Abstract: The present invention is directed to a method and apparatus for adjusting the viewing angle of a liquid crystal display. In a preferred embodiment of the present invention, a plurality of digital-to-analog converters are arranged in pairs which have a fixed relationship. By determining appropriate values for the digital-to-analog converters, a desired viewing angle may be obtained for a liquid crystal display.

Abstract: The invention describes a method for electronically adjusting the viewing angle of a liquid crystal display within a panel fixed in location by the structure within which it is located, such as an electronic flight indicator unit. The adjustment in viewing angle is achieved by changing the bias voltage to alter the pre-tilt angle of the liquid crystal layer.

Abstract: The present invention is directed to a method and apparatus which utilizes a software-based digital signal processing circuit to generate a signal which is representative of the status of a movable component. A preferred embodiment of the apparatus of the present invention includes a synchro which is connected to a movable component. An analog reference excitation may be applied to the synchro, and the synchro generates analog synchro signals which bear a relationship to the status of the movable component. The analog synchro signals are converted to digital synchro signals by a plurality of analog-to-digital converters. A digital reference signal and the digital synchro signals are provided to a software-based digital signal processing circuit which preferably corrects constant and time-varying errors in the digital synchro signals and generates a status signal which is representative of the status of the movable component.

Abstract: The present invention is a method and apparatus for capping and grounding an electrical connector to prevent leakage of electromagnetic interference into or out of a chassis for a piece of electronic equipment. In a preferred embodiment of the present invention, a chassis panel has a conductive area that may serve as chassis ground. The electrical connector is secured to the chassis panel, and it is disposed over a penetration in the chassis panel. The electrical connector has a conductive shell that is electrically tied to chassis ground. An EMI plate caps the electrical connector, and it is also electrically tied to chassis ground. The EMI plate permits the transmission of desired signals into and out of the chassis via the electrical connector and associated conductors while substantially preventing leakage of electromagnetic interference through the electrical connector.

Abstract: The present invention is directed to a method and apparatus which utilizes a software-based digital signal processing circuit to generate a signal which is representative of the status of a movable component. A preferred embodiment of the apparatus of the present invention includes a synchro which is connected to a movable component. An analog reference excitation may be applied to the synchro, and the synchro generates analog synchro signals which bear a relationship to the status of the movable component. The analog synchro signals are converted to digital synchro signals by a plurality of analog-to-digital converters. A digital reference signal and the digital synchro signals are provided to a software-based digital signal processing circuit which preferably corrects constant and time-varying errors in the digital synchro signals and generates a status signal which is representative of the status of the movable component.

Abstract: A liquid crystal display flight indicator unit having the capability to display a horizontal situation indicator (HSI) or an attitude direction indicator (ADI) on the viewing area of the same unit. Signals from existing aircraft electronics are processed to determine whether the incoming signal is an HSI or ADI graphical image to be displayed on the viewing area. A unique component layout is described to enable HSI and ADI to be contained within a unit having a chassis size not larger than previously known HSI and ADI units.

Abstract: The invention describes a method for electronically adjusting the viewing angle of a liquid crystal display within a panel fixed in location by the structure within which it is located, such as an electronic flight indicator unit. The adjustment in viewing angle is achieved by changing the bias voltage to alter the pre-tilt angle of the liquid crystal layer.

Abstract: A liquid crystal display flight indicator unit having the capability to display a horizontal situation indicator (HSI) or an attitude direction indicator (ADI) on the viewing area of the same unit. Signals from existing aircraft electronics are processed to determine whether the incoming signal is an HSI or ADI graphical image to be displayed on the viewing area. A unique component layout is described to enable HSI and ADI to be contained within a unit having a chassis size not larger than previously known HSI and ADI units.

Abstract: A method is provided in which a relatively cold lamp filament may be turned on for a brief period of time, then turned off, then turned on again, then off again, and this process repeated for successively longer periods of on time, until eventually the filament power is left on continuously. This "pulse starting" may be controlled by a programmable microcontroller in association with a power supply to the lamp filament. The result is a longer lasting lamp filament.

Abstract: Described is a backlighting module that may be used in an electronic liquid crystal display device. The backlighting includes one or more lamps within a cavity of the module. The lamps are capable of a wide range of luminance including low-level luminance achieved by a unique burst modulation scheme for driving the lamps.

Abstract: An improved system for continuously detecting and correcting the display in a cathode ray tube for errors in size and linearity. The system employs a crystal oscillator as a reference frequency to determine absolute error which is represented as "size" on the display screen, and relative error which is represented as linearity. The error is determined from the index pulse feedback, which is an output of a phase lock loop voltage controlled oscillator which is compared to the reference frequency to provide an error voltage level. This output level is then digitized and processed in terms of general control, interpolation, extrapolation, filtering, etc., testing, and stored in digital memory. The digital error data is converted back to analog levels for insertion into a horizontal auxiliary amplifier circuit for linearity correction. A main horizontal amplifier circuit receives size correction.

Abstract: An automotive accessory control system provides a single, centralized electronic control circuit for automatic switching of exterior lighting, intermittent windshield wiper operation, electric window defogger control and instrument panel lighting control.