Head-up display for aircraft with a curved windshield

• US 20030011536A1
• Filed: 06/25/2002
• Published: 01/16/2003
• Est. Priority Date: 11/14/2000
• Status: Active Grant

• Current Assignee: Thales SA
• Original Assignee: Thales SA
• Inventors: Bignolles, Laurent, Darrieux, Jean-Marc, Chevreau, Yannick
• Granted Patent: US 6,819,496 B2
• Time in Patent Office: Days
• US Class Current: 345/7
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence

Abstract

The invention relates to the field of head-up sights for an aircraft having a curved windshield.

It is a head-up sight, for an aircraft with a curved windshield (5), the windshield being external to the sight, which can project at infinity a symbology intended to be superimposed onto the external scene, comprising a combination of optical elements (2, 21, 22, 23, 3, 4, 41, 42, 7) bent at an angle to a folding mirror (3, 7), the folding mirror (7) having a curved shape adapted to correct the parallax associated with the optical power of the windshield (5).

The invention is especially applicable to aircraft having a cylindrical or conical windshield.

Claims

1. A head-up sight, for an aircraft with a curved windshield (5), the windshield being external to the sight, which can project at infinity a symbology intended to be superimposed onto the external scene, comprising a combination of optical elements (2, 21, 22, 23, 3, 4, 41, 42, 7) bent at an angle to a folding mirror (3, 7), characterized in that the folding mirror (7) has a curved shape adapted to correct the parallax associated with the optical power of the windshield (5).

2. The head-up sight as claimed in claim 1, characterized in that the shape of the folding mirror (7) is of the same type as that of the windshield (5).

3. The head-up sight as claimed in either of the preceding claims, characterized in that the folding mirror (7) is concave.

4. The head-up sight as claimed in any one of the preceding claims, characterized in that the shape of the folding mirror (7) is conical.

5. The head-up-sight as claimed in any one of claims 1 to 4, characterized in that the shape of the folding mirror (7) is cylindrical.

6. The head-up sight as claimed in claim 5, characterized in that the radius of curvature of the folding mirror (7) is several meters.

7. The head-up sight as claimed in any one of the preceding claims, characterized in that the folding mirror (7) consists of a glass plate on which a surface reflecting in the visible region is deposited.

8. The head-up sight as claimed in claim 7, characterized in that the reflecting surface is a metal coating.

9. The head-up sight as claimed in either of claims 7 and 8, characterized in that the reflecting surface is multilayer so as to be, on the one hand, transparent in the infrared region and, on the other hand, reflecting in the visible region.

10. The head-up sight as claimed in any one of the preceding claims, characterized in that the head-up sight comprises a cathode-ray tube (1) and a combination of optical elements (2, 21, 22, 23, 3, 4, 41, 42, 7) which combination comprises successively, from the cathode-ray tube (1) to the optical output of the head-up sight, a rear group (2), the folding mirror (7) and a front group (4).

11. A method of retrofitting an aircraft comprising a head-up sight and having a curved windshield (5), consisting solely, in order to obtain a head-up sight according to any one of the preceding claims, in substituting a folding mirror (7) of curved shape adapted to correct the parallax associated with the windshield (5) of said aircraft for the existing flat folding mirror (3) in the head-up sight of said aircraft.