A raster output scanner in which a twisted nematic liquid crystal is disposed in the path of the linearly polarized scanning beam incident on the scanner modulator to provide controlled rotation of the plane of polarization of the beam to maximize modulator diffraction efficiency and beam intensity, control over the crystal external electric field being either exercised manually or automatically, the latter through a feedback loop using a photodetector to monitor changes in beam intensity at the scanner photoreceptor. In an alternate embodiment, the liquid crystal is replaced by a magneto-optic cell.

An imaging apparatus for permitting night vision training by simulating night vision viewing during daylight operation. A cylindrical imaging device includes an objective lens and an ocular lens. Light from the objective lens passes through a filter and is inverter by a fiber optic inverter. A pair of liquid crystals receive the inverted image and pass the same to the ocular lens for viewing by the user. A plurality of lamps are positioned for impinging light on the second liquid crystal under electronic control. The pair of liquid crystals are controlled electronically for simulating night vision photomultiplier viewing. A pair of such imaging tubes are mounted in a training helmet together with under-goggle viewing areas and peripheral viewing areas in which liquid crystals are separately placed and are separately controllable in accordance with sensed light levels. An instructor pilot uses a microprocessor based controller for controlling each of the six liquid crystals.

Time sequential information is written to a first light-to-light conversion element, and the thus-written time sequential information is thereafter written from the first light-to-light conversion element to a second light-to-light conversion element in the form of two-dimensional information. With this arrangement, the time sequential information can be converted with high resolution to the two-dimensional information in real time operation without involving a brightness gradient or shading.

A bistable optical device integrated onto a semiconductor chip with a photoresponsive element receiving an input light signal and connected electrically to a photo emitting element so that the reverse current produced in the photoresponsive element by the input light signal causes light emission which is incident upon the photoresponsive element to increase reverse current by positive feedback, resulting in change from a low to high light output at a first change value of input light and a high to low output at a second and lower change value. A light modulator is formed between the elements to receive an input light signal and vary the amount of light received by the photoresponsive element from the photo emitting device and hence the change values.

An apparatus comprising an optical filter which resolves electromagnetic radiation into a sequence of resolved polarization components. The apparatus is also comprised of an imaging device having a storage device. The imaging device is disposed adjacent to the optical filter to receive the sequence of resolved polarization components from the optical filter and store them in the storage device for subsequent processing. The present invention pertains to an apparatus for viewing. The apparatus comprises a frame. The apparatus also is comprised of a first optical filter mounted on the frame to cover one eye of a viewer when the viewer wears the frame. The first optical filter resolves electromagnetic radiation into a sequence of resolved polarization components so the viewer can view the sequence of resolved polarization components. The present invention also pertains to an apparatus for viewing. The apparatus is comprised of a housing. The apparatus also includes at least a first lens disposed in the housing through which a viewer looks to aid vision of the viewer. The apparatus is also comprised of a first optical filter attached to the housing and adjacent the lens so light passing through the lens essentially passes through the first optical filter. The first optical filter resolves electromagnetic radiation into a sequence of resolved polarization components so the viewer can view the sequence of resolved polarization components. The present invention also pertains to a method for interpreting a scene.