G01S17/26

LIDAR system to adjust doppler effects

Doppler correction of phase-encoded LIDAR includes a code indicating a sequence of phases for a phase-encoded signal, and determining a first Fourier transform of the signal. A laser optical signal is used as a reference and modulated based on the code to produce a transmitted phase-encoded optical signal. A returned optical signal is received in response. The returned optical signal is mixed with the reference. The mixed optical signals are detected to produce an electrical signal. A cross spectrum is determined between in-phase and quadrature components of the electrical signal. A Doppler shift is based on a peak in the cross spectrum. A device is operated based on the Doppler shift. Sometimes a second Fourier transform of the electrical signal and the Doppler frequency shift produce a corrected Fourier transform and then a cross correlation. A range is determined based on a peak in the cross correlation.

TOF SENSOR, IMAGE SENSING DEVICE AND OPERATION METHOD THEREOF
20220365218 · 2022-11-17 ·

A Time of Flight (TOF) sensor using dual frequency includes: a light source for irradiating light to an external subject; a phase modulation controller for providing the light source with a clock so that the light source irradiates irradiation light according to a timing of a global clock, and generating a plurality of pixel clocks having dual frequency; and a pixel array for receiving the pixel clocks and generating a pixel signal, wherein the pixel clocks have a different number of phases according to different exposure frames at the dual frequency.

TOF SENSOR, IMAGE SENSING DEVICE AND OPERATION METHOD THEREOF
20220365218 · 2022-11-17 ·

A Time of Flight (TOF) sensor using dual frequency includes: a light source for irradiating light to an external subject; a phase modulation controller for providing the light source with a clock so that the light source irradiates irradiation light according to a timing of a global clock, and generating a plurality of pixel clocks having dual frequency; and a pixel array for receiving the pixel clocks and generating a pixel signal, wherein the pixel clocks have a different number of phases according to different exposure frames at the dual frequency.

Optical designs using cylindrical lenses for improved resolution in lidar systems

An optical system includes a laser source having an emission area that has a first width in a first direction and a first height in a second direction orthogonal to the first direction, the first width being greater than the first height. The optical system further includes a cylindrical lens having a negative power and positioned in front of the laser source. The cylindrical lens is oriented such that a power axis of the cylindrical lens is along the first direction. The cylindrical lens is configured to transform the emission area of a laser beam emitted by the laser source into a virtual emission area having a virtual width and a virtual height, where the virtual width is less than the first width. The optical system further includes an rotationally symmetric lens positioned downstream from the cylindrical lens and configured to collimate and direct the laser beam towards a far-field.

Optical designs using cylindrical lenses for improved resolution in lidar systems

An optical system includes a laser source having an emission area that has a first width in a first direction and a first height in a second direction orthogonal to the first direction, the first width being greater than the first height. The optical system further includes a cylindrical lens having a negative power and positioned in front of the laser source. The cylindrical lens is oriented such that a power axis of the cylindrical lens is along the first direction. The cylindrical lens is configured to transform the emission area of a laser beam emitted by the laser source into a virtual emission area having a virtual width and a virtual height, where the virtual width is less than the first width. The optical system further includes an rotationally symmetric lens positioned downstream from the cylindrical lens and configured to collimate and direct the laser beam towards a far-field.

Fiber-bundled frequency-shifted transmitter for direct detection LIDAR
11588551 · 2023-02-21 · ·

A method includes generating, using a transmitter, an optical signal for each fiber incoherently combined in a fiber bundle. The method also includes transmitting the optical signal from each fiber as pulses at a target. The method further includes receiving, using a receiver array, the pulses of the optical signals and identifying one or more parameters of the target based on the pulses of the optical signals.

Fiber-bundled frequency-shifted transmitter for direct detection LIDAR
11588551 · 2023-02-21 · ·

A method includes generating, using a transmitter, an optical signal for each fiber incoherently combined in a fiber bundle. The method also includes transmitting the optical signal from each fiber as pulses at a target. The method further includes receiving, using a receiver array, the pulses of the optical signals and identifying one or more parameters of the target based on the pulses of the optical signals.

METHOD AND SYSTEM FOR CLASSIFICATION OF AN OBJECT IN A POINT CLOUD DATA SET

A method for classifying an object in a point cloud includes computing first and second classification statistics for one or more points in the point cloud. Closest matches are determined between the first and second classification statistics and a respective one of a set of first and second classification statistics corresponding to a set of N classes of a respective first and second classifier, to estimate the object is in a respective first and second class. If the first class does not correspond to the second class, a closest fit is performed between the point cloud and model point clouds for only the first and second classes of a third classifier. The object is assigned to the first or second class, based on the closest fit within near real time of receiving the 3D point cloud. A device is operated based on the assigned object class.

Time-of-flight measurements using linear inverse function

One example provides a time-of-flight depth imaging system configured to modulate light emitted from a light source to illuminate an environment with modulated light, and for each of one or more modulation frequencies, integrate an image at each phase step of a plurality of phase steps, and sense a temperature of the light source and/or image sensor via one or more temperature sensors to acquire a measured temperature. The instructions are further executable to, and for each pixel of one or more pixels of the image sensor, determine a complex phasor based upon the measured temperature using a linear inverse function for each modulation frequency, determine a phase shift between the light emitted from the light source and light from the light source reflected back by the environment based on the complex phasor, and output a depth value for the pixel based upon the phase shift.

Time-of-flight measurements using linear inverse function

One example provides a time-of-flight depth imaging system configured to modulate light emitted from a light source to illuminate an environment with modulated light, and for each of one or more modulation frequencies, integrate an image at each phase step of a plurality of phase steps, and sense a temperature of the light source and/or image sensor via one or more temperature sensors to acquire a measured temperature. The instructions are further executable to, and for each pixel of one or more pixels of the image sensor, determine a complex phasor based upon the measured temperature using a linear inverse function for each modulation frequency, determine a phase shift between the light emitted from the light source and light from the light source reflected back by the environment based on the complex phasor, and output a depth value for the pixel based upon the phase shift.