Abstract: There is disclosed a ring field relay optical system incorporating concave spherical mirrors and including magnification achieved, at least partially, by a convex spherical mirror. In further modifications, aberrations introduced by the convex mirror are controlled by lens groups formed from fused silica. The system is usable from the visible through the deep ultraviolet portion of the spectrum.

Abstract: An optical system for illuminating an arcuate field efficiently and uniformly using a short arc source. A first light source having a length along its axis of symmetry emits light with angular uniformity 360.degree. in azimuth about its axis of symmetry. This light is divided into a plurality of sections of equal angular extent in azimuth and recombined to form adjacent secondary light sources while preserving the uniformity of angular uniformity in each section and simultaneously orienting the sections of light about parallel remote from the first source of light which has a length axes in each section. This forms a second source of light equal to the sum of the lengths of the secondary sources of light with uniform angular distribution over an angular extent of nearly 360.degree. divided by the number of the secondary light sources. By appropriate selection of parameters the difference in the numerical apertures of the illuminated arcuate field is selectable.

Abstract: Described is a method and apparatus for adjustment of an image-forming optical system to correct for manufacturing and assembly defects by providing a pair of refractive elements symmetrically disposed about the image plane or conjugate image plane of the system and mounted for translation and/or rotation about one or more of three orthogonal axes.

Abstract: This invention provides, in a restricted off-axis field optical system having a broad spectral range, which includes refracting elements, the improvement comprising:an optical system constructed and arranged so that the Petzval sum is substantially zero, said refracting elements including elements for balancing the effects of the variation in the Petzval sum due to variation in color by introducing axial chromatic aberration of the opposite sense so that the position of focus at the off-axis field remains substantially constant;according to the invention in one form thereof, the elements for balancing the effects of the variation in the Petzval sum due to variation in color include a symmetrically disposed nearly concentric meniscus element whose convex radius is larger than its concave radius and whose thickness is greater than the difference between its convex and concave radii;further, according to a form of the invention, the system includes at least one convex and one concave mirror, said mirrors being n

Abstract: An optical system for insertion into projection apparatus to permit viewing an image projected on an image plane without affecting its quality, size or position, including a beam-splitting element disposed in the optical path before the image plane which will transmit the radiation to the image plane and reflect a portion of the radiation reflected from the image plane in a direction which permits viewing, optical elements disposed in the optical path to correct for image displacement and aberrations caused by the beam-splitting element, said optical system being of unit power; according to one aspect of the invention the system is afocal so that it will remain at unit power when it is shifted longitudinally and the image position is insensitive to longitudinal displacement; and according to another aspect of the invention each element of the system is afocal so that the system remains at unit power and insensitive to changes in spacing between the elements.

Abstract: This invention relates to a system for illuminating an annular field disposed about an axis characterized by an arcuate source of radiation disposed concentrically about the axis, and an annular field imaging system having an axis of symmetry coincident with said axis for forming an image of the arcuate source on the annular field.

Abstract: A unity magnification catoptric image-forming system and an illumination system on the one hand, and an object- and image-surface supporting means on the other hand, are arranged for relative movement to retain the object and image surfaces in unity magnification conjugate planes of the catoptric system while effecting a scanning-type exposure of successive portions of the image surface to successively illuminated portions of the object. Fine motion mechanisms permit accurate preliminary adjustment of the object- and image-receiving surfaces relative to each other while under visual examination with the aid of the catoptric image-forming system.

Abstract: A unity magnification catoptric image-forming system and an illumination system on the one hand, and an object- and image-surface supporting means on the other hand, are arranged for relative movement to retain the object and image surfaces in unity magnification conjugate planes of the catoptric system while effecting a scanning-type exposure of successive portions of the image surface to successively illuminated portions of the object. Fine motion mechanisms permit accurate preliminary adjustment of the object- and image-receiving surfaces relative to each other while under visual examination with the aid of the catoptric image-forming system.