A method of acousto-optic imaging may include receiving a first signal from a first sub-aperture of a sensor array. The first sub-aperture may comprise one or more array elements of a first type. The method may further include receiving a second signal from a second sub-aperture of the sensor array. The second sub-aperture may comprise one or more array elements of a second type different from the first type. In some variations, the first type of array element may be an acoustic transducer (e.g., piezoelectric transducer) and/or the second type of array element may be an optical sensor (e.g., optical resonator such as a whispering gallery mode (WGM) resonator). The method may further include combining the first signal and the second signal to form a synthesized aperture for the sensor array.

A system and method for measuring biomechanical properties of tissues without external excitation are capable of measuring and quantifying these parameters of tissues in situ and in vivo. The system and method preferably utilize a phase-sensitive optical coherence tomography (OCT) system for measuring the displacement caused by the intrinsic heartbeat. The method allows noninvasive and nondestructive quantification of tissue mechanical properties. Preferably, the method is used to detect tissue stiffness and to evaluate its stiffness due to intrinsic pulsatile motion from the heartbeat. This noninvasive method can evaluate the biomechanical properties of the tissues in vivo for detecting the onset and progression of degenerative or other diseases and evaluating the efficacy of therapies.

A system and method of detecting acoustic waves including directing a continuous-wave source laser beam to an optical resonator that is impinged by acoustic the waves. Optionally, the source laser beam can propagate through the optical resonator, thereby generating a propagated laser beam. Using an interferometer, the acoustic waves can be detected by monitoring transients in an optical phase of the propagated laser beam.

An apparatus for optical detection of ultrasound includes one or more optical resonators (OR—200), one or more optical passive-demodulation interferometers (OPDI—22), and one or more respective electro-optical readout circuits (EORC—24). The one or more optical resonators (OR) are configured to modulate respective carrier frequencies of optical signals indicative of US waves impinging thereon. The one or more OPDI are implemented in one or more photonic integrated circuits (PIC), wherein each OPDI is configured to demodulate the optical signal output by the respective OR, so as to generate a respective intensity-modulated optical signal. Each OPDI includes an interferometer (32) having imbalanced arms (323, 325) that are recombined using an optical hybrid (34). The one or more respective EORC are each configured to measure the intensity demodulated optical signal produced by the respective OPDI, and to output a respective electrical signal.

A fibrosis measurement device that measures fibrosis of a biological tissue non-invasively includes: a sound wave emitter that performs scanning over a surface of a biological tissue as a measurement object to emit sound waves; an electromagnetic wave receiver that receives an electromagnetic wave generated at each location of a biological tissue irradiated with sound waves; a signal extractor that extracts a signal indicating physical property, based on at least one selected from a group including the amplitude, phase, and frequency of an electromagnetic wave received by the electromagnetic wave receiver; an imaging unit that images signals extracted by the signal extractor; and an area comparison unit that compares the area of a portion of the two-dimensional image in which signals indicating a property are displayed, with an area corresponding to a preset threshold of the strength of the signals.

The invention relates to a method of the noninvasive optical in-vivo measurement of properties of flowing blood in a blood vessel within a body, for example for determining the concentration of blood constituents, wherein the body is irradiated with ultrasound radiation at an ultrasound frequency (f.sub.US) in order to label a blood vessel, the body with the blood vessel is illuminated with light with at least one light wavelength and the back-scattered light is detected with a detector, the light component backscattered by the body outside of the blood vessel is modulated by a frequency (f.sub.MG) that corresponds to the frequency (f.sub.US) of the ultrasound radiation, and the light component backscattered inside the blood vessel is modulated due to the Doppler effect in flowing blood with a frequency (f.sub.MB) that is shifted by the Doppler shift (f.sub.D) with respect to the frequency (f.sub.US) of the ultrasound radiation, and an evaluation device extracts the signal component modulated by the shifted frequency (f.sub.MB) from the detector signal measured at the detector.

Provided is an ultrasound therapy system for treating a joint by providing a focused ultrasound wave to a bone surface as an affected part, and which has a temperature monitoring function for controlling irradiation intensity. The ultrasound therapy system includes a focused ultrasound wave providing unit provided on skin and configured to radiate the focused ultrasound wave to the affected part, and a temperature detecting unit configured to measure a temperature of the affected part. The temperature detecting unit includes an electromagnetic wave measuring unit configured to measure intensity of an electromagnetic wave radiated from the bone surface, and an analyzing unit configured to analyze change of the electromagnetic wave of the electromagnetic wave measuring unit to provide the temperature of the affected part. The analyzing unit provides the temperature of the affected part from electromagnetic change between a pair of reference waves for electromagnetic change which correspond to a pair of an emitted wave of the focused ultrasound wave provided from the focused ultrasound wave providing unit and a reflected wave from the bone surface and which are measured at the electromagnetic wave measuring unit with a time delay.

A system and method for measuring biomechanical properties of tissues without external excitation are capable of measuring and quantifying these parameters of tissues in situ and in vivo. The system and method preferably utilize a phase-sensitive optical coherence tomography (OCT) system for measuring the displacement caused by the intrinsic heartbeat. The method allows noninvasive and nondestructive quantification of tissue mechanical properties. Preferably, the method is used to detect tissue stiffness and to evaluate its stiffness due to intrinsic pulsatile motion from the heartbeat. This noninvasive method can evaluate the biomechanical properties of the tissues in vivo for detecting the onset and progression of degenerative or other diseases and evaluating the efficacy of therapies.

The invention comprises a method and apparatus for sampling optical pathways having a common tissue depth, such as a maximum mean depth of penetration in the dermis, with a common detector of a person for analysis in a noninvasive analyte property determination system, comprising the steps of: probing skin with a range of illumination zone-to-detection zone distances with at least two wavelength ranges, which optionally overlap, and detecting, using a common detector, illumination zone-to-detection zone distances having mean optical pathways probing the common tissue layer, such as without the mean optical pathways entering the subcutaneous fat layer of the person. Optionally, the skin tissue layers are modulated and/or treated via tissue displacement before and/or during data collection.

Techniques for imaging are disclosed. In one example, the disclosure is directed to a sensor positioned on an elongate optical fiber. The sensor comprises a plurality of blazed Bragg gratings configured to generate acoustic energy for imaging a region in response to a first optical signal, an interferometer configured to sense acoustic energy from the region and to provide a responsive second optical signal, the interferometer including a first fiber Bragg grating (FBG) and a second FBG, wherein the plurality of blazed Bragg gratings are positioned between the first and second FBGs.