DIFFRACTIVE HEAD-UP DISPLAY DEVICE PROVIDED WITH A DEVICE FOR ADJUSTING THE POSITION OF THE VIRTUAL IMAGE

• US 20110267701A1
• Filed: 12/09/2009
• Published: 11/03/2011
• Est. Priority Date: 12/09/2008
• Status: Active Grant

• Current Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated), Universite De Strasbourg (Financière Meeschaert SA)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated), Universite De Strasbourg (Financière Meeschaert SA)
• Inventors: Hafidi, Idriss El, Moussa, Hassan, Tupinier, Laurent
• Granted Patent: US 8,351,123 B2
• Time in Patent Office: Days
• US Class Current: 359/630
• CPC Class Codes: G02B 2027/0123 comprising devices increasing the field of view
• CPC Class Codes: G02B 2027/0159 with mechanical means other than scaning means for positioning the whole image
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G03B 21/142 Adjusting of projection optics
• CPC Class Codes: G03B 21/28 Reflectors in projection beam in illumination beam G03B21/2066
• CPC Class Codes: G03B 21/62 Translucent screens
• CPC Class Codes: G03B 3/04 adjusting position of image plane without moving lens

Abstract

A diffractive head up display device that includes a projection unit that uses a display to project an image through a projection window of an image mask, and towards a diffractive combiner. The display and the mask are moveable at right angles to the axis of the projection light beam, so that the adjustment of the position of the virtual image in the field of view of the observer, for example the driver of a vehicle, is obtained by translation of the display and of the mask.

Claims

1. Diffractive head up display device comprising a projection unit that projects an image in a direction towards a diffractive combiner to display a virtual image in a field of view of an observer, wherein the projection unit (16) comprises a light source (26) that projects a projection light beam directed along an axis towards a display configured to project the image onto the diffractive combiner, wherein the projection unit comprises a projection mask that defines a projection window positioned between the combiner and the display, wherein the area of the projection window corresponds a display area of the display, wherein the light beam uniformly illuminates an area of the display larger than the display area defined by the mask, wherein the display and the mask are movable in a direction substantially normal to the axis of the projection light beam, so that adjustment of the position of the virtual image in the field of view of the observer is obtained by movement of the display and of the mask.

2. Diffractive head up display device as described in claim 1, wherein the diffractive combiner is made in the form of a transparent plate provided with a series of diffractive optical elements arranged at the surface on a single layer, wherein a downward angle of view of the virtual image determined by the optical elements on the diffractive combiner based on a determined angle of illumination.

3. Diffractive head up display device as described in claim 2, wherein the diffractive combiner is formed by one of injection into a mold and embossing by a mold, the said mold corresponding to a recording of a diffractive structure in relief comprising interference fringes themselves obtained by exposure of a photo-resistant layer to two interfering light beams.

4. Diffractive head up display device as described in claim 1, wherein the mask is fixed on the output face of the display.

5. Diffractive head up display device as described in claim 1, wherein the display is a liquid crystal display.

6. Diffractive head up display device as described in claim 1, wherein the display device comprises a control device that controls the position of the display and of the mask.