GB2113373A - A device for producing lighting effects - Google Patents

Abstract

A device for producing lighting effects comprises a point-shaped light source arranged in a hollow body (6) having at least one opening (3) with an extremely small diameter or width. With this device there is produced a parallel beam of light which due to dispersion in the surrounding air is readily visible. <IMAGE>

Description

SPECIFICATION A device for producing lighting effects This invention relates to a device for producing lighting effects having a light source which is partly shielded by a shade.

This type of device is known. In such a device, the coherent, parallel beam of light from a laser source strikes a rotatably mounted, driven ball, the surface of which is covered, in the manner of a mosaic, with a plurality of small, flat mirrors. Thus there are obtained a plurality of beams of light going in different directions, depending on the orientation of the mirrors, and, due to the rotation of the ball, these various beams move about constantly in the surroundings. In smoky air, such as is met especially in dance halls, the reflected light, focussed into parallel beams, produces bright dispersed light due to scattering by the dust particles in the air and this dispersed light is readily visible against its surroundings from relatively large distances due to the correspondingly darker illumination of the surroundings. Thus very impressive effects are achieved.

The disadvantage of the known device, however, is to be found in the high purchase price, especially of the laser source.

According to the present invention there is provided a device for producing lighting effects which device comprises a point-shaped light source arranged in a hollow body having at least one opening, wherein the distance between the light source and the opening is selected relative to the size of the light source such that in use in at least one direction a beam of light which is substantially parallel emerges through the opening.

According to the invention, an essentially parallel, non-divergent beam of light is produced using a small conventional light source of great brightness, such as a high pressure xenon lamp, a mercury discharge lamp or a halogen lamp, an extremely small opening in the shade and a large distance between the light source and the opening relative to the size of the light source and the opening. In this way, virtually the same stimulating effect is produced as in the case of the known device in a fairly simple manner, i.e. without a laser source and without optical means such as lenses, mirrors or prisms. Furthermore, many kinds of variations and thus many different kinds of effects can be achieved with relatively simple means and accordingly less expensively than with the known device.

In the following, the invention shall be described by way of example with reference to the accompanying drawings wherein: Figure 1 is a schematic representation of a device according to the invention, and Figures 2 and 3 are schematic representations of two different embodiments of a device according to the invention.

As shown in Fig. 1, a point-shaped light source 1, e.g. a high pressure xenon lamp with a focal surface of 2 X 0.8 mm, is arranged at the centre of a cylindrical or spherical hollow body 2, having, for example, a diameter of 30 cm. Hollow body 2 is blackened on the inside. It is made, for example, of aluminium plate. In the hollow body 2 there is provided a circular opening 3, for example 1 mm in diameter or width. The distance between light source 1 and opening 3 is thus many times greater than the length of the filament of light source 1 or the diameter or width of opening 3. The arrangement is thus comparable with a pin-hole camera, and it is clear that an almost parallel beam of light 4 therefore will emerge from circular opening 3 and appear as a bright beam due to dispersion over dust particles in surrounding air 5.

The embodiment of device shown in Fig. 2 comprises a hollow ball 6 connected by a shaft 7 to a driving arrangement 9 mounted on ceiling 8 which driving arrangement 9 sets hollow body 6 in rotation. Hollow body 6 is provided over its surface with a plurality of extremely small openings 3, so that rays 4 extend from hollow body 6 into surrounding air 5 in the shape of a porcupine.

In the embodiment of device shown in Fig.

3, a hemispherical bowl 10 mounted on ceiling 8 has as its opening a circular slot 11 around the surface of the ball. Thus a conical beam 12 is produced.

A further embodiment which is not shown consists in providing a circular opening in the hollow body and having the light beam emerging through the opening hit a rotatably mounted mirror which is rotated by an appro priate drive arrangement. If the rotational speed is high enough, the human eye can no longer perceive the separate beams, so that essentially the same light effect is achieved, i.e. a conical beam, as in the case of the embodiment according to Fig. 3.

It is also possible to provide a hollow body or partial sphere with a series of circular openings of different diameter arranged in parallel planes, which openings may be opened and closed alternately. Thus the coni cal beam may be made to diverge and converge, the opening and closing of the open ings being controlled, for example, by a so called "lighting console".

Numerous variations of lighting effects can, of course, be achieved when several devices according to the invention are used in one room.

In one embodiment, the diameter of the sphere was 30 cm and the sphere was made of blackened aluminium plate. The area of the point-shaped light source, in this case a high pressure xenon lamp, was 0.8 X 2 mm. The diameter of the opening was 8 mm.

Claims (10)

1. A device for producing lighting effects which device comprises a point-shaped light source arranged in a hollow body having at least one opening, wherein the distance between the light source and the opening is selected relative to the size of the light source such that in use in at least one direction a beam of light which is substantially parallel emerges through the opening.

2. A device according to claim 1, wherein the point-shaped light source is formed by a low voltage lamp having a short filament.

3. A device according to claim 2, wherein the low voltage lamp is a high pressure xenon lamp, a mercury discharge lamp or a halogen lamp.

4. A device according to any of claims 1 to 3, wherein the hollow body is formed by a hollow sphere, a partial sphere, a cylindrical tube or a semi-cylindrical shell and the light source is arranged at the centre of the sphere or cylinder.

5. A device according to any of the preceding claims, wherein the opening is circular or slot-shaped.

6. A device according to any of claims 1 to 3, wherein the hollow body comprises a rotatably mounted hollow sphere connected to a drive mechanism, or comprises a partial sphere, and has a plurality of circular openings.

7. A device according to any of claims 1 to 3, wherein the hollow body comprises a stationary hollow sphere or partial sphere and has as an opening at least one circular slot around the spherical hollow body.

8. A device according to claim 7, which has a series of circular slot openings of different diameter in planes parallel to each other, at least one such opening being closable.

9. A device according to any of claims 1 to 4, which comprises a circular opening in the hollow body and wherein the light beam emerging through the opening hits a rotatably mounted mirror which is connected to a drive mechanism.

10. A device according to claim 1 substantially as described with reference to and as illustrated in the accompanying drawings.