Compact helmet mounted display

• US 4,761,056 A
• Filed: 03/27/1987
• Issued: 08/02/1988
• Est. Priority Date: 03/27/1987
• Status: Expired due to Term

• Current Assignee: Kaiser Aerospace & Electronics Corporation
• Original Assignee: Kaiser Aerospace & Electronics Corporation
• Inventors: Melzer, James E., Tirums, Andrew T., Evans, Charles D., Larkin, Eric W.
• Primary Examiner(s): Corbin, John K.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/030,495
• Time in Patent Office: 494 Days
• Field of Search: 350/174, 350/169, 350/538, 350/504, 350/602, 350/619, 350/622, 358/250, 358/93
• US Class Current: 359/631
• CPC Class Codes: A42B 3/042 Optical devices night vision goggles G02B23/12
• CPC Class Codes: G02B 2027/0143 the two eyes not being equipped with identical nor symmetrical optical devices
• CPC Class Codes: G02B 27/017 Head mounted
• CPC Class Codes: G02B 27/0172 characterised by optical features

Abstract

A display apparatus for use with headgear, includes in combination visor means adapted to attach to the headgear and having a visor viewing area segment positioned in the line-of-sight of a wearer of the headgear. Optical display generating means are adapted to be attached to the headgear. Parabolic mirror means are interposed in the optical path from the optical display generating means to the visor viewing area segment. Fold mirror means, including at least one fold mirror positioned to receive the image from the parabolic mirror means for directing the image to the visor viewing area segment, is provided, whereby the size and curvature of the visor can be minimized without affecting transmission of the image.

Claims

1. A display apparatus for use with headgear comprising, in combination:

visor means adapted to attach to said headgear and having at least one concave semi-reflecting curved surface directed inwardly of the headgear and which, when the headgear is being worn, is at or is movable to a position at which it intercepts the forward line-of-sight of an eye of the wearer and is characterized in that the concave semi-reflecting surface is part of a paraboloid having an axis of rotation;

an optical projector above the level of the wearer'"'"'s eyes, by means of which luminous data is directed at said semi-reflecting surface for reflection thereby to the wearer'"'"'s eye so that the wearer is presented with a virtual image of the luminous data within a predetermined field of view centered on the wearer'"'"'s forward line-of-sight, said optical projector adapted to be attached to said headgear;

parabolic mirror means interposed in the optical path from said optical projector to said semi-reflecting surface of said visor, whose shape, dimensions and position are such that rays from said optical projector are reflected in said parabolic mirror means; and

fold mirror means, including first and second fold mirrors, said first fold mirror whose shape, dimension and position enable it to receive the rays from said parabolic mirror means and to direct the rays to said second fold mirror, said second fold mirror whose shape, dimension and position enable it to direct rays received from said first fold mirror to said semi-reflecting surface of said visor.

2. A display apparatus as defined in claim 1 wherein said parabolic mirror means is attached to said visor means.

3. A display apparatus as defined in claim 1 wherein said parabolic mirror means is integrally formed with said visor means.

4. A display apparatus as defined in claim 1 wherein said parabolic mirror means is a local parabolic surface section of said visor means having enhanced reflectivity.

5. A display apparatus as defined in claim 1 wherein said first and second fold mirrors are attached to said headgear.

6. A display appparatus as defined in claim 1 wherein said semi-reflecting curved surface of said visor means permits both the reflected virtual image of the luminous data and direct images in the wearer'"'"'s line-of-sight to reach the eyes of the headgear wearer.

7. A display apparatus for use with headgear, comprising in combination:

visor means adapted to attach to the headgear and having a parabolic visor segment positioned to be in the normal line-of-sight of the headgear wearer;

optical display generating means adapted to be attached to the headgear;

parabolic mirror means interposed in the optical path from said optical display generating means to said parabolic visor segment; and

fold mirror means including first and second fold mirrors, said first fold mirror being positioned to receive the image from said parabolic mirror means and to direct the image to said second fold mirror, said second fold mirror being positioned to direct images received from said first fold mirror to said parabolic visor segment,

whereby the size and curvature of the visor can be minimized without affecting transmission of the image.

8. A display apparatus as defined in claim 7 wherein said parabolic mirror means is attached to said visor means.

9. A display apparatus as defined in claim 7 wherein said parabolic mirror means is integrally formed with said visor means.

10. A display apparatus as defined in claim 7 wherein said parabolic mirror means is a local parabolic surface section of said visor means having enhanced reflectivity.

11. A display apparatus as defined in claim 7 wherein said first and second fold mirrors are attached to said headgear.

12. A display apparatus as defined in claim 7 wherein said parabolic visor segment permits both the reflected virtual image of the images from said optical display generating means and direct images in the headgear wearer'"'"'s line-of-sight to reach the eyes of the headgear wearer.