An acousto-optic transducer comprises a graphene resonator, a substrate, an entry window and an exit window. The graphene resonator bears at least one donor molecule. The substrate bears at least one acceptor molecule. The graphene resonator is responsive to sound to bring the at least one donor molecule within range of the at least one acceptor molecule for Förster resonance energy transfer from the at least one donor molecule to the at least one acceptor molecule to take place. The entry window is arranged to permit incoming light to fall on the at least one donor molecule. The exit window is arranged to allow light emitted by the at least one acceptor molecule to leave the acousto-optic transducer. Thus, the acousto-optic transducer can function as a passive device using only energy derived from ambient light to convert sound into light.

Method for examining bone in vivo, comprises obtaining a laser beam; modulating the laser beam to insert therein photoacoustic frequencies including optical frequencies and acoustic frequencies, the acoustic frequencies being able to give rise to acoustic waves; directing the modulated beam at a bone to cause acoustic waves resulting from the beam to travel through the bone; analyzing received signals from the bone including signals resulting from the acoustic waves, to determine a mineral density and a bone quality for said bone, and thus obtain in-vivo data that can be of assistance to a doctor when diagnosing osteoporosis.

A method is disclosed for generating sinograms by sampling a plurality of transducers acoustically coupled with the surface of a volume of tissue over a period of time after a light pulse at one wavelength, and after another light pulse at a different wavelength, and for processing those sinograms, reconstructing at least two optoacoustic images from the two sinograms, processing the two optoacoustic images to generate two envelope images and generating a parametric map from information in the two envelope images. In an embodiment, motion and tracking are determined to align the envelope images. In an embodiment, at least a second parametric map is produced from information in the same two envelope images. In an embodiment an ultrasound image is also acquired, and the parametric map is coregistered with and overlayed upon the ultrasound image, and then displayed.

A catheter system includes a catheter. The catheter includes a catheter tip and an ultrasound assembly at least partially positioned within the catheter tip. The ultrasound assembly includes a first optical fiber coupled to an optical-to-ultrasound transducer and a second optical fiber coupled to an ultrasound-to-optical transducer. The optical-to-ultrasound transducer is configured to generate an ultrasound signal in response to a pulsed optical signal. The ultrasound-to-optical transducer is configured to generate an optical signal in response to a received ultrasound signal.

A first signal is generated with a first light detector in response to an ultrasound signal encountering a first measurement beam. A second signal is generated with a second light detector in response to the ultrasound signal encountering a second measurement beam. The second measurement beam propagates through the sample and the first measurement beam propagates outside the sample.

A method is disclosed for generating sinograms by sampling a plurality of transducers acoustically coupled with the surface of a volume of tissue over a period of time after a light pulse at one wavelength, and after another light pulse at a different wavelength, and for processing those sinograms, reconstructing at least two optoacoustic images from the two sinograms, processing the two optoacoustic images to generate two envelope images and generating a parametric map from information in the two envelope images. In an embodiment, motion and tracking are determined to align the envelope images. In an embodiment, at least a second parametric map is produced from information in the same two envelope images. In an embodiment an ultrasound image is also acquired, and the parametric map is coregistered with and overlayed upon the ultrasound image, and then displayed.

Medical imaging systems for use in conjunction with an endoscope are described. Generally, the medical imaging system includes an illumination source configured to generate illuminating photons. The illuminating photons are transmitted to one or more filters configured to filter a first plurality of illuminating photons and generate a first plurality of filtered photons comprising a first passband wavelength and a second plurality of filtered photons comprising a second passband wavelength. A sample is then illuminated with the first plurality of filtered photons and the second plurality of filtered photons to generate a first plurality of interacted photons and a second plurality of interacted photons. One or more detectors are configured to detect the first plurality of interacted photons and the second plurality of interacted photons and generate one or more image data sets.

An image pixel array captures and infrared image of an interference between an imaging signal and a reference wavefront. A display pixel array generates an infrared holographic imaging signal and the image pixel array receives the infrared imaging signal through the display pixel array.

This disclosure provides systems and methods for mapping and/or measuring a mechanical property of a medium. The mechanical property can be measured by Brillouin spectroscopy. The systems and methods can include a three-dimensional imaging modality that is co-registered with a Brillouin probe beam of a Brillouin spectrometer. The three-dimensional imaging modality can be optical coherence tomography or Scheimpflug camera imaging.

Systems and methods are provided for performing OCT vibrography based on the synchronization of components of the OCT vibrography system. An A-scan trigger is employed to synchronize the operation of the scanning subsystem that scans the sample beam and an acoustic stimulus source that generates an acoustic stimulus for vibrographic measurements. The acoustic stimulus source is controlled such that when the scanning subsystem dwells on an imaging line selected for vibrography measurements, the acoustic stimulus is generated over a plurality of A-scans and the phase of the acoustic stimulus is locked to the A-scan trigger, such that the phase of the acoustic stimulus is incrementally modified with each A-scan. The accumulation of the acoustic phase is therefore synchronized to the A-scan trigger. The synchronization, providing synchronized acoustic phase evolution during each acoustic phase waveform cycle, permits the use of the OCT vibrography system for simultaneous anatomical and functional imaging.