Abstract: The present disclosure describes a fast-scanning optical-resolution photoacoustic (fsOR-PAE) endoscope for imaging vasculature within tissues in vivo that includes an ultrasonic transducer and a scanning mirror within a lumen of an elongate casing. The scanning mirror is configured to direct the laser pulses from the pulsed laser source to a focal spot outside the casing in a scanning pattern via an imaging window formed in the casing. The scanning mirror is further configured to direct a plurality of photoacoustic signals from the focal spot to the ultrasonic transducer via the imaging window.

Abstract: Apparatus and methods for measuring infrared absorption of a sample that includes delivering a pulse of infrared radiation to a region of the sample, delivering pulses of radiation of a shorter wavelength than infrared radiation to a sub-region within the region, and using one or more properties of the induced photoacoustic signals to create a signal indicative of infrared absorption of the sub-region of the sample.

Abstract: A pressing position and pressure measurement method based on PPG (photoplethysmographic) imaging, which only needs a camera to locate multiple pressing areas and measure corresponding pressure values without a pressure sensor. Before the measurement starts, only a simple calibration work is needed. With the gradual increase of the pressing pressure, the characteristics of PPG signals corresponding to diastolic pressure and systolic pressure will disappear one by one, and by recording two sets of pressure values and the corresponding PPG signal intensity values, the relation curve of the pressure versus blood perfusion changes can be fitted. Through this relation curve, the pressure values corresponding to different blood PPG signal intensities can be obtained. Different from the traditional technical route, the present disclosure provides a non-contact measurement method for determining the pressing location and measuring the pressure through a camera.

Abstract: The present disclosure describes a fast-scanning optical-resolution photoacoustic (fsOR-PAE) endoscope for imaging vasculature within tissues in vivo that includes an ultrasonic transducer and a scanning mirror within a lumen of an elongate casing. The scanning mirror is configured to direct the laser pulses from the pulsed laser source to a focal spot outside the casing in a scanning pattern via an imaging window formed in the casing. The scanning mirror is further configured to direct a plurality of photoacoustic signals from the focal spot to the ultrasonic transducer via the imaging window.

Abstract: In various aspects, a photoacoustic endoscopic probe and methods for measuring a hydration of a connective tissue in vivo using the photoacoustic endoscopic probe are disclosed.

Abstract: Apparatus and methods for measuring infrared absorption of a sample that includes delivering a pulse of infrared radiation to a region of the sample, delivering pulses of radiation of a shorter wavelength than infrared radiation to a sub-region within the region, and using one or more properties of the induced photoacoustic signals to create a signal indicative of infrared absorption of the sub-region of the sample.