Omniramic optical system having central coverage means which is associated with a camera, projector, or similar article

• US 6,333,826 B1
• Filed: 03/07/1998
• Issued: 12/25/2001
• Est. Priority Date: 04/16/1997
• Status: Expired due to Term

• Current Assignee: Jeffrey R. Charles
• Original Assignee: Jeffrey R. Charles
• Inventors: Charles, Jeffrey R.
• Primary Examiner(s): Sugarman, Scott J.
• Application Number:
  US09/036,612
• Time in Patent Office: 1,389 Days
• Field of Search: 359/726-736, 359/725
• US Class Current: 359/725
• CPC Class Codes: G02B 13/06 Panoramic objectives; So-called "sky lenses" including panoramic objectives having reflecting surfaces

Abstract

The present invention relates to an omniramic wide angle optical system which is associated with a camera, projector, medical instrument, surveillance system, flight control system, or similar article. The optical system typically consists of a Cassegrain system having a strongly curved convex reflecting surface with a prolate aspheric figure, a secondary reflector surface, and a modular imaging and correcting lens system. The invention further relates to the distribution of still or motion picture image elements by optical or electronic means, whereby the entire image or any subset thereof is converted from a two dimensional annular image or a segment thereof to a viewable horizontal image or a subset thereof; or, from a horizontal format image or a subset thereof into an annular image or a segment thereof. The present invention also relates to the capture, integration, and display of images having three dimensional information and the capture and presentation of sound and other attributes of real or artificially generated subject matter.

Claims

1. An optical system comprising:

a convex primary reflector having radial symmetry,

said primary reflector being in optical communication with a great circle surrounding it, said great circle being perpendicular to the optical axis of said primary reflector,

said primary reflector having sufficient curvature to be in optical communication with a substantial area in front and behind the plane of said great circle,

said primary reflector having an optically transparent central zone,

a secondary reflector having radial symmetry,

said secondary reflector being coaxially disposed in front of said primary reflector,

said secondary reflector having its reflective surface facing the reflective surface of said primary reflector,

said secondary reflector being in optical communication with said great circle surrounding said primary reflector and said area in front and behind the plane of said great circle by means of reflection from said primary reflector,

whereby said optical system produces a virtual image of said great circle and said area above and below its plane, said virtual image being annular,

said virtual image being visible from a vantage point behind said optically transparent central zone of said primary reflector due to said vantage point being in optical communication with said great circle and said area in front and behind the plane of said great circle by means of reflection from said secondary reflector and said primary reflector,

means for mounting said secondary reflector and said primary reflector,

said means providing a protective darkened shield around the perimeter of said secondary reflector, said shield also acting as a light baffle,

said means for mounting providing stable support and alignment of said primary reflector and said secondary reflector without causing deformation thereof,

said means for mounting providing for attachment of said optical system to an article having a focal surface,

said mounting means not relying on the structure of said primary reflector surface substrate to support said article,

said mounting means facilitating use of said optical system in any orientation,

said article being associated with a refracting lens system, said refracting lens system being disposed coaxial to said optical system, both being associated with the formation of a real image of said virtual image at said focal surface,

whereby said optical system combined with said article facilitates the geometric conversion of said great circle and said area in front and behind the plane of said great circle into a real annular image at the focal surface of said article and the geometric conversion of a two dimensional annular image into a three dimensional projected image.

2. Apparatus according to claim 1 in which said primary reflector comprises a surface of revolution, said surface of revolution having a prolate aspheric figure.

3. Apparatus according to claim 1 in which said primary reflector comprises a surface of revolution, said surface of revolution having a prolate aspheric figure, the virtual image produced by said primary reflector having a constant radial image scale when said primary reflector is viewed from an axial vantage point having an equivalent optical distance of one to four times the diameter of said primary reflector from the apex of said primary reflector.

4. Apparatus according to claim 1 in which said primary reflector comprises a surface of revolution, said surface of revolution having a prolate aspheric figure, said prolate aspheric figure also being radially compressed inward toward the optical axis, whereby the surface said primary reflector is farther from being perpendicular with the optical axis at a zone which immediately surrounds said transparent central zone, whereby said vantage point behind said transparent central zone of said primary reflector is in optical communication with a smaller angular area in front of said great circle, thereby increasing the size of the central angular exclusion zone in front of said primary reflector while increasing the radial proportions of the area immediately surrounding the plane of said great circle, thereby resulting in a larger radial image scale for said area covered on a given image format, owing to the virtual absence of an imaged central obscuration area.

5. Apparatus according to claim 1 in which said primary reflector comprises a surface of revolution, said surface of revolution having a prolate aspheric figure, said prolate aspheric figure also being radially enlarged outward from the optical axis, whereby the surface said primary reflector is closer to perpendicular with the optical axis at a zone which immediately surrounds said transparent central zone, whereby said vantage point behind said transparent central zone of said primary reflector is in optical communication with a greater angular area in front of said great circle, thereby reducing the size of the central angular exclusion zone in front of said primary reflector, radially enlarged primary reflector also permitting said transparent central zone to be enlarged without affecting the field of view, said enlarged transparent zone permitting the use of large aperture refracting optics such as those associated with a camera or a projector, said secondary reflector with its associated mounting and shielding being relatively small in order to minimize obscuration of subject matter in front of said primary reflector, whereby said combination of attributes typically result in a conical obscuration having a diameter of less than 60 degrees.

6. Apparatus according to claim 1 in which said primary reflector comprises a surface of revolution, said surface of revolution having a prolate aspheric figure, said prolate aspheric figure also being torroidal as a result of being radially enlarged outward from the optical axis, whereby the surface of said primary reflector curves backward in the zone immediately surrounding said transparent central zone, whereby the radial zone of said primary reflector by which the inner zone of said secondary reflector is in optical communication with an axial point disposed at a finite distance in front of said optical system by means of reflection from said zone of said primary reflector has a larger diameter than said secondary reflector with its associated mounting and shielding, whereby said vantage point behind said transparent central zone of said primary reflector is in optical communication with the entire area in front of said great circle up to said axial point disposed at a finite distance in front of said primary reflector, thereby eliminating the central angular exclusion zone in front of said primary reflector, the only excluded area being confined to a narrow conical area extending from the perimeter of said secondary reflector with its associated mounting and shielding to said axial point disposed a finite distance in front of said primary reflector, said torroidal primary reflector also permitting said transparent central zone to be enlarged without affecting the field of view, said enlarged transparent zone permitting the use of large aperture refracting optics such as those associated with a camera or projector.

7. Apparatus according to claim 1 in which said primary reflector has a scalloped surface resulting in more than three identical convex lobes disposed evenly around its circumference, each lobe having more than twice the included angle as the angular circumference of the reflector body it occupies;

for example, as seen from the front, each lobe of an eight lobe reflector would occupy 45 degrees of the circumference;

therefore, each of said lobes would have more than 90 degrees of curvature as seen from the front;

said primary reflector providing a sectored virtual image, said image having the same number of sectors as said primary reflector has lobes, each of said sectors covering a circumferential angle of view of more than twice the circumferential angle occupied by each sector, whereby said virtual image covers each point in said great circle and said area in front and behind the plane of said great circle at least twice, thereby providing fully redundant coverage thereof;

said twice imaged points having circumferentially separated vantage points and being circumferentially separated in said virtual image, said redundant coverage providing three dimensional information for the entire area of coverage;

said optical system also being applicable to the projection of sectored images whereby said redundant images overlap and include three dimensional information;

the geometry of said optical system also being applicable for the basis of image processing techniques, algorithms, and software which are associated with viewing, analyzing, and otherwise utilizing images produced and reproduced by said optical system.

8. Apparatus according to claim 1 in which said primary reflector is made of optically transparent material, said optically transparent central zone of said primary reflector consisting of a hole in its reflective coating, the surface of said substrate being radially symmetrical within said hole in reflective coating.

9. Apparatus according to claim 8 in which said primary reflector substrate is plastic, said substrate also extending behind the perimeter of the reflecting surface and providing a protective rim behind said reflecting surface and providing a grip surface to facilitate handling without marring said reflective surface.

10. Apparatus according to claim 1 in which said optically transparent central zone of said primary reflector consists of a hole through said primary reflector substrate.

11. Apparatus according to claim 10 in which said primary reflector consists of a metal substrate having an electrolytically replicated figure.

12. Apparatus according to claim 6 further comprising a round baffle which may be attached to said secondary reflector with its associated mounting and shielding, said round baffle having longitudinal positioning means, whereby the shadow of said round baffle changes the distance of said axial point disposed a finite distance in front of said primary reflector, thereby providing means for said axial point to coincide with the distance of a front projection surface, thereby resulting in a seamless projection across the central part of a projection surface having a finite distance from said optical system, said apparatus being associated with the projection of images which completely surround the viewing participant.

13. Apparatus according to claim 6 in which said secondary reflector is a convex surface of revolution and said secondary reflector with its associated mounting and shielding having a diameter less than forty percent of the diameter of said primary reflector.

14. Apparatus according to claim 1 in which said secondary reflector is a convex surface of revolution, said convex surface of said secondary reflector also facilitating a smaller central obscuration angle.

15. Apparatus according to claim 1 in which said secondary reflector is a convex surface of revolution having a figure which is radially compressed inward toward from the optical axis in order to facilitate an unchanged field of view while not imaging said central transparent area in center of said primary reflector surface, thereby allowing the radial image scale of the covered area to be increased owing to the virtual absence of imaged central obscuration area, said convex surface also providing for the correction of off-axis aberrations.

16. Apparatus according to claim 1 in which the figure of said secondary reflector surface is an aspheric surface of revolution and provides means for the substantial correction of off-axis astigmatism which results from off-axis reflections off of said primary reflector, said apparatus further comprising refracting optics which are coaxial with said primary reflector and in longitudinal proximity to said transparent central zone of said primary reflector, said refracting optics correcting for residual aberrations from said primary reflector and said secondary reflector.

17. Apparatus according to claim 1 in which the substrate of said secondary reflector is transparent, having the reflective surface on the side opposite the primary reflector, the side of said substrate toward said primary reflector also having a surface of revolution and acting as a refracting surface, said refracting surface not being concentric with said secondary reflector surface, said refracting surface providing means for the substantial correction of off-axis astigmatism, said optical system further comprising refracting optics which are coaxial with said primary reflector and in longitudinal proximity to said transparent central zone of said primary reflector, said refracting optics correcting for residual aberrations from said primary reflector and said secondary reflector.

18. Apparatus according to claim 1 in which the secondary reflector is convex, further comprising an annular reflector which is coaxial with said secondary reflector, said annular reflector having sufficient curvature to cover the same area in front and behind said great circle as said primary reflector, said annular reflector having a longitudinal position which places its virtual image in close longitudinal proximity to that of said virtual image from said primary reflector as reflected in said secondary reflector, said virtual image from said annular reflector being visible from a vantage point behind said optically transparent central zone of said primary reflector due to said vantage point being in optical communication with said great circle and said area in front and behind the plane of said great circle by means of reflection from said annular reflector, said annular reflector providing redundant coverage, said redundant coverage providing three dimensional information for the entire area of coverage.

19. Apparatus according to claim 7 in which the secondary reflector is convex, further comprising an annular reflector which is coaxial with said secondary reflector, said annular reflector having sufficient curvature to cover the same area in front and behind said great circle as said primary reflector, said annular reflector having a longitudinal position which places its virtual image in close longitudinal proximity to that of said virtual image from said primary reflector, as reflected in said secondary reflector, said virtual image from said annular reflector being visible from a vantage point behind said optically transparent central zone of said primary reflector due to said vantage point being in optical communication with said great circle and said area in front and behind the plane of said great circle by means of reflection from said annular reflector, said annular reflector providing redundant coverage, said redundant coverage providing three dimensional information in all axes of the entire area of coverage.

20. Apparatus according to claim 1, further comprising at least one refracting optic, said refracting optics having a negative optical power, said refracting optics being coaxial with said primary reflector and in longitudinal proximity to said transparent central zone of said primary reflector, whereby said refracting optics provide for said vantage point behind said optically transparent central zone of said primary reflector to be moved to a substantial axial distance behind said transparent central zone, thereby allowing unobstructed optical communication between said moved vantage point and the entirety of said secondary reflector while allowing said transparent central zone of said primary reflector to have a relatively small diameter.

21. Apparatus according to claim 1 in which said mounting means for connecting said primary and said secondary reflector consist of a single darkened strut, said strut being coaxial with both reflectors, said strut having a diameter which is increased toward the end closest to said secondary reflector, said axial strut being coaxially supported in front of said vantage point by means of an optically transparent substrate, whereby the combination of said strut and transparent substrate provide stable support and provide alignment means for said secondary reflector without obstructing any of the subject matter.

22. Apparatus according to claim 21 in which said transparent substrate is in a cell, said cell being attached to mounting structures for said primary reflector and said article, said cell protruding in front of the apex of said primary reflector, said cell being removable, whereby said cell, said axial strut, and said secondary reflector assembly may be removed from the overall optical system as a unit, said axial strut also having adjustment means for its length, said darkened shield associated with said secondary reflector having provision to accept a variety of additional shields;

said shields being interchangeable, said shields being flat cylindrical, and conical;

the perimeter of said conical and cylindrical shields extending a short distance toward said primary reflector.

23. Apparatus according to claim 1 in which said secondary reflector shield has a conical shape of moderate taper, said conical shape having the largest diameter at the end toward said the primary reflector, said shield extending a moderate distance from around the perimeter of said secondary reflector toward a zone near the perimeter of said primary reflector.

24. Apparatus according to claim 1 in which said mounting means for connecting said primary and said secondary reflector consist of a single vane, said vane being off-axis and having a cross section of less than three degrees when viewed from the optical axis, said vane also having means to route electrical cable and similar articles, said vane further having means to accept an attachment providing means for occulting bright light sources which would otherwise cause flare;

whereby said vane provides stable support and alignment means for said secondary reflector.

25. Apparatus according to claim 1 in which said mounting means for connecting said primary and said secondary reflector consist of a solid transparent optical substrate between said reflectors, said reflectors being comprised of internal reflective surfaces in said optical substrate, said substrate having an outer surface which is convex except for the area occupied by the secondary reflector surface, said substrate also providing refracting means to extend the field of view of said primary reflector to cover the entire sphere around itself, whereby the front part of said substrate refracts light from an axial point a finite distance in front of said optical system around said secondary reflector surface and toward an inner zone of said primary reflector surface around said secondary reflector surface and toward, and whereby the rearward surface of said substrate refracts light from an axial point a finite distance behind the optical system toward the perimeter of said primary reflector surface at an angle which causes said axial point to be in optical communication with said vantage point behind said transparent central zone in said primary reflector surface, said optical system also having an opaque covering around the perimeter of said secondary reflector to act as a light baffle, said optical substrate provides permanent support and alignment of said reflector surfaces, said solid optical system further comprising refracting optics which are coaxial with said primary reflector and behind said transparent central zone of said primary reflector substrate, said refracting optics correcting for residual aberrations from said solid transparent optical substrate, said primary reflector and said secondary reflector, said corrected aberrations including astigmatism and lateral chromatic aberration;

said optics also forming a real image of said virtual image at said focal surface as well as correcting aberrations when the invention is used to project an annular image onto a three dimensional surface or into a three dimensional media.

26. Apparatus according to claim 1, further comprising a durable rim behind the perimeter of said primary reflector, said rim having a slightly larger diameter than said reflector and, said rim providing protection for said primary reflector and serving as a grip surface to permit handling said primary reflector without soiling the optical surface, said rim also having provision to accurately indicate the limit of coverage for said primary reflector, said rim also being connected to the mounting means for said article having a focal surface, said means for mounting and said rim also having provision for the attachment of accessories such as a clear storage and composition tube, a solar occulting disk, a level indicator, and data display devices, said level indicator and display devices being directly visible and imaged at said focal surface of said article.

27. Apparatus according to claim 1, further comprising a covering over the inner and outer boundaries of said primary reflector surface, said covering not being specular, said covering providing means to accurately indicate the limit of coverage for said primary reflector.

28. Apparatus according to claim 1, further comprising refracting lenses, said refracting lenses being coaxial with and having a diameter smaller than said primary reflector, said means for mounting including a cell for said refracting optics, said means for mounting positioning said refracting lenses between said secondary reflector and the focal surface of said article (typically behind said transparent central zone in said primary reflector), and in unobstructed optical communication with both, said refracting optics being in optical communication with said great circle surrounding said primary reflector by means of reflection from said primary reflector and said secondary reflector, said refracting lenses having a longitudinal position corresponding to said axial vantage point being in optical communication with said great circle and said area in front and behind the plane of said great circle by means of reflection from said secondary reflector and said primary reflector.

29. Apparatus according to claim 28, further comprising a filter holder.

30. Apparatus according to claim 28, further comprising a series of refracting lenses in interchangeable cells which are each capable of producing a real image from the overall optical system at the focal surface, said cells being of appropriate lengths to produce proper focus and image size at said focal surface when used with the intended articles having a focal surface, said cells also incorporating adaptation and mounting means for appropriate standardized adapters and camera and instrumentation mounting interfaces.

31. Apparatus according to claim 28 in which said refracting lenses are capable of producing a real annular image of the virtual image resulting from reflections off said primary reflector and said secondary reflector, said real image being at the focal surface of said article, mounting means for said refracting lenses also providing means for aperture adjustment.

32. Apparatus according to claim 31 in which said refracting lenses are of the zoom type, whereby images of different sizes are produced by adjusting the focal length of said zoom lens, whereby the same optical system can be used advantageously with different formats.

33. Apparatus according to claim 28 in which said refracting optics cause light rays from a given point in the subject to be parallel as they exit said optical system, thereby permitting use of said optical system in front of the fixed or interchangeable lens of an article having a focal surface.

34. Apparatus according to claim 28 in which said refracting lenses substantially correct curvature of the virtual image resulting from reflections off said primary reflector and said secondary reflector, thereby facilitating the optimum use of a flat focal surface, said refracting lenses typically comprising at least one refracting lens, at least one of which has negative optical power, said negative lens being positioned in relatively close proximity to said focal surface, further, where the application permits, said negative lens can be virtually in contact with said focal surface.

35. Apparatus according to claim 28 in which said refracting lenses substantially correct aberrations such as off-axis astigmatism which result from off-axis reflections off of said primary reflector and said secondary reflector.

36. Apparatus according to claim 28 in which the means for mounting includes a central cell, said cell protruding back behind said primary reflector, said protruding cell having a slot around its circumference which may be used to attach accessories and facilitate storage of the overall optical system in a case without any optical surfaces being in contact with said case, said cell being capable of supporting the weight of the entire optical system, attributes of said cell including said slot providing means to attach devices including a solar occulting disk, a level indicator, and data display devices;

at least some of said level indicator and display devices having provision to be directly visible and imaged at said focal surface of said article having a focal surface, said cell also having provision to house said refracting lenses.

37. Apparatus according to claim 1, further comprising an occulting attachment consisting of a small darkened occulting body which is affixed to the end of a thin wire of sufficient rigidity to prevent visible oscillation of said occulting body by wind or moderate motion, said attachment providing for reduction of flare by interrupting specular optical communication between a bright light source such as the sun and the focal surface of said article, said occulting body having an angular subtense larger than that of said bright light source as seen from the corresponding area of said virtual image from said primary reflector, thereby causing the image of said occulting body to completely cover said bright light source in the image formed by said optical system, said occultation resulting in a drastic reduction in unwanted reflections and flare;

said means for mounting having provision for attaching said occulting attachment to either said secondary reflector shield or a rim surrounding said primary reflector, said mounting means also providing for adjustment of said occulting body position.

38. Apparatus according to claim 1, further comprising a level indicator which is attached in close proximity to and slightly behind the perimeter of said primary reflector, said level indicator having easily distinguished indication means when observed from above and below, said secondary reflector being larger than what is required to image said primary reflector alone, said secondary reflector shield providing means for optical communication between said level and the focal surface of said article, said level being imaged at said focal surface by means of reflection via said secondary reflector, whereby said level is visible in the viewfinder of a camera, thereby facilitating effective hand held use of the optical system since the photographer and said camera are behind said primary reflector.

39. Apparatus according to claim 6, further comprising a periscopic optical system which points directly behind said optical system, said periscopic optical system being attached to said optical system at a point between the back of said primary reflector and the front of said article having a focal surface, said attachment means including a hollow tube, mirrors, and relay optics, said periscopic optical system having a circular field of view greater than the conical exclusion zone behind said primary reflector, the image from said periscopic optical system being imaged at a common focal surface with the annular image from said optical system, but in an area not occupied by said annular image, whereby the overall optical system images the entire sphere around itself on a single focal surface;

further, the use of a beam splitter on a transparent support which is in proximity to said focal surface will allow said circular image to be imaged in the center of said annular image.

40. Apparatus according to claim 1, used in conjunction with or incorporated into an article which includes a camera, photographic optical system, electronic image system, or motion picture system, said apparatus or article further comprising one or more illuminators which include flash illuminators to provide means for 360 degree illumination of the subject matter around said apparatus, said illumination being compatible with still and motion imaging.

41. Apparatus according to claim 40, associated with an electronic imaging sensor, provision of subject illumination means also employing a range gated flash illumination and imaging by means of an image sensor exposure of only a few to a few dozen nanoseconds, which in turn results in a shorter effective exposure for objects nearest the optical system;

further provision thereof in which a flash of illumination is actually directed through said optical system by means of a beam splitter prior to the initiation on an exposure.

42. Apparatus according to claim 1, further comprising an electronic imaging sensor capable of readout without mechanical shuttering, said optical system being capable of imaging said great circle and said area in front and behind the plane of said great circle;

said imaging being accomplished without any moving parts.

43. Apparatus according to claim 42, said combination also having provision and interface capability to facilitate real time digital processing of at least 24 images per second, whereby said optical system may also be associated with a separate full motion imaging system.

44. An optical system comprising:

a convex specular reflector having radial symmetry,

said primary reflector being in optical communication with a great circle surrounding it, said great circle being perpendicular to the optical axis of said primary reflector,

said primary reflector having sufficient curvature to be in optical communication with a substantial area in front and behind the plane of said great circle,

whereby said optical system produces a virtual image of said great circle and said area above and below its plane, said virtual image being annular,

said virtual image being visible from a vantage point in front of said primary reflector by means of said vantage point being in optical communication with said great circle and said area in front and behind the plane of said great circle by means of reflection from said convex reflector,

means for mounting and said reflector,

said means for mounting providing stable support and alignment of said primary reflector without causing deformation thereof,

said means for mounting providing for attachment of said optical system to an article having a focal surface,

said article being in front of said reflector,

said means providing a shield in close proximity to said article, said shield preventing stray light from entering from the side,

said mounting means facilitating unobstructed optical communication between said article and the utilized radial zones of said convex reflector,

said article being associated with a refracting lens system, said refracting lens system being disposed coaxial to said optical system, both being associated with the formation of a real image of said virtual image at said focal surface,

whereby said optical system combined with said article facilitate the geometric conversion of said great circle and said area in front and behind the plane of said great circle into a real annular image at the focal surface of said article as well as conversion of a flat annular image into a three dimensional image which surrounds the invention.

45. Apparatus according to claim 44 in which said convex reflector comprises a surface of revolution, said surface of revolution having a prolate aspheric figure, said prolate aspheric figure also being radially enlarged outward from the optical axis, whereby the surface said convex reflector is closer to perpendicular with the optical axis at a zone which immediately surrounds the reflection of said article having a focal surface, whereby said focal surface is in optical communication with a greater angular area in front of said great circle, thereby reducing the size of the central angular exclusion zone in front of said convex reflector caused by said article.

46. Apparatus according to claim 44 in which said convex reflector comprises a surface of revolution, said surface of revolution having a prolate aspheric figure, said prolate aspheric figure also being torroidal as a result of being radially enlarged outward from the optical axis, whereby the surface of said torroidal reflector curves backward in the zone immediately surrounding an area the size of a central obstruction, whereby the radial zone of said torroidal reflector by which the focal surface of said article is in optical communication with an axial point disposed at a finite distance in front of said optical system by means of reflection from said zone of said torroidal reflector has a larger diameter than the obstruction of said article, thereby eliminating the central angular exclusion zone in front of said reflector, the only excluded area being confined to a narrow conical area extending from the perimeter of said article with any associated mounting and shielding to said axial point disposed a finite distance in front of said torroidal reflector.

47. Apparatus according to claim 44 in which said convex reflector has a scalloped surface resulting in more than three identical convex lobes disposed evenly around its circumference, each lobe having more than twice the included angle as the angular circumference of the reflector body it occupies;

for example, as seen from the front, each lobe of an eight lobe reflector would occupy 45 degrees of the circumference;

therefore, each of said lobes would have more than 90 degrees of curvature as seen from the front;

said scalloped reflector providing a sectored virtual image, said image having the same number of sectors as said scalloped reflector has lobes, each of said sectors covering a circumferential angle of view of more than twice the circumferential angle occupied by each sector, whereby said virtual image covers each point in said great circle and said area in front and behind the plane of said great circle at least twice, thereby providing fully redundant coverage thereof;

said twice imaged points having circumferentially separated vantage points and being circumferentially separated in said virtual image, said redundant coverage providing three dimensional information for the entire area of coverage, said optical system also being applicable to the projection of sectored images whereby said redundant images overlap and include three dimensional information;

the geometry of said optical system are also being applicable for the basis of image processing techniques, algorithms, and software which are associated with viewing, analyzing, and otherwise utilizing images produced and reproduced by said optical system.

48. Apparatus according to claim 44, having a secondary reflector disposed coaxially in front of said convex reflector, said secondary reflector providing optical communication between said convex reflector and an axial vantage point in relatively close proximity to the apex of said convex reflector, said optical system further comprising refracting optics which produce a real annular image of the virtual image from said convex reflector, as reflected in said secondary reflector, said real image being formed at a shielded focal surface in close proximity to the front central surface of said convex reflector.

49. Apparatus according to claim 44, further comprising refracting lenses to correct for curvature of the virtual image and aberrations resulting from oblique reflections off said convex reflector, means for coaxially mounting said refracting lenses in front of said convex reflector, said mounting means including a cell for said refracting lenses and facilitating optical communication between said lenses, said article, and said primary reflector.

50. Apparatus according to claim 44 in which said mounting means consist of a single darkened strut, said strut being coaxial with said reflector, said strut having a diameter which is increased toward the end having the greatest distance the focal surface, said strut being coaxially supported in front of said article by means of an optically transparent substrate, whereby the combination of said strut and transparent substrate provide stable support and alignment means for said reflector, whereby said strut is thin enough to facilitate unobstructed optical communication between said article and said convex reflector, and between said convex reflector and said area in front and behind the plane of said great circle, said strut and said transparent substrate being of sufficient thickness to support the full weight of said article or said convex reflector.

51. Apparatus according to claim 50 in which said axial strut extends to near the optical center of imaging lenses associated with said article, said axial strut being hollow and facilitating the routing of wires without obstructing the subject, whereby said wires are routed from an axial to an off-axis position in close proximity to the optical center of said imaging lenses.

52. Apparatus according to claim 44 in which said mounting means for connecting said convex reflector and said article consist of a single vane, said vane being off-axis and having a cross section of less than three degrees when viewed from the optical axis, said vane also having means to route electrical cable and similar articles, said vane further having means to accept an attachment providing means for occulting bright light sources which would otherwise cause flare;

whereby said vane provides stable support and alignment means for an article including said article having a focal surface.

53. Apparatus according to claim 44, whereby said optical system is associated with a projector and a cylindrical projection surface to facilitate the geometric conversion of an annular image into a cylindrical projection around said optical system, whereby said convex reflector has a strong aspheric figure which facilitates correct image proportions and provides substantially constant projection brightness throughout the projection area, said cylindrical projection being applicable to display and printing.

54. Apparatus according to claim 44, whereby said optical system is associated with a projector and a spherical projection surface to facilitate the geometric conversion of an annular image into a spherical projection around said optical system, whereby said convex reflector is at the center of said spherical projection surface, said primary reflector having an aspheric figure which facilitates correct image proportions and constant projection brightness throughout the projection area.

55. Apparatus according to claim 44, whereby said optical system is associated with a projector and a spherical or semi spherical projection surface to facilitate the geometric conversion of an annular image into a spherical projection around said optical system, whereby said convex reflector is at a position other than the center of said spherical or semi spherical projection surface, said primary reflector having a strong aspheric figure which facilitates correct image proportions and constant projection brightness throughout the projection area in spite of the varying distances to said projection area, said apparatus being applicable to applications including virtual reality games and simulators.

56. Apparatus according to claim 44, whereby said optical system is used to image, display, and simulate phenomena associated with a total solar eclipse, said optical system being associated with a projector for display of said subject matter by projection, whereby said convex reflector is at a position other than the center of a spherical or semi spherical projection surface, said primary reflector having a strong aspheric figure which facilitates correct image proportions and constant projection brightness throughout the projection area in spite of the varying distances to said projection area.

57. Apparatus according to claim 55, in which a plurality of said optical systems are utilized to project images into multiple rooms, including multiple portal virtual reality suites and theaters;

said apparatus providing for the active masking of projection onto doorways which may be opened and closed, said masking accomplished by means of masks which are positioned in order to obstruct optical communication between an open doorway and the projection source, said masking means having provision to be synchronized with the opening and closing of doors and portals between different rooms;

further, a fixed mask may be used where a doorway is always open, said fixed mask being a separate part or a coating which is applied to the surface of said convex reflector.

58. Apparatus according to claim 55, whereby two of said optical systems are associated with a projector and a spherical or semi spherical projection surface, said optical systems being off center and on opposing ends of said spherical projection area, said arrangement facilitating the geometric conversion of two annular images into a spherical projection which covers the entire inside of said spherical projection area without obstructing the center of said projection area or requiring projector light to pass through the center of said spherical projection area, thereby allowing members of an audience to be positioned at and near the center of said projection area, said reflector also having provision for rear projection means onto an area surrounding the back surface of its perimeter.

59. Apparatus according to claim 58, further comprising means to suspend members of an audience at and near the center of said projection area, said suspension means having provision for lowering and raising an audience member to and from the floor, the surface of said projection area under the audience being comprised of inexpensive modular sections which can be replaced if soiled by a participant'"'"'s feet or the results of motion sickness.

60. Apparatus and means for geometric conversion of a 360 degree panoramic image into an annular image having polar projection, said apparatus comprising

a tilting easel which receives unexposed photographic media,

said easel having tilt adjustment means a concave focal surface which is curved according to a conical surface,

said focal surface having the smallest radius of curvature at the end closest to an enlarging lens;

said easel being combined with

a photographic enlarger having a light source and image carrier, an enlarging lens of shorter focal length than the lens which photographed the original image,

a tiltable lens standard to compensate for tilt of said easel in order to maintain high resolution, and

means for accurately positioning and securing said easel in optical communication with said enlarging lens;

said combination resulting in a greater enlargement of one end of a rectangular section of said panorama when a segment of said panorama is projected onto said easel so that its vertical angle of view (assuming the panorama is a conventional horizontal one) is distributed up the vertical tilt of said easel,

whereby the resulting image is a truncated wedge shape having borders and lines perpendicular to its vertical dimension which are smoothly curved as a result of being projected onto said conical focal surface of said easel,

whereby a complete smoothly curved and flat 360 degree annular image results from assembling a series of truncated wedge shaped images produced through use of said apparatus and means;

said apparatus and means also facilitating the incremental geometric conversion of an annular image into a rectangular image by implementing said means in reverse,

whereby a complete 360 degree rectangular panorama results from assembling a series of the rectangular images which are produced by utilization of said apparatus and means;

said apparatus and means also facilitating extraction and transformation of limited parts of an annular image.

61. Apparatus and means according to claim 60 whereby the geometric conversion of the image is accomplished by exposing photographic media through a slit combined with said tilting easel, said easel also having means to translate the photographic media under said slit, said easel being in optical communication with said photographic enlarger, with said photographic enlarger also having a rotating carrier for the original annular image, whereby the resulting 360 degree image and images extracted therefrom are continuous and seamless.

62. Apparatus and means according to claim 60, also associated with the use of an image acquired with an optical system having hyper hemispherical coverage to produce said original annular image, said optical system typically incorporating a reflector having a prolate aspheric figure which results in an annular image having increasing radial image scale toward its perimeter, whereby use and implementation of said apparatus and means will result in an undistorted 360 degree rectangular panorama and images extracted therefrom.

63. Apparatus and means according to claim 60 whereby vertical distribution of the resulting geometrically converted image is modified by re-imaging said converted image on a cylindrical easel having an axis which is perpendicular to the axis of said tilting easel, the axis of said cylindrical easel being parallel with the projected horizon of a horizontal panorama.

64. Apparatus and means according to claim 60, whereby geometric conversion of the image is accomplished by exposing photographic media through a slit that is combined with said tilting easel, said easel also having means to translate said photographic media under said slit, said easel being in optical communication with said photographic enlarger, said photographic enlarger also having a rotating carrier for the original annular image, whereby said annular image is rotated by said rotating carrier and is progressively exposed onto said photographic media through said slit, whereby the resulting 360 degree image and images extracted therefrom are continuous and seamless, said easel also having means to warp said photographic media and said slit in a direction that is perpendicular to the motion of said photographic media.

65. Apparatus and means according to claim 64, also associated with an image that is acquired with an optical system having more than hemispherical coverage, whereby said apparatus and means provide substantially undistorted 360 degree rectangular panoramas and images extracted therefrom.

66. Apparatus and means according to claim 60 also comprising a linear gradient neutral density filter to substantially compensate for the range of brightness due to differing lens to easel distances and the range of angles at which the light from the image source impinges on the easel, whereby the density resulting projected image is substantially constant, whereby the density of resulting print or film is substantially consistent.

67. Apparatus and means according to claim 60 also comprising active linear dodging and active color filtration means, said active filtration means being accomplished by registering appropriate color printing filters with a dodging mask in such a way that both said filters and said mask can be moved together, whereby the edges of said filters precede the leading edge of said dodging mask as said registered assembly is moved between said photographic enlarger and said easel;

said active filtration providing means to compensate for reciprocity failure in the photographic media resulting by the variable exposure time which is required due to the pronounced tilt of said easel, whereby the density and color rendition of a resulting print or film is substantial consistent.