Illuminating unit comprising an optical element

1. An illuminating unit comprising:

a luminous means;

a first optical element comprising a radiation entrance surface facing toward the luminous means, and a radiation exit surface facing away from the luminous means;

at least one first holographic element disposed in or on the first optical element and configured as a beam shaping element for shaping radiation emitted from the luminous means; and

one of a second holographic element, a microlens array, and a microprism array arranged in or on the first optical element or another optical element of said illuminating unit, said first holographic element and said one of a second holographic element, a microlens array, and a microprism array being configured to reduce chromatic aberrations;

wherein a second optical element is included as primary optics for the luminous means between the luminous means and the radiation entrance surface of the first optical element; and

wherein the second optical element is a light guide.

2. The illuminating unit as claimed in claim 1 , wherein the first optical element functions as a lens for the radiation emitted from the luminous means.

3. The illuminating unit as claimed in claim 1 , wherein the first optical element has a height h of 8 mm or less.

4. The illuminating unit as claimed in claim 1 , wherein the radiation exit surface of the first optical element is a substantially flat surface.

5. The illuminating unit as claimed in claim 1 , wherein the first holographic element is a volume hologram formed in the first optical element.

6. The illuminating unit as claimed in claim 1 , wherein the first holographic element is a surface hologram formed on a surface of the first optical element.

7. The illuminating unit as claimed in claim 1 , wherein the luminous means comprises at least one LED chip.

8. The illuminating unit as claimed in claim 1 , wherein the luminous means comprises a plurality of LED chips.

9. The illuminating unit as claimed in claim 8 , wherein the plurality of LED chips are configured to be driven individually.

10. The illuminating unit as claimed in claim 1 , wherein the one of a second holographic element, a microlens array, and a microprism array is disposed on at least one of the radiation entrance surface and the radiation exit surface of said first optical element.

11. The illuminating unit as claimed in claim 1 , wherein at least one of the radiation entrance surface and the radiation exit surface has a reflection reducing coating.

12. The illuminating unit as claimed in claim 1 , wherein the radiation entrance surface of the first optical element is a substantially flat surface.

13. The illuminating unit as claimed in claim 1 , wherein the first optical element has at least one cutout at the radiation entrance surface.

14. The illuminating unit as claimed in claim 13 , wherein the cutout is concavely curved.

15. The illuminating unit as claimed in claim 13 , wherein the cutout has the shape of a conical frustum.

16. The illuminating unit as claimed in claim 1 , wherein the radiation entrance surface has a Fresnel lens structure.

17. The illuminating unit as claimed in claim 1 , wherein an immersion liquid is contained between the luminous means and the first optical element.

18. The illuminating unit as claimed in claim 1 , wherein a distance d between the luminous means and the radiation entrance surface is 1 mm or less.

19. The illuminating unit as claimed in claim 1 , wherein the first optical element is produced by injection molding.

20. The illuminating unit as claimed in claim 1 , wherein the first holographic element includes a recording of a three dimensional graphic object that is reproduced during operation of the illuminating unit.

21. The illuminating unit as claimed in claim 20 , wherein the three dimensional graphic object is a security feature.

22. The illuminating unit as claimed in claim 1 , wherein the illuminating unit is a motor vehicle headlight.

23. The illuminating unit as claimed in claim 1 , wherein the first optical element includes a switchable diffractive element.

24. An illuminating unit comprising:

a luminous means;

a first optical element comprising a radiation entrance surface facing toward the luminous means, a radiation exit surface facing away from the luminous means;

at least one first holographic element disposed in or on the first optical element and configured as a beam shaping element for shaping radiation emitted from the luminous means; and

one of a second holographic element, a microlens array, and a microprism array arranged in or on the first optical element or another optical element of said illuminating unit, said first holographic element and said one of a second holographic element, a microlens array, and a microprism array being configured to reduce chromatic aberrations;

wherein the first optical element includes a switchable diffractive element.