GB2240616A - An illumination enhancing device - Google Patents

Abstract

The invention relates to an illumination enhancing device and has particular application to vehicle, road traffic and the like illumination devices which may be "washed out" by sunlight. The device comprises a lens defining a first region, 6, which transmits direct sunlight incident thereon to a reflector, 2, behind the lens, and a second region, 10, which reflects direct sunlight incident thereon but allows light reflected by the reflector and light from an illuminating source, 16, between the reflector and the lens to pass therethrough. <IMAGE>

Description

"AN ILLUMINATING ENHANCItTG DEVICE" The present invention relates to an illumination enhancing device and particularly but not exclusively to a device for enhancing the illumination of rear lights, brake lights and flashing indicators of vehicles.

A disadvantage of conventional rear lights, brakelights and flashing indicators is that if sunlight is shining directly on the lens of the light, there is a serious possibility that when the light bulb is on, its effect will be "washed-out" by the sunlight thereby reducing or even nullifying its effect. This can have dangerous consequences for a following driver who, because of sunlight shining on the lens, is unable to tell, for example, whether or not a brake light or a flashing indicator is being operated.

It is an object of the present invention to reduce this danger and to that end there is provided an illumination enhancing device comprising a lens member and a reflector behind the lens member, the lens member having a first region capable of transmitting sunlight incident on the front face of the lens member onto the reflector and having a second region capable of transmitting sunlight reflected from the reflector and incident on the rear face of the lens and reflecting sunlight incident on the front face of the lens.

The first region may comprise a border region around the second region.

The device may comprise a light source, the light source being so positioned and the reflector being of such configuration that light from the light source is transmitted through the lens.

The second region may comprise material capable of absorbing sunlight incident on the front face of the lens when the light source is inoperative and releasing the absorbed sunlight when the light is activated.

The first region may be capable of transmitting incident on the front face, but not sunlight incident on the rear face of the lens.

The present invention will now be described by way of example and with reference to the accompanying drawing, the single figure of which shows a sectional view of an illumination enhancing device embodying the present invention.

Referring to the drawing there is shown a curved rear reflector 2 on the front of which is mounted a glass or plastics lens 4 which may be, for example, circular or rectangular. The lens 4 comprises an outer border region 6 through which incident sunlight depicted by single arrows 8 is capable of being transmitted. Within the outer border region 6 of the lens 4 is an inner central region 10 which is capable of transmitting the sunlight reflected from the reflector 2 through the central region 6. The front of the central region 10 is provided with a coating 12 which is capable of reflecting sunlight indicated by double arrows 14 incident on the coating 12.

Spaced from the reflector 2 is a light source in the form of an electric bulb 16. When the bulb 16 is activated, the light emanating from the bulb 16 is transmitted through the central region 10 of the lens 4 as depicted by the triple arrows 18. Part of the light is transmitted directly through the central region 10 and part of the light is initially reflected by the reflector 2.

The central region 10 having the reflecting coating 12 enables the light emanating from the bulb 16 to be enhanced by the sunlight which has been reflected by the reflector 2 thereby providing a more intense light than would be so in the case of light from the bulb 16 only.

Instead of the device comprising a central region 10 provided with a reflective coating 12 other means may be provided for enabling incident sunlight to be reflected from the central region 10 and light from the bulb 16 to be transmitted through the central region 10. For example when the bulb 16 is operating a chemical change, caused by an electric current or thermal effect, may take place in the central region 10 or special lines or facets may be provided on or in the central region 10. Alternatively, the central region may polarise light incident on its surface. Another means could be the provision of solar or phosphorescent cells.

Further means could be the use of photochromatic effects.

Still further fibre optics can be provided in the device to direct the light path.

Although the invention has been described in respect of a rear light for a vehicle, the invention is equally applicable to for example traffic lights or illuminated control panels.

Claims (11)

1. An illumination enhancing device comprising a lens member and a reflector member behind said lens member, said lens member comprising a first region arranged to allow direct sunlight incident thereon to pass therethrough onto the said reflector and a second region arranged to reflect direct sunlight incident on its front face whilst allowing light incident on its rear face to pass therethrough.

2. An illumination enhancing device as claimed in claim 1 in which said first region is arranged to reflect light incident on its rear face.

3. An illumination enhancing device as claimed in claim 1 or 2, in which said first region surrounds said second region.

4. An illumination enhancing device as claimed in claim 1, 2 or 3, in which a light source is located between the said second region of the lens and the said reflector.

5. An illumination enhancing device as claimed in claim 1, 2, 3 or 4, in which said reflector is of such configuration as to reflect light incident thereon onto the rear face of the said second region.

6. An illumination enhancing device as claimed in any preceding claim in which the front face of said second region is coated with a reflective coating.

7. An illumination enhancing device as claimed in any one of claims 1 to 5 inclusive, in which a coating on said second region is arranged to undergo a chemical change to cause said second region to reflect direct sunlight when an electric current is applied to the said coating and/or or said coating is heated.

8. An illumination enhancing device as claimed in any one of claims 1 to 5 inclusive, in which the front surface of the said second region has facets formed thereon to reflect direct sunlight and to prevent direct sunlight from passing through said second region.

9. An illumination enhancing device as claimed in any one of claims 1 to 5 inclusive, in which said second region is arranged to polarise direct sunlight incident thereon.

10. An illumination enhancing device as claimed in any preceding claim in which a dark, light-absorbent region surrounds the lens.

11. An illumination enhancing device, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.