Abstract: The chassis of a spacecraft has one side exposed to ultraviolet photons and another side shielded from the ultraviolet photons. An electrically conductive surface is disposed on the exposed side of the chassis and is electrically isolated from the chassis. A field-emission array device has a gate, an emitter array, a first terminal electrically connected to the gate, and a second terminal electrically connected to the emitter array. The first terminal electrically couples the gate to the electrically conductive surface on the exposed side of the chassis, and the second terminal electrically couples the emitter array to a surface on the shielded side of the chassis. The emitter array discharges electrons from the surface on the shielded side when a voltage difference in excess of a threshold voltage develops between the gate and the emitter array because of differential charging of the exposed and shielded sides of the chassis.

Abstract: The chassis of a spacecraft has one side exposed to ultraviolet photons and another side shielded from the ultraviolet photons. An electrically conductive surface is disposed on the exposed side of the chassis and is electrically isolated from the chassis. A field-emission array device has a gate, an emitter array, a first terminal electrically connected to the gate, and a second terminal electrically connected to the emitter array. The first terminal electrically couples the gate to the electrically conductive surface on the exposed side of the chassis, and the second terminal electrically couples the emitter array to a surface on the shielded side of the chassis. The emitter array discharges electrons from the surface on the shielded side when a voltage difference in excess of a threshold voltage develops between the gate and the emitter array because of differential charging of the exposed and shielded sides of the chassis.

Abstract: Described are a system and method for monitoring and characterizing a stimulus in order to detect transient phenomena. An analog signal represents the stimulus. Conversion circuitry receives the analog signal and continuously converts the analog signal into digital data. Digital circuitry continuously receives the digital data from the conversion circuitry and dynamically computes from the digital data a value that characterizes a parameter of the stimulus while the digital circuitry continuously receives new digital data from the conversion circuitry. The digital circuitry can be reconfigured to characterize a different parameter for the same type or for a different type of stimulus.

Abstract: Described are a system and method for monitoring and characterizing a stimulus in order to detect transient phenomena. An analog signal represents the stimulus. Conversion circuitry receives the analog signal and continuously converts the analog signal into digital data. Digital circuitry continuously receives the digital data from the conversion circuitry and dynamically computes from the digital data a value that characterizes a parameter of the stimulus while the digital circuitry continuously receives new digital data from the conversion circuitry. The digital circuitry can be reconfigured to characterize a different parameter for the same type or for a different type of stimulus.

Abstract: Method and apparatus for limiting optical radiation to an optical sensor are disclosed for protecting the sensor against damage from high intensity optical radiation. A fixed electric field is established between a pair of spaced electrodes by connection of the electrodes to a DC voltage source. Small solid particles oscillate back and forth in the electric field between the electrodes. Incident optical radiation is focused at a focal plane at the oscillating solid particles, and energy transmitted through the oscillating particles is focused at the optical sensor. The transmittance of the particle-containing space is substantially constant for incident optical radiation intensity up to a threshold level below which the sensor is undamaged by the radiation.