GB2168168A - Optical aid for viewing one's own eye - Google Patents

Abstract

An optical aid to assist viewing of one's own eye, such as when inserting a contact lens, has a tube 10 closed at one end by a plate 14 provided with a reflecting coating on its inner face. At the other end of the tube is mounted a lens 12 of positive power (for instance of about + 10 diopters), snapped into a groove in the tube. On looking into the tube through the lens, a viewer will observe an enlarged image of his own eye. This aid may also be an eye bath. Tube 15 also acts as a contact lens holder. The reflecting surface may be on the lens itself (Fig. 3 not shown). <IMAGE>

Description

SPECIFICATION Optical aid This invention relates to an optical aid, suitable for example for enabling a user to look into or at his own eye.

Not infrequently, a person may wish to look into or at his own eye. In the case of a wearer of contact lenses, that person may well wish to look at each of his own eyes, whenever he inserts or removes a lens. Conventionally, use is made of a relatively small "handbag" mirror, which is usually a plain mirror, when inspecting one's eyes or inserting contact lenses. There are however available relatively small concave mirrors giving a degree of magnification and which can usefully be employed, though such mirrors are primarily intended for use when applying cosmetics, and so often are incorporated in a container or case for cosmetic preparations.

Such mirrors as have been described above, though relatively small, nevertheless may range in size from about 50 mm diameter or square, up to perhaps 100 mm by 75 mm.

Such mirrors are therefore relatively bulky, and if carried about one's person so as to be ready for immediate use, are prone to breakage unless incoporated within a rigid case, such as a cosmetic container-but in the latter case the mirror then becomes even more bulky. Such mirrors are therefore not entirely convenient, especially for men who wear contact lenses but who do not normally carry handbags or cosmetic containers.

It is a pricipal aim of this invention to provide an optical aid which is suitable for use when inspecting one's own eye, which aid may be constructed so as to be relatively small and compact so that it may easily be carried about one's person.

Accordingly, this invention provides an optical aid comprising a tube closed at one end by a lens of positive power, and a reflecting surface disposed within the tube or at or adjacent the other end of the tube which reflecting surface is optically associated with the lens, and arranged so that a user looking closely at the lens will see an enlarged image of his own eye.

In a relatively simple embodiment of this invention, the tube is closed at one end by the lens of positive power and the reflecting surface is disposed ar the other end of the tube so as to close that other end; the aid is then used by holding the tube relatively closely to the eye which is to be inspected, and by looking along the axis of the tube (which should be substantially coincident with the optical axis of the lens) an enlarged image of the eye may be seen. The degree of enlargement will of course depend upon the power of the lens employed, but it is preferred for there to be a magnification lying typically within the range of from 5 to 10 times.

Though the tube of the just-described embodiment may be either cylindrical or to some extent conical, to suit the optical characteristics of the lens, the utility of the optical aid may be enhanced by shaping the tube so as to have a form similar to a conventional eye bath. Then, either the reflecting surface or the lens-as appropriate-may be mounted on a carrier which may be releasably attached to one end of the tube, whereby removal of the carrier enables the aid to be at least partially filled with liquid, and employed as an eye bath. When it is desired once more to look into the eye, the carrier should be replaced, and the aid used as described above.

An alternative embodiment of this invention is arranged as a container, for example for carrying contact lenses. In this alternative embodiment, the tube should be essentially cylindrical, and should be provided with a dividing wall mid-way therealong. Each end of the tube should be provided with a removable cap, one of which caps serves as a carrier for the lens.

Depending upon the optical characteristics of the lens, either the dividing wall itself may be arranged to provide the reflecting surface which co-operates with the lens, when the appropriate cap is fitted to the tube, or the dividing wall may be made completely transparent and the other cap then serving as a carrier for the reflecting suface, such that both caps have properly to be fitted to the tube, in order to enable the aid to be employed for inspecting an eye. As is usually the case with conventional contact lens holders, the caps should effect a liquid-tight seal to the tube, for instance by being screw- threaded to engage with similar screw threads on the tube with an appropriate seal member provided therebetween, so that the tube may partially be filled with liquid to maintain the contact lenses moist, whenever located therewithin.

In either of the above-described two embodiments of this invention, the lens may be a simple lens of positive power or may be a compound lens, having two or more lens elements cemented together or maintained spaced apart, as appropriate to give the required optical characteristics. One possibility for such a compound lens is to provide a plano-concave lens element cemented directly to a bi-convex lens element, the planar surface of the first element being rendered reflective, so that there is no need then to provide a separate reflecting surface, remote from the lens itself. Such a compound lens may be incorporated for example in the base of a tube shaped like an eye bath or may be disposed to provide the end wall of a cap for a contact lens holder.

By way of example only, three specific embodiments of this invention will now be described in greater detail, reference being made to the accompanying drawings, in which: Figure 1 is a cross-sectional view through a first embodiment of this invention; Figure 2 is a cross-sectional view through a second embodiment, formed as a contact lens carrier; and Figure 3 shows an alternative form of lens suitable for use in the embodiments of either Figs. 1 or 2.

Referring initially to Fig. 1, it can be seen that the optical aid there illustrated comprises a tube 10 of circular cross-section but of tapering diameter such that the tube has a slight conical shape. The tube could be formed of metal, but preferably is moulded from a plastics material. At the broader end 11 of the tube there is provided an internal groove into which is snapped a bi-convex lens 12 of positive power. If required, that lens may appropriately be cemented into place, for example by means of a bead of cement applied internally of the tube around the edge of the lens.

At the other, narrower end 13 of the tube 10, there is provided a planar plate 14 provided with a reflective coating on its internal surface. This plate 14 may be formed integrally with the tube 10, especially in the case of a plastics material moulding.

The optical characteristics of the lens 12 and the length of the tube 10 are selected so that the overall optical aid has a magnifying power of about 8 times. The lens 12 itself typically has a diameter of about 20 to 35 mm but advantageously has a diameter of 30 mm and has power of +10 diopters. For such an arrangement, the separation of the lens and the reflecting surface should be about 15 mm.

For a case where the tube is moulded of a plastics material, an optically clear plastics material such as an acrylic-based polymer may be employed; the lens may then be moulded in one piece with the tube. The reflecting surface would then separately be formed and be suitably attached to the tube, for example by being cemented thereto.

In an alternative arrangement, the tube 10 is formed to have an irregular shape, closely similar to that employed for a conventional eye bath. The plate 14 may then be made removable, whereby the aid may be employed as an eye bath, when the plate 14 is removed, but may be used to inspect an eye, when the plate 14 is fitted to the tube.

Referring now to Fig. 2, there is shown a contact lens holder arranged in accordance with this invention, and comprising a cylindrical tube 15 divided centrally by a radial wall 16. Each end of the tube 15 is externally screw-threaded, and may receive a cap 17 or 18, each of which caps has a cylindrical flange internally screw-threaded for engage ment with the threads on the tube 15. If required, a sealing member such as an O-ring (not shown) may be provided within each cap, at the junction between the cylindrical flange and the end wall thereof, to effect a seal with the end of the tube.

Cap 17 serves as a holder for a bi-convex lens 19 of positive power, the lens being held in place for example by being snapped into a groove provided in the cylindrical flange 20 of the cap 17, the lens 19 then constituting the end wall of the cap. As with the embodiment of Fig. 1, the lens may be cemented in place, when fitted to the cap.

Depending upon the optical characteristics of the lens 19 and the dimensions of the tube 15, either the dividing wall 16 may be provided with a reflective coating on its surface directed towards the cap 17 holding the lens 19, or that wall 16 may be made transparent, and the internal surface of the end wall 21 of cap 18 may be made reflective, for co-operation with the lens 19. Either way, a user would look at the lens 19 from the direction A marked on Fig. 2 and would then see an enlargement image of his own eye. The holder may however be used to contain contact lenses, one to each side of the wall 16, and if required the holder may at least partially be filled with an appropriate liquid or solution, as is the case with conventional contact lens holder.

Referring to Fig. 3, there is shown an alternative lens and reflecting surface arrangement, to replace those described above with reference to Figs. 1 and 2. Here, the lens is constructed by cementing together a bi-convex lens element and plano-concave lens element 26, the planar surface of which is coated with a reflecting material so as to provide a reflective surface for the lens. As illustrated in Fig.

3, this compound lens is mounted within an internally screw-threaded cap, so as to be usable with a contact lens holder as illustrated for example in Fig. 2, but of course in that case, there is no need for a separate reflective surface to be provided, either on the dividing wall 16 or on the cap 18.

Claims (10)

1. An optical aid comprising a tube closed at one end by a lens of positive power, and a reflecting surface disposed within the tube or at or adjacent the other end of the tube which reflecting surface is optically associated with the lens and arranged so that a user looking closing at the lens will see an enlarged image of his own eye.

2. An optical aid according to claim 1, wherein the tube is closed at one end by the lens of positive power and the reflecting surface is disposed at the other end of the tube so as to close that other end.

3. An optical aid according to claim 1 or claim 2, wherein the lens and reflecting sur face combination provide a magnification lying within the range of from 5 to 10 times.

4. An optical aid according to any of the preceding claims, wherein the tube is of circu lar cross-sectional shape with a diameter which reduces from said one end whereat the lens is mounted to said other end whereat the reflecting surface is mounted.

5. An optical aid according to any of the preceding claims, wherein the tube has a form corresponding to a conventional eye bath and one of the lens and the reflecting surface is removably mounted on the larger end of the tube, to permit use of the optical aid as an eye bath.

6. An optical aid according to claim 1, wherein the tube is essentially cylindrical, and is provided with a dividing wall substantially mid-way therealong, there being being two removable caps one for each of the tube respectively and one of which caps serves as a carrier for the lens.

7. An optical aid according to claims 6, wherein the dividing wall has a reflecting coating on one or both sides thereof to serve as the reflecting surface.

8. An optical aid according to claim 6, wherein the dividing wall is transparent and the other cap services as a carrier for the reflecting surface.

9. An optical aid according to any of claims 6 to 8, wherein each of said caps is screw-threaded and is interengageable with similar screw threads formed on the tube, an appropriate seal member being provided therebetween, so that each of said caps may effect a liquid tight seal to be tube.

10. An optical aid substantially as hereinbefore described with reference to and as illustrated in Fig. 1 or Figs. 2 and 3 of the accompanying drawings.