Abstract:
An improved helmet is provided including means to telescopically acquire an image of a field of view, which comprises, a telescopic optical system including an objective lens mounted to said helmet above the line of sight of the wearer, a light-conducting fiber optics bundle mounted to said helmet for receiving the image from the objective lens, and collimating lens for receiving the image from the fiber optics bundle and projecting the image onto a helmet-mounted visor in the line of sight of the wearer. A shutter, remotely controllable by the wearer, may be disposed intermediate the objective lens and display to selectively block transmission of the image.
Abstract:
An improved system for measuring absolute angular deviation through transparencies, such as aircraft windscreens, uses an incoherent light source and a target configuration in the form of an opaque slide with a transparent "L"-shaped pattern. The positions of images of the legs of the "L" passed through the transparency are detected by CCD arrays for measurement of the azimuth and elevation components of angular deviation for each tested point on the transparency, uncontaminated by lateral displacement errors.
Abstract:
An apparatus for detecting contact between an object and the surface of a body, by utilizing various indices of refraction so that electromagnetic energy reaches a detector system only when there is optical contact. A body of transmissive material is irradiated with electromagnetic energy. That portion of the energy which enters the body through a first boundary surface is refracted, thereby striking the body surface leading to the detection system at angles of incidence sufficient to cause total reflection at that surface. Similarly, electromagnetic energy which passes through the body, strikes the object on the opposite side, and reenters the body is refracted upon reentry and totally reflected at the surface leading to the detector system. Contact between the object and the contact detecting surface produces diffusive reflection within the body at all points of actual contact. The incidence angle between the diffusive electromagnetic energy at each point of contact and the surface leading to the detection system is sufficiently low to permit passage of electromagnetic energy outward through surface and onto the detection system. Since the contact points and the detection system are geometrically related, contact locations or patterns may be recognized when they are being sought.
Abstract:
A quad-emissive display apparatus to provide suitable emissive energy in four spectral bands to provide simultaneous evaluation of sensors having different spectral sensitivities. The apparatus can simultaneously provide four spectral bands of visible (0.4 to 0.7 microns), near infrared (0.7 to 1.0 microns), short wave infrared (1.0 to 3.0 microns) and the long wave infrared (8.0 to 14.0 microns) radiation.
Abstract:
Device and method are described for measuring transmissivity and haze in transparencies as detected through night vision goggles, including an emitter portion and a sensor portion, the emitter portion including a first light source for presenting an image to the sensor portion through the transparency and a second light source for projecting a haze producing light onto the transparency, the sensor portion including a light intensifier tube and a photometer for measuring the luminance output of the light intensifier tube and quantifying attenuation (transmissivity) and haze (light scatter) characteristics of the transparency as viewed through night vision goggles.
Abstract:
A night vision device enhancement wherein occurrence of a bright object in an input scene of the night vision device is precluded from adversely affecting reproduction of adjacent low radiance level portions of the input scene. By optically limiting or excluding bright object input scene portions from the night vision device input field the disclosed system precludes both image intensifier-related effects, effects such as blooming and current saturation, and also precludes automatic gain control-related effects such as full-field sensitivity decrease based on the bright object. Plural embodiments of the system are disclosed, embodiments based on bright object attenuation by both yet to be developed photo active materials such as photochromics and embodiments which use present state of the art liquid crystal materials and accompanying electronics. Military and non-military uses of the improved night vision device are contemplated.
Abstract:
A system for measuring crazing in a transparency is described which comprises one or more light sources disposed near a first surface of the transparency for projecting light rays through the transparency at the portion thereof having a crazed condition, optical detectors corresponding in number to the number of light sources disposed on the opposite side of the transparency, each detector positioned to detect only light from a single corresponding source reflected from the crazed portion of the transparency, and a source of power for the sources and detectors. A sequencing circuit may be included to selectively activate selected light sources and corresponding optical detectors.
Abstract:
A monocular night vision apparatus employing an infrared energy spectrum source of illumination and a camera lens and night vision image intensifier combined receiver apparatus into a small hand-held portable package that is both low in cost and reliable in nature is described. The night vision transmitter apparatus includes a laser diode energy source that is coupled to an aperture controlled and focus controlled optical system and driven by an electronic closed-loop feedback energization circuit which employs self-contained battery sources of energy. Multiple operating modes and operating intensities of the light source are provided through a plurality of signal inputs to the closed feedback loop of the laser diode energy source. Disturbance of the closed feedback loop by reflected energy within the optical transmitter apparatus is precluded by the use of feedback prevention optical alignment in the transmitter's optical system.
Abstract:
A device for measuring optical transmissivity of a transparency is described which comprises a diffuse light source (Lambertian diffuser) of controllable substantially constant luminance and preselected light emitting surface area for placement near a first side of a transparency for transmitting diffuse light along an optical axis through the transparency, a housing having a wall defining an aperture for placement near the second side of the transparency opposite the diffuse light source, and a detector in the form of a photo diode, cadmium sulfide cell or the like disposed within the housing and coaxial with and spaced a preselected distance from the aperture, the aperture being selected in size to expose all of the effective light detection surface area of said detector to the light emitting surface area of the diffuse light source.
Abstract:
A method of measuring haze of an aircraft transparency includes producing a first reading representative of the level of light scattered by an area of a transparency under test while on the aircraft when it is illuminated by a known light source, and producing a second reading representative of the level of light scattered by a predetermined, preferably worst haze condition, reference plate when it is illuminated by the light source in place of the transparency. Then, a ratio of the first and second readings is calculated to provide a quantitative measure proportional to the degree of haze in the transparency test area.