Panoramic lens

• US 4,484,801 A
• Filed: 09/20/1982
• Issued: 11/27/1984
• Est. Priority Date: 09/20/1982
• Status: Expired due to Fees

• Current Assignee: the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Cox, Arthur
• Primary Examiner(s): Corbin, John K.
• Assistant Examiner(s): Gass, Rebecca D.
• Application Number:
  US06/420,451
• Time in Patent Office: 799 Days
• Field of Search: 350/441
• US Class Current: 359/725
• CPC Class Codes: G02B 13/06 Panoramic objectives; So-called "sky lenses" including panoramic objectives having reflecting surfaces

Abstract

A panoramic lens grouping utilizes a number of negative and positive powerenses to provide 360° photography and projection capabilities. The lens grouping uses a hyperbolic mirror as its input or output, in the photographic or projection mode, respectively. The lenses of the group are selected to reduce the Petzval curvature introduced by the hyperbolic mirror. The lenses are arranged such that the negative power lenses are flanked by the positive power lenses. Provision is made for the use of an internal shutter in the spacing between lenses in the lens group.

Claims

1. An optical system for 360°

annular image transfer comprising;

a hyperbolically surfaced mirror having a near and far focal point and an apex at which is located a central aperture;

a plane mirror having its surface perpendicular to the optical axis of said hyperbolically surfaced mirror;

an envelope of optically suitable transparent material having an outer and inner surface generated in symmetry from said near focal point of said hyperbolically surfaced mirror and attached to said hyperbolically surfaced mirror and said plane mirror to hold the same in spaced axial symmetry;

a refractive lens system of negative lens elements flanked by positive lens elements;

said hyperbolically surfaced mirror and said plane mirror and said lens system constituting a total optical system having an entrance pupil; and

said mirrors being faced with the mirrored surfaces toward each other and held in a spaced relationship by said envelope such that said entrance pupil of said total optical system coincides with the near focal point of said hyperbolically surfaced mirror.

2. The optical system of claim 1, wherein said refractive lens system comprises:

a first lens group having a plurality of negative and positive lens elements;

a second lens group having a plurality of negative and positive lens elements; and

means for housing said lens groups in fixed spatial relationship to one another such that they are proximate one another along the optical axis.

3. The optical system of claim 2, further comprising shutter means secured to said housing means in fixed relationship between said lens groups.

4. The optical system of claim 3, wherein said first lens group comprises:

a first lens of positive refracting power centered on said optical axis and held within said aperture of said hyperbolically surfaced mirror by said housing means;

a second lens of positive refracting power centered on said optical axis and held in fixed relation to said first lens by said housing means;

a third lens of positive refracting power centered on said optical axis and held in fixed relation to said second lens;

a fourth lens of positive refracting power centered on said optical axis and held in fixed relation to said third lens;

a fifth lens of negative refracting power centered on said optical axis and held in fixed relation to said fourth lens; and

a sixth lens of negative refracting power centered on said optical axis and held in place by said housing.

5. The optical system of claim 4, wherein said second lens group comprises:

a seventh lens of negative refracting power centered on said optical axis proximate said sixth lens fixedly held by said housing means;

an eighth lens of negative refracting power centered on said optical axis and held proximate said seventh lens by said housing means;

a ninth lens of positive refracting power centered on said optical axis and held proximate said eighth lens by said housing means;

a tenth lens of positive refracting power centered on said optical axis and held proximate said ninth lens by said housing means;

an eleventh lens of positive refracting power centered on said optical axis and held proximate said tenth lens by said housing means; and

a twelfth lens of positive refractive power centered on said optical axis and held proximate said eleventh lens by said housing means.

6. The optical system of claim 1, wherein said negative lens elements are made of optical quality fused silica.