Common aperture time-division-multiplexed laser rangefinder

Abstract

An optical rangefinder includes an optical portion for directing optical radiation from a generator to and through an optical aperture, and for directing reflected energy of the optical radiation that is received back through the aperture to a detector, the optical portion having an optical switch. In a first operational mode the optical switch routes optical radiation from the generator in a manner that facilitates the directing of the optical radiation to and through the optical aperture, and in a second operational mode the optical switch routes the reflected energy in a manner that facilitates the directing of the reflected energy to the detector. A control portion is responsive to the detector, and controls the generator and the optical switch.

1 . An apparatus comprising an optical rangefinder that includes: 
 an optical aperture;    a generator that can emit optical radiation;    a detector responsive to optical radiation;    an optical portion for directing optical radiation from said generator to and through said aperture, and for directing reflected energy of the optical radiation that is received back through said aperture to said detector, said optical portion having an optical switch with first and second operational modes, wherein in said first operational mode said optical switch routes optical radiation from said generator in a manner that facilitates said directing of the optical radiation to and through said optical aperture, and in said second operational mode said optical switch routes the reflected energy in a manner that facilitates said directing of the reflected energy to said detector; and    a control portion that is responsive to said detector and that controls said generator and said optical switch.    
   
   
       2 . An apparatus according to  claim 1 , wherein said generator emits infrared radiation, and said detector is responsive to infrared radiation.  
   
   
       3 . An apparatus according to  claim 2 , wherein said generator includes an infrared laser.  
   
   
       4 . An apparatus according to  claim 2 , including a further aperture, said optical portion directing visible radiation received through said optical aperture along an optical path extending to and through said further aperture.  
   
   
       5 . An apparatus according to  claim 4 , 
 wherein said optical portion includes a beam splitter disposed along said optical path between first and second portions thereof; and    wherein said beam splitter causes visible radiation arriving at said beam splitter from said optical aperture along said first portion of said optical path to thereafter travel away from said beam splitter toward said further aperture along said second portion of said optical path, causes infrared radiation arriving at said beam splitter along said first portion of said optical path to thereafter travel away from said beam splitter toward said optical switch along a further path, and causes infrared radiation that arrives at said beam splitter along said further path to thereafter travel away from said beam splitter along said first portion of said optical path.    
   
   
       6 . A method of operating an optical rangefinder having an optical aperture, an optical radiation generator, an optical radiation detector, and an optical switch, comprising: 
 directing optical radiation from said generator to and through said optical aperture, including operating said optical switch in a first operational mode in which said optical switch routes optical radiation from said generator in a manner that facilitates said directing of the optical radiation to and through said optical aperture; and    directing reflected energy of the optical radiation that is received back through said optical aperture to said detector, including operating said optical switch in a second operational mode in which said optical switch routes the reflected energy in a manner that facilitates said directing of the reflected energy to said detector.    
   
   
       7 . A method according to  claim 6 , including: 
 causing said radiation emitted by said generator to be infrared radiation; and    causing said detector to be responsive to infrared radiation.    
   
   
       8 . A method according to  claim 7 , including directing visible radiation received through said optical aperture along an optical path extending to and through a further aperture.  
   
   
       9 . A method according to  claim 8 , including: 
 providing a beam splitter along said optical path between first and second portions thereof;    causing visible radiation arriving at said beam splitter from said optical aperture along said first portion of said optical path to thereafter travel away from said beam splitter toward said further aperture along said second portion of said optical path;    causing infrared radiation arriving at said beam splitter along said first portion of said optical path to thereafter travel away from said beam splitter toward said optical switch along a further path; and    causing infrared radiation that arrives at said beam splitter along said further path to thereafter travel away from said beam splitter along said first portion of said optical path.    
   
   
       10 . An apparatus comprising an optical rangefinder that includes: 
 means defining an optical aperture;    generator means for emitting optical radiation;    detector means for detecting optical radiation;    optical means for directing optical radiation from said generator means to and through said aperture, and for directing reflected energy of the optical radiation that is received back through said aperture to said detector means, said optical means including optical switch means having a first operational mode for routing optical radiation from said generator means in a manner that facilitates said directing of the optical radiation to and through said optical aperture, and having a said second operational mode for routing the reflected energy in a manner that facilitates said directing of the reflected energy to said detector means; and    control means for controlling said generator means and said optical switch means, said control means being responsive to said detector means.    
   
   
       11 . An apparatus according to  claim 10 , wherein said generator means emits infrared radiation, and said detector means is responsive to infrared radiation.  
   
   
       12 . An apparatus according to  claim 11 , including means defining a further aperture, said optical means directing visible radiation received through said optical aperture along an optical path extending to and through said further aperture.  
   
   
       13 . An apparatus according to  claim 12 , 
 wherein said optical means includes beam splitter means disposed along said optical path between first and second portions thereof; and    wherein said beam splitter means causes visible radiation arriving at said beam splitter means from said optical aperture along said first portion of said optical path to thereafter travel away from said beam splitter means toward said further aperture along said second portion of said optical path, causes infrared radiation arriving at said beam splitter means along said first portion of said optical path to thereafter travel away from said beam splitter means toward said optical switch means along a further path, and causes infrared radiation that arrives at said beam splitter means along said further path to thereafter travel away from said beam splitter means along said first portion of said optical path.