Coherent lidar apparatus including light frequency stabilization apparatus based on complex opll

A LiDAR apparatus comprising:

• a first light source configured to output light for detecting a distance up to a target;
• a second light source configured to output light for detecting a speed of the target;
• a third light source configured to output light for detecting a directivity of the target that moves;
• a light combination unit configured to combine pieces of light radiated by the first to third light sources, respectively;
• an optical system configured to adjust a path or state of light to be output to an outside or reflected light that is reflected by the target;
• an interferometer configured to receive the light that has been combined by the light combination unit and the reflected light that has passed through the optical system and to make the combined light and the reflected light interfere with each other;
• and
• a detection unit configured to detect information on a distance and speed of the target by receiving the light subjected to the interference in the interferometer.