Abstract:
A hot spot filter for a light guide is created by taking an image of the light output pattern of an illuminated light guide. The hot spot filter may be a film, a layer, or an additional liquid crystal display dedicated to attenuating bright spots from the light guide. The hot spot filter may be incorporated into the image display by adjusting the grey scale of individual pixels to provide sufficient compensation.
Abstract:
A hot spot filter for a light guide is created by taking an image of the light output pattern of an illuminated light guide. The hot spot filter may be a film, a layer, or an additional liquid crystal display dedicated to attenuating bright spots from the light guide. The hot spot filter may be incorporated into the image display by adjusting the grey scale of individual pixels to provide sufficient compensation.
Abstract:
An auto darkening eye protection device comprising a shutter assembly and a control circuit. The shutter assembly is adjustable between a light state and a dark state. The control circuit comprises a sensing circuit, a weld detect circuit, a positive voltage generator, and a negative voltage generator. The sensing circuit senses incident light and provides an output indicative of the incident light. The weld detect circuit receives the output of the sensing circuit, and enables a dark state drive signal to be delivered to the shutter assembly. The positive and negative voltage generators output the dark state drive signal to the shutter assembly to switch the shutter assembly from the light state to the dark state upon enablement by the weld detect circuit. The dark state drive signal includes a high voltage pulse followed by a stable AC waveform. The high voltage pulse is formed by a positive voltage signal and a negative voltage signal.
Abstract:
A hot spot filter for a light guide is created by taking an image of the light output pattern of an illuminated light guide. The hot spot filter may be a film, a layer, or an additional liquid crystal display dedicated to attenuating bright spots from the light guide. The hot spot filter may be incorporated into the image display by adjusting the grey scale of individual pixels to provide sufficient compensation.
Abstract:
A polarization control system includes a beam source that generates a first beam component containing light with a first polarization and a first frequency and a second beam component containing light with a second polarization and a second frequency. A polarization state modulator adjusts the polarizations of the components for transmission on a single optical fiber. A detector system measures polarizations of the components when output from the optical fiber and determines how to adjust the polarization state modulator in order to give the first and the second components the desired output polarization states. The beam source can be implemented using a Zeeman-split laser, a laser containing a birefringent element, a pair of phase-locked lasers, and/or a variety of configurations of electro-optic or acousto-optic crystals operated to create or enhance the frequency difference between the beam components.
Abstract:
A vehicle rearview mirror system includes an electro-optic reflective element, an ambient light sensor that is operable to sense ambient light, a glare light sensor that is operable to sense glare light and a circuit that is responsive to the ambient glare light sensors which establishes a reflectance level of the reflective element. The circuit includes a sensor-responsive device and a controller. The sensor-responsive device produces an output that is a function of light sensed by glare and ambient light sensors. The controller connects one of the glare and ambient light sensors at a time with the sensor-responsive device to establish glare and ambient light levels and thereby the reflectance level of the reflective element. The mirror system may include a display operable to project light through the reflective element and may control the intensity of the display as a function of the glare light and ambient light.
Abstract:
A light processor (such as a spectrometer) providing wavelength equalization for a sample pathway and a reference pathway by actuation of a light amplitude modulator. A chemometric processor including a light amplitude modulator capable of performing chemical analysis by applying weights to wavelengths of light, thereby reducing the need for electronic post processing.
Abstract:
An imaging or viewing system, which automatically compensates for bright spots, which tend to overload or saturate imaging system. The system can be used with imaging type tracking systems, viewers and various types of optical devices which heretofore have been unable to provide satisfactory performance due to saturation or overloading of an imaging device due to bright spots, i.e., laser radiation flares or sunlight. The system in accordance with the invention is configured such that reflected radiation is imaged onto a first image plane without dividing the incoming radiation into two optical paths. A digital mirror device, i.e., is disposed at the first image plane. The radiation level of each pixel in the image plane is compared with a fixed threshold on a pixel by pixel basis and used to generate a mirror drive signal that automatically reduces the reflectivity of the corresponding mirror pixel to compensate for bright spots.
Abstract:
The invention is an instrument for sensing the state of polarization (SOP), and for transforming the SOP of a beam of light from an incident continuously-varying arbitrary SOP to a desired exit SOP, using a polarization compensator under feedback control. A polarization sensor uses two or three samples of a beam to sense the Poincare sphere latitude and longitude error in SOP. A polarization controller adjusts the SOP of light, which is then sensed by the polarization sensor, which develops signals to drive the polarization compensator using feedback methods. Unlike prior-art systems, the feedback seeks a mid-point rather than an extremum in the sensed signals, so there is no sign ambiguity in the feedback control. Further, the sensor signals indicate orthogonal displacements in SOP that correspond to specific elements in the polarization controller, so there is no ambiguity as to which element needs adjustment in order to correct a given error in SOP. The result is a high-performance instrument with high-speed response to changes in the SOP of the incident beam, and very low error in the exit SOP.
Abstract:
Radiation receiver with a photodetector and a sensor, wherein the sensor receives the radiation intensity, and a shutter arranged before the photodetector is driven in dependence on the detected incident radiation intensity. The incident radiation is supplied to the photodetector via a delay device arranged before the shutter, so that no radiation destroying the photodetector can reach the photodetector, due to the shutter having been driven, and can if necessary be kept away or absorbed by the shutter.