초록 ▼

A coaxial, spacially gated, range gated, pulsed-beam, scanning system for use in turbid media, such as seawater, fog, snow, rain, blowing dust or sand. A laser emits a pulsed beam of light which travels to a beam splitter where part of the beam is transmitted and part is deflected. The transmitted b

A coaxial, spacially gated, range gated, pulsed-beam, scanning system for use in turbid media, such as seawater, fog, snow, rain, blowing dust or sand. A laser emits a pulsed beam of light which travels to a beam splitter where part of the beam is transmitted and part is deflected. The transmitted beam is then deflected by an x-y scanning element such that a target is sequentially illuminated in a point-by-point manner. Light refected from the target travels back along the same path as the transmitted beam and is deflected by the beam splitter to a light sensor, such as photomultiplier tube. The field-of-view of the light sensor is limited and controlled in such a manner that it receives light only from that portion of the target that is illuminated by the portion of the transmitted beam light that has not been scattered by the turbid medium, and the system is range gated to accept only that portion of the output of the light sensor which is representative of the intensity of the non-scattered beam pulse which is reflected by the target. Range gatting may be triggered by detection of the leading edge of the reflected light pulse as it enters the sensor or by detection of the portion of the emitted beam that is deflected by the beam splitter. This allows use of a free-running laser.

대표청구항 ▼

A viewing system for use in turbid media comprising: light pulse emitting means for emitting a pulse of light; beam splitter means for receiving the emitted light pulse from the emitting means, for transmitting at least a portion of the emitted light received, and for deflecting a return reflected l

A viewing system for use in turbid media comprising: light pulse emitting means for emitting a pulse of light; beam splitter means for receiving the emitted light pulse from the emitting means, for transmitting at least a portion of the emitted light received, and for deflecting a return reflected light pulse; controllable biaxial scanning means for receiving the transmitted light pulse from the beam splitter and directing the transmitted light pulse to a target to sequentially illuminate the target, for receiving the reflected light pulse from the target, and deflecting said reflected light pulse back to the beam splitter; and receiver means for receiving the reflected return light pulse after deflection from the beam splitter and for providing or producing a signal representative of the intensity of said light pulse.