Visual display apparatus

• US 5,793,339 A
• Filed: 11/08/1994
• Issued: 08/11/1998
• Est. Priority Date: 11/11/1993
• 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): Liang, Regina
• Application Number:
  US08/337,825
• Time in Patent Office: 1,372 Days
• Field of Search: 345/7, 345/8, 345/9, 340/980, 348/53, 348/115, 359/630, 359/631, 359/13, 359/728, 434/44
• US Class Current: 345/7
• CPC Class Codes: G02B 17/08 Catadioptric systems used in non-imaging applications G02B19/00
• CPC Class Codes: G02B 17/0852 having a field corrector only
• CPC Class Codes: G02B 2027/011 comprising device for correcting geometrical aberrations, distortion
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: H04N 13/339 using spatial multiplexing H04N13/337 takes precedence
• CPC Class Codes: H04N 13/344 with head-mounted left-right displays

Abstract

A compact and lightweight visual display apparatus which enables observation of an image that is clear throughout the image field at a field angle of 120° when the user observes with both eyes, and which has a large exit pupil diameter. The visual display apparatus has a two-dimensional image display device (6) for displaying an image for observation, a relay optical system (5) for projecting a real image of the two-dimensional image display device (6) in the air, an ocular magnifier (3) for projecting the real image in the air as an enlarged image and for reflectively bending an optical axis, and a decentered correcting optical system (4) disposed between the relay optical system (5) and the ocular magnifier (3) and having surfaces (41 and 42) decentered with respect to each other. The decentered correcting optical system (4) is arranged such that the vertex (43) of the surface (41) which is closer to the ocular magnifier (3) lies inward of the visual axis (7) after it has been reflected by the ocular magnifier (3), and the ocular magnifier-side surface (41) is an aspherical surface formed from such a curved surface that the refractive power reaches a maximum in the vicinity of the surface vertex (43) and becomes weaker as the distance from the vertex (43) increases toward the outer side. The apparatus may be arranged to correct the diopter by making at least one optical element movable.

Claims

1. A visual display apparatus comprising a two-dimensional image display device for displaying an image for observation, a relay optical system for projecting a real image of said two-dimensional image display device in the air, an ocular magnifier for projecting said real image in the air as an enlarged image and for reflectively bending an optical axis, and a decentered correcting optical system disposed between said relay optical system and said ocular magnifier and having surfaces decentered with respect to each other,

wherein said decentered correcting optical system is arranged such that a vertex of the surface thereof which is closer to said ocular magnifier lies inward of a visual axis after it has been reflected by said ocular magnifier, and an ocular magnifier-side surface is an aspherical surface which is formed from such a curved surface that refractive power reaches a maximum in the vicinity of the surface vertex and becomes weaker as the distance from the surface vertex increases toward the outer side.

2. A visual display apparatus according to claim 1, which satisfies the following condition:

space="preserve" listing-type="equation">1.3<

|R.sub.ym /E.sub.xp |<

2.6 (1)

where R_ym is the radius of curvature in a horizontal cross-section of said ocular magnifier containing the observer'"'"'s visual axis when he or she looks straight forward, and E_xp is the distance from the exit pupil position of said visual display apparatus to the center of said ocular magnifier in the direction of the observer'"'"'s visual axis when he or she looks straight forward.

3. A visual display apparatus according to claim 1, which satisfies the following condition:

space="preserve" listing-type="equation">-10°

<

θ

.sub.1 <

30°

(2)

where θ

_l is the angle of inclination of said ocular magnifier-side surface of said decentered correcting optical system with respect to the visual axis after it has been reflected by said ocular magnifier.

4. A visual display apparatus according to claim 1, wherein said decentered correcting optical system is relatively thick in wall thickness in the vicinity of the vertex of said ocular magnifier-side surface and relatively thin at the outer side thereof.

5. A visual display apparatus according to claim 1, wherein all lenses constituting said relay optical system are coaxial with respect to each other.

6. A visual display apparatus according to claim 1, wherein said two-dimensional image display device is tilted with respect to a center axis of said relay optical system.

7. A visual display apparatus according to claim 1, which satisfies the following condition:

space="preserve" listing-type="equation">0.4<

R.sub.yl /R.sub.y2 <

1.2 (3)

where R_yl is the radius of curvature in a YZ-plane of said ocular magnifier-side surface of said decentered correcting optical system, and R_y2 is the radius of curvature in the YZ-plane of the relay optical system-side surface of said decentered correcting optical system.

8. A visual display apparatus according to claim 1, wherein either said ocular magnifier or said decentered correcting optical system has an anamorphic surface.

9. A visual display apparatus according to claim 1, wherein either said ocular magnifier or said decentered correcting optical system has an aspherical surface.

13. A visual display apparatus according to any one of claims 1 to 12, which is accommodated in a body of an image display apparatus and has a support member whereby said image display apparatus body can be fitted on the observer'"'"'s face.

14. A visual display apparatus according to claim 13, wherein said image display apparatus body is further provided with means for transmitting sound to the observer.

15. A visual display apparatus according to claim 14, wherein said image display apparatus body further has a reproducing device for transmitting image and sound signals to said two-dimensional image display device and said sound transmitting means, respectively.

10. A visual display apparatus comprising:

a two-dimensional image display device for displaying an image for observation;

a relay optical system for projecting a real image of said two-dimensional image display device in the air;

an ocular magnifier for projecting said real image in the air as an enlarged image and for reflectively bending an optical axis; and

a decentered correcting optical system disposed between said relay optical system and said ocular magnifier and having surfaces decentered with respect to each other,

wherein at least one lens constituting said relay optical system moves in a space reserved between said two-dimensional image display device and said ocular magnifier to correct diopter, and

wherein even if at least one lens constituting said relay optical system is moved, there is no change in the distance from the observer'"'"'s pupil to said two-dimensional image display device.

16. A visual display apparatus according to claim 10, 11, or 12, which is accommodated in a body of an image display apparatus and has a support member whereby said image display apparatus body can be fitted on the observer'"'"'s face.

17. A visual display apparatus according to claim 10, 11 or 12, wherein said at least one lens constituting said relay optical system, or said decentered correcting optical system or said ocular magnifier moves with an eccentricity from the optical axis.

18. A visual display apparatus according to claim 17, which is accommodated in a body of an image display apparatus and has a support member whereby said image display apparatus body can be fitted on the observer'"'"'s face.

11. A visual display apparatus comprising:

a two-dimensional image display device for displaying an image for observation;

a relay optical system for projecting a real image of said two-dimensional image display device in the air;

an ocular magnifier for projecting said real image in the air as an enlarged image and for reflectively bending an optical axis; and

a decentered correcting optical system disposed between said relay optical system and said ocular magnifier and having surfaces decentered with respect to each other,

wherein said decentered correcting optical system moves in a space reserved between said two-dimensional image display device and said ocular magnifier to correct diopter, and

wherein even if said decentered correcting optical system is moved, there is no change in the distance from the observer'"'"'s pupil to said two-dimensional image display device.

12. A visual display apparatus comprising:

a two-dimensional image display device for displaying an image for observation;

a relay optical system for projecting a real image of said two-dimensional image display device in the air;

an ocular magnifier for projecting said real image in the air as an enlarged image and for reflectively bending an optical axis; and

a decentered correcting optical system disposed between said relay optical system and said ocular magnifier and having surfaces decentered with respect to each other,

wherein said ocular magnifier is moved to correct diopter, and

wherein even if said ocular magnifier is moved, there is no change in the distance from the observer'"'"'s pupil to said two-dimensional image display device.