CW-LASER ILLUMINATOR DETECTOR

摘要

The present invention relates to a incident laser detection apparatus. The apparatus comprises scanning means for scanning a field of view and for responding to radiation of a predetermined range of wavelengths to produce an analog signal which corresponds to the intensity of the radiation. An analog-digital conversion means is provided for converting the analog signal to a series of digital signals. An averaging means provided for deriving from each successive series of the digital signals for successive scans of the field of view a series of averaged digital signals. A digital memory is provided for storing successive series of averaged digital signals for successive scans of the field of view. A comparator is provided which is responsive to the digital signals and the averaged digital signals for successive scanning positions whereby an instantaneous digital value for a given scanning position of a given scan is compared with the stored averaged digital value for the same given scanning position of a selected previous scan. Finally, means are provided for signalling the presence of a discrepancy exceeding a predetermined threshold sensed by the comparator between the stored averaged digital value and the instantaneous digital value for any scanning position.