GB2119537A - Lighting unit - Google Patents

Abstract

A lighting unit which comprises a source of light 16, a reflector 20 and a collimator 22 including an adjustable shutter 28 whereby the cross sectional shape of the beam can be adjusted. The adjustable shutter can also comprise a template corresponding in outline to an object to be illuminated. The adjustable shutter enables an object, for example a picture, to be illuminated precisely leaving the surrounding areas in darkness so as to produce a very striking effect. <IMAGE>

Description

SPECIFICATION Lighting unit This invention relates to a lighting unit, in particular to a lighting unit capable of giving a precisely defined field of illumination.

In having aesthetically pieasing interior design and decoration in homes, offices, hotels and the like lighting plays an important part. It is quite common to highlight a particular feature within a room, for example a special ornament or a painting, by directing light at it. Hitherto, means of directing light in this manner have been relatively crude and the article to be highlighted merely falls within a generalised pool of illumination.

The invention seeks to provide a lighting unit which is capable of providing a precise pool of illumination to highlight only a desired area.

According to the present invention there is provided a lighting unit which comprises a source of light, a reflector, and a collimator for producing a coherent beam, the collimator including an adjustable shutter whereby the cross-sectional shape of the beam can be adjusted.

Preferably, the adjustable shutter comprises two or more slides mounted at right-angles to one another to enable a beam of the desired crosssection and size to be produced.

The lighting unit of the invention will generally be placed in a concealed position so that the light source itself is not readily visible and the beam emanating therefrom will precisely illuminate a desired object, for example a painting. However the unit may be so finished as to be aesthetically pleasing to the eye enabling it to be mounted on portable slide rails for temporary use, e.g. at art exhibitions, or under ceilings with no roof void, or with very high roofs. The effect produced is quite different from merely directing a generalised light source towards the object since, with the unit of the invention, the object in question, for example a painting, is brightly illuminated whereas the frame and surrounding area is not illuminated at all. Therefore the object stands out in an extremely prominent manner.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a sectional plan view of a unit constructed in accordance with the invention; Figure 2 is an elevational view of the shutter mechanism; and Figure 3 is a view of a unit mounted for use.

Referring to the drawings, the unit generally designated 10 comprises a body portion 12 containing a lamp holder 14 and an electric lamp 1 6 and in the case illustrated the electric lamp 1 6 is a 1 2V bulb and may be a quartz halogen bulb similar to those used in car headlights.

Accordingly, a transformer 1 8 is provided to enable the unit to operate off a normal domestic mains electricity supply. Behind the lamp 1 6 there is a reflector 20 to direct light towards a collimator 22 having lenses 24 and 26 therein.

Within the collimator 22 there is provided a shutter unit 28 (illustrated in Figure 2) which comprises two pairs of slides 30, 32, 34, 36 mounted at right-angles to one another. Each pair 30, 32 and 34, 36 is adjustable to enable the respective slides to move towards and away from one another thereby altering the size and shape of the central aperture 38.

The unit 10 may be mounted on a suitable universal mounting 40 to enable it to be directed as desired. In Figure 3 the unit is illustrated mounted on a ceiling joist 42 in the space between a ceiling 44 and a roof or upper floor 46.

A suitable hole is cut in the ceiling 44 to enable the beam generated by the unit 10 to pass therethrough.

In use, the device 10 is positioned as illustrated in Figure 3 and directed at, for example, a painting. The collimator 22 is focused and the slides 30, 32, 34, 36 within the shutter arrangement 28 are adjusted so that the field of illumination precisely coincides with the object being illuminated. The effect of the device is that the object, the painting, appears to be illuminated from within since the source of light is hidden and the field of illumination is so precise.

Naturally variations on the above may be provided within the scope of the invention. The slides within the shutter arrangement 28 may be of other shape enabling pools of illumination other than square or rectangular to be produced.

For specific end uses a template corresponding in outline to an object, for example a vase, may be inserted in the shutter unit so that the object may be precisely illuminated.

Claims (Filed on 1 1/a/83) 1. A lighting unit which comprises a source of light, a reflector, and a collimator for producing a coherent beam, the collimator including an adjustable shutter whereby the cross sectional shape of the beam can be adjusted.

2. The unit as claimed in claim 1 in which the adjustable shutter comprises two or more slides mounted at right angles to one another to enable a beam of the desired cross section and size to be produced.

3. The unit as claimed in either of claims 1 or 2 in which the adjustable shutter comprises two pairs of slides mounted at right angles to one another each pair being adjustable to enable the respective slides to move towards and away from one another thereby altering the size and shape of the central aperture defined by the pairs of slides.

4. A lighting unit substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

5. An illumination arrangement comprising a lighting unit as claimed in any one of claims 1 to 4 and an illuminated picture or other object in which the adjustable shutter is adjusted so as to illuminate the object precisely and not illuminate the surroundings of the object.

6. An arrangement as claimed in claim 5 in

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Lighting unit This invention relates to a lighting unit, in particular to a lighting unit capable of giving a precisely defined field of illumination. In having aesthetically pieasing interior design and decoration in homes, offices, hotels and the like lighting plays an important part. It is quite common to highlight a particular feature within a room, for example a special ornament or a painting, by directing light at it. Hitherto, means of directing light in this manner have been relatively crude and the article to be highlighted merely falls within a generalised pool of illumination. The invention seeks to provide a lighting unit which is capable of providing a precise pool of illumination to highlight only a desired area. According to the present invention there is provided a lighting unit which comprises a source of light, a reflector, and a collimator for producing a coherent beam, the collimator including an adjustable shutter whereby the cross-sectional shape of the beam can be adjusted. Preferably, the adjustable shutter comprises two or more slides mounted at right-angles to one another to enable a beam of the desired crosssection and size to be produced. The lighting unit of the invention will generally be placed in a concealed position so that the light source itself is not readily visible and the beam emanating therefrom will precisely illuminate a desired object, for example a painting. However the unit may be so finished as to be aesthetically pleasing to the eye enabling it to be mounted on portable slide rails for temporary use, e.g. at art exhibitions, or under ceilings with no roof void, or with very high roofs. The effect produced is quite different from merely directing a generalised light source towards the object since, with the unit of the invention, the object in question, for example a painting, is brightly illuminated whereas the frame and surrounding area is not illuminated at all. Therefore the object stands out in an extremely prominent manner. The invention will be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a sectional plan view of a unit constructed in accordance with the invention; Figure 2 is an elevational view of the shutter mechanism; and Figure 3 is a view of a unit mounted for use. Referring to the drawings, the unit generally designated 10 comprises a body portion 12 containing a lamp holder 14 and an electric lamp 1 6 and in the case illustrated the electric lamp 1 6 is a 1 2V bulb and may be a quartz halogen bulb similar to those used in car headlights. Accordingly, a transformer 1 8 is provided to enable the unit to operate off a normal domestic mains electricity supply. Behind the lamp 1 6 there is a reflector 20 to direct light towards a collimator 22 having lenses 24 and 26 therein. Within the collimator 22 there is provided a shutter unit 28 (illustrated in Figure 2) which comprises two pairs of slides 30, 32, 34, 36 mounted at right-angles to one another. Each pair 30, 32 and 34, 36 is adjustable to enable the respective slides to move towards and away from one another thereby altering the size and shape of the central aperture 38. The unit 10 may be mounted on a suitable universal mounting 40 to enable it to be directed as desired. In Figure 3 the unit is illustrated mounted on a ceiling joist 42 in the space between a ceiling 44 and a roof or upper floor 46. A suitable hole is cut in the ceiling 44 to enable the beam generated by the unit 10 to pass therethrough. In use, the device 10 is positioned as illustrated in Figure 3 and directed at, for example, a painting. The collimator 22 is focused and the slides 30, 32, 34, 36 within the shutter arrangement 28 are adjusted so that the field of illumination precisely coincides with the object being illuminated. The effect of the device is that the object, the painting, appears to be illuminated from within since the source of light is hidden and the field of illumination is so precise. Naturally variations on the above may be provided within the scope of the invention. The slides within the shutter arrangement 28 may be of other shape enabling pools of illumination other than square or rectangular to be produced. For specific end uses a template corresponding in outline to an object, for example a vase, may be inserted in the shutter unit so that the object may be precisely illuminated. Claims (Filed on 1 1/a/83)

1. A lighting unit which comprises a source of light, a reflector, and a collimator for producing a coherent beam, the collimator including an adjustable shutter whereby the cross sectional shape of the beam can be adjusted.

2. The unit as claimed in claim 1 in which the adjustable shutter comprises two or more slides mounted at right angles to one another to enable a beam of the desired cross section and size to be produced.

3. The unit as claimed in either of claims 1 or 2 in which the adjustable shutter comprises two pairs of slides mounted at right angles to one another each pair being adjustable to enable the respective slides to move towards and away from one another thereby altering the size and shape of the central aperture defined by the pairs of slides.

4. A lighting unit substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

5. An illumination arrangement comprising a lighting unit as claimed in any one of claims 1 to 4 and an illuminated picture or other object in which the adjustable shutter is adjusted so as to illuminate the object precisely and not illuminate the surroundings of the object.

6. An arrangement as claimed in claim 5 in which the adjustable shutter comprises a template corresponding exactly with the shape of the article to be illuminated inserted in the collimator of the lighting unit.