small target, which may be of any shape, for example, a cross shape, is placed in the back slit 14 (top view as 15) outside the principal focal point 6 of the positive lens 5, so that it is rotated by 90 degrees by the thin slide 7 through its real image 16 (front view) formed by the positive lens 5 and focused on the forehead of the subject. The clear real image 16 determines the examination distance (e.g. 1 meter) between the instrument and the subject. During the examination the real image 16 is moved along the midline of the subject's eyes so that the beams will be symmetrically incident on the subject's eyes, and in order for the instrument to be attachable to a smartphone 20, a nanoplatelet 19 is mounted behind the panel 1. When the flat plate small hole 8 is aligned with the camera 18 of the smart phone, the nano sticker 19 is attached to the smart phone in a clinging mode.

Preferably, the principle of the instrument is similar to that of a conventional ophthalmoscope which is used by professional eye optometrists to test the refractive state of a subject and is reliable and accurate. From the direction of movement, speed, width and brightness of the retinal return, the examiner can assess the refractive status of the examined eye and from the clarity of the retinal return, detect the presence or absence of opacity in the refractive media of the examined eyes, which can lead to deprivation and blocking amblyopia. The video recording of the instrument will collect the same information as conventional optometry, which is sufficient for the purpose of vision screening, and in addition, the instrument has some different functions from conventional optometry.

Preferably, the apparatus can be used for binocular vision rather than monocular vision. It can collect information of both eyes of the subject and compare them. It can also detect strabismus, ametropia, and pupillary aberrations.

Preferably, the result recorded by the video of the instrument can be stored in a medical record file of a detected person, and the follow-up visit can be tracked for a long time.

Preferably, the video recording results of the apparatus are digitized, and can be conveniently sent to professional analysis, or can be objectively analyzed by a computer program, rather than being subjectively judged by the examiner.

Preferably, the apparatus is not provided with equipment such as a phoropter, a trial frame and a trial lens or a row of spectacles in front of the eyes of the subject, and the equipment arranged in front of the eyes can make the infant not easy to accept the examination.

Preferably, the instrument uses a longer examination distance without frightening or distracting the infant, whereas the shorter examination distance of the conventional optometry is limited by the length of the examiner's arm in the range of 0.5 to 0.67 meters.

Preferably, the present instrumental examination may be performed by non-professional persons, such as parents, school nurses, kindergarten teachers, family doctors or pediatricians, and other technicians.

Preferably, the analysis of the ocular abnormality by the present apparatus can be performed by a non-professional person who has been trained or learned for a short period of time, it can be performed immediately or later by a professional team, the examination of the apparatus can be performed in a short time, it can be easily performed on infants including babies and even newborns because of their short attention and poor fitting, a small visual target is placed in front of the apparatus to stimulate the adjustment of the examinee, the dynamic binocular vision examination can be performed using the apparatus, and the accommodative ability of both eyes of the examinee can be objectively evaluated.

Preferably, the instrument has another optional detection method: the photographing is performed when the light beam just touches the pupil edge of the subject. The photograph will show the subject's corneal reflections (Hirschberg test) in both eyes, as well as the difference in retinal reflections (Bruckner test) in both eyes and the shadows inside the pupil (decentered photography optometry). The range of a common optometric is determined by the distance between the light source and the camera. Since this distance for the optometric is fixed, the measurement range for the refractive state is also limited. However, the distance of the instrument will change as the slide rotates, so it can detect a range of all refractive states.

The invention provides an eye vision instrument for objective vision general survey, which has the advantages that: the invention relates to an instrument which can be conveniently attached to a smart phone or a similar camera device. The instrument adopts the working principle of a conventional retinoscope, and the retinoscope examination method is an objective method which is routinely used by eye vision professionals and can accurately measure the refractive state of a patient. However, such conventional microscope examination can examine only both eyes separately, and the present instrument can examine both eyes of the subject at the same time. Therefore, the instrument can easily detect the refractive state of the examinee and detect the refractive error and strabismus. The results of conventional optometry are subjectively determined by the examiner, while the instrument is recorded in digital video and can be analyzed by a short-learning non-professional, or sent to a professional consultant, or analyzed by a computer program. Conventional optometry is limited by the length of the examiner's arm, typically at a distance of 0.5 to 0.67 meters from the examinee, while the apparatus can be performed at any distance so that children can easily accept the examination. The conventional optometry is a time-consuming examination, but can be performed in a short time using the instrument, especially for young children including infants and even newborns, because of their short time of attention and low fitness, and because the instrument can be easily used by non-professionals, it can be widely used for visual screening.

Drawings

Fig. 1 is a side view of an objective vision popularization instrument attachable to a smartphone.

Fig. 2 is a front view of an objective vision popularization instrument attachable to a smartphone.

Fig. 3 is a rear view of an objective vision popularization instrument attachable to a smartphone.

Detailed Description

An eye vision instrument for objective vision general survey has a slit in front of light source or filament as narrow band light source.

An eye vision instrument for objective vision general investigation features that its internal band light source can be a virtual image formed by positive lens or concave mirror with central peephole.

A virtual image formed by a slit or a filament can be rotated by about 90 degrees by a thin glass sheet, a plane mirror or a concave mirror with a peephole in the center, and then the light beam is projected to the two eyes of a person to be detected.

In use, as shown in figure 2, the thin slide 7 is able to rotate about a horizontal axis 20, the horizontal axis 20 passing through the thin slide 7 and being perpendicular to the examination optical path which is the line connecting the midpoint of the subject's eyes to the camera 18 and which passes through the plate orifice 8. As the thin slide 7 rotates upward or downward as shown in fig. 1, the light beam 21 projected on the face of the subject will also move upward or downward. When the light beam 21 is incident on the pupil of the subject, it illuminates a part of the retina of the subject and is reflected back to exit through the pupil, and the exiting light beam forms an external image on the far point plane through the optical system of the eyeball. Such a reflection seen in the pupil of the subject is called a retinal return. As the thin slide 7 rotates up or down, the illuminated spot on the retina will also move up or down, so that its external image will also move up or down.

As the external image moves past the camera 18, the smartphone will capture and record the retinal return. If the external image is located behind the camera 18, the moving direction of the retinal reflection will be consistent with the moving direction of the light beam entering the pupil of the subject, which is called "clockwise movement", and if the external image is located in front of the camera 18, the moving direction of the retinal reflection will be opposite to the moving direction of the light beam entering the pupil of the subject, which is called "counterclockwise movement", and meanwhile, the oblique movement of the binocular retinal reflection, the outward rotation of the left/right eyes, the opposite moving direction of the binocular retinal reflection, the turbidity of the left/right eye dioptric medium, the drooping of the upper eyelid of the left/right eyes, and the unequal size of the pupil of the two eyes can be detected.

The examination should be performed in a dimly lit but not completely dark environment so that the young child to be examined is not afraid while their pupils can remain large. The examiner needs to guide the examinee to watch the far sighting mark, and holds the instrument close to the examinee's gaze and 1 m away from the examinee. The light source 2 is turned on, and an image 16 of a small target is clearly projected on the forehead of the subject. And opening the video recording function of the smart phone, and rotating the thin glass sheet up and down for 7 times. The above process is repeated at the vertical, horizontal, 45 degree and 135 degree meridian positions, respectively. If the direction of movement, width, velocity, and intensity of the retinal return vary between these meridian positions, this may indicate astigmatism and/or refractive error in the eyes of the subject.

The inspection result can be immediately seen from the smartphone screen during the inspection process, or can be analyzed later.

During the examination process, a ruler or a small printed matter can be placed on the forehead of the examinee, so that the camera of the smart phone can be focused better. The ruler can also be used for measuring the interpupillary distance of eyes, the width of a reflecting strip and the movement speed of a detected person.

High refractive errors, especially hyperopia, astigmatism, refractive error, strabismus or opacities in the eye will result in amblyopia. This is the purpose of visual screening.

The above embodiments are only for the purpose of illustrating the present invention in detail, and are not to be construed as limiting the invention, and other persons in the art may make any changes and substitutions to the technical solution of the present invention without inventive efforts, and all fall within the protection scope of the present invention.

Claims

1. An eye vision instrument for objective vision screening, characterized by the structure: a flat plate (1) and a plurality of optical components, the optical components comprise a light source (2), a front slit (3), a main focus, a positive lens (6), a spectroscope (7) and a virtual image (9), the light beam is diverged by the virtual image (9), rotates by about 90 degrees through a thin glass sheet (7) and is projected to two eyes (13) of a person to be examined, the light beam reflected by the thin glass sheet (7) appears to be emitted by the virtual image (11) thereof, a small target is arranged in a rear slit (14) and is positioned at the outer side of the main focus (6) of the positive lens (5), so that a real image (16) formed by the positive lens (5) is focused on the forehead of the person to be examined after being rotated by 90 degrees through the thin glass sheet (7), a clear real image (16) determines the examination distance between the instrument and the person to be examined, the real image (16) moves along the midline of the two eyes of the person to be examined during the examination, so that the light beam can be symmetrically incident on the two eyes of the person to be examined, in order to enable the instrument to be attached to a smart phone (20), a nano sticker (19) is mounted on the back of the tablet (1), and when the tablet small hole (8) is aligned with a smart phone camera (18), the nano sticker (19) is attached to the smart phone in a clinging mode.

2. The eye vision apparatus for objective vision screening as claimed in claim 1, wherein a slit is provided in front of the light source or the filament is used as a narrow band light source.

3. The eye-vision apparatus for objective visual screening as claimed in claim 2, wherein said internal strip light source can be a virtual image by a positive lens or a concave mirror with a peephole at the center.

4. The eye-vision apparatus for objective visual screening as claimed in claim 1, wherein the virtual image of the slit or filament can be rotated by about 90 degrees by the glass slide, the central mirror with the peephole or the concave mirror, which should be a front surface mirror, to avoid the interference caused by the ghost image due to the reflection of the back surface, and then the light beam is projected to both eyes of the subject.

5. The eye vision apparatus for objective vision screening as recited in claim 1, wherein dynamic screening is performed to assess the accommodative ability of the subject.

6. The eye vision apparatus for objective vision screening as claimed in claim 1, which can be used to test the refractive state and accommodative ability of animals.