WO2020118347A1

WO2020118347A1 - Vision testing apparatus

Info

Publication number: WO2020118347A1
Application number: PCT/AU2019/000155
Authority: WO
Inventors: Benjamin ARMITAGE
Original assignee: Armitage Optometry Pty Ltd
Priority date: 2018-12-14
Filing date: 2019-12-16
Publication date: 2020-06-18
Also published as: AU2019396123A1; GB2594625A; GB202109067D0

Abstract

A portable vision testing apparatus for testing the visual acuity of a subject comprising: an elongate body defining an enclosed space having an eyepiece located at a proximal end and terminating at a distal end; an illumination element mounted within the body adjacent the eyepiece to illuminate the enclosed space of the elongate body; a testing element configured to be located adjacent a distal end of the body for presenting one or more images to be viewed by the subject to determine the subject's visual acuity; and an adjuster unit mounted within the body so as to be in the subject's line of sight when using the apparatus, the adjuster unit being configured to adjust the one or more images provided on the testing element such that the images are perceived by the subject to be at a predetermined distance from the subject to facilitate the test.

Description

VISION TESTING APPARATUS

RELATED APPLICATIONS

The present application claims priority from Australian provisional patent application no. 2018904755 filed on 14 December 2018, the entire contents of which are incorporated herein by reference.

FIELD OF INVENTION

The present invention relates generally to an apparatus for testing the visual acuity of an individual, and in particular, to an apparatus configured to be portable and easily used in a variety of situations to provide a simple and accurate reading of a person’s visual acuity.

BACKGROUND OF THE INVENTION

Vision problems are common amongst the general population for a variety of reasons, which can range from genetic defects and disease, as well as high blood pressure, advanced age or changes in eye health over time. Thus, it is common for many vision defects to be corrected through the use of spectacles or eye glasses which act to address the eye’s deficiencies such that the individual can have as close as possible to“normal vision”.

For many individuals, the presence of a vision problem or defect may go unnoticed from many years, or until the individual is tested. Such individuals may not appreciate just how bad their vision has become and may not understand the danger they place themselves and others in by doing normal tasks, such as driving a car.

For tasks such as driving, good vision plays an important role in ensuring safety for all road users. In the Australian state of Victoria, in accordance with the Optometrists Association of Australia’s Victorian division, around 47% of the population report visual disorders of some kind or another. To drive a vehicle there is a need to judge distances and identify potential hazards moving along a road, to ensure the safety of road users and pedestrians. Poor or low vision can significant impair a driver’s ability to see and react to dangerous situations, especially when driving at night and/or at high speeds.

For this reason, throughout Australia, a vision test forms part of the licence testing and registration system. Upon applying for a driver’s licence in Australia, it is necessary for individual’s to declare any illness, disability or disease which may affect their ability to safely drive a vehicle. For individuals that have vision problems and require spectacles or eyeglasses to correct such problems, it is often a condition of obtaining the licence that they only drive with their corrective glasses on, as to do so would be a safety risk to the population. Similarly, for older drivers, at ages older than 70/75, it is required that the driver undergo an eyesight test each year as part of their registration process.

Vision tests used for determining driver licence eligibility general measure the visual acuity of the individual. Such tests typically employ the Snellen Chart, or similar reading chart, which comprises a series of letters starting from larger print and ending up with fine print. The charts are designed to be read at 6 metres to 3 meters from the chart and in order to successfully pass the test, the individual must past the test through each eye being better that 6/12. Other tests may be conducted on the individual’s visual field to provide a determination of the individual’s peripheral vision. These tests may be used to test whether the user has a horizontal extent of vision of at least 110 degrees within 10 degrees above or below the horizontal midline.

Irrespective of the manner in which the vision of an individual is tested during the licence registration process, it is common for many individual’s vision to deteriorate after they have received their licence, so as to fall below an acceptable level of vision. In licence renewal situations, this deterioration of the eyes may not be picked up until such time as the individual is requested to perform an eye test. Thus it is highly possible for many licences drivers to have unacceptable visual acuity without knowing it. Similarly, for those who have obtained a driver’s licence with the presence of spectacles or eye glasses, it is a condition of their licence that, when driving, their spectacles or corrective lenses are worn. In this situation, many individuals may forget their glasses or lose their glasses and drive their vehicle without such visual assistance, resulting in a dangerous and potentially fatal situation arising, and a situation that is in contravention with the conditions of their licence.

Thus, given the large percentage of the population who have visual problems and the large number of individual’s who have conditional licenses requiring the use of corrective lenses, it is highly likely that many drivers are illegally driving their vehicles and are putting themselves and others in risk. Whilst measures have been taken to address drink driving and drug driving by testing individuals as to the presence of alcohol or drugs in their system, no such system involving testing the visual acuity of the driver to ensure that they are within the acceptable range of vision has been developed.

Hence, the present invention is directed towards addressing this deficiency of the prior art.

The above references to and descriptions of prior proposals or products are not intended to be, and are not to be construed as, statements or admissions of common general knowledge in the art. In particular, the following prior art discussion does not relate to what is commonly or well known by the person skilled in the art, but assists in the understanding of the inventive step of the present invention of which the identification of pertinent prior art proposals is but one part.

STATEMENT OF INVENTION

According to a first aspect, there is provided a portable vision testing apparatus for testing the visual acuity of a subject comprising:

an elongate body defining an enclosed space having an eyepiece located at a proximal end and terminating at a distal end;

an illumination element mounted within the body adjacent the eyepiece to illuminate the enclosed space of the elongate body;

a testing element configured to be located adjacent a distal end of the body for presenting one or more images to be viewed by the subject to determine the subject’s visual acuity; and

an adjuster unit mounted within the body so as to be in the subject’s line of sight when using the apparatus, the adjuster unit being configured to adjust the one or more images provided on the testing element such that the images are perceived by the subject to be at a predetermined distance from the subject to facilitate the test.

In one embodiment, the testing element may be controllable by a tester to control the images that are to be presented to the subject.

In one embodiment, the eyepiece is configured to abut the subject’s face and extend about the eyes of the subject to prevent external light entering the enclosed space.

The illumination element may be an LED light mounted within the eyepiece of the body to illuminate the enclosed space. The LED light may have a switch mounted on an external wall of the body adjacent the proximal end thereof. In one embodiment, the testing chart is a disc insertable into a slot formed in the body adjacent the distal end thereof. The disc may comprise a plurality of testing images, one set of which may be located in a line of sight of the subject when the disc is inserted into the slot. The images presented to the subject may be changeable by changing the orientation of the disc when it is inserted into the slot. The images may be letters.

In another embodiment, the testing chart is a barrel mounted within the enclosed space of the body adjacent the distal end thereof. The barrel may have a plurality of sets of images formed thereon at regular intervals about the periphery of the barrel which may be located within the line of sight of the subject. The barrel may be rotatable by way of a knob located outside of the body to change the set of images presented to the subject in their line of sight. The images may be letters.

In another embodiment, the testing chart may be a belt mounted between a pair of axles within the enclosed space of the body adjacent the distal end thereof. The belt may have a plurality of sets of images formed on a surface thereof which may be located within the line of sight of the subject. The belt may be movable by way of a knob located outside of the body to change the set of images presented to the subject in their line of sight. The images may be letters.

The distance extender may comprise a pair of lenses mounted adjacent the eyepiece. A focal point of each of the lenses may be selected to extend the virtual distance of the presented images from the subject to a predetermined distance based upon the test being performed.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be better understood from the following non-limiting description of preferred embodiments, in which:

Fig. 1 is a view of the apparatus of the present invention in use;

Fig. 2 is a top view of the apparatus of Fig. 1 ;

Fig. 3 is a side view of the apparatus of Fig. 1 ;

Fig. 4 is an exploded view of the apparatus of Fig. 1 ;

Fig. 5 is a perspective view of an alternative embodiment of a testing chart for use with the apparatus of Fig. 1 ;

Fig. 6A and 6B show views of yet another alternative embodiment of a testing chart for use with the apparatus of Fig. 1; and

Fig. 7 is a view of a conventional Snellen Chart for determining visual acuity in accordance with the prior art.

DETAILED DESCRIPTION OF THE DRAWINGS

Preferred features of the present invention will now be described with particular reference to the accompanying drawings. However, it is to be understood that the features illustrated in and described with reference to the drawings are not to be construed as limiting on the scope of the invention.

The present invention will be described below in relation to a particular embodiment for use by an authority for randomly testing the visual acuity of an individual driving a vehicle. However, it will be appreciated that the structure and use of the device may take a variety of different forms and still fall within the scope of the present invention.

Turning to Fig. 1 , a vision testing apparatus 10 in accordance with an embodiment of the present invention is depicted. The apparatus 10 is intended for use in testing the visual acuity of a user through presenting a chart within a handset arrangement which is presented to the individual in a manner which is capable of simply and effectively providing a determination of the visual acuity reading for that individual.

Referring to Fig. 7, a conventional Snellen Chart 100 is depicted together with the acuity results 102 assigned to an individual for reading the particular letter line 104 - 110 from a predetermined distance (typically 3 or 6 metres). In Victoria, an individual capable of reading line 108 from the assigned distance will receive a 6/12 score which is sufficient to obtain a driving licence. Thus, the apparatus 10 of Fig. 1 is configured to present either only line 108 or each of the lines 104 - 110 to the individual to obtain their visual acuity score. The manner in which that is achieved will be discussed in more detail below.

The apparatus 10 comprises an elongate body having an eyepiece 12 located at a proximal end which terminates at a closed distal end 20. The body tapers towards the distal end 20 in both a lateral and vertical manner as is shown in Fig.

1.

The eyepiece 12 is configured to be positioned over both eyes and comprises a flexible band portion 11 that is configured to contact the face of the user to position the apparatus 10 and to block light from entering the apparatus 10 when in use. The flexible band portion is preferably made from a silicone material which may be treated with a non-bacterial layer to avoid bacterial transmission between users of the apparatus 10. In this regard, the surface of the flexible band portion 11 may be provided with removal liners, which can be removed and discarded each time the apparatus is to be used.

As is shown more clearly in Figs. 2 and 4, the band portion 11 has a curved, concave surface having an upper rim portion 13 that is configured to abut the user’s forehead immediately above the user’s eyebrows. The lower rim portion 14 of the band portion 11 extends across the user’s cheeks and over the user’s nose such that the eye holes 15 are correctly located over the user’s eyes when the apparatus 10 is positioned in the manner as depicted in Fig. 1.

The eyepiece 12 has an TED 16 mounted therein to illuminate the internal portion of the apparatus 10 and is controlled by a switch 17 located on the upper surface of the eyepiece 12.

The eyepiece 12 is connected to an adaptor unit that is housed in intermediate housing 18 which houses a pair of lenses 19 which are provided for each of the eye holes 15 of the eyepiece 12. Each of the lenses 19 are retained within a mounting member 20 which secures the lenses in position. The mounting member 20 is attached to one side of the intermediate housing 18 which has a pair of holes 18a formed therein to facilitate viewing therethrough via the lenses 19.

A chamber body 21 is attached to the other side of the intermediate housing 18 which extends from the intermediate body 18 to the distal end 40. The chamber body 21 comprises two half shells 21a, 21b which are joined together to form the chamber body 21 by screws 22 in the manner as depicted in Fig. 4. In this regard, the chamber body 21 is a substantially enclosed space. A slot 23 is formed through the surface of the upper shell 21a adjacent the distal end 40. The slot 23 is configured to receive a testing element 24 for testing the visual acuity of the user.

The testing element 24 is one embodiment for presenting the chart to the user for testing. In this embodiment, the testing chart 24 is in the form of a substantially square disc having letters arranged on both surfaces thereof. The letters can be arranged around the edges of the disc such that it can be rotated to provide four chart testing options to the user. As the letters are arranged on both sides of the disc, they are offset on opposing sides such that the authority giving the test can see the actual letters that the user is seeing (see Fig. 1) to verify whether the answers given by the user are correct. Thus, the letters are arranged such that the lower group of letters provided on one side of the disc is the same as the upper group of letters provided on the other side of the disc.

The apparatus 10 of the present invention functions in a manner such that when the testing chart 24 is inserted through the slot 23, the user will view the testing chart 24 at the desired distance, due to the presence of the lenses 19. Therefore, the test is consistent with tests performed at a licensing venue or at an optometrist or eye specialist with the TED 16 providing the required illumination and the lenses 19 ensuring that the letters presented to the individual are at a correct distance from the individual. Therefore, if the letters presented on the testing chart 24 are the equivalent of the letters present in row 108 of Fig. 7 and the user fails to correctly recall the letters, the user will be considered to have failed the vision test and appropriate action may be taken to ensure that the individual’s vision is addressed before they are licensed to drive again. Such a test can be simply and effectively conducted as a routine road side test issued by a police officer and can form part of a standard drug and/or alcohol testing regime.

It will be appreciated that the manner in which the testing chart can be configured can vary between embodiments of the present invention.

Fig. 5 depicts an alternative embodiment of the present invention whereby the testing chart 50 is provided by way of a barrel 52 which may be rotated between any one of four, or more, positions by way of a knob 54 that extends outside the chamber body 21 of the apparatus.

As will be appreciated from Fig. 4, the barrel 52 may be mounted adjacent the distal end of the chamber body 21 such that it is located within the line of sight of the user. The surface of the barrel 52 has testing letters 53 located thereon which extend across the barrel 52 and are spaced apart around the periphery of the barrel 52 at 90° intervals. The knob 54 is connected to the end of the barrel by a shaft 56 so as to be located outside of the chamber body 21. This enables a testing authority using the apparatus 10 to change the letters 53 that are positioned in the line of sight of the user to vary the visual acuity test as required.

The surface of the turning knob 54 has a plurality of markings or indicia 55 formed thereon to indicate to the testing authority the particular letters 53 that are being viewed by the user undergoing the test to determine the accuracy of the test. The testing authority can then move the barrel to another set of testing letters 53 if they wish to conduct another test of the user. It will be appreciated that the barrel 52 will typically be mounted on a support (not shown) to ensure that the barrel is free to rotate under action of the testing authority between each of the determined testing positions.

Fig. 6A and 6B each depict yet another alternative embodiment of the present invention whereby the testing chart 60 is provided by way of a belt 62 which may be rotated between any one of three positions by way of a knob 64 that extends outside the chamber body 21 of the apparatus 10.

Once again, as will be appreciated from Fig. 4, the belt 62 is mounted around two vertically spaced apart axles 63 and is mounted adjacent the distal end of the chamber body 21 such that it is located within the line of sight of the user. The belt 62 has a series of holes 62a and 62b formed along opposing edges thereof which engage with a sprocket wheel (not shown) or similar spaced projections formed on the surface of the axles 63. This ensures that movement of one of the axles will cause the belt 62 and the other axle to move in a controlled manner.

The surface of the belt 62 has testing letters 61 located thereon which extend across the belt 62 and are vertically spaced apart on the front surface the belt 62, as shown. A turning knob 64 is connected to an extended end of the lower axle 63 and is located outside of the chamber body 21. This enables a testing authority using the apparatus 10 to change the letters 53 that are positioned in the line of sight of the user to vary the visual acuity test as required.

This is achieved by rotating the turning knob 64 clockwise or anticlockwise to move the belts such that one set of testing letters 61 is located within the line of sight of the user being tested. The surface of the turning knob 64 may have indicators thereon to indicate to the testing authority the number of the test being presented to the user such that the testing authority can check the visual acuity of the user. If the testing authority seeks to change the test, they can simply rotate the turning knob 64 such that the next set of testing letters 61 is presented to the user.

As is shown in Fig. 6B, to assist the testing authority in identifying the test being conducted so as to identify the letters 61 being read out by the user, the rear of the belt 62 may have numbers 65 provided thereon which identify the specific letters 61 being presented to the user’s line of sight. Thus, the chamber body 21 may have a window or recess (not shown) formed therein to enable the testing authority to view the highlighted number 65 to identify the test being undertaken.

It will be appreciated that, irrespective of which type of testing chart system is employed, the apparatus of the present invention provides a simple and effective means for testing the visual acuity of an individual in any situation, especially in a vehicle or at a roadside. The apparatus 10 may include a hook to attach to a belt or the like of a testing authority for storage when not in use, or may be simply stowed away and used when desired.

The lenses are able to provide a simple means for locating the testing letters at the desired distance from the user to undergo the test. The results are able to be determined immediately as the user provides the results. This enables a user to be simply and effectively tested in relation to their visual acuity and should the user fail the test, the user may be prevented from any further driving until such time as their eyesight is corrected through the use of corrective lenses and the like.

Through the provision of such an apparatus as the present invention, police officers and other law enforcement are able to quickly and effectively test drivers for their visual acuity in much the same way as drivers are able to be alcohol and drug tested, to ensure that driver safety is optimised and that drivers who hold conditional licenses are adhering to those conditions.

Throughout the specification and claims the word“comprise” and its derivatives are intended to have an inclusive rather than exclusive meaning unless the contrary is expressly stated or the context requires otherwise. That is, the word “comprise” and its derivatives will be taken to indicate the inclusion of not only the listed components, steps or features that it directly references, but also other components, steps or features not specifically listed, unless the contrary is expressly stated or the context requires otherwise.

It will be appreciated by those skilled in the art that many modifications and variations may be made to the methods of the invention described herein without departing from the spirit and scope of the invention.

Claims

The Claims defining the invention are as follows:

1. A portable vision testing apparatus for testing the visual acuity of a subject comprising:

2. A portable vision testing apparatus according to claim 1 , wherein the testing element is controllable by a tester to control the images that are to be presented to the subject.

3. A portable vision testing apparatus according to claim 1, wherein the eyepiece is configured to abut the subject’s face and extend about the eyes of the subject to prevent external light entering the enclosed space.

4. A portable vision testing apparatus according to claim 1, wherein the illumination element is an LED light mounted within the eyepiece of the body to illuminate the enclosed space.

5. A portable vision testing apparatus according to claim 4, wherein the LED light has a switch for controlling the state of the LED light, the switch being mounted on an external wall of the body adjacent the proximal end thereof.

6. A portable vision testing apparatus according to claim 1 , wherein the testing element is a chart provided on a disc that is insertable into a slot formed in the body adjacent the distal end thereof.

7. A portable vision testing apparatus according to claim 6, wherein the disc comprises a plurality of testing images, one set of which are located in a line of sight of the subject when the disc is inserted into the slot.

8. A portable vision testing apparatus according to claim 7, wherein the images presented to the subject are changeable by changing the orientation of the disc when it is inserted into the slot.

9. A portable vision testing apparatus according to claim 7, wherein the images are letters.

10. A portable vision testing apparatus according to claim 1, wherein the testing element is a barrel mounted within the enclosed space of the body adjacent the distal end thereof.

11. A portable vision testing apparatus according to claim 10, wherein the barrel has a plurality of sets of images formed thereon at regular intervals about the periphery of the barrel which are located within the line of sight of the subject.

12. A portable vision testing apparatus according to claim 10, wherein the barrel is rotatable by way of a knob located outside of the body to change the set of images presented to the subject in their line of sight.

13. A portable vision testing apparatus according to claim 12, wherein the images are letters.

14. A portable vision testing apparatus according to claim 1, wherein the testing element is a belt mounted between a pair of axles within the enclosed space of the body adjacent the distal end thereof.

15. A portable vision testing apparatus according to claim 9, wherein the belt has a plurality of sets of images formed on a surface thereof which are located within the line of sight of the subject.

16. A portable vision testing apparatus according to claim 14, wherein the belt is movable by way of a knob located outside of the body to change the set of images presented to the subject in their line of sight.

17. A portable vision testing apparatus according to claim 16, wherein the images are letters.

18. A portable vision testing apparatus according to claim 1, wherein the adjuster unit comprises a pair of lenses mounted adjacent the eyepiece.

19. A portable vision testing apparatus according to claim 18, wherein a focal point of each of the lenses is selected to extend the virtual distance of the presented images present on the testing element from the subject to a predetermined distance suitable for conducting the test.

20. A portable vision testing apparatus according to claim 18, wherein the adjuster unit is removable from the body to be replaced as required.