195results about How to "Minimize reflection" patented technology

A collapsible ultrasonic reflector incorporates a gas-filled reflector balloon, a liquid-filled structural balloon an ultrasonic transducer disposed within the structural balloon. Acoustic energy emitted by the transducer is reflected by a highly reflective interface between the balloons. In a cardiac ablation procedure, the ultrasonic energy is focused into an annular focal region to ablate cardiac tissue extending in an annular path along the wall. Devices for stabilizing the balloon structure and for facilitating collapse and withdrawal of the balloon structure are also disclosed.

Systems and methods are provided for applying a high frequency voltage in the presence of an electrically conductive fluid to create a relatively low-temperature plasma for ablation of tissue adjacent to, or in contact with, the plasma. In one embodiment, an electrosurgical probe or catheter is positioned adjacent the target site so that one or more active electrode(s) are brought into contact with, or close proximity to, a target tissue in the presence of electrically conductive fluid. High frequency voltage is then applied between the active electrode(s) and one or more return electrode(s) to non-thermally generate a plasma adjacent to the active electrode(s), and to volumetrically remove or ablate at least a portion of the target tissue. The high frequency voltage generates electric fields around the active electrode(s) with sufficient energy to ionize the conductive fluid adjacent to the active electrode(s). Within the ionized gas or plasma, free electrons are accelerated, and electron-atoms collisions liberate more electrons, and the process cascades until the plasma contains sufficient energy to break apart the tissue molecules, causing molecular dissociation and ablation of the target tissue.

What is disclosed is a 3-D laser measurement system, including a mirror continuously rotatable about a rotation axis which extends, e.g., in parallel or coaxial with a measuring beam emitted by an optical emitter and impinging on the mirror.

An improved optical fiber comprising a waveguide with an input for coupling focused laser energy into the waveguide and communicating electromagnetic radiation in a propagation direction to an internally reflective tip of the waveguide, a tissue contacting surface wherein the light path from the reflecting surface to the transmitting surface in substantially homogenous in refractive index and cooled by fluid flow. In minimizing the variations in refractive index within the lateral light path, while providing active cooling directly below the tissue contact surface, the invention prevents internal reflections and beam distortion and greatly improves the efficiency and durability of the laterally directing probe. Free rotation of the tissue contact surface, about the lateral tip, may be provided and tissue vaporization efficiency may be improved by providing a morcellating tool on the tissue contact surface.

A sub-reflector for a dish reflector antenna with a waveguide supported sub-reflector. The sub-reflector formed from a dielectric block, concentric about a longitudinal axis. The dielectric block having a first diameter waveguide junction portion adapted for coupling to an end of the waveguide and a sub-reflector surface coated with an RF reflective material having a periphery with a second diameter larger than the first diameter. A leading cone surface extends from the waveguide junction portion to the second diameter at an angle. The sub-reflector surface and the leading cone surface having a plurality of non-periodic perturbations concentric about the longitudinal axis.

A display system for suspending visuals for exhibit, training or advertising made up of an assembly of commercially available items, and used to display a banner or sign in a manner that is particularly useful on the set of a local television station. One embodiment has elastic cords, slotted tubular members, floor anchors, cord hooks, cord locks and a ceiling interface. When a rigid sign is situated with its bottom edge positioned in the lower tubular member slot and its top edge in the upper tubular member slot, the sign is suspended for viewing. In another embodiment, horizontal rods are supported by two tubular members with portions of the rods extended beyond the ends the tubular members. Several banner clips are used to clip a banner to the portions of the rods extending beyond the ends of the tubular members to suspend the banner for viewing. Other embodiments incorporate more than one set of either slotted tubular members or rod-supporting tubular members, or a combination of slotted tubular members and rod-supporting tubular members.

An improved optical fiber comprising a waveguide with an input for coupling focused laser energy into the waveguide and communicating electromagnetic radiation in a propagation direction to an internally reflective tip of the waveguide, a tissue contacting surface wherein the light path from the reflecting surface to the transmitting surface in substantially homogenous in refractive index and cooled by fluid flow. In minimizing the variations in refractive index within the lateral light path, while providing active cooling directly below the tissue contact surface, the invention prevents internal reflections and beam distortion and greatly improves the efficiency and durability of the laterally directing probe. Free rotation of the tissue contact surface, about the lateral tip, may be provided and tissue vaporization efficiency may be improved by providing a morcellating tool on the tissue contact surface.

A proximity sensor can be used with a device such as a monitoring tag or portable tracking device that relies on GPS signals or other radio-frequency signals. The proximity sensor determines if the signals are being deliberately blocked by an object such as metal foil being placed in proximity to the device. The sensor includes an oscillator, a directional coupler and an antenna. A third port of the directional coupler acts as a coupled port when RF power that has been transmitted by the antenna is reflected back to the antenna by a blocking object. The reflected RF power passes along a main line of the directional coupler and a proportion is coupled to the third port. A detector provides an alert if the magnitude of the power of the transmit signal that is reflected back to the antenna in the form of a receive signal exceeds a threshold.

Lithographic apparatus providing a patterned beam of radiation in which radiation that is linearly polarized in a first direction has a first pattern and radiation that is linearly polarized in an orthogonal direction has a second pattern.

The sensor comprises a beam of electromagnetic radiation projecting across a gap between the stationary member and the translating member, a reference detector having a reference FOV and a signal detector having a signal FOV. The sensor is to be mounted on the stationary member. The electromagnetic radiation beam, the reference FOV and the signal FOV intersect in a volume including the gap, and the gap is calculated from the reflected electromagnetic radiation received by the reference and signal detectors. The gap can be determined from a ratio between a rise time in the signal pulse and a rise time in the reference pulse, or a ratio between a fall time in the signal pulse and a fall time in the reference pulse, or a ratio between a delay time in the signal pulse and a delay time in the reference pulse, among other features.