LIDAR and ranging method using same

A LIDAR ranging method, comprising:

• circularly allocating, by a light routing device, each periodic signal of a transmit signal to each light channel in a chronological order, so that the light routing device does not need to wait for a previous signal to return before sending a next signal;
• monitoring a beat signal or a returned light pulse signal in each light channel;
• and
• calculating a target distance according to a frequency of the beat signal or a return delay time of the light pulse signal,
• wherein circularly allocating comprises guiding each periodic signal to each light channel in arrangement order of the light channels,
• wherein the light routing device is set between a laser source and all light channels,
• the LIDAR ranging method further comprising circularly allocating at least one periodic signal of the transmit signal to each light channel in a chronological order via the light routing device before a reflected signal from a farthest target object within a maximum-ranging range is received in any light channel, wherein a single light detector needs to be equipped in each light channel.