GB2367903A

GB2367903A - Releasably adhered filter for lens

Info

Publication number: GB2367903A
Application number: GB0024481A
Authority: GB
Inventors: Jacqueline Donnelly
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-10-05
Filing date: 2000-10-05
Publication date: 2002-04-17
Also published as: GB0024481D0

Abstract

A filter 4 for a lens 5 is arranged to be releasably adhered to the surface of the lens. The filter may be a plastic film, may be a self cling film and may comprise an adhesive. The film may be tinted and may be used in conjunction with spectacles 3 to convert normal spectacles into sunglasses. The filter may include a hologram.

Description

FILTER

The present invention relates to a filter for a lens.

The health and safety benefits in wearing sunglasses to reduce the intensity of light, particularly UV (ultraviolet) radiation, reaching the wearer's eyes are well known. For the large number of people who wear prescription glasses, however, this means buying a second pair of prescription glasses with tinted lenses, using conventional clip-on sun filters

on their prescription glasses or wearing a pair of ordinary sunglasses over their prescription glasses. Prescription sunglasses can be expensive and thus the cost of prescription sunglasses can be difficult to justify especially considering that the sunglasses may only be used occasionally. Clip-on sun filters and wearing two pairs of sunglasses can be unsightly and inconvenient.

The present invention has been made in consideration of these problems.

According to an aspect of the present invention there is provided a filter for a lens arranged to be adhered to the surface of the lens.

According to another aspect of the present invention there is provided a lens having a filter adhered to a surface thereof.

The invention provides for provision of low cost filters which may be discretely affixed to lenses and which have particular application in converting ordinary prescription glasses into sunglasses.

The filter is preferably arranged to be releasably adhered to the surface of a lens, thus enabling temporary conversion of prescription glasses into sunglasses.

The filter preferably comprises a plastic film, for example a vinyl film.

A suitable film is sold as Sun Shade Vinyl by DIY Plastics (UK) Ltd, Regal Way, Faringdon, Oxfordshire, SN7 7XD, England. The film is preferably a self-cling film. Such films can releasably adhere to surfaces through static attraction, due to the build up of static electrical charges. Alternatively, however, a side of the film could be coated with a suitable adhesive, especially a releasable adhesive. Any adhesive is preferably optically clear.

The filter is preferably tinted and may be tinted with a variety of different colours. The filter is preferably operative to reduce or eliminate transmission of UV radiation. Both of the aforementioned properties are desirable attributes of lenses for sunglasses.

The filter may include some form of indicia, for example letters, numerals and logos, which indicia may comprise advertising material. The filter may include a hologram.

In one embodiment two filters are supplied together in a pack. The two filters are respectively shaped to substantially cover a surface of each of the two lenses of a pair of spectacles. The pack may comprise a backing or release paper to which the filters may be releasably adhered.

Filters according to the invention are economic to produce,

sufficiently so that they may be regarded as disposable. In use with spectacles they do not substantially change the appearance of the spectacles as they can be produced from film which is relatively thin compared to the typical thickness of spectacle tenses. By using filters with a different colour tint it is possible to change the appearance of spectacles.

Filters according to the invention are a good deal less cumbersome than conventional clip-on sunshades for spectacles.

In one embodiment the characteristics of the filter are as follows : TOTAL SOLAR ENERGY REJECTION 55.3% TOTAL SOLAR ENERGY TRANSMISSION 44.6% TOTAL UV REJECTION 97. 5% TOTAL UV TRANSMISSION 2.4% VISIBLE LIGHT TRANSMISSION 38.0% SHADING COEFFICIENT (i. e. the amount of shading) 0.58% R-FACTOR 1.75% U-FACTOR (heat loss) 0.57% In order that the invention may be more clearly understood an embodiment thereof will now be described by way of example with reference to the accompanying drawings of which: Figure 1 shows two filters according to the invention; and Figure 2 shows a pair of spectacles with a filter applied to one lens thereof and a filter partially applied to the other lens thereof.

Referring to Figure 1, two filters 1 are shown releasably adhered to a release paper 2. Each filter comprises self-cling vinyl film. The film is optically clear, tinted, and has UV filtering properties. Thus, it is possible to see clearly through the film 1 but the intensity and UV radiation content of light passing through the film is reduced as it passes through the film 1.

The self-cling properties of the film 1 give the film 1 a tendency to adhere to other articles. The two filters 1 on the release paper 2 correspond in shape to the exposed surface of the lenses of a pair of spectacles. As they are arranged on the release paper 2 the two filters are mirror images of each other. The filters 1 are shown cross-hatched rather than shaded for clarity of reproduction.

Referring now to Figure 2, this figure shows a pair of spectacles 3 with filters 4 of the type illustrated in Figure 1 adhered to the lenses thereof. The normally exposed surface of the right hand lens of the spectacles is substantially completely covered by a filter 4. The normally exposed surface 5 of the left hand lens is shown partially covered by a filter 4, the filter being partially peeled back from the surface of the lens as it may be during its application or removal from the lens.

The filters 4 are releasably adhered to the lenses of the spectacles 3 converting the spectacles into sunglasses. When the need for sunglasses is over the filters may be removed and either retained for later re-use or discarded. The filters are considerably cheaper to produce than conventional clip-on sunshades allowing them to be economically disposed of and allowing a user to buy a number of different types of filters for use with a single pair of spectacles. For example, filters of different colour tint and intensity of tint or filtering properties may be provided.

The above embodiment is described by way of example only, many variations are possible without departing from the invention.

Claims

1. A filter for a lens arranged to be releasably adhered to the surface of the lens.

2. A filter according to claim 1 arranged to be releasably adhered to the surface of the lens.

3. A filter according to either claim 1 or 2 comprising a plastic film.

4. A filter according to claim 3, wherein the film is a self-cling film.

5. A filter according to any of claims 1 to 3 comprising an adhesive.

6. A filter according to any preceding claim wherein the filter is tinted.

7. A filter according to any preceding claim operative to reduce or eliminate transmission of UV radiation.

8. A filter according to any preceding claim including some form of indicia.

9. A filter according to any preceding claim including a hologram.

10. A pack comprising two filters according to any preceding claim respectively shaped to substantially cover a surface of each of the two lenses of a pair of spectacles.

11. A lens with a filter according to any preceding claim adhered to a surface thereof.

12. A filter substantially as herein described with reference to the accompanying drawings.

12. A pair of spectacles with a filter according to any preceding claim adhered to a surface of each lens thereof.