Optical probe for detecting transitory and repetitive light signals

Abstract

The invention relates to a device for detecting transitory and repetitive light signals from a radiant energy source. The invention comprises a detector means for detecting the light signals and for providing output signals indicative of the presence thereof, first indicator means coupled to the detector means for providing a continuous indication of the initial presence of the light signals and second indicator means for providing an indication of the repetition rate of the light signals. In a particular embodiment, a video amplifier circuit is coupled to a detector circuit to provide an amplified output and a comparator circuit is coupled to the video amplifier circuit and senses the video amplifier circuit output signals above a specified level and produces standard logic level output signals. The output signals from the comparator circuit are coupled to a first indicator circuit incorporating a first light-emitting diode which provides a continuous indication of the initial presence of the light signal. A reset button is incorporated to reset the first indicator circuit, extinguishing the first diode, so it can indicate the presence of subsequent signals. The comparator is also coupled to a second indicator circuit incorporating a second light-emitting diode which is adapted to briefly light for each incoming singal such that a low repetitive rate gives a dim light and a high repetitive rate gives a bright indication, thus providing an indication of the approximate rate of repetitive incoming light signals. An audio amplifier circuit is coupled to the video amplifier circuit and is adapted to provide an audio output. A detector/filter with buffer circuit is coupled to the audio amplifier circuit to provide photometric or radiometric outputs. Provisions are made for the coupling of a flexible fiber-optic cable to the probe so that light signals in otherwise inaccessible areas can be monitored.