Lighting system for a data display device including a light guide

• US 8,517,589 B2
• Filed: 06/01/2011
• Issued: 08/27/2013
• Est. Priority Date: 06/03/2010
• Status: Active Grant

• Current Assignee: The Swatch Group Research And Development Ltd
• Original Assignee: The Swatch Group Research And Development Ltd
• Inventors: Tortora, Pierpasquale
• Primary Examiner(s): Alavi, Ali
• Application Number:
  US13/151,052
• Publication Number:
  US 20110299300A1
• Time in Patent Office: 818 Days
• Field of Search: 362/551, 362/555, 362/560, 362/559, 362/97.1, 362/97.3, 362/615, 362/621, 362/623
• US Class Current: 362/615
• CPC Class Codes: G02B 6/002 by shaping at least a portion of the light guide, e.g. with collimating, focussing or diverging surfaces
• CPC Class Codes: G02B 6/0028 Light guide, e.g. taper
• CPC Class Codes: G02B 6/0076 Stacked arrangements of multiple light guides of the same or different cross-sectional area

Abstract

Lighting system for a data display device (12, 20), wherein said lighting system includes a light guide (1; 22) including an area (2; 26) into which the light produced by at least one light source (4) is injected, said injection area (2; 26) is extended by an area (8; 24) for extracting the light propagating inside the guide (1; 22) to light the display device (12; 20), said extraction area (12, 20) is provided with light extractors (10), the light guide (1; 22) takes the form of a loop closed on itself at the light injection area (2; 26) to allow the light originating from the light source (4) and which was not extracted from the light guide (1; 22) in the extraction area (8; 24) to continue to travel inside the light guide (1; 22) and to return to the starting point thereof at the light injection area (2; 26), the data display device (12; 20) is arranged inside the loop, and the lighting system is characterized in that the light is extracted from the light guide (1; 22) in a perpendicular direction to a plane (P1) defined by the direction (X-X) of injection of light into the guide (1), and by a generating line (Y-Y) of the loop.

Claims

1. A lighting system for a data display device, the lighting system comprising:

(a) a data display device; and

(b) a light guide, wherein the light guide includes

(i) an injection area, wherein a light produced by at least one light source is injected into the injection area of the light guide;

(ii) an extraction area, wherein the extraction area is an extended area of the injection area, wherein the extraction area is disposed to extract the light propagating inside the light guide to light the display device, and

wherein the extraction area has light extractors,

wherein the light extractors are disposed to

(1) direct the extracted light towards a data display surface of the data display device when the data display device is of the reflective type and the data display surface is turned towards the extraction area;

or

(2) direct the extracted light towards a rear surface of the data display device opposed to a data display surface when the data display device is of the transmissive type and the rear surface of the data display device is turned towards the extraction area,

wherein the light guide takes the form of a closed loop, wherein the loop is closed at the light injection area to allow the light originating from the light source that was not extracted from the light guide in the extraction area to continue to travel inside the light guide and to return to the starting point thereof at the light injection area,

wherein the light guide is dimensioned so the data display device can be arranged inside the loop, and

wherein the light is extracted from the light guide along a perpendicular direction to a plane defined by the direction of injection of light into the guide, and by a generatrix line of the loop.

2. The lighting system according to claim 1, wherein the light injection area is extended by the extraction area via a first semi-cylindrical transmission area, wherein the extraction area is extended in turn by a second semi-cylindrical transmission area that is connected to the injection area, and

wherein the data display device is of the reflective type with the data display surface oriented towards the light extraction area of the light guide.

3. The lighting system according to claim 1, wherein the light extraction area is arranged in an extension of the light injection area and is extended by a first semi-cylindrical transmission portion that is in turn extended by a second flat transmission portion, wherein the second flat transmission portion is closed on the light injection area via a third semi-cylindrical transmission portion, wherein the first, second and third transmission portions are disposed to return the light that has not been used in the extraction area to the injection area for re-injection into the light guide, and

wherein the data display device being of the transmissive type with the data display surface thereof oriented towards the flat transmission portion.

4. A lighting system for a data display device, the lighting system comprising:

(a) a data display device; and

(b) a light guide, wherein the light guide includes

(i) an injection area, wherein the light produced by at least one light source is injected into the injection area of the light guide;

(ii) an extraction area, wherein the extraction area is an extended area of the injection area, wherein the extraction area is disposed to extract the light propagating inside the light guide to light the display device, and wherein the extraction area has light extractors,

wherein the light guide takes the form of a closed loop, wherein the loop is closed at the light injection area to allow the light originating from the light source that was not extracted from the light guide in the extraction area to continue to travel inside the light guide and to return to the starting point thereof at the light injection area,

wherein the data display device is arranged inside the loop, wherein the data display device is of the reflective type with the data display surface oriented towards the extraction area of the light guide,

wherein the light is extracted from the light guide along a perpendicular direction to a plane defined by the direction of injection of light into the guide, and by a generatrix line of the loop,

wherein the injection area is extended via a first semi-cylindrical transmission area, wherein the extraction area is extended in turn by a second semi-cylindrical transmission area that is connected to the injection area, and

wherein the first semi-cylindrical transmission portion and the second semi-cylindrical transmission portion are connected to the light injection area by two, substantially triangular connector sections.

5. A lighting system for a data display device, the lighting system comprising:

(a) a data display device; and

(b) a light guide, wherein the light guide includes

(i) an injection area, wherein the light produced by at least one light source is injected into the injection area of the light guide;

(ii) an extraction area, wherein the extraction area is an extended area of the injection area, wherein the extraction area is disposed to extract the light propagating inside the light guide to light the display device, and wherein the extraction area has light extractors,

wherein the light guide takes the form of a closed loop, wherein the loop is closed at the light injection area to allow the light originating from the light source that was not extracted from the light guide in the extraction area to continue to travel inside the light guide and to return to the starting point thereof at the light injection area,

wherein the data display device is arranged inside the loop,

wherein the light is extracted from the light guide along a perpendicular direction to a plane defined by the direction of injection of light into the guide, and by a generatrix line of the loop,

wherein the light extraction area is arranged in an extension of the light injection area and is extended by a first semi-cylindrical transmission portion that is in turn extended by a second flat transmission portion, wherein the second flat transmission portion is closed on the light injection area via a third semi-cylindrical transmission portion,

wherein the first, second and third transmission portions are disposed to return the light that has not been used in the extraction area to the injection area for re-injection into the light guide,

wherein the data display device being of the transmissive type with the data display surface thereof oriented towards the flat transmission portion, and

wherein the second flat transmission portion and the third semi-cylindrical transmission portion are connected to the light injection area by two, substantially triangular connector sections.

6. A lighting system for a data display device, the lighting system comprising:

(a) a data display device; and

(b) a light guide, wherein the light guide includes

(i) an injection area, wherein a light produced by at least one light source is injected into the injection area of the light guide;

(ii) an extraction area, wherein the extraction area is an extended area of the injection area, wherein the extraction area is disposed to extract the light propagating inside the light guide to light the display device, and wherein the extraction area has light extractors,

wherein the light guide takes the form of a closed loop, wherein the loop is closed at the light injection area to allow the light originating from the light source that was not extracted from the light guide in the extraction area to continue to travel inside the light guide and to return to the starting point thereof at the light injection area,

wherein the data display device is arranged inside the loop,

wherein the light is extracted from the light guide along a perpendicular direction to a plane defined by the direction of injection of light into the guide, and by a generatrix line of the loop, and

wherein the light guide is symmetrical relative to a longitudinal median plane.

7. A lighting system for a data display device, the lighting system comprising:

(a) a data display device; and

(b) a light guide, wherein the light guide includes

(i) an injection area, wherein a light produced by at least one light source is injected into the injection area of the light guide;

(ii) an extraction area, wherein the extraction area is an extended area of the injection area, wherein the extraction area is disposed to extract the light propagating inside the light guide to light the display device, and wherein the extraction area has light extractors,

wherein the light guide takes the form of a closed loop, wherein the loop is closed at the light injection area to allow the light originating from the light source that was not extracted from the light guide in the extraction area to continue to travel inside the light guide and to return to the starting point thereof at the light injection area,

wherein the data display device is arranged inside the loop, and

wherein the light is extracted from the light guide along a perpendicular direction to a plane defined by the direction of injection of light into the guide, and by a generatrix line of the loop, and

wherein the injection area has a parabolic profile.