US 12,292,533 B2
Beam steering LADAR sensor
Patrick B Gilliland, Santa Barbara, CA (US); and Roger Stettner, Santa Barbara, CA (US)
Assigned to Continental Autonomous Mobility US, LLC, Auburn Hills, MI (US)
Filed by Continental Autonomous Mobility US, LLC, Auburn Hills, MI (US)
Filed on Oct. 16, 2021, as Appl. No. 17/451,154.
Application 17/451,154 is a continuation of application No. 16/151,067, filed on Oct. 3, 2018, granted, now 11,175,384.
Application 16/151,067 is a continuation of application No. 14/656,936, filed on Mar. 13, 2015, granted, now 10,126,411, issued on Nov. 13, 2018.
Prior Publication US 2022/0035006 A1, Feb. 3, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. G01S 7/481 (2006.01); G01S 7/4863 (2020.01); G01S 13/931 (2020.01); G01S 17/894 (2020.01); G01S 17/931 (2020.01)
CPC G01S 7/4814 (2013.01) [G01S 7/4811 (2013.01); G01S 7/4817 (2013.01); G01S 7/4863 (2013.01); G01S 17/894 (2020.01); G01S 17/931 (2020.01); G01S 2013/93277 (2020.01)] 11 Claims
OG exemplary drawing
 
1. A ladar system mountable to a vehicle, said system comprising:
a laser transmitter comprising at least one semiconductor laser having a pulsed laser light output configured to transmit light through a transmitting optic adapted to illuminate a reflecting surface in a field of view;
a laser drive circuit connected to said at least one semiconductor laser and adapted to electrically drive said at least one semiconductor laser in a predetermined sequence;
a laser beam steering mechanism adapted to scan the pulsed laser light output sequentially through the field of view;
a time zero reference circuit having a time zero reference electrical output configured to signal the beginning of a pulsed laser light transmission;
receiving optics adapted to collect and condition the pulsed laser light reflected from the reflecting surface;
a two-dimensional array of light sensitive detectors positioned at a focal plane of said receiving optics, each of said light sensitive detectors configured to intercept a pixellated portion of the pulsed laser light output reflected from the reflecting surface, and each light sensitive detector having an output configured to produce an electrical response signal;
a detector bias circuit connected to a voltage distribution grid of said array of light sensitive detectors; and
a readout integrated circuit with a clock circuit and a plurality of unit cell electrical circuits;
each of said unit cell electrical circuits having an input connected to said clock circuit and to said time zero reference electrical output, and having an amplifier with an input connected to one of said light sensitive detector outputs, and each amplifier having an output, and a pulse detection circuit connected to said amplifier output, and said pulse detection circuit having a termination output, a counter connected to said time zero reference electrical output and to said clock circuit, said counter started counting by the time zero reference electrical output, and said counter connected to, and stopped counting by the termination output, and the counter having an output proportional to the distance to the reflecting surface, thereby establishing a direct time of flight distance measurement.