GENERAL ASPHERE-CONIC CONFORMAL OPTICAL WINDOWS

• Main Authors: MILLS, JAMES, B, CROWTHER, BLAKE, G, MCKENNEY, DEAN, B, SPARROLD, SCOTT, W
• Format: Patent
• Language: English; French; German
• Published: 09.07.2003
• Edition: 7
• Subjects: AIMING; ANALOGOUS ARRANGEMENTS USING OTHER WAVES; BLASTING; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; HEATING; LIGHTING; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION ORRERADIATION OF RADIO WAVES; MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; MECHANICAL ENGINEERING; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS; RADIO DIRECTION-FINDING; RADIO NAVIGATION; TESTING; WEAPON SIGHTS; WEAPONS

An optical system includes a window made of a curved piece of a transparent material having an inner surface and an outer surface. The inner surface has a nominal inner surface shape defined by a first conicoidal relationship, and the outer surface has a nominal general aspheric surface shape. The optical system also typically includes a sensor and an optical train on the side of the inner surface of the window. The accuracy of the shape of the inner surface is tested by directing a coherent light beam through a remote focus of the inner surface, reflecting the light beam from the inner surface toward an adjacent focus of the inner surface, reflecting the light beam from a spherical reflector at the adjacent focus of the inner surface and back toward the inner surface, reflecting the light beam from the inner surface back toward the remote focus, and interferometrically comparing the reflected beam arriving at the remote focus with a reference beam.