Projection unit for a head-up display

• US 20060209419A1
• Filed: 03/16/2006
• Published: 09/21/2006
• Est. Priority Date: 03/16/2005
• Status: Active Grant

• Current Assignee: Sypro Optics GmbH (Jabil Inc.)
• Original Assignee: CARL Zeiss JENA GmbH (Carl-Zeiss-Stiftung)
• Inventors: Jahn, Dirk, Dobschal, Hans-Juergen
• Granted Patent: US 7,298,557 B2
• Time in Patent Office: Days
• US Class Current: 359/630
• CPC Class Codes: G02B 2027/011 comprising device for correcting geometrical aberrations, distortion
• CPC Class Codes: G02B 2027/0118 comprising devices for improving the contrast of the display / brillance control visibility
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence

Abstract

The invention is directed to a projection unit for a head-up display comprising an image generator, a mirror and a refractive lens which are arranged in a housing one behind the other in the light propagation direction. The beam path is directed to a windshield. The invention is characterized in that the mirror has a concave reflection surface, and the lens has a free-form surface at least on one of the optically active surfaces (D-U and/or D-O).

Claims

1. A projection unit for a head-up display comprising:

an image generator;

a mirror; and

a refractive lens;

said image generator, mirror and refractive lens being arranged in a housing one behind the other in light propagation direction;

a beam path of said projection unit being directed to a windshield;

said mirror having a light-bundling reflection surface; and

said lens having a free-form surface at least on one of the optically active surfaces (D-U and/or D-0)

2. The projection unit for a head-up display according to claim 1, wherein one of the optical surfaces of the lens has a cylindrical component extending in a direction from the driver to the front-seat passenger.

3. The projection unit for a head-up display according to claim 1, wherein the lens has a plano-convex to concave-convex cylindrical component.

4. The projection unit for a head-up display according to claim 3, wherein the surface of the lens facing the windshield has a constant concave radius.

5. The projection unit for a head-up display according to claim 3, wherein the surface of the lens facing the mirror has a constant convex radius.

6. The projection unit for a head-up display according to claim 1, wherein the surface (D-0) of the lens facing the windshield is a concave free-form surface and the surface (D-U) of the lens facing the mirror is a convex free-form surface.

7. The projection unit for a head-up display according to claim 1, wherein additional spherical or plane mirrors are arranged between the mirror and the image generator for beam folding and beam shaping.

8. The projection unit for a head-up display according to claim 1, wherein the lens simultaneously serves as a cover for the opening of the dashboard scoop.

9. The projection unit for a head-up display according to claim 1, wherein the concave reflection surface of the mirror has a spherical radius.

10. The projection unit for a head-up display according to claim 1, wherein the concave reflection surface of the mirror is aspheric.