Head or face mounted image display apparatus

• US 6,195,207 B1
• Filed: 04/26/2000
• Issued: 02/27/2001
• Est. Priority Date: 05/18/1995
• Status: Expired due to Term

• Current Assignee: Olympus Optical Corporation Limited (Olympus Corporation)
• Original Assignee: Olympus Optical Corporation Limited (Olympus Corporation)
• Inventors: Takahashi, Koichi
• Primary Examiner(s): Epps, Georgia
• Assistant Examiner(s): THOMPSON, TIMOTHY J
• Application Number:
  US09/558,627
• Time in Patent Office: 307 Days
• Field of Search: 359/630, 359/637, 359/631, 359/633, 359/627, 359/628, 359/629
• US Class Current: 359/637
• CPC Class Codes: G02B 17/0816 off-axis or unobscured systems in which not all of the mirrors share a common axis of rotational symmetry, e.g. at least one of the mirrors is warped, tilted or decentered with respect to the other elements
• CPC Class Codes: G02B 17/086 wherein the system is made of a single block of optical material, e.g. solid catadioptric systems
• CPC Class Codes: G02B 2027/011 comprising device for correcting geometrical aberrations, distortion
• CPC Class Codes: G02B 2027/0116 comprising devices for correcting chromatic aberration
• CPC Class Codes: G02B 2027/0132 comprising binocular systems
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• CPC Class Codes: G02B 27/017 Head mounted
• CPC Class Codes: G02B 27/0172 characterised by optical features

Abstract

The present invention is an optical apparatus, e.g. an image display apparatus, which enables observation of a clear image at a wide field angle with substantially no reduction in the brightness of the observation image, and which is extremely small in size and light in weight and hence unlikely to cause the observer to be fatigued. The optical apparatus has an image display device (6), and an ocular optical system (7) for leading an image of the image display device (6) to an observer'"'"'s eyeball (1). The ocular optical system (7) includes, in order from the image side, a third surface (5) which forms an entrance surface, a first surface (3) which forms both a reflecting surface and an exit surface, and a second surface (4) which forms a reflecting surface. The first to third surfaces (3 to 5) are integrally formed with a medium put therebetween which has a refractive index larger than 1. A bundle of light rays emitted from the image display device (6) enters the ocular optical system (7) while being refracted by the third surface (5) and is internally reflected by the first surface (3) and reflected by the second surface (4). Then, the ray bundle is incident on the first surface (3) again and refracted thereby so as to be projected into the observer'"'"'s eyeball with the observer'"'"'s iris position or eyeball rolling center as the exit pupil (1).

Claims

1. An optical apparatus comprising;

an image-forming member that forms an image to be observed, and

an ocular optical system provided to lead said image to an eyeball of an observer, wherein

said ocular optical system includes, in order from an image side thereof, a third surface that forms an entrance surface, a first surface that forms both a reflecting surface and an exit surface, and a second surface that forms a reflecting surface, said first, second and third surfaces being integrally formed to face each other across a medium having a refractive index larger than 1,

at least one of said first, second and third surfaces is formed from a rotationally asymmetric curved surface that corrects aberration produced by a decentered surface, and

a chromatic aberration correcting member located between said image-forming member and the eyeball of said observer to correct chromatic aberration produced by said ocular optical system.

2. An optical apparatus according to claim 1, further comprising:

a fitting member fitted to a head of said observer to retain said image-forming member, said ocular optical system and said chromatic aberration correcting member being in front of said observer.

3. An optical apparatus according to claim 1 or 2, wherein said chromatic aberration correcting member corrects at least chromatic aberration produced by the first surface of said ocular optical system when said first surface acts as an exit surface.

4. An optical apparatus according to claim 1 or 2, wherein said chromatic aberration correcting member is a surface that produces chromatic aberration which is approximately equal in quantity but opposite in sign to chromatic aberration produced by said first surface of said ocular optical system.

5. An optical apparatus according to claim 3, wherein said chromatic aberration correcting member comprises at least one optical surface having refracting action.

6. An optical apparatus according to claim 1 or 2, wherein said chromatic aberration correcting member is placed between said first surface and said second surface of said ocular optical system.

7. An optical apparatus according to claim 6, wherein said chromatic aberration correcting member comprises at least one optical surface having refracting action.

8. An optical apparatus according to claim 1 or 2, wherein said chromatic aberration correcting member is placed between the first surface of said ocular optical system and the eyeball of said observer.

9. An optical apparatus according to claim 8, wherein said chromatic aberration correcting member comprises at least one optical surface having refracting action.

10. An optical apparatus according to claim 1 or 2, wherein said chromatic aberration correcting member is located between the third surface of said ocular optical system and an image display device.

11. An optical apparatus according to claim 10, wherein said chromatic aberration correcting member comprises at least one optical surface having refracting action.

12. An optical apparatus according to claim 1 or 2, wherein reflection at the first surface of said ocular optical system is total reflection.

13. An optical apparatus according to claim 1 or 2, wherein the second surface of said ocular optical system is a reflecting surface arranged to give a positive power to a light beam by reflection.

14. An optical apparatus according to claim 1 or 2, wherein the first, second and third surfaces of said ocular optical system are each formed from a rotationally asymmetric curved surface that corrects aberration due to decentration.