A dispersive spectrometer comprising a primary lens that images a scene onto a slit through which light from a thin portion of the scene passes to a collimating lens. A grism is optically coupled to the collimating lens. The grism includes a diffractive element and is disposed such that light from the thin portion of the scene has an angle of incidence upon the diffractive element that is greater than one-third of the critical angle at the surface of the grism. The diffractive element disperses ...

Coherent light from a laser is directed through first and second two dimensional planar arrays of lenslets which are moved relative to each other to enable the beam to point along any diffraction order, and fine pointing of the beam between orders is accomplished by slightly changing the angle of incidence of the beam with respect to the arrays. The laser is replaced by a photoreceptor when the scanner operates as a light beam receiver.

A beam director for an optical ranging system for measuring relative distance changes between first and second retroreflectors in which a beam of radiation is introduced between the first and second retroreflectors by a steering beam splitter pellicle positioned obliquely therebetween. A portion of the beam is reflected by the pellicle onto the first retroreflector, which reflects it back through the pellicle onto the second retroreflector, which in turn reflects it back onto the pellicle where ...

An array of a large number of low quality light collectors measure light generated by arrays of coherent light illuminators and rebounded from a target. The resulting data is utilized to derive the resulting speckle pattern which in turn is Fourier transformed to reconstruct the target image.

A birefringent spectral filter comprises a first birefringent stage and a polarizing beam splitter optically coupled to the first birefringent stage. The first birefringent stage is adapted to generate an optical path difference between light propagating along each of two orthogonal axes. This configuration is most advantageous when light incident on the first birefringent stage is polarized at 45.degree. relative to the extraordinary axis of the birefringent material. The first birefringent sta...

An optical alignment apparatus comprising a plurality of subapertures and a plurality of detectors. The subapertures are optically coupled to a reflective surface which formed by a plurality of adjustable reflective segments. Each subaperture falls within one of two subsets. The first subset includes those subapertures that are positioned to receive light reflected from a single reflective segment. The second subset includes those subapertures that are positioned to receive light reflected acros...

A microscope, not employing conventional optical elements, is disclosed wherein a sample under examination is subjected to a moving pattern of illumination having alternate light and dark interference fringes, and having a spatial frequency which varies during the motion of the fringes over the sample in a first direction, in order to obtain the sine components of the optical image of the sample. The light reflected off of the sample is gathered by a wide angle light detector to produce electric...

A test target for adaptive optics comprising, in the preferred embodiment, a plurality of nine adjacent, stacked, and aligned rows of a multiplicity of alternate opaque sections and transparent sections in a repeating bar pattern, with all sections being positioned on a flat transparent medium (such as film or glass), and with each opaque section being an opaque bar and with each transparent section being a transparent bar. Each row has a different spatial frequency than any other of the nine ro...

A system for determining the position of an object in which a moving periodic pattern is projected onto the object. A sensor on the object generates a sensor signal related to the periodic pattern. A reference signal is generated relating to the position of the moving periodic pattern. The sensor signal and the reference signal are compared to determine the position of the object. The pattern may be generated by projecting light through two gratings which are separated and have the same pattern....

A target is illuminated through an optically distorting region, such as atmospheric turbulence or non-precision optics, by coherent light and a first set of data is recorded indicative of the complex amplitude of scattered radiation and such target is thereafter illuminated by incoherent light to produce a second set of data indicative of the nature of the region; the second set is divided into the first set, and the resulting data is Fourier-transformed to produce a diffraction-limited target i...