초록 ▼

A light detection and ranging (LIDAR) system uses dual detectors to provide three-dimensional imaging of underwater objects (or other objects hidden by a partially transmissive medium). One of the detectors is a low resolution, high bandwidth detector. The other is a high resolution, narrow bandwidt

A light detection and ranging (LIDAR) system uses dual detectors to provide three-dimensional imaging of underwater objects (or other objects hidden by a partially transmissive medium). One of the detectors is a low resolution, high bandwidth detector. The other is a high resolution, narrow bandwidth detector. An initial laser pulse is transmitted to known x-y coordinates of a target area. The photo signals returned from the target area from this initial pulse are directed to the low resolution, high bandwidth detector, where a preliminary determination as to the location (depth, or z coordinate) of an object in the target area is made based on the time-of-receipt of the return photo signal. A second laser pulse is then transmitted to the target area and the return photo signals from such second laser pulse are directed to the high resolution, narrow bandwidth detector. This high resolution detector is gated on at a time so that only photo signals returned from a narrow “slice”of the target area (corresponding to the previously detected depth of the object) are received. An image of the detected object is then reconstructed from the signals generated by the high resolution detector. In a preferred embodiment, the two detectors are housed in a single digicon tube, with magnetic deflection being used to steer the beam to the appropriate detector.

대표청구항 ▼

A light detection and ranging (LIDAR) method for remotely detecting and identifying the location of an object in a target area comprising: (a) transmitting a first pulse of laser energy at known coordinates in the target area from a location spaced from the target area; (b) receiving with a receiver

A light detection and ranging (LIDAR) method for remotely detecting and identifying the location of an object in a target area comprising: (a) transmitting a first pulse of laser energy at known coordinates in the target area from a location spaced from the target area; (b) receiving with a receiver a first return pulse of laser energy comprising a reflection of the first pulse from an object within the target area and forming a first return signal therefrom; (c) directing the first return signal to a low resolution detector to develop a first output signal representative of the first return pulse and including an object signature for the object within the target area; (d) processing the first output signal to measure the time at which the object signature is observed in the first output signal relative to the time at which said first pulse is transmitted, whereby a round-trip signal transmission time is determined, said round-trip signal transmission time providing a measure of the depth of said object within the target area; (e) transmitting a second pulse of laser energy at the same coordinates of the target area as was the first pulse of laser energy; (f) receiving with the receiver a second return pulse of laser energy after waiting said round-trip signal transmission time from the transmission of said second pulse, whereby said second return pulse contains primarily laser energy reflected from said object, and forming a second return signal therefrom; (g) directing the second return signal to a high resolution detector to develop a second output signal representative of the second return signal; and (h) electronically processing the second return pulse to form an image of the detected object.