Unit power imaging catoptric anastigmat

Claim 2

A unity magnification catoptric image-forming system comprising at least one concave mirror and at least one convex mirror, said mirrors being supported with their centers of curvature substantially coincident, and means to define a location for an object the image of which after at least three reflections including at least one reflection at each of said mirrors is a real image at a second location, the sum of the powers of said convex mirrors multiplied by the numbers of reflections thereat respectively being sufficiently less than the sum of the powers of said concave mirrors multiplied by the numbers of reflections thereat respectively to produce at said second location a stigmatic image of an object in said first location.

Claim 3

An image-forming system according to claim 1 wherein the image at said second location includes third order tangential field curvature of one sense and higher order tangential field curvature of opposite sense.

Claim 4

A unity magnification catoptric image-forming system comprising a concave spherical mirror and a convex spherical mirror, said mirrors being supported with their centers of curvature substantially coincident, and means to define a location for an object the image of which in said concave mirror is a real image at a second location, said convex mirror being positioned about said center of curvature to reflect to said concave mirror light from said object location initially reflected to said convex mirror from said concave mirror, thereby light from said object location will be reflected at least twice at said concave mirror an: at least once at said convex mirror before being focused at said second location, the power of said convex mirror multiplied by the number of reflections thereat being sufficiently less than the power of said concave mirror multiplied by the number of reflections thereat to produce at said second location a stigmatic image of an object in said first location.

Claim 5

A unity magnification catoptric image-forming system comprising a concave spherical mirror and a convex spherical mirror, said mirrors being supported with their centers of curvature substantially coincident, and means to define a location for an object the image of which in said concave mirror is a real image at a second location, said convex mirror being positioned about said center of curvature to reflect to said concave mirror light from said object location initially reflected to said convex mirror from said concave mirror, thereby light from said object location will be reflected at least twice at said concave mirror an: at least once at said convex mirror before being focused at said second location, the power of said convex mirror multiplied by the number of reflections thereat being sufficiently less than the power of said concave mirror multiplied by the number of reflections thereat to produce at said second location a stigmatic image of an object in said first location.

Claim 6

An image-forming system according to claim 3 wherein the focused image at said second location includes third order tangential field curvature of one sense and higher order tangential field curvature of opposite sense.

Claim 7

A unity magnification catoptric image-forming system comprising a concave spherical mirror and a convex spherical mirror supported with their centers of curvature substantially coincident, and means to define in a plane containing said centers of curvature an object location the image of which in said concave mirror is a real image at a second location in said plane, said convex mirror having a radius of curvature substantially equal to one-half the radius of said concave mirror increased by the square of the distance in said plane from said centers to said object location divided by four times the radius of the concave mirror, said convex mirror being positioned with respect to said concave mirror to reflect to the concave mirror light diverging from said object location initially reflected to said convex mirror from said concave mirror whereby light from said object location will be reflected twice at said concave mirror and once at said convex mirror before being focused at said second location.

Claim 8

A unity magnification catoptric image-forming system comprising a concave spherical mirror and a convex spherical mirror supported with their centers of curvature substantially coincident, and means to define in a plane containing said centers of curvature an object location the image of which in said concave mirror is a real image at a second location in said plane, said convex mirror having a radius of curvature substantially equal to one-half the radius of said concave mirror increased by the square of the distance in said plane from said centers to said object location divided by four times the radius of the concave mirror, said convex mirror being positioned with respect to said concave mirror to reflect to the concave mirror light diverging from said object location initially reflected to said convex mirror from said concave mirror whereby light from said object location will be reflected twice at said concave mirror and once at said convex mirror before being focused at said second location.

Claim 9

An image-forming system according to claim 5 wheRein said defining means include at least one plane mirror, said system including at least one additional plane mirror disposed between the last reflection at said concave mirror and said second location, the sum of the inclinations of said plane mirrors to the normal to said plane amounting substantially to 180*.

Claim 10

The image-forming system of claim 5 wherein said defining means include an arcuate slit of radius substantially equal to the distance of said object location from said centers of curvature.

Claim 11

A unity magnification catoptric image-forming system comprising a concave spherical mirror and a convex spherical mirror supported with their centers of curvature substantially coincident, and means to define in a plane containing said centers of curvature an object location the image of which in said concave mirror is a real image at a second location in said plane, said convex mirror having a radius of curvature substantially equal to one-half the radius of said concave mirror increased by an amount substantially equal to the third order longitudinal spherical aberration of said concave mirror for a ray from said object location perpendicular to said plane, said convex mirror being positioned with respect to said concave mirror to reflect to the concave mirror light diverging from said object location initially reflected to said convex mirror from said concave mirror whereby light from said object location will be reflected twice at said concave mirror and once at said convex mirror before being focused at said second location.

Claim 12

A unity magnification catoptric image-forming system comprising a concave spherical mirror and a convex spherical mirror supported with their centers of curvature substantially coincident, and means to define in a plane containing said centers of curvature an object location the image of which in said concave mirror is a real image at a second location in said plane, said convex mirror having a radius of curvature substantially equal to one-half the radius of said concave mirror increased by an amount substantially equal to the third order longitudinal spherical aberration of said concave mirror for a ray from said object location perpendicular to said plane, said convex mirror being positioned with respect to said concave mirror to reflect to the concave mirror light diverging from said object location initially reflected to said convex mirror from said concave mirror whereby light from said object location will be reflected twice at said concave mirror and once at said convex mirror before being focused at said second location.

Claim 13

A unity magnification catoptric image-forming system comprising a concave mirror and a convex mirror, said mirrors being supported with their centers of curvature substantially coincident, means to define in a plane containing said centers a location for an object the image of which in said concave mirror is a real image at a second location in said plane, said convex mirror being positioned about said centers to reflect to said concave mirror light from said object location initially reflected to said convex mirror from said concave mirror, whereby light from said object location will be reflected at least twice at said concave mirror and at least once at said convex mirror before being focused at said second location, and a second concave mirror positioned on the side of said plane opposite said first-named convex and concave mirrors to refocus light diverging from said second location, the power of said convex mirror multiplied by the number of reflections thereat being sufficiently less than the sum of the powers of said concave mirrors multiplied by the numbers of reflections thereat respectively to produce at the image of said second location in said second concave mirror a stigmatic image of an object in said first location.

Claim 14

A unity magnification catoptric image-forming system comprising a concave mirror and a convex mirror, said mirrors being supported with their centers of curvature substantially coincident, means to define in a plane containing said centers a location for an object the image of which in said concave mirror is a real image at a second location in said plane, said convex mirror being positioned about said centers to reflect to said concave mirror light from said object location initially reflected to said convex mirror from said concave mirror, whereby light from said object location will be reflected at least twice at said concave mirror and at least once at said convex mirror before being focused at said second location, and a second concave mirror positioned on the side of said plane opposite said first-named convex and concave mirrors to refocus light diverging from said second location, the power of said convex mirror multiplied by the number of reflections thereat being sufficiently less than the sum of the powers of said concave mirrors multiplied by the numbers of reflections thereat respectively to produce at the image of said second location in said second concave mirror a stigmatic image of an object in said first location.

Claim 15

A unity magnification catoptric image-forming system comprising at least one convex mirror and at least two concave mirrors, said mirrors being supported with their centers of curvature substantially coincident, at least one of said convex mirrors and at least one of said concave mirrors being disposed on one side of a plane containing said centers of curvature, at least one other of said concave mirrors being disposed on the other side of said plane, those of said convex and concave mirrors on said one side of said plane being positioned to form upon successive reflections thereat including at least two reflections at said one concave mirror and at least one reflection at said one convex mirror an image in said plane of an object in said plane, which image is reimaged at a separate location in said plane by reflections at those of said mirrors on the other side of said plane, the sum of the powers of said convex mirrors multiplied by the number of reflections thereat respectively being substantially equal to the sum of the powers of said concave mirrors multiplied by the numbers of reflections thereat respectively.

Claim 16

A unity magnification catoptric image-forming system comprising at least one convex mirror and at least two concave mirrors, said mirrors being supported with their centers of curvature substantially coincident, at least one of said convex mirrors and at least one of said concave mirrors being disposed on one side of a plane containing said centers of curvature, at least one other of said concave mirrors being disposed on the other side of said plane, those of said convex and concave mirrors on said one side of said plane being positioned to form upon successive reflections thereat including at least two reflections at said one concave mirror and at least one reflection at said one convex mirror an image in said plane of an object in said plane, which image is reimaged at a separate location in said plane by reflections at those of said mirrors on the other side of said plane, the sum of the powers of said convex mirrors multiplied by the number of reflections thereat respectively being substantially equal to the sum of the powers of said concave mirrors multiplied by the numbers of reflections thereat respectively.