Abstract: A laser-machining system and method is disclosed for forming retainers on a suture thread. The laser system is preferably a femtosecond laser system which is capable of creating submicron features on the suture thread while preserving strength of the suture thread. The laser-machining system enables creation of retainers and self-retaining suture systems in configurations which are difficult and/or impossible to achieve using mechanical cutting technology. The laser-machining system includes a stabilization device configured to provide contactless stabilization of the suture thread during a machining operation on the suture thread.

Abstract: A laser-machining system and method is disclosed for forming retainers on a suture thread. The laser system is preferably a femtosecond laser system which is capable of creating submicron features on the suture thread while preserving strength of the suture thread. The laser-machining system enables creation of retainers and self-retaining suture systems in configurations which are difficult and/or impossible to achieve using mechanical cutting technology.

Abstract: A laser-machining system and method is disclosed for forming retainers on a suture thread. The laser system is preferably a femtosecond laser system which is capable of creating submicron features on the suture thread while preserving strength of the suture thread. The laser-machining system enables creation of retainers and self-retaining suture systems in configurations which are difficult and/or impossible to achieve using mechanical cutting technology.

Abstract: A method for improving the resolution of ultrasound images using synthetic aperture concepts. A two-dimensional image is obtained using ultrasound imaging apparatus located at a first position outside the target area and at a predetermined distance from a center point within the target area. The imaging apparatus is then moved along an arc to a new position and another two-dimensional ultrasound image is obtained. This process is repeated through up to a full 360° around the target area. Image data for each pixel is combined, calculated and transformed for all image positions to produce a highly resolved image of that pixel. The process is repeated for each pixel until all the pixels within the target area are fully resolved, thereby producing a complete, highly resolved over-all image.

Abstract: A new device for measuring the depth of surface tissue burns based on the rate at which the skin temperature responds to a sudden differential temperature stimulus. This technique can be performed without physical contact with the burned tissue. In one implementation, time-dependent surface temperature data is taken from subsequent frames of a video signal from an infrared-sensitive video camera. When a thermal transient is created, e.g., by turning off a heat lamp directed at the skin surface, the following time-dependent surface temperature data can be used to determine the skin burn depth. Imaging and non-imaging versions of this device can be implemented, thereby enabling laboratory-quality skin burn depth imagers for hospitals as well as hand-held skin burn depth sensors the size of a small pocket flashlight for field use and triage.

Abstract: A method and apparatus for determining characteristics of tissue is disclosed. The method comprises supplying optical energy to a tissue and detecting at a plurality of locations consequent energy scattered by the tissue. Analysis of the scattered energy as taught herein provides information concerning the properties of the tissue, specifically information related to the fat and lean content and thickness of the tissue. The apparatus comprises a light source adapted to deliver optical energy to a tissue. A plurality of detectors can be mounted at different positions relative to the source to detect energy scattered by the tissue. A signal processor as taught herein can determine characteristics of the tissue from the signals from the detectors and locations of the detectors, specifically information related to the fat and lean content and thickness of the tissue.

Abstract: An apparatus and method are disclosed for optically sensing motion in a microelectromechanical system (also termed a MEMS device) formed by surface micromachining or LIGA. The apparatus operates by reflecting or scattering a light beam off a corrugated surface (e.g. gear teeth or a reference feature) of a moveable member (e.g. a gear, rack or linkage) within the MEMS device and detecting the reflected or scattered light. The apparatus can be used to characterize a MEMS device, measuring one or more performance characteristic such as spring and damping coefficients, torque and friction, or uniformity of motion of the moveable member. The apparatus can also be used to determine the direction and extent of motion of the moveable member; or to determine a particular mechanical state that a MEMS device is in. Finally, the apparatus and method can be used for providing feedback to the MEMS device to improve performance and reliability.

Abstract: A microengine uses two synchronized linear actuators as a power source and converts oscillatory motion from the actuators into constant rotational motion via direct linkage connection to an output gear or wheel. The microengine provides output in the form of a continuously rotating output gear that is capable of delivering drive torque at a constant rotation to a micromechanism. The output gear can have gear teeth on its outer perimeter for directly contacting a micromechanism requiring mechanical power. The gear is retained by a retaining means which allows said gear to rotate freely. The microengine is microfabricated of polysilicon on one wafer using surface micromachining batch fabrication.

Abstract: A method and apparatus maps a Gaussian beam into a beam with a uniform irradiance profile by exploiting the Fourier transform properties of lenses. A phase element imparts a design phase onto an input beam and the output optical field from a lens is then the Fourier transform of the input beam and the phase function from the phase element. The phase element is selected in accordance with a dimensionless parameter which is dependent upon the radius of the incoming beam, the desired spot shape, the focal length of the lens and the wavelength of the input beam. This dimensionless parameter can also be used to evaluate the quality of a system. In order to control the radius of the incoming beam, optics such as a telescope can be employed. The size of the target spot and the focal length can be altered by exchanging the transform lens, but the dimensionless parameter will remain the same. The quality of the system, and hence the value of the dimensionless parameter, can be altered by exchanging the phase element.

Abstract: An imaging apparatus and method for use in presenting composite two dimensional and three dimensional images from individual ultrasonic frames. A cross-sectional reconstruction is applied by using digital ultrasound frames, transducer orientation and a known center. Motion compensation, rank value filtering, noise suppression and tissue classification are utilized to optimize the composite image.

Abstract: An optical apparatus and method for measuring the percent of open area of a perforated sheet. The apparatus and method based on Fourier optics uses a light detector which measures only a small central portion of the light in a Fraunhofer diffraction pattern of the perforated sheet. The ratiometer offers both accurancy and speed in the measuring of the percent of open area while avoiding diffraction problems which are characteristic with arrays of small holes in the perforated sheet. Also, the invention can be used with both opaque and translucent materials.

Abstract: An apparatus and method of converting an image on a transparency such as photographic film to line art on a recording medium so that the line art may be microfilmed. The invention, through the use of optical processing techniques, greatly simplifies the conversion of continuous tone and half tone photographs to line art which heretofore had to be manually traced prior to microfilming the line art.

Abstract: An infrared window transmittance tester utilized for measuring the transmission of windows used in military and commercial infrared imaging systems.