LiDAR device and operating method thereof

A light detection and ranging (LiDAR) device comprising:

• an optical phased array configured to modulate a phase of light incident on the optical phased array and emit the light that is phase-modulated;
• a first photodetector configured to detect, as a reference light, the light emitted from the optical phased array in a first direction toward the first photodetector, and generate a reference signal based on the reference light;
• a waveguide comprising an area having a width that decreases from the optical phased array toward the first photodetector, and configured to receive the reference light from the optical phased array and output the reference light to the first photodetector;
• a second photodetector configured to detect, as a target light including information about an object, the light emitted from the optical phased array in a second direction toward the object, and generate a target signal based on the target light;
• and
• a processor configured to determine a distance between the LiDAR device and the object based on a cross-correlation between the reference signal and the target signal.

An operating method of a light detection and ranging (LiDAR) device, the operating method comprising:

• emitting light that is phase-modulated by a phase modulation array through an antenna array;
• receiving, by a photodetector from the antenna array, the light emitted from the antenna array in a first direction toward the photodetector, as reference light that is used to determine a distance between the LiDAR device and an object, wherein the photodetector is connected to the antenna array via a waveguide that is in contact with the antenna array and the photodetector;
• detecting, by the photodetector, the light emitted from the antenna array in a second direction toward the object, as a target light including information about the object;
• generating a reference signal based on the reference light, and generating a target signal based on the target light;
• and
• determining the distance between the LiDAR device and the object based on a cross-correlation between the reference signal and the target signal,
• wherein the phase modulation array, the antenna array, the waveguide, and the photodetector are provided on a same surface of a same substrate.

A distance sensing device comprising:

• a light emitter configured to emit light in a first direction toward an object and in a second direction different from the first direction;
• an optical phased array configured to modulate a phase of light incident on the optical phased array and emit the light that is phase-modulated;
• a light receiver comprising a first photodetector configured to detect the light emitted to the object and reflected from the object as an analog target signal, and a second photodetector configured to detect, directly from the light emitter, the light emitted in the second direction as an analog reference signal;
• a single analog-to-digital converter (ADC) configured to receive the analog target signal and the analog reference signal and convert the analog target signal and the analog reference signal to a digital target signal and a digital reference signal, respectively;
• and
• a processor configured to determine a distance between the distance sensing device and the object based on information of a time point at which a cross-correlation between the digital target signal and the digital reference signal is maximized,
• wherein the optical phased array comprises an optical splitter, a phase modulation array, and an antenna array, and
• wherein the first photodetector is connected to the antenna array via a waveguide that is in contact with the antenna array and the first photodetector and configured to receive the reference light used to determine the distance from the antenna array via the waveguide, and
• wherein the optical splitter, the phase modulation array, the antenna array, the waveguide, and the first photodetector are provided on a same surface of a same substrate.