Abstract: Imaging a sample that includes phototransformable optical labels (“PTOLs”) with an optical system having a diffraction-limited resolution volume (DLRV), includes providing activation radiation to the PTOLs to activate a statistical subset of the PTOLs. A density of the PTOLs of the activated subset is less than an inverse of the DLRV. Excitation radiation is provided to the activated subset to excite activated PTOLs. Radiation emitted from the activated and excited PTOLs located at different focal planes of the optical system within the sample is detected with the optical system. The preceding steps are repeated one or more times, each time activating a different statistical subset of the plurality of PTOLs. Three-dimensional locations within the sample are determined, with a sub-diffraction-limited accuracy, of the activated and excited PTOLs based on the radiation emitted from the activated and excited PTOLs that is detected from the different focal planes of the optical system.

Abstract: Imaging a sample that includes phototransformable optical labels (“PTOLs”) with an optical system having a diffraction-limited resolution volume (DLRV), includes providing activation radiation to the PTOLs to activate a statistical subset of the PTOLs. A density of the PTOLs of the activated subset is less than an inverse of the DLRV. Excitation radiation is provided to the activated subset to excite activated PTOLs. Radiation emitted from the activated and excited PTOLs located at different focal planes of the optical system within the sample is detected with the optical system. The preceding steps are repeated one or more times, each time activating a different statistical subset of the plurality of PTOLs. Three-dimensional locations within the sample are determined, with a sub-diffraction-limited accuracy, of the activated and excited PTOLs based on the radiation emitted from the activated and excited PTOLs that is detected from the different focal planes of the optical system.

Abstract: Imaging a sample that includes phototransformable optical labels (“PTOLs”) with an optical system having a diffraction-limited resolution volume (DLRV), includes providing activation radiation to the PTOLs to activate a statistical subset of the PTOLs. A density of the PTOLs of the activated subset is less than an inverse of the DLRV. Excitation radiation is provided to the activated subset to excite activated PTOLs. Radiation emitted from the activated and excited PTOLs located at different focal planes of the optical system within the sample is detected with the optical system. The preceding steps are repeated one or more times, each time activating a different statistical subset of the plurality of PTOLs. Three-dimensional locations within the sample are determined, with a sub-diffraction-limited accuracy, of the activated and excited PTOLs based on the radiation emitted from the activated and excited PTOLs that is detected from the different focal planes of the optical system.

Abstract: Imaging a sample that includes phototransformable optical labels (“PTOLs”) with an optical system having a diffraction-limited resolution volume (DLRV), includes providing activation radiation to the PTOLs to activate a statistical subset of the PTOLs. A density of the PTOLs of the activated subset is less than an inverse of the DLRV. Excitation radiation is provided to the activated subset to excite activated PTOLs. Radiation emitted from the activated and excited PTOLs located at different focal planes of the optical system within the sample is detected with the optical system. The preceding steps are repeated one or more times, each time activating a different statistical subset of the plurality of PTOLs. Three-dimensional locations within the sample are determined, with a sub-diffraction-limited accuracy, of the activated and excited PTOLs based on the radiation emitted from the activated and excited PTOLs that is detected from the different focal planes of the optical system.

Abstract: An apparatus includes a position-sensitive detector to detect intensities of radiation as a function of position on the detector, and an optical system, characterized by a diffraction-limited resolution volume, adapted for imaging light emitted from activated and excited phototransformable optical labels (“PTOLs”) in a sample onto the position sensitive-detector. A first light source provides activation radiation to the sample to activate a subset of the PTOLs that are distributed in the sample with a density greater than an inverse of the diffraction-limited resolution volume of the optical system. A second light source provides excitation radiation to the sample to excite a portion of the PTOLs in the subset of the PTOLs. A controller controls one both of the activation radiation and the excitation radiation provided to the sample such that a density of PTOLs in the portion of the PTOLs is less than the inverse of the diffraction-limited resolution volume.

Abstract: An apparatus includes a position-sensitive detector to detect intensities of radiation as a function of position on the detector, and an optical system, characterized by a diffraction-limited resolution volume, adapted for imaging light emitted from activated and excited phototransformable optical labels (“PTOLs”) in a sample onto the position sensitive-detector. A first light source provides activation radiation to the sample to activate a subset of the PTOLs that are distributed in the sample with a density greater than an inverse of the diffraction-limited resolution volume of the optical system. A second light source provides excitation radiation to the sample to excite a portion of the PTOLs in the subset of the PTOLs. A controller controls one both of the activation radiation and the excitation radiation provided to the sample such that a density of PTOLs in the portion of the PTOLs is less than the inverse of the diffraction-limited resolution volume.

Abstract: An apparatus includes a position-sensitive detector to detect intensities of radiation as a function of position on the detector, and an optical system, characterized by a diffraction-limited resolution volume, adapted for imaging light emitted from activated and excited phototransformable optical labels (“PTOLs”) in a sample onto the position sensitive-detector. A first light source provides activation radiation to the sample to activate a subset of the PTOLs that are distributed in the sample with a density greater than an inverse of the diffraction-limited resolution volume of the optical system. A second light source provides excitation radiation to the sample to excite a portion of the PTOLs in the subset of the PTOLs. A controller controls one both of the activation radiation and the excitation radiation provided to the sample such that a density of PTOLs in the portion of the PTOLs is less than the inverse of the diffraction-limited resolution volume.

Abstract: An apparatus includes a position-sensitive detector to detect intensities of radiation as a function of position on the detector, and an optical system, characterized by a diffraction-limited resolution volume, adapted for imaging light emitted from activated and excited phototransformable optical labels (“PTOLs”) in a sample onto the position sensitive-detector. A first light source provides activation radiation to the sample to activate a subset of the PTOLs that are distributed in the sample with a density greater than an inverse of the diffraction-limited resolution volume of the optical system. A second light source provides excitation radiation to the sample to excite a portion of the PTOLs in the subset of the PTOLs. A controller controls one both of the activation radiation and the excitation radiation provided to the sample such that a density of PTOLs in the portion of the PTOLs is less than the inverse of the diffraction-limited resolution volume.

Abstract: An apparatus includes a position-sensitive detector to detect intensities of radiation as a function of position on the detector, and an optical system, characterized by a diffraction-limited resolution volume, adapted for imaging light emitted from activated and excited phototransformable optical labels (“PTOLs”) in a sample onto the position sensitive-detector. A first light source provides activation radiation to the sample to activate a subset of the PTOLs that are distributed in the sample with a density greater than an inverse of the diffraction-limited resolution volume of the optical system. A second light source provides excitation radiation to the sample to excite a portion of the PTOLs in the subset of the PTOLs. A controller controls one both of the activation radiation and the excitation radiation provided to the sample such that a density of PTOLs in the portion of the PTOLs is less than the inverse of the diffraction-limited resolution volume.

Abstract: First activation radiation is provided to a sample that includes phototransformable optical labels (“PTOLs”) to activate a first subset of the PTOLs in the sample. First excitation radiation is provided to the first subset of PTOLs in the sample to excite at least some of the activated PTOLs, and radiation emitted from activated and excited PTOLs within the first subset of PTOLs is detecting with imaging optics. The first activation radiation is controlled such that the mean volume per activated PTOL in the first subset is greater than or approximately equal to a diffraction-limited resolution volume (“DLRV”) of the imaging optics.

Abstract: An apparatus includes a position-sensitive detector to detect intensities of radiation as a function of position on the detector, and an optical system, characterized by a diffraction-limited resolution volume, adapted for imaging light emitted from activated and excited phototransformable optical labels (“PTOLs”) in a sample onto the position sensitive-detector. A first light source provides activation radiation to the sample to activate a subset of the PTOLs that are distributed in the sample with a density greater than an inverse of the diffraction-limited resolution volume of the optical system. A second light source provides excitation radiation to the sample to excite a portion of the PTOLs in the subset of the PTOLs. A controller controls one both of the activation radiation and the excitation radiation provided to the sample such that a density of PTOLs in the portion of the PTOLs is less than the inverse of the diffraction-limited resolution volume.

Abstract: A method of imaging with an optical system characterized by a diffraction-limited resolution volume is disclosed. In a sample that includes a plurality of phototransformable optical labels (“PTOLs”) distributed in the sample with a density greater than an inverse of the diffraction-limited resolution volume of the optical system, a first subset of the PTOLs in the sample are activated, and the density of the activated PTOLs in the first subset is less than the inverse of the diffraction-limited resolution volume. A first portion of the PTOLs in the first subset of PTOLs is excited. Radiation emitted from the activated and excited PTOLs in the first portion of PTOLs is detected with the imaging optics, and locations of activated and excited PTOLs in the first portion of PTOLs is determined with a sub-diffraction-limited accuracy based on the detected radiation emitted from the activated and excited PTOLs.