Head-up display

• US 6,636,277 B2
• Filed: 12/07/2001
• Issued: 10/21/2003
• Est. Priority Date: 12/15/2000
• Status: Expired due to Fees

• Current Assignee: Continental Automotive GmbH (Continental AG)
• Original Assignee: Siemens AG
• Inventors: Mayer, Ralf, Ludewig, Bernd, Eberhardt, Bernd
• Primary Examiner(s): TON, MINH TOAN T
• Application Number:
  US10/013,035
• Publication Number:
  US 20020089613A1
• Time in Patent Office: 683 Days
• Field of Search: 349/11, 349/96, 349/5, 349/9, 359/487, 359/493, 359/494, 359/485, 359/630, 359/631
• US Class Current: 349/11
• 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
• CPC Class Codes: G02B 5/30 Polarising elements light-modulating devices with active elements G02F1/00

Abstract

A head-up display for vehicles, in which information from a display device is projected onto a transparent projection area, the display device has two transparent screens between which a liquid crystal substance and electrodes are arranged, polarized light penetrating through the liquid crystal substance, the liquid crystal substance rotating the polarized light penetrating through the liquid crystal substance in a plane of polarization in a manner dependent on the driving of the electrodes with a voltage. The polarized light emerging form the liquid crystal substance is not sent through a polarizer, but rather is polarized by the reflection at the transparent projection area or at one or more other reflectors which is or are arranged in the beam path of the polarized light between the liquid crystal substance and the transparent projection area.

Claims

1. A head-up display for a vehicle, in which information from a display device (10, 13) is projected onto a transparent projection area (11), the display device (10, 13) having two transparent screens (1, 2) between which a liquid crystal substance (6) and electrodes (5) are arranged,

polarized light penetrating through the liquid crystal substance (6),

the liquid crystal substance (6) rotating the polarized light penetrating through the liquid crystal substance in a plane of polarization in a manner dependent on the driving of the electrodes (5) with a voltage,

wherein the polarized light emerging from the liquid crystal substance (6) is not sent through a polarizer, but is polarized by the reflection at the transparent projection area or at least one reflectors which is or are arranged in beam path of the polarized light between the liquid crystal substance (6) and the transparent projection area (11).

2. The head-up display as claimed in claim 1, wherein a front screen (12) of the vehicle is used as the transparent projection area (11).

3. The device as claimed in claim 2, wherein a polarizer (7) is arranged between the display device (13) and the light source (14).

4. The device as claimed in claim 1, wherein a polarizer (7) is arranged between the display device (13) and a light source (14).