Head mount type display device

• US 6,690,516 B2
• Filed: 01/30/2001
• Issued: 02/10/2004
• Est. Priority Date: 01/31/2000
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Fujitsu Limited
• Inventors: Saito, Seiichi, Aritake, Hirokazu, Tomita, Junji
• Primary Examiner(s): Mack, Ricky
• Application Number:
  US09/772,745
• Publication Number:
  US 20010010598A1
• Time in Patent Office: 1,106 Days
• Field of Search: 359/630, 359/631, 359/633, 359/618, 359/629, 359/632, 362/268
• US Class Current: 359/630
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 5/30 Polarising elements light-modulating devices with active elements G02F1/00

Abstract

The head mount type display device includes an optical system having a light emitting element, a display element illuminated by the light emitting element, and an image forming element 20 for producing an image. The display element is arranged between the image forming element and the first focal point of the image forming element at a position nearer to the first focal point of the image forming element. A virtual image of the display element is formed by the image forming element 20 and the light emitted by the light emitting element is focussed on a second focal point of the image forming element. It is designed such that the eye of an observer is located on the second focal point when use. In another form, the optical system includes first and second elliptical concave mirrors with respective ones of focal points arranged at a common position.

Claims

1. A display device arranged in front of an eye of an observer, comprising:

a light emitting element;

a display element illuminated by said light emitting element; and

an image forming element allowing light passing through said display element to pass therethrough;

wherein said display element is arranged between said image forming element and a first focal point of said image forming element at a position near to said first focal point of said image forming element, said image forming element both transmitting and reflecting light, and forming a virtual image of said display element, and said light emitting element having its emitted light focused by said image forming element at a second focal point of said image forming element.

2. A display device according to claim 1, further comprising an optical element arranged between said light emitting element and said display element for converting the light incident to said display element into a parallel light.

3. A display device according to claim 2, wherein the display element is a transmission type display element, the optical element is arranged on one side of the display element, and the image forming element is arranged on the other side of the display element.

4. A display device according to claim 2, wherein the display clement is a reflection type display element, and the optical element and the image forming element are formed by a common element.