Three-dimensional imaging system and method

A method for ranging using a three-dimensional imaging system, comprising:

• providing an optical modulator on an optical path of an optical emitter, such that pulsed light emitted by the optical emitter has a time-varying optical state when returning via a target scene;
• receiving an optical signal modulated via the optical modulator by means of an optical element array, wherein the optical element array comprises at least three polarization components having polarization directions different from each other;
• deploying a photoelectric detector behind the optical element array to receive the optical signal passing through the optical element array and to convert the received optical signal to an electrical signal;
• and
• providing a controller to be electrically connected to the optical emitter, the optical modulator, and the photoelectric detector, wherein the controller applies a control to the optical modulator, the optical modulator modulates a return part of light pulses into a function of time based on the control, and the controller calculates a distance between each pixel point in the target scene and the optical emitter and/or the relative light intensity of each pixel point in the target scene based on the electrical signal from the photoelectric detector and the control applied to the optical modulator;
• wherein the three-dimensional imaging system comprises:
• the optical emitter, configured to emit the light pulses to the target scene, the target scene returning at least part of the light pulses;
• wherein, the three-dimensional imaging system further comprises:
• the optical modulator, configured to modulate an optical state of at least part of the light pulses emitted from the optical emitter and/or of at least part of light pulses returned from the target scene;
• the optical element array, configured to receive at least part of the modulated light pulses, wherein at least within a first preset time range before the emission of the light pulses and/or within a second preset time range after the emission of the light pulses, the optical element array has a function of transmitting light of at least three optical states different from each other, and the optical states comprise at least one of a polarization state, transmission, or reflectivity;
• the photoelectric detector, comprising an imaging lens, configured to receive an optical signal passing through the optical element array, and convert the received optical signal to the electrical signal;
• and
• the controller, wherein the controller applies a control to the optical modulator by means of a circuit, the optical modulator modulates the optical state of the light pulses emitted from the optical emitter and/or of at least part of the light pulses returned from the target scene into a function of time based on the control, and the controller calculates the distance between each pixel point in the target scene and the optical emitter and/or a relative light intensity of each pixel point in the target scene based on the electrical signal from the photoelectric detector and the control applied to the optical modulator.

A method for ranging using a three-dimensional imaging system, comprising:

• taking a first shot of a target scene at an initial time point to obtain baseline image information;
• and
• taking a second shot at a next time point at a predetermined time interval from the initial time point to obtain comparative image information,
• wherein, a distance between each pixel point in the target scene and an optical emitter and/or the relative light intensity of each pixel point in the target scene is determined based on the baseline image information and the comparative image information;
• wherein the three-dimensional imaging system comprises:
• the optical emitter, configured to emit light pulses to the target scene, the target scene returning at least part of the light pulses;
• wherein, the three-dimensional imaging system further comprises:
• an optical modulator, configured to modulate an optical state of at least part of the light pulses emitted from the optical emitter and/or of at least part of light pulses returned from the target scene;
• an optical element array, configured to receive at least part of the modulated light pulses, wherein at least within a first preset time range before the emission of the light pulses and/or within a second preset time range after the emission of the light pulses, the optical element array has a function of transmitting light of at least three optical states different from each other, and the optical states comprise at least one of a polarization state, transmission, or reflectivity;
• a photoelectric detector, comprising an imaging lens, configured to receive an optical signal passing through the optical element array, and convert the received optical signal to an electrical signal;
• and
• a controller, wherein the controller applies a control to the optical modulator by means of a circuit, the optical modulator modulates the optical state of the light pulses emitted from the optical emitter and/or of at least part of the light pulses returned from the target scene into a function of time based on the control, and the controller calculates the distance between each pixel point in the target scene and the optical emitter and/or a relative light intensity of each pixel point in the target scene based on the electrical signal from the photoelectric detector and the control applied to the optical modulator.