HEAD-UP DISPLAY APPARATUS

• US 3,709,589 A
• Filed: 12/28/1970
• Issued: 01/09/1973
• Est. Priority Date: 12/28/1970
• Status: Expired due to Term

• Current Assignee: Edward Lawrence Lamb, Kenneth Gordon Mcainsh, Ralph David Smith
• Original Assignee: Edward Lawrence Lamb, Kenneth Gordon Mcainsh, Ralph David Smith
• Inventors: Lamb, Edward Lawrence, McAinsh, Kenneth Gordon, Smith, Ralph David
• Primary Examiner(s): Martin, Jr., William D.
• Application Number:
  US05/101,774
• Time in Patent Office: 743 Days
• Field of Search: 353/14,13,12,11,28,94,82
• US Class Current: 353/13
• CPC Class Codes: G02B 2027/0156 with optionally usable elements
• CPC Class Codes: G02B 2027/0187 slaved to motion of at least a part of the body of the user, e.g. head, eye
• CPC Class Codes: G02B 27/01 Head-up displays
• CPC Class Codes: G02B 27/0149 characterised by mechanical features G02B27/0176 takes precedence

Abstract

Head-up display apparatus that includes a collimator for projecting a display on to a partially-transparent reflector, also includes first and second display-producing means for providing respectively main and auxiliary displays of information, and means for selecting which of the displays is projected on to the reflector. Selection of which of the two display-producing means acts as the source of the projected display is effected by a handle that is movable between first and second positions to control rotation of a sleeve that is coupled to both display-producing means. Movement of the handle in one direction moves the first display-producing means longitudinally away from the collimator means so as to provide a space between this display-producing means and the collimator means, and also pivots the second display-producing means into the said space along an arcuate path substantially normal to the direction of movement of the first display-producing means. The first displayproducing means is a cathode-ray tube, and the second displayproducing means, for use in the event that the cathode-ray-tube display fails, is an illuminated graticule or a device in which an incandescent filament is strung into a desired displaypattern.

Claims

1. A head-up display apparatus for a craft, comprising two display-producing means, collimator means having an optical axis, means defining a display position substantially in a focal plane of said collimator means, means mounting a first of said displayproducing means in said display position, a partially-transparent reflector mounted in the image field of the collimator means, said collimator means projecting onto the reflector the display provided at said display position so that the display projected is visible to an observer in the craft viewing a distant scene through the reflector, and display-changing means operable selectively to replace the said first display-producing means at said display position by the second display-producing means, said display-changing means comprising means operable selectively to withdraw said first display-producing means from said display position along a path substantially parallel to said optical axis at said position, and means for moving said second displayproducing means into said display position in place of said first display-producing means.

2. An apparatus according to claim 1, wherein one of the display-producing means comprises an electrically-operated display device including a substantially planar panel, a gas-tight housing having a transparent wall portion, means mounting said panel within the housing with said panel facing said wall portion, an electric filament carried by said panel with at least part of the filament extending across said panel intermediate said panel and said wall portion in the form of a symbol to be displayed, and means for electrically connecting said filament to an energizing source whereby to enable said filament to be energized from outside the housing to provide an illuminated disPlay of said symbol through said wall portion.

3. An apparatus according to claim 2, wherein said electric filament is constituted by electrical resistance wire, and said panel defines holes through which the wire is threaded.

4. An apparatus according to claim 2, wherein said electric filament is constituted by a printed circuit formed on the surface of said panel facing said wall portion.

5. An apparatus according to claim 1, wherein one of the display-producing means comprises a window, a graticule on the window in the form of a symbol to be displayed, an electric lamp for illuminating the window, and a light-reflecting surface for directing light-rays from the electric lamp towards the window.

6. An apparatus according to claim 1, wherein one of the display-producing means is a cathode-ray tube for providing a main display of information, and the other of the display-producing means is an auxiliary-display means for providing a static display of information that can be used in the event of failure of the main display.

7. Apparatus for providing a head-up display in the line of sight of an observer, comprising two display-producing means, selection means operable to select one of the two display-producing means as the source of said head-up display, collimator means for optical projection of the display provided by the said selected display-producing means, and a partially-transparent reflector mounted to reflect the projected display into the line of sight of the observer, said selection means comprising first transport means operable to move a first of said display-producing means along a straight-line path from said collimator to a withdrawn position spaced therefrom, second transport means operable when said first display-producing means is moved from said collimator to move the second display-producing means transversely of said straight-line path into the space between the said withdrawn position and the collimator, and a selector movable from a first position to a second position to operate said first and second transport means to select the second display-producing means in place of said first display-producing means as the source of said head-up display.

8. Apparatus according to claim 7 wherein the said second transport means is means operable to move the said second display-producing means along an arcuate path transverse to said straight-line path.

9. An apparatus according to claim 7, wherein said first display-producing means is a cathode-ray tube for providing a main display of information, and said second display-producing means is an auxiliary-display means for providing a display of information that can be used as an alternative to said main display in the event of failure of the said cathode-ray tube.

10. An apparatus according to claim 7 wherein the selection means includes a rotatably-mounted sleeve, drive means coupled between the said selector and the sleeve to rotate the sleeve in response to movement of the said selector between said first and second positions, the direction of rotation of the sleeve being dependent on whether the movement of the said selector is toward said first position or toward said second position, first coupling means coupling the sleeve to the said first display-producing means to move the first display-producing means away from the collimator means when the sleeve is rotated in one direction and to move the first display-producing means toward the collimator means when the sleeve is rotated in the opposite direction, and second coupling means coupling the sleeve to the said second display-producing means to move the second display-producing means toward the collimator means when the sleeve is rotated in said one direction and to move the second display-producing means away from the collimator means when the sleeve is rotated in said opposite direction.

11. A head-up display apparatus for a craft, comprising two display-producing means, collimator means having an optical axis, means defining a diSplay position substantially in a focal plane of said collimator means, means mounting a first of said display-producing means in said display position, a partially-transparent reflector mounted in the image field of the collimator means, said collimator means projecting onto the reflector the display provided at said display position so that the display projected is visible to an observer in the craft viewing a distant scene through the reflector, and display-changing means operable selectively to replace the said first display-producing means at said display position by the second display-producing means, said display-changing means comprising means operable selectively to move said first display-producing means from said display position, means mounting said second display-producing means for pivotal movement into said display position, and means for effecting said pivotal movement of said second display-producing means into said display position in place of said first display-producing means.