Illumination unit and a method for point illumination of a medium

• US 6,529,265 B1
• Filed: 10/12/1999
• Issued: 03/04/2003
• Est. Priority Date: 04/14/1997
• Status: Expired due to Term

• Current Assignee: 3D Systems, Inc. (3D Systems Corporation)
• Original Assignee: Dicon A/S
• Inventors: Henningsen, Henning
• Primary Examiner(s): Adams, Russell
• Assistant Examiner(s): Brown, Khaled
• Application Number:
  US09/402,754
• Time in Patent Office: 1,239 Days
• Field of Search: 355/34, 355/35, 355/67, 355/71, 355/77, 355/53, 250/492.2
• US Class Current: 355/71
• CPC Class Codes: B41J 2/451 Special optical means therefor, e.g. lenses, mirrors, focusing means
• CPC Class Codes: B41J 2/465 using masks, e.g. light-switching masks
• CPC Class Codes: G02B 6/0008 the light being emitted at the end of the fibre

Abstract

The invention is an illumination unit for point illumination of a medium where at least one light emitter is arranged to illuminate at least one illumination face via a first lens arrangement and a microshutter arrangement. The lens arrangement has at least one microlens arranged with respect to each microshutter so that light emitted from the light emitter is focused on or in the vicinity of the optical axis of the light channel of the individual microshutters. The fed coherent light from the light emitters is modulated by the microshutters onto the illumination face.

Claims

1. An illumination unit for point illumination of a medium comprising at least one light emitter arranged to illuminate at least one illumination face via a microshutter arrangement, said microshutter arrangement comprising a plurality of microshutters, each microshutter comprising a light channel and an electrically activatable diaphragm device (4) associated with it, characterized in that at least one of the light emitters (1) is arranged to illuminate at least two microshutters via a first lens arrangement (2;

23), said lens arrangement comprising at least one microlens arranged with respect to each microshutter so that the light emitted by the light emitter or emitters is focused on or in the vicinity of the optical axis of the light channel (6;

26) of the individual microshutters.

3. An illumination unit according to claim 1, characterized in that at least one of the light emitters is formed by an optical light guide (13;

29) which is optically connected to at least one light source.

4. An illumination unit according to claim 3, characterized in that the optical light guide(s) is(are) formed by optical fibres.

5. An illumination unit according to claim 1, characterized in that at least one of the light sources (10) is formed by a short arc lamp.

6. An illumination unit according to claim 1, characterized in that the light source comprises a short arc lamp (10) having light receiving optical light guides or fibres (13) which are arranged within an angle of +/−

75°

with respect to the equator axis (E) of the lamp on a ball face (11, 12) around the lamp, and which are optically connected to and conduct light to the light emitters.

7. An illumination unit according to claim 1, characterized in that at least one of the light sources is formed by a laser source (21).

9. An illumination unit according to claim 1, characterized in that it comprises at least one light emitter in the form of a light guide (29) optically connected to a light source and arranged to illuminate a plurality of microshutters arranged in a given face shape, at least one collimation lens (22) being arranged between the light emitter and the face shape so that collimated light is conducted toward the first microlens arrangement (2;

23) associated with the microshutters.

12. An illumination unit according to claim 9, characterized in that the individual microshutters with associated microlens optics are positioned in rows in the transverse direction of the face shape with the microshutters at a given mutual distance, said rows being mutually offset in the transverse direction.

13. An illumination unit according to claim 9, characterized in that the rows are arranged such that the projection of all the individual microshutters on the transverse direction in the face shape results in a plurality of illumination points at a mutual distance in the transverse direction.

15. An illumination unit according to claim 1, characterized in that the face shape or shapes of the microshutters are arranged on one or more illumination heads (40), such that each illumination head (40) and the illumination face perform a mutual relative movement, said device being also provided with a control unit for controlling the microshutters in dependence on the relative movement between the illumination head and the illumination face (41).

2. An illumination unit for point illumination of a medium comprising at least one light emitter arranged to illuminate at least one illumination face via a microshutter arrangement, said microshutter arrangement comprising a plurality of microshutters, each microshutter comprising a light channel and an electrically activatable diaphragm device (4) associated with it, characterized in that at least one of the light emitters (1) is arranged to illuminate at least two microshutters via a first lens arrangement (2;

23), said lens arrangement comprising at least one microlens with respect to each microshutter so that the light emitted by the light emitter or emitters is focused on or in the vicinity of the optical axis of the light channel (6;

26) of the individual microshutters and said illumination unit further including a second microlens arrangement (27) arranged between the microshutters and the illumination face, so that light transmitted through the light channel (6;

26) of the individual microshutter is suitably focused on the illumination face (9;

28).

8. An illumination unit for point illumination of a medium comprising at least light emitter arranged to illuminate at least one illumination face via a microshutter arrangement, said microshutter arrangement comprising a plurality of microshutters, each microshutter comprising a light channel and an electrically activatable diaphragm device (4) where the diaphragm device is formed by plates which are pivotally hinged to the microshutter arrangement, at least one of the light emitters (1) is arranged to illuminate at least two microshutters via a first lens arrangement (2;

23), said lens arrangement comprising at least one microlens with respect to each microshutter so that the light emitted by the light emitter or emitters is focused on or in the vicinity of the optical axis of the light channel (6;

26) of the individual microshutters.

10. An illumination unit for point illumination of a medium comprising at least one light emitter in the form of a light guide (29) optically connected to a light source and arranged to illuminate at least one illumination face via a microshutter arrangement, said microshutter arrangement comprising a plurality of microshutters arranged in a face shape forming a hexagon, each microshutter comprising a light channel and an electrically activatable diaphragm device (4) associated with it, characterized in that at least one of the light emitters (1) via a first lens arrangement (2;

23) is arranged to illuminate the plurality of microshutters, said lens arrangement comprising at least one microlens with respect to each microshutter so that the light emitted by the light emitter or emitters is focused on or in the vicinity of the optical axis of the light channel (6;

26) of the individual microshutters and said illumination unit including at least one collimation lens (22) being arranged between the light emitter and the face shape so that collimated light is conducted toward the first microlens arrangement (2;

23) associated with the microshutters.

11. An illumination unit for point illumination of a medium, the illumination unit comprises at least eight hexagons (81;

87) which are illuminated by an optical fiber optically connected to an illumination source;

at least one light emitter in the form of a light guide (29) optically connected to a light source and arranged to illuminate at least one illumination face via a microshutter arrangement, said microshutter arrangement comprising a plurality of microshutters arranged in a face shape, each microshutter comprising a light channel and an electrically activatable diaphragm device (4) associated with it, characterized in that at least one of the light emitters (1) via a first lens arrangement (2;

23) is arranged to illuminate the plurality of microshutters, said lens arrangement comprising at least one microlens with respect to each microshutter so that the light emitted by the light emitter or emitters is focused on or in the vicinity of the optical axis of the light channel (6;

26) of the individual microshutters and said illumination unit including at least one collimation lens (22) being arranged between the light emitter and the face shape so that collimated light is conducted toward the first microlens arrangement (2;

23) associated with the microshutters.

14. An illumination unit for point illumination of a medium comprising at least one light emitter arranged to illuminate at least one illumination face via a microshutter arrangement, said microshutter arrangement comprising a plurality of microshutters, each microshutter comprising a light channel and an electrically activatable diaphragm device (4) associated with it, characterized in that at least one of the light emitters (1) is arranged to illuminate at least two microshutters via a first lens arrangement (2;

23) formed wholly or partly by hexagonal focal lenses, said lens arrangement comprising at least one microlens with respect to each microshutter so that the light emitted by the light emitter or emitters is focused on or in the vicinity of the optical axis of the light channel (6;

26) of the individual microshutters and said illumination unit further including a second microlens arrangement (27) formed wholly or partly by hexagonal focal lenses said second lens arrangement arranged between the microshutters and the illumination face, so that light transmitted through the light channel (6;

26) of the individual microshutter is suitably focused on the illumination face (9;

28).

16. An illumination unit for point illumination of a medium comprising at least one light emitter arranged to illuminate at least one illumination face via a microshutter arrangement, said microshutter arrangement comprising a plurality of microshutters arranged in a shape on one or more illumination heads (40) where each illumination head is formed by a rod (30), the relative movement between the illumination face (41) and the rod (30) being a single progressing movement in the transverse direction of the rod (30), each microshutter comprising a light channel and an electrically activatable diaphragm device (4) associated with it, characterized in that at least one of the light emitters (1) is arranged to illuminate at least two microshutters via a first lens arrangement (2;

23), said lens arrangement comprising at least one microlens with respect to each microshutter so that the light emitted by the light emitter or emitters is focused on or in the vicinity of the optical axis of the light channel (6;

26) of the individual microshutters.

17. An illumination unit for point illumination of a medium comprising at least one light emitter arranged to illuminate at least one illumination face via a microshutter arrangement, said microshutter arrangement comprising a plurality of microshutters, each microshutter comprising a light channel wherein said each microshutter is formed by an oscillating diaphragm element movable to and from between two positions said oscillating diaphragm element being suspended so that the elastic forces act toward a equilibrium position between the two positions with said illumination unit additionally comprising a control unit for controlling the oscillating diaphragm element by means of electrostatic forces such that said diaphragm element blocks the light channel of the microshutter in one of the two positions, the illumination unit characterized in that at least one of the light emitters (1) is arranged to illuminate at least two microshutters via a first lens arrangement (2;

23), said lens arrangement comprising at least one microlens with respect to each microshutter so that the light emitted by the light emitter or emitters is focused on or in the vicinity of the optical axis of the light channel (6;

26) of the individual microshutters.

18. An illumination unit for point illumination of a medium comprising at least one light emitter arranged to illuminate at least one illumination face via a microshutter arrangement, said microshutter arrangement comprising a plurality of microshutters, each microshutter comprising a light channel and an electrically activatable diaphragm device (4) associated with it, characterized in that at least one of the light emitters (1) is arranged to illuminate at least two microshutters via a first lens arrangement (2;

23), said lens arrangement comprising at least one microlens with respect to each microshutter so that the light emitted by the light emitter or emitters is focused on or in the vicinity of the optical axis of the light channel (6;

26) of the individual microshutters and said illumination unit additionally comprises optical means (98) for spreading the light beams emitted by the light channels over the illumination face.

19. A method of point illumination of a medium by means of at least one light emitter arranged to illuminate at least one illumination face via a microshutter arrangement, said microshutter arrangement comprising a plurality of microshutters, each microshutter comprising a light channel and an electrically activatable diaphragm device (4) associated with it, characterized in that at least one of the light emitters (1) is arranged to illuminate at least two microshutters via a first lens arrangement (2;

23), said lens arrangement comprising at least one microlens arranged with respect to each microshutter so that the light emitted by the light emitter or emitters is focused on or in the vicinity of the optical axis of the light channel (6;

26) of the individual microshutter.

21. A method according to claim 19, characterized in that at least one of the light emitters is formed by an optical light guide (13;

29) which is optically connected to at least one light source.

20. A method of point illumination of a medium by means of at least one light emitter arranged to illuminate at least one illumination face via a microshutter arrangement, said microshutter arrangement comprising a plurality of microshutters, each microshutter comprising a light channel and an electrically activatable diaphragm device (4) associated with it, characterized in that at least one of the light emitters (1) is arranged to illuminate at least two microshutters via a first lens arrangement (2;

23), said lens arrangement comprising at least one microlens arranged with respect to each microshutter so that the light emitted by the light emitter or emitters is focused on or in the vicinity of the optical axis of the light channel (6;

26) of the individual microshutter and the method further including a second microlens arrangement arranged between the microshutters and the illumination face so that the light transmitted through the light channel (6;

26) of the individual microshutter is focused suitably on the illumination face (9;

28).