公开(公告)号：US20180259454A1

公开(公告)日：2018-09-13

申请号：US15487435

申请日：2017-04-14

Applicant: Massachusetts Institute of Technology

Inventor： Ayush Bhandari ,  Christopher Barsi ,  Achuta Kadambi ,  Ramesh Raskar

IPC: G01N21/64

CPC classification number: G01N21/6408 ,  G01N21/6456 ,  G01N2201/0691 ,  G01N2201/126 ,  G01N2201/129 ,  G07D7/1205 ,  G07D7/2016 ,  G07D7/205

Abstract: A light source may illuminate a scene with amplitude-modulated light. The scene may include fluorescent material. The amplitude modulation may be periodic, and the frequency of the amplitude modulation may be swept. During the sweep, a time-of-flight sensor may take measurements of light returning from the scene. A computer may calculate, for each pixel in the sensor, a vector of complex numbers. Each complex number in the vector may encode phase and amplitude of light incident at the pixel and may correspond to measurements taken at a given frequency in the sweep. A computer may, based on phase of the complex numbers for a pixel, calculate fluorescence lifetime and scene depth of a scene point that corresponds to the pixel.

公开(公告)号：US10190983B2

公开(公告)日：2019-01-29

申请号：US15487438

申请日：2017-04-14

Applicant: Massachusetts Institute of Technology

Inventor： Ayush Bhandari ,  Christopher Barsi ,  Achuta Kadambi ,  Ramesh Raskar

IPC: G01N21/64

Abstract: A light source may illuminate a scene with pulsed light that is pulsed non-periodically. The scene may include fluorescent material that fluoresces in response to the pulsed light. The pulsed light signal may comprise a maximum length sequence or Gold sequence. A lock-in time-of-flight sensor may take measurements of light returning from the scene. A computer may, for each pixel in the sensor, perform a Discrete Fourier Transform on measurements taken by the pixel, in order to calculate a vector of complex numbers for the pixel. Each complex number in the vector may encode phase and amplitude of incident light at the pixel and may correspond to measurements taken at a given time interval during the pulsed light signal. A computer may, based on phase of the complex numbers for a pixel, calculate fluorescence lifetime and scene depth of a scene point that corresponds to the pixel.

公开(公告)号：US20180259455A1

公开(公告)日：2018-09-13

申请号：US15487438

申请日：2017-04-14

Applicant: Massachusetts Institute of Technology

Inventor： Ayush Bhandari ,  Christopher Barsi ,  Achuta Kadambi ,  Ramesh Raskar

IPC: G01N21/64

CPC classification number: G01N21/6408 ,  G01N21/6456 ,  G01N2201/0691 ,  G01N2201/126 ,  G01N2201/129 ,  G07D7/00

Abstract: A light source may illuminate a scene with pulsed light that is pulsed non-periodically. The scene may include fluorescent material that fluoresces in response to the pulsed light. The pulsed light signal may comprise a maximum length sequence or Gold sequence. A lock-in time-of-flight sensor may take measurements of light returning from the scene. A computer may, for each pixel in the sensor, perform a Discrete Fourier Transform on measurements taken by the pixel, in order to calculate a vector of complex numbers for the pixel. Each complex number in the vector may encode phase and amplitude of incident light at the pixel and may correspond to measurements taken at a given time interval during the pulsed light signal. A computer may, based on phase of the complex numbers for a pixel, calculate fluorescence lifetime and scene depth of a scene point that corresponds to the pixel.

公开(公告)号：US10337993B2

公开(公告)日：2019-07-02

申请号：US15487435

申请日：2017-04-14

Applicant: Massachusetts Institute of Technology

Inventor： Ayush Bhandari ,  Christopher Barsi ,  Achuta Kadambi ,  Ramesh Raskar

IPC: G01N21/64 ,  G07D7/00

Abstract: A light source may illuminate a scene with amplitude-modulated light. The scene may include fluorescent material. The amplitude modulation may be periodic, and the frequency of the amplitude modulation may be swept. During the sweep, a time-of-flight sensor may take measurements of light returning from the scene. A computer may calculate, for each pixel in the sensor, a vector of complex numbers. Each complex number in the vector may encode phase and amplitude of light incident at the pixel and may correspond to measurements taken at a given frequency in the sweep. A computer may, based on phase of the complex numbers for a pixel, calculate fluorescence lifetime and scene depth of a scene point that corresponds to the pixel.