Variable mirror, optical apparatus and decentered optical system which include variable mirror, variable-optical characteristic optical element or combination thereof

• US 6,464,363 B1
• Filed: 03/16/2000
• Issued: 10/15/2002
• Est. Priority Date: 03/17/1999
• Status: Expired due to Term

• Current Assignee: Olympus Optical Corporation Limited (Olympus Corporation)
• Original Assignee: Olympus Optical Corporation Limited (Olympus Corporation)
• Inventors: Murakami, Kenji, Hayakawa, Kazuhito, Tokuda, Kazunari, Nishioka, Kimihiko
• Primary Examiner(s): Robinson, Mark A
• Application Number:
  US09/526,963
• Time in Patent Office: 943 Days
• Field of Search: 359/846, 359/847, 359/848, 359/849, 359/223, 359/224, 359/857, 359/858, 359/859, 359/868, 359/869
• US Class Current: 359/846
• 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 17/0832 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 17/0848 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 17/0896 with variable magnification or multiple imaging planes, including multispectral systems systems with only refractive elements G02B15/14
• CPC Class Codes: G02B 2006/12104 Mirror; Reflectors or the like
• CPC Class Codes: G02B 2027/011 comprising device for correcting geometrical aberrations, distortion
• CPC Class Codes: G02B 2027/0132 comprising binocular systems
• CPC Class Codes: G02B 2027/0138 comprising image capture systems, e.g. camera
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• CPC Class Codes: G02B 26/0825 the reflecting element being a flexible sheet or membrane, e.g. for varying the focus flexible mirrors for cosmetic use A45D42/24
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G02B 26/085 the reflecting means being moved or deformed by electromagnetic means
• CPC Class Codes: G02B 26/0858 the reflecting means being moved or deformed by piezoelectric means
• CPC Class Codes: G02B 27/017 Head mounted
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 27/646 compensating for small deviations, e.g. due to vibration or shake movement of one or more optical elements for control of motion blur in cameras, projectors or printers G03B2205/0007; image stabilisation in cameras peculiar to the presence or use of an electronic image sensor H04N23/68
• CPC Class Codes: G02B 7/102 controlled by a microcomputer cameras with interchangeable lenses G03B17/14
• CPC Class Codes: G02B 7/1821 for rotating or oscillating mirrors
• CPC Class Codes: G02C 7/00 Optical parts characterised by the material G02B1/00
• CPC Class Codes: G02F 1/1334 : based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/29 : for the control of the position or the direction of light beams, i.e. deflection
• CPC Class Codes: G02F 1/294 : Variable focal length devices
• CPC Class Codes: G02F 2203/50 : Phase-only modulation
• CPC Class Codes: G03B 17/17 : with reflectors arranged in beam forming the photographic image, e.g. for reducing dimensions of camera
• CPC Class Codes: G03B 2205/0023 : by tilting or inclining one or more optical elements with respect to the optical axis

Abstract

A variable mirror that is readily formable and can be readily and precisely changed into various configurations as desired is provided. The variable mirror includes a mirror body formed of an elastic or flexible material and having one surface functioning as a reflecting surface. The mirror body is capable of changing the reflecting surface configuration. The rigidity of the mirror body varies in a direction parallel to the one surface.

Claims

1. A decentered optical system comprising, at least, a front optical surface and a variable optical surface, which are disposed along a direction in which a light beam travels;

said front optical surface being a reflecting surface reflecting the light beam obliquely incident thereon in an oblique direction;

said variable optical surface being formed by an active reflecting optical element that reflects the light beam obliquely incident thereon in an oblique direction and changes a configuration of a reflecting surface thereof to change a focal length;

wherein a driving member drives said active reflecting optical element so that the configuration of the reflecting surface thereof is changed;

wherein, when driven by said driving member, said active reflecting optical element changes the configuration of the reflecting surface into a rotationally asymmetric curved surface configuration that corrects rotationally asymmetric decentration aberrations produced by the light beam obliquely incident thereon; and

wherein when an optical path length of an axial principal ray from said front optical surface to the variable optical surface of said active reflecting optical element is denoted by Δ

L_f, the following condition (2) is satisfied;

7. A decentered optical system according to any one of claims 1 to 4, wherein said driving member continuously changes an amount of change in the focal length caused by varying the surface configuration of said active reflecting optical element, thereby providing a zooming function.

8. A decentered optical system according to any one of claims 1 to 4, wherein said driving member stepwisely changes an amount of change in the focal length caused by varying the surface configuration of said active reflecting optical element, thereby allowing a plurality of focal lengths to be switched from one to another.

9. A decentered optical system according to any one of claims 1 to 4, wherein said driving member changes the focal length by varying the surface configuration of said active reflecting optical element.

10. A decentered optical system according to any one of claims 1 to 4, wherein said active reflecting optical element is a variable-configuration mirror member capable of changing a mirror configuration.

11. A decentered optical system according to claim 10, wherein when a maximum amount of change in the mirror configuration of said variable-configuration mirror member is denoted by Δ

μ

_max, the following condition is satisfied;

13. A decentered optical system as claimed in any one of claims 1 to 4, 5 and 6, wherein focus adjustment or diopter adjustment is effected by said active reflecting optical element.

14. A decentered optical system as claimed in any one of claims 1 to 4, 5 and 6, wherein zooming or correction of aberration variations caused by zooming is effected by said active reflecting optical element.

17. An image-forming optical system comprising:

said decentered optical system according to claims 1 or 3;

an aperture stop positioned in front of said front optical surface; and

an image pickup device positioned behind said variable optical surface;

wherein said decentered optical system forms an object image on a light-receiving surface of said image pickup device.

19. A viewing optical system comprising:

said decentered optical system according to claims 1 or 3;

an image forming device positioned in front of said front optical surface; and

an optical pupil position formed behind said variable optical surface;

wherein said decentered optical system leads an observation image formed by said image forming device to said optical pupil position, thereby allowing an observer placing an eyeball at said optical pupil position to view said observation image.

2. A decentered optical system comprising, at least, a variable optical surface and a rear optical surface, which are disposed along a direction in which a light beam travels;

said rear optical surface being a reflecting surface reflecting the light beam obliquely incident thereon in an oblique direction;

said variable optical surface being formed by an active reflecting optical element that reflects the light beam obliquely incident thereon in an oblique direction and changes a configuration of a reflecting surface thereof to change a focal length;

wherein a driving member drives said active reflecting optical element so that the configuration of the reflecting surface thereof is changed;

wherein, when driven by said driving member, said active reflecting optical element changes the configuration of the reflecting surface into a rotationally asymmetric curved surface configuration that corrects rotationally asymmetric decentration aberrations produced by the light beam obliquely incident thereon; and

wherein when an optical path length of an axial principal ray from the variable optical surface of said active reflecting optical element to said rear optical surface is denoted by Δ

L_b, the following condition (3) is satisfied;

18. An image-forming optical system comprising:

said decentered optical system according to claims 2 or 4;

an aperture stop positioned in front of said variable optical surface; and

an image pickup device positioned behind said rear optical surface;

wherein said decentered optical system forms an object image on a light-receiving surface of said image pickup device.

20. A viewing optical system comprising:

said decentered optical system according to claims 2 or 4;

an image forming device positioned in front of said variable optical surface; and

an optical pupil position formed behind said rear optical surface;

wherein said decentered optical system leads an observation image formed by said image forming device to said optical pupil position, thereby allowing an observer placing an eyeball at said optical pupil position to view said observation image.

3. A decentered optical system comprising, at least, a front optical surface and a variable optical surface, which are disposed along a direction in which a light beam travels;

said front optical surface being a transmitting surface transmitting the light beam;

said variable optical surface being formed by an active reflecting optical element that reflects the light beam obliquely incident thereon in an oblique direction and changes a configuration of a reflecting surface thereof to change a focal length;

wherein a driving member drives said active reflecting optical element so that the configuration of the reflecting surface thereof is changed;

wherein, when driven by said driving member, said active reflecting optical element changes the configuration of the reflecting surface into a rotationally asymmetric curved surface configuration that corrects rotationally asymmetric decentration aberrations produced by the light beam obliquely incident thereon; and

wherein when an optical path length of an axial principal ray from said front optical surface to said variable optical surface is denoted by Δ

L_f, the following condition (2) is satisfied;

15. A decentered optical system according to claim 3, wherein said front optical surface is provided on a prism member.

4. A decentered optical system comprising, at least, a variable optical surface and a rear optical surface, which are disposed along a direction in which a light beam travels;

said rear optical surface being a transmitting surface transmitting the light beam;

said variable optical surface being formed by an active reflecting optical element that reflects the light beam obliquely incident thereon in an oblique direction and changes a configuration of a reflecting surface thereof to change a focal length;

wherein a driving member drives said active reflecting optical element so that the configuration of the reflecting surface thereof is changed;

wherein, when driven by said driving member, said active reflecting optical element changes the configuration of the reflecting surface into a rotationally asymmetric curved surface configuration that corrects rotationally asymmetric decentration aberrations produced by the light beam obliquely incident thereon; and

wherein when an optical path length of an axial principal ray from the variable optical surface of said active reflecting optical element to said rear optical surface is denoted by Δ

L_b, the following condition (3) is satisfied;

16. A decentered optical system according to claim 4, wherein said rear optical surface is provided on a prism member.

5. A decentered optical system comprising, at least, a front optical surface, a variable optical surface, and a rear optical surface, which are disposed along a direction in which a light beam travels;

said front optical surface and said rear optical surface being provided on a prism member;

said front optical surface being an exit surface through which the light beam exits from an inside of said prism member to an outside thereof;

said variable optical surface being formed by an active reflecting optical element that reflects the light beam obliquely incident thereon in an oblique direction and changes a configuration of a reflecting surface thereof to change a focal length;

said rear optical surface being an entrance surface through which the light beam reflected from said active reflecting optical element enters said prism member;

wherein a driving member drives said active reflecting optical element so that the configuration of the reflecting surface thereof is changed;

wherein, when driven by said driving member, said active reflecting optical element changes the configuration of the reflecting surface into a rotationally asymmetric curved surface configuration that corrects rotationally asymmetric decentration aberrations produced by the light beam obliquely incident thereon; and

wherein when an angle formed between a line normal to said front optical surface at a position where an optical axis exits from said exit surface and the optical axis leading to said exit surface within said prism member is denoted by θ

_ex, and a refractive index of a medium of said prism member is denoted by n, and further a refractive index of a medium between said prism member and said active reflecting optical element is denoted by n′

, the condition of n>

n′

is satisfied, and further the following condition (4) is satisfied;

12. A decentered optical system as claimed in claims 5 or 6, wherein when an angle formed between an axial principal ray incident on said active reflecting optical element and a line normal to the reflecting surface of said active reflecting optical element at a position where the axial principal ray intersects the reflecting surface is denoted by o, the following condition is satisfied:

6. A decentered optical system comprising, at least, a front optical surface, a variable optical surface, and a rear optical surface, which are disposed along a direction in which a light beam travels;

said front optical surface and said rear optical surface being provided on a prism member;

said front optical surface being an exit surface through which the light beam exits from an inside of said prism member to an outside thereof;

said variable optical surface being formed by an active reflecting optical element that reflects the light beam obliquely incident thereon in an oblique direction and changes a configuration of a reflecting surface thereof to change a focal length;

said rear optical surface being an entrance surface through which the light beam reflected from said active reflecting optical element enters said prism member;

wherein a driving member drives said active reflecting optical element so that the configuration of the reflecting surface thereof is changed;

wherein, when driven by said driving member, said active reflecting optical element changes the configuration of the reflecting surface into a rotationally asymmetric curved surface configuration that corrects rotationally asymmetric decentration aberrations produced by the light beam obliquely incident thereon; and

wherein when an angle formed between a line normal to said entrance surface at a position where an optical axis reflected from said active reflecting optical element is incident on said entrance surface and the optical axis leading to said entrance surface outside said prism member is denoted by θ

_in, and a refractive index of a medium of said prism member is denoted by n, and further a refractive index of a medium between said prism member and said active reflecting optical element is denoted by n′

, the condition of n<

n′

is satisfied, and further the following condition (5) is satisfied;