Drexel University

Thomas Jefferson University

Medelex, Inc.

Peter A Lewin

Afshin S Daryoush

Mahmoud A El-Sherif

Rupa Gopinath Minasamudram

Paul Walinsky

John M Reid

Sorin Siegler

Sorin Adrian

Richard C Hayes

The fiber optic probe detects changes in ultrasound pressure in an immersion medium such as a liquid, a gas, or a solid, where the system includes an optical fiber probe having a fiber of the probe has a highly doped (or regular) core with a diameter in the range 5 to 10 &#x3bc;m and a clad diameter equal to or more than 50 &#x3bc;m; and the optical fiber tip has been modified in a D-shaped (or V-shaped) structure where the clad material has been removed from one side of the cylindrical fiber to the surface of the fiber core; then, this modified region of the fiber is coated, with a very thin layer of a metallic material, ranging from 3 to 10 nm.

Highly doped d-shaped fiberoptic probe for hydrophone applications

A sensing method is based on using a special fiberoptic probe for detection of acoustic/ultrasound pressure in an immersion medium. The developed system is highly sensitive in detecting ultrasound waves up to 100 MHz, for imaging of micro structures and more. For applications up to 100 MHz, without spatial averaging corrections, the probe tip is modified by reducing the fiber diameter to 7 um or less. Also, to maximize acousto-optic interaction, the probe tip, not just its end face, may be coated with a thin layer of metallic material. This thin film coating satisfies partial transparency of the metallic coating. The coating thickness may range from 2 nm to 10 nm or others depending on the type of the coating material. The probe detects the pressure of acoustic and/or ultrasound waves propagating within an immersion medium, whenever the probe tip is immersed inside the medium, and having a reasonable immersion contact surface.

Fiber optic hydrophone sensors and uses thereof

Disclosed is detecting changes in pressure in a medium, with an optical fiber having a core diameter at an immersion surface contact of the fiber of less than 10 &#x3bc;m; a layer of material deposited on said end of the fiber, the material being of a thickness of from about 2 nm to about 10 nm. Also disclosed is detecting pressure waves in a medium comprising: contacting the medium with a fiber optic, the fiber integrated with a light source and a detector, the fiber optic having a diameter of less than 10 &#x3bc;m at an immersion surface contact of the fiber; providing a thin layer of material on the immersion surface contact, wherein said thin layer of material is of a thickness in a range of from about 2 nm to about 10 nm; and detecting Fresnel back reflections from the immersion end of the fiber.

An acoustic catheter reduces transmission losses and unwanted heating of the transmission member by driving the catheter a rotary motor. The catheter includes an elongated body and a shaft extending longitudinally therethrough. The shaft is adapted for coupling to a rotary motor. A rotary-to-axial motion converter is coupled to the shaft at distal end of the catheter, for converting rotary shaft motion into axial acoustic motion. In one embodiment, the rotary-to-axial motion converter includes a swash plate driven by the shaft. The swash plate defines a surface which, at an angularly fixed reference point, moves axially in response to the rotary motion of the swash plate. A follower bears on the swash plate, for moving axially in response to axial motion of the follower. The follower includes a projection bearing on the swash plate and a spring urging the follower toward the swash plate. In one embodiment, the swash plate has a sinusoidal surface, while another embodiment has notches cut into the surface. The follower generates acoustic energy within a fluid medium, and may have a concave fluid coupling surface. To aspirate the material removed from arterial walls, one or more lumens extend through the catheter. In a particular embodiment of the invention, the rotary shaft is hollow, in order to allow a guide wire to pass therethrough.

Acoustic catheter with rotary drive

Novel intravascular, ultrasonic imaging catheters are provided which utilize thin layers of a flexible plastic material, such as PVDF, which can be spot polarized in active regions which are to serve as piezoelectric transducers. Thin layer metallic electrodes are deposited on opposing surfaces of these active regions. Strips of the appropriately configured material also having shielding and backing and/or core forming portions are spiral wound into a completed catheter. Alternatively, the catheters are fabricated from extruded PVDF tubing which may be formed around a central core which carries those electrodes which are to contact the inner surface of the extruded tube.

Growing community of inventors

Wyndmoor, PA, United States of America

Peter A Lewin