GB2337101A

GB2337101A - Illumination device

Info

Publication number: GB2337101A
Application number: GB9809987A
Authority: GB
Inventors: Pietro Palladino
Original assignee: NEWTECH PATENT Ltd
Current assignee: NEWTECH PATENT Ltd
Priority date: 1998-05-08
Filing date: 1998-05-08
Publication date: 1999-11-10
Also published as: GB9809987D0

Abstract

According to the present invention there is provided an illumination device having an aperture 20 for the emission of light and comprising a housing 10, a socket 30 located within the housing for receiving a light source 36, and a lens 24; wherein the lens 24 comprises a plurality of transparent rods each having a longitudinal direction and each positioned within the aperture 20 such that emitted light passes through the rods transversely of the longitudinal direction thereof. The device provides a very wide light distribution in the longitudinal plane (for example above 2 # radians) and a very narrow light distribution of the transverse plane (4-5 degrees). The illumination device thus provides a "light blade" which is particularly suitable for "skim lighting" (for example for illuminating the sides of a building) while reducing the extraneous luminous flux pollution to a minimum.

Description

2337101 1 ILLUMNATION DEVICE The present invention relates to an

illumination device such as a flood light suitable for illuminating the external facade of a building at night.

According to the present invention there is provided an illumination device having an aperture for the emission of light and comprising a housing, a socket located within the housing for receiving a light source, and a lens; wherein the lens comprises a plurality of transparent rods each having a longitudinal direction and each positioned within the aperture such that emitted light passes through the rods transversely of the longitudinal direction.

An embodiment of the invention will now be described by way of example only and with reference to the accompanying drawings in which: - Figure 1 is a cross-sectional view of an illumination device according to one embodiment of the present invention, Figure 2 is a different cross-sectional view of the device illustrated in Figure 1, Figure 3A is a plan view of the lens of the device shown in Figure 1 and Figure 3B is a cross-sectional view taken on the line A-A of Figure 3A, Figure 4 is a plan view of the device shown in Figure 1, and Figure 5 is a cross-sectional view of the separate power supply unit used in association with the lamp housing of Figure 1.

As shown in Figures 1, 2 and 4, the illumination device comprises a housing 10 having a hollow, rectangular central portion 12 closed at each end by a respective end plate 14, 16. Preferably, resilient seals 18 are provided between the central portion 12 and the end plates 14, 16. The seals 18 assist in protecting the 2 inside of the illumination device against undesirable atmospheric influences, particularly the ingress of moisture.

End plate 16 has a central aperture 20, through which light is emitted. The aperture 20 is sealed by a face plate 22 and a lens 24. The lens 24 comprises a plurality of transparent cylindrical rods. Face plate 22 is preferably formed of a ceramic glass and the cylindrical rods forming the lens 24 are preferably formed of Pyrex. The rods of the lens 24 may be held in contact with the face plate 22 by the assistance of a backing plate 26. Backing plate 26 can conveniently be formed of a ceramic glass.

As will be readily appreciated from Figures 1 and 2, the cylindrical rods of the lens 24 each has a longitudinal direction which spans the aperture 20. That is, light is emitted from the device by passing transversely through the rods of the lens. As illustrated, the longitudinal length of the rods spans the shorter distance of the rectangular aperture 20.

Fixed within the housing 10 is a reflector 28. The reflector 28 is preferably a separate component having a reflective surface comprising a superpurity aluminium (99.9 %) vacuum cladding. Reflector 28 preferably has a shape which is defined by two crossing parabolas.

Also within the housing 20 is a light source socket 30 which is secured to a carriage 32. Carriage 32 slides within the central portion 12 of the housing 10. A threaded adjustor 34 connects the carriage 32 to the end plate 14. This arrangement provides for precise positioning of the socket 30 with respect to the reflector 28 and the lens 24. Operatively a bulb 36 is located in the socket 30. Bulb 36 is preferably a metal halide bulb, for example having a rating of 35 W or 70 W.

It will be appreciated that the preferred form of light source bulb generates a significant amount of heat. Consequently, the central portion of the housing may preferably be formed from an aluminium extruded bar, with the end plates 14 and 3 16 also being formed of aluminium. Further, the housing 10 is provided with external cooling fins 38, as best seen in Figure 4.

The electrical supply to the socket 30 is provided by a conventional style grommet fixing 40, thus enabling the moisture resistant sealing of the housing to be maintained. As is well known, despite the fact that metal halide bulbs can be powered by a conventional 240 V supply, certain power supply circuitry is required. In order to maintain such circuitry at an optimum temperature, preferably not exceeding 65 'C, such circuitry (indicated by reference numeral 42 is Figure 5) is located within a separate housing 44. As illustrated in Figure 5, the housing 44 may have a similar construction to that of the lamp housing 10, including for example the provision of cooling fins. Of course, the end plates of housing 44 provide only for electrical connection, in contrast to the aperture and lens arrangement of plate 16 of the lamp housing 10.

Typically, the dimensions of the aperture 20 might be approximately 155 mm by 58 mm, with the height of the lamp being say 200 mm. In such a case the Pyrex glass rods of the lens 24 might have a diameter of 4 to 6 mm and the front safety glass may have a thickness of 3 to 4 mm.

Considering the rectangular shape of aperture 20, the provision of the cylindrical rods of the lens 24 result in a very wide light distribution in the longitudinal plane (for example above 27r radians) and a very narrow light distribution of the transverse plane (43 degrees). The illumination device thus provides a "light blade" which is particularly suitable for "skim lighting" (for example for illuminating the sides of a building) while reducing the extraneous luminous flux pollution to a minimum.

One embodiment of the invention has been described with reference to the accompanying drawings. Various modifications which do not depart from the scope of the invention as defined by the appended claims will be readily apparent to those skilled in the art.

4

Claims

1. An illumination device having an aperture for the emission of light and comprising a housing, a socket located within the housing for receiving a light source, and a lens; wherein the lens comprises a plurality of transparent rods each having a longitudinal direction and each positioned within the aperture such that emitted light passes through the rods transversely of the longitudinal direction thereof.

2. An illumination device as claimed in claim 1, wherein the rods are formed of a glass material.

3. of Pyrex.

An illumination device as claimed in claim 1, wherein the rods are formed

4. An illun-dnation device as claimed in claim 1, further comprising a separate reflector within the housing.

5. An illumination device as claimed in claim 4, wherein the reflector has a shape defined by two crossing parabolas.

6. An illumination device as claimed in claim 4 or 5, wherein the reflector has a high purity aluminium cladding.

7. An illumination device as claimed in claim 4 or 5, wherein the reflector is fixed to the housing.

8. An illumination device as claimed in claim 1, further comprising a transparent cover which closes the aperture.

9. An illumination device as claimed in claim 8, wherein the rods are positioned between the lamp source socket and the cover.

10. An illumination device as claimed in claim 8 or 9, wherein the cover is formed of a ceramic glass material.

11. An illumination device as claimed in any preceding claim, wherein the rods are cylindrical.

12. An illumination device as claimed in any preceding claim, wherein the light source socket is provided in a carriage which slides within the housing so as to provide adjustment of the socket relative to the aperture.

13. An illumination device as claimed in any preceding claim, further comprising , a power supply housing separate from the housing containing the light source socket.

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