Method for operating a panoramic optical system

• US 4,326,775 A
• Filed: 06/09/1980
• Issued: 04/27/1982
• Est. Priority Date: 02/07/1979
• Status: Expired due to Term

• Current Assignee: Don G. King
• Original Assignee: Don G. King
• Inventors: King, Don G.
• Primary Examiner(s): Henry, Jon W.
• Application Number:
  US06/157,865
• Time in Patent Office: 687 Days
• Field of Search: 350/320, 350/293, 350/441, 350/442, 350/21, 350/27, 354/95
• US Class Current: 359/725
• CPC Class Codes: G02B 13/06 Panoramic objectives; So-called "sky lenses" including panoramic objectives having reflecting surfaces
• CPC Class Codes: G03B 37/06 involving anamorphosis G03B37/02, G03B37/04 take precedence
• CPC Class Codes: Y10S 359/90 Methods

Abstract

A method for operating a panoramic optical system to produce a shadow or darkened zone on the apex of a curved lens in order to eliminate undesirable optical interference in the region between the curved reflector and the focal plane is disclosed. The claimed method makes possible the accurate prediction of the diameter of the darkened zone around which the reflected image is annularly disposed, for a lens having a reflective surface of a given radius of curvature and for a specific location of the transparent/opaque border relative to the top of the lens. This makes possible the calibration of vertical displacement of an opaque sleeve for quickly and easily establishing a setting which will produce a darkened zone of a standard diameter.

Claims

1. A method for operating a panoramic optical system of the type for recording images disposed substantially 360°

around the system onto a film plane, said method comprising the steps;

(a) spacing the top of a curved lens from said film plane at a distance i, said lens having a base portion and a curved outer surface of light reflective material of diameter b and radius of curvature r between its top and base, said curved surface being symmetrical about an axis which extends transversely to the film plane, and an origin of curvature p located at a distance x with respect to said axis and at a distance y with respect to the top of said lens, the axis of said curved surface being substantially perpendicular to said film plane;

(b) enclosing the space between the base of said curved lens and said film plane with a sleeve, said sleeve having a transparent zone for enabling light rays from the outside of said sleeve to impinge upon the outer surface of said curved lens and an opaque zone contiguous with the transparent zone for preventing said light rays from impinging upon a predetermined area at the base portion of said lens; and

,

(c) positioning the border defined by the transparent/opaque zones of said sleeve at a distance h below the top of said lens wherein

h=r sin (α

)-y

where

r=the radius of curvature of the curved surface 13 at the boundary of zone 20

r_b =r cos (α

)-x

p=origin or curvature of the curved surface 13 at the boundary of zone 20

x, y=coordinates of p ##EQU3## α

=arc tan y/x ##EQU4## b=diameter of reflector lens top surface i=vertical distance from top of reflector lens to film plane 12.