MICROMECHANICAL LIGHT DEFLECTION DEVICE

Abstract

A micromechanical light deflection device. The device includes a movable beam-deflecting element that is designed to deflect an input light beam into an output light beam, and a static beam-deflecting device having a plurality of differently oriented surfaces that are situated in the beam path of light for the movable beam-deflecting element in such a way that an input light beam for the movable beam-deflecting element and/or an output light beam from the movable beam-deflecting element passes through two of the differently oriented surfaces of the static beam-deflecting device.

Claims

1-11. (canceled)

12. A micromechanical light deflection device, comprising: a movable beam-deflecting element configured to deflect an input light beam into an output light beam; and a static beam-deflecting device having a plurality of differently oriented surfaces that are situated in a beam path of light for the movable beam-deflecting element in such a way that an input light beam for the movable beam-deflecting element and/or an output light beam from the movable beam-deflecting element, passes through two of the differently oriented surfaces of the static beam-deflecting device.

13. The micromechanical light deflection device as recited in claim 12, wherein the static beam-deflecting device has two optically separated regions.

14. The micromechanical light deflection device as recited in claim 12, wherein the static beam-deflecting device is a cover for the movable beam-deflecting element.

15. The micromechanical light deflection device as recited in claim 12, wherein the static beam-deflecting device is in the form of at least one prism.

16. The micromechanical light deflection device as recited in claim 15, wherein the static beam-deflecting device is in the form of a double prism including two individual prisms, the two individual prisms being configured mirror-symmetrically to one another.

17. The micromechanical light deflection device as recited in claim 12, wherein the static beam-deflecting device is situated on an optically transparent cover for the movable beam-deflecting element.

18. The micromechanical light deflection device as recited in claim 17, wherein the static beam-deflecting device is fastened on the optically transparent cover by an adhesive, the static beam-deflecting element, the adhesive, and the optically transparent cover having substantially the same index of refraction for at least one wavelength range.

19. The micromechanical light deflection device as recited in claim 17, wherein the optically transparent cover is anti-reflective.

20. The micromechanical light deflection device as recited in claim 17, wherein the optically transparent cover has an anti-reflective coating.

21. The micromechanical light deflection device as recited in claim 12, wherein a beamforming element for the input light beam and/or the output light beam is situated on the static beam-deflecting device (3, 6).

22. The micromechanical light deflection device as recited in claim 12, wherein the movable beam-deflecting element is a micromirror.

23. A method for deflecting light, the method comprising the following steps: deflecting, by a moveable beam deflecting element, an input light beam into an output light beam; and passing through, by the input light beam for the beam-deflecting element and/or by the output light beam from the beam deflecting element, two differently oriented surfaces of a static beam-deflecting device situated in a beam path of light for the movable beam-deflecting element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] FIG. 1 shows, in schematic form, a micromechanical light deflection device according to a specific embodiment of the present invention.

[0026] FIG. 2 shows a conventional micromechanical light deflection device.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

[0027] FIG. 1 shows, in schematic form, a micromechanical light deflection device in cross-section according to a specific embodiment of the present invention.

[0028] FIG. 1 shows a micromechanical light deflection device 10. This device includes a micromechanical mirror 5 that is protected by a cover glass 4.

[0029] Micromechanical mirror 5, or micromirror for short, is rotatable about an axis perpendicular to the plane of the drawing, and about an axis parallel to the plane of the drawing of FIG. 1, by an angle as indicated by the dashed lines, and in this way can deflect an incident light beam 2 from a light source 1, for example from a laser, a light-emitting diode, etc. Going out from light source 1, input light beam 2 impinges on micromirror 5 via a first prism 3 and a cover glass 4. Input light be 2 is reflected by micromirror 5, is deflected by a particular angle, and enters, via cover glass 4 and a second prism 6, into an object space as output light beam 2. Between the two prisms 3, 6, there is situated an absorption layer 7. Overall, a double prism 3, 6 is thus situated on cover 4. Light source 1 couples input light beam 2 frontally, from the front, onto micromechanical light deflection device 10, enabling a larger adjustment tolerance when coupling in input light beam 2. Prisms 3, 6 here have a wedge angle 11 of approximately 35, which suppresses multiple reflections due to parallel beams.

[0030] Specifically, prisms 3, 6 are constructed as follows: in cross-section, the two prisms 3, 6 form right triangles having sides 31, 32, 33, 61, 62, 63. Side 32, 62 is the hypotenuse of the respective triangle, and is here inclined in each case by the wedge angle 9 of 35 relative to the plane of cover glass 4. Side 33, 63, i.e., the respective side opposite wedge angle 11, is situated parallel to the respective other prism 3, 6. Absorption layer 7 is situated between these two sides 33, 63. Sides 31, 61, i.e. the sides opposite the angles, are situated parallel to the plane of cover glass 4 on cover glass 4, in particular cemented to cover glass 4 by an optical bonding method, for example a UV adhesive, an epoxy resin, etc. Prisms 3, 6 can be produced by injection molding of plastic or blank pressing of glasses, enabling low costs with simultaneously complex constructive shapes.

[0031] Here, cover glass 4 in FIG. 1 is made flat, and is not tilted relative to the null position of micromirror 5. As already stated, the two prisms 3, 6 are situated on this cover glass 4, and are preferably glued onto the surface of cover glass 4. First prism 3, on which input light beam 2 going out from light source 1 impinges, here has a roof surface 32 that reflects as well as possible, and has side surfaces 33, 63 that are not transparent to light, or are as absorbent as possible. The two prisms 3, 6 are optically separated from one another by absorption layer 7. Cover glass 4 can be produced by rolling, enabling lower costs and a high piece count.

[0032] Cover glass 4 in FIG. 1 can also be omitted. In other words, the two prisms 3, 6 can also be attached, in particular glued, directly onto a housing of micromirror 5 without cover glass 4, taking over its function. In addition, wedge angle 11 of prisms 3, 6, and/or the material of prisms 3, 6, can be adapted in relation to the index of refraction in order to save material and/or costs and to simplify production. In general, for example, wedge angles 11 between 0 and 75, in particular between 10 and 50, are also possible.

[0033] In addition, as is shown in FIG. 1, a beamforming element 8, for example a spherical lens, can be situated on surface 32 of first prism 3, or can be made in one piece with first prism 3. Additional beamforming elements can then be omitted. Likewise, one or more beamforming elements 8 can be situated on second prism 6.

[0034] FIG. 2 shows a conventional micromechanical deflecting device. An input light beam 2 is deflected by a micromirror 5 after passing through a cover glass 4. If an imaginary receiving surface 9, situated substantially in semicircular fashion around mirror 5, is now regarded, reflexes 12 can clearly be recognized that occur in particular due to the large tilt angle of cover glass 4 relative to the depicted null position of micromirror 5.

[0035] In sum, the present invention, in particular at least one of its specific embodiments, has the following advantages: [0036] Suppression of static reflexes. [0037] At least partial suppression of dynamic reflexes. [0038] Simple, low-cost production. [0039] Modular construction possible. [0040] Mechanical stabilization of a cover glass, or generally of a cover, possible. [0041] Simple coupling of light into the micromechanical light deflection device. [0042] Simple production process for the covering and static beam-deflecting element, in particular prism. [0043] Larger tolerances, and thus easier adjustment.

[0044] Although the present invention has been described on the basis of preferred specific embodiments, it is not limited thereto, but can be modified in many ways.