Lidar system and its control method

Abstract

A LIDAR system may include: a light generator configured to irradiate a laser to an object disposed in a blind section of the LIDAR system; a light receiver configured to sensing light reflected from the object; a receiver configured to receive a signal converted into an electric signal in the light receiver; a comparator configured to determine whether the signal is a voltage value which is equal to or greater than a predetermined reference; and a controller configured to control a pulse width of the laser irradiated to the object according to the determination.

What is claimed is: 
     
         1 . A light detection and ranging (LIDAR) system comprising:
 a light generator configured to irradiate a laser to an object disposed in a blind section of the LIDAR system;   a light receiver configured to sense light reflected from the object;   a receiver configured to receive a signal that is converted into an electric signal in the light receiver;   a comparator configured to determine whether the signal is a voltage value which is equal to or greater than a predetermined reference; and   a controller configured to control a pulse width of the laser according to the determination of the comparator.   
     
     
         2 . The LIDAR system of  claim 1 , wherein the controller is configured to control an output power of the light generator through pulse width modulation. 
     
     
         3 . The LIDAR system of  claim 1 , wherein when the signal is a voltage value which is less than the predetermined reference, the comparator is configured to transmit a flag to the controller. 
     
     
         4 . The LIDAR system of  claim 3 , wherein the controller is configured to increase the pulse width of the laser re-irradiated to the object in response to the flag. 
     
     
         5 . The LIDAR system of  claim 4 , wherein until the signal is a voltage value which is equal to or greater than the predetermined reference, the comparator is configured to transmit the flag to the controller. 
     
     
         6 . The LIDAR system of  claim 1 , wherein the controller further comprises:
 an output unit configured to output a pulse signal toward an internal communication channel;   a pulse comparator configured to compare the pulse signal passing with a predetermined reference voltage;   a determination unit configured to determine whether the pulse signal is attenuated based on the comparison; and   a de-emphasis unit configured to determine whether the pulse signal is modulated based on the determination.   
     
     
         7 . The LIDAR system of  claim 6 , wherein when it is determined that the pulse signal is attenuated, the de-emphasis unit is configured to perform amplitude modulation for a rising edge of the pulse signal. 
     
     
         8 . The LIDAR system of  claim 6 , wherein the pulse comparator is configured to:
 output a comparison result of a high level when the pulse signal is less than the reference voltage; and   output a comparison result of a low level when the pulse signal is equal to or greater than the reference voltage.   
     
     
         9 . The LIDAR system of  claim 8 , wherein the determination unit is configured to:
 determine that the pulse signal is attenuated when receiving the comparison result of the high level from the pulse comparator;   determine that the pulse signal is in a normal state when receiving the comparison result of the low level from the pulse comparator; and   activate the de-emphasis unit when it is determined that the pulse signal is attenuated.   
     
     
         10 . The LIDAR system of  claim 6 , wherein the de-emphasis unit further comprises:
 a de-emphasis circuit connected to an output terminal of the output unit;   a NOR gate configured to transmit an enable signal for activating the de-emphasis circuit when it is determined that the pulse signal is attenuated according to the determination; and   a delay control connected to at least one input terminal of the NOR gate to delay and transmit input data that is input into the determination unit.   
     
     
         11 . The LIDAR system of  claim 10 , wherein the de-emphasis circuit is configured to perform pulse width modulation of the pulse signal. 
     
     
         12 . A control method using a light detection and ranging (LIDAR) system, comprising:
 irradiating a laser to an object disposed in a blind section of the LIDAR system;   receiving a signal reflected from the object;   determining whether the received signal is a voltage value which is equal to or greater than a predetermined reference; and   controlling a pulse width of the laser irradiated to the object according to the determination of the voltage value of the signal.   
     
     
         13 . The control method of  claim 12 , wherein the method further comprises:
 transmitting a flag when the received signal is a voltage value which is less than the predetermined reference.   
     
     
         14 . The control method of  claim 13 , wherein the method further comprises:
 increasing the pulse width of the laser re-irradiated to the object in response to the flag.   
     
     
         15 . The control method of  claim 14 , wherein the method further comprises:
 transmitting the flag until a signal re-irradiated to and reflected on the object becomes a voltage value which is equal to or greater than the predetermined reference.