Illumination module
An illumination module comprises a semiconductor light source and a light guide, which comprises a solid body with essentially parallel entry and exit faces and side faces extending between the entry and exit faces; and wherein the entry face receives light emitted by the semiconductor light source; the exit face is offset from the entry face and the area of the exit face exceeds the area of the entry face; a first side face comprises a uniform plane subtending an angle of inclination to the entry face; a second side face, opposite to the first side face, comprises a plurality of offset sub-faces, each sub-face subtends an angle of inclination relative to the entry face; and the inclined faces are formed so that the direction of light leaving the exit face is essentially the same as the direction of light entering the entry face.
1. A light guide comprising:
a solid body comprising:
an entry face,
an exit face parallel to the entry face, the exit face having an area that exceeds an area of the entry face,
a first inclined side face extending from the entry face to the exit face and comprising a uniform plane subtending a first angle of inclination to the entry face, and
a second inclined side face extending from the entry face to the exit face and comprising a plurality of offset sub-faces, each of the plurality of offset sub-faces subtending a second angle of inclination relative to the entry face.
2. The light guide of claim 1 , wherein the solid body is shaped such that a perpendicular extending from the entry face does not pass through the exit face, and a direction of light leaving the exit face is essentially the same as the direction of light entering the entry face.
3. The light guide according to claim 1 , wherein the area of the exit face exceeds the area of the entry face by at least 500%.
4. The light guide according to claim 1 , wherein the area of the exit face exceeds the area of the entry face by at least 1000%.
5. The light guide according to claim 1 , wherein the first angle of inclination is chosen to redirect a light ray toward the second inclined side face.
6. The light guide according to claim 1 , wherein the plurality of offset sub-faces comprises at least 5 sub-faces.
7. The light guide according to claim 1 , wherein the plurality of offset sub-faces comprises at least 10 sub-faces.
8. The light guide according to claim 1 , wherein the second angle of inclination is arranged to redirect a light ray out through the exit face.
9. The light guide according to claim 1 , wherein the second angle of inclination is the same for each of the plurality of offset sub-faces.
10. The light guide according to claim 1 , wherein the first angle of inclination is the same as the second angle of inclination.
11. The light guide according to claim 1 , wherein the first angle of inclination and the second angle of inclination are each between 45° and 60°.
12. The light guide according to claim 1 , wherein the entry face and the exit face are rectangular in shape.
13. An illumination system comprising:
a semiconductor light source; and
a light guide comprising a solid body that comprises:
an entry face adjacent the semiconductor light source,
an exit face parallel to the entry face, the exit face having an area that exceeds an area of the entry face,
a first inclined side face extending from the entry face to the exit face and comprising a uniform plane subtending a first angle of inclination to the entry face, and
a second inclined side face extending from the entry face to the exit face and comprising a plurality of offset sub-faces, each of the plurality of offset sub-faces subtending a second angle of inclination relative to the entry face.
14. The illumination system according to claim 13 , wherein the light guide is arranged such that the entry face receives essentially all light originating from the semiconductor light source.
15. The illumination system according to claim 13 , wherein the area of the exit face exceeds the area of the entry face by at least 500%.
16. The illumination system according to claim 13 , wherein the first angle of inclination and the second angle of inclination are each between 45° and 60°.
17. The illumination system according to claim 13 , wherein the semiconductor light source comprises at least one vertical-cavity surface-emitting laser (VCSEL).
18. An imaging system comprising:
a camera; and
an illumination module, the illumination module comprising:
a semiconductor light source, and
a light guide comprising a solid body that comprises:
an entry face adjacent the semiconductor light source,
an exit face parallel to the entry face, the exit face having an area that exceeds an area of the entry face,
a first inclined side face extending from the entry face to the exit face and comprising a uniform plane subtending a first angle of inclination to the entry face, and
a second inclined side face extending from the entry face to the exit face and comprising a plurality of offset sub-faces, each of the plurality of offset sub-faces subtending a second angle of inclination relative to the entry face.
19. The imaging system according to claim 18 , wherein the first angle of inclination and the second angle of inclination are each between 45° and 60°.
20. The imaging system according to claim 18 , wherein the semiconductor light source comprises at least one vertical-cavity surface-emitting laser (VCSEL).