# US 8,788,022 B2 · N-time-gate data-type for TPSF-based optical imaging > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,788,022 B2 - Document ID: US8788022B2 - Status: Granted - Kind: B2 - Application number: 10/757,937 - Filed: 2004-01-16 - Published: 2004-07-29 - Granted: 2014-07-22 - Earliest claimed: 2001-07-16 - Assignees: President and Fellows of Harvard College - Applicants: David Jonathan Hall - Inventors: David Jonathan Hall - Web page: https://patentgrep.com/patent/US8788022B2 ## CPC - A61B 5/0091: {for mammography} - A61B 5/0059: {using light, e.g. diagnosis by transillumination, diascopy, fluorescence (photoacoustic A61B5/0093; optical measurement of heart rate A61B5/02416; optical measurement of blood flow A61B5/0261; optical measurement of analytes A61B5/1455)} - A61B 5/4312: {Breast evaluation or disorder diagnosis (optical mammography A61B5/0091)} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract There is provided a method and system for optical imaging of a light scattering object. The method comprises the detection of one or more time-gates of a temporal point spread function (TPSF) to be used to construct an image of optical properties of the object. The method also comprises the simultaneous detection of two or more selected time-gates using a time-gated camera. The method enables more efficient spatial-temporal acquisition of optical signals for imaging purposes. ## Claims ### Claim 1 A method for optical imaging of a light scattering object, the method comprising steps of: i) selecting a plurality of time-gates for imaging the object; ii) injecting a pulse of light at an injection port into said object at time t; iii) collecting light from said object at a plurality of collection ports at the selected plurality of time-gates to provide a plurality of optical signal based temporal point spread function and collecting light only for selected time gates, and not for a series of consecutive time-gates; and iv) introducing corresponding temporal delay to each one of the optical signal based temporal point spread functions for obtaining staggered optical based temporal spread point spread functions; wherein said light collection of said time-gated signals at said selected plurality of time-gates comprises: obtaining at least a first derivative of each temporal point spread function; and identifying one or more time intervals of each temporal point spread function in which a first derivative is zero at a point in said time interval thereby effecting said collection of said time-gated signals. ### Claim 2 (depends on 1) The method as claimed in claim 1 wherein said plurality of collection ports are adjacent to one another and said temporal point spread functions are identical. ### Claim 3 (depends on 2) The method as claimed in claim 2 wherein said time-gated signals span a time interval defined by an initial time and a final time which are set relative to to. ### Claim 4 (depends on 3) The method as claimed in claim 3 wherein said light collection is performed for a plurality of injection port/object/detector port geometries. ### Claim 5 (depends on 4) The method as claimed in claim 4 wherein said collection is based on one or more optical properties of said object. ### Claim 6 (depends on 4) The method as claimed in claim 4 wherein said initial time and said time-gated signals are estimated based on one or more optical properties of said object that influence propagation of said light within said object. ### Claim 7 (depends on 6) The method according to claim 6 wherein said one or more properties comprise thickness of said object. ### Claim 8 (depends on 1) The method as claimed in claim 1 wherein said time-gated signals are further selected based on an order of said derivative. ### Claim 9 (depends on 1) The method as claimed in claim 1 wherein said collection of said time-gated signals comprises: i) retrievably storing said time-gated signals such that said time-gated signals are associated with at least one predetermined characteristic of a corresponding object; and ii) matching a characteristic of a new object to be imaged with said stored predetermined characteristics to identify corresponding time-gates to be used in imaging said new object. ### Claim 10 (depends on 1) The method as claimed in claim 1 wherein said step of light collection is performed using a time-gated detector. ### Claim 11 (depends on 10) The method as claimed in claim 10 wherein the time-gated detector is an intensified charge-coupled device (ICCD) camera. ### Claim 12 (depends on 1) The method as claimed in claim 1 wherein the two or more time-gated signals are simultaneously detected at two or more time-gated detectors having a synchronized acquisition time gate. ### Claim 13 (depends on 12) The method as claimed in claim 12 wherein the step of simultaneously detecting comprises detecting said selected time-gates using a time-gated detector comprising a 2-dimensional array of pixels. ### Claim 14 (depends on 13) The method as claimed in claim 13 wherein the time-gated detector is an ICCD camera. ### Claim 15 (depends on 1) The method as claimed in claim 1 wherein the collecting of the light is achieved by providing one or more optical fibers. ### Claim 16 (depends on 15) The method as claimed in claim 15 further comprising adjusting a relative length of fibers to introduce the relative temporal delay. ### Claim 17 (depends on 16) The method as claimed in claim 16 wherein the fibers are grouped together into one or more bundles. ### Claim 18 (depends on 17) The method according to claim 17 wherein each fiber in the one or more bundles is directed to a distinct detection position of the time-gated detector or to a distinct time-gated detector. ### Claim 19 (depends on 18) The method as claimed in claim 18 wherein the one or more bundles are spatially localized such as to collect light from one or more desired areas of said object. ### Claim 20 (depends on 19) The method as claimed in claim 19 wherein the one or more bundles are coupled to one or more time-gated detectors. ### Claim 21 A system for optical imaging of a light scattering object the system comprising: i) at least one light injection port and ii) a light collecting apparatus comprising a plurality of collection ports and providing a plurality of sequential time gated optical signal based temporal point spread functions; and said light collecting apparatus collects light at a selected plurality of time-gates and not for a series of consecutive time-gates wherein said light collection apparatus collects light from an object at the plurality of collection ports and collects light of said time-gated signals at said selected plurality of times-gates by: obtaining at least a first derivative of each temporal point spread function; and identifying one or more time intervals of each temporal point spread function in which a first derivative is zero at a point in said time interval thereby effecting said collection of said time-gated signals. ### Claim 22 (depends on 21) The system according to claim 21 wherein the collection ports are adjacent to one another. ### Claim 23 (depends on 22) The system as claimed in claim 22 wherein the light collecting apparatus comprises one or more optical fibers. ### Claim 24 (depends on 23) The system as claimed in claim 23 wherein the optical delay feature comprises a difference in the relative length of the optical fibers.