Laser Doppler vibrometer

About: Laser Doppler vibrometer is a research topic. Over the lifetime, 6319 publications have been published within this topic receiving 76068 citations.

Carotid artery pulse wave measured by a laser vibrometer

Abstract: Early diagnosis of occlusive arterial diseases demands a device which sensitivity is able to resolve small differences between normal and abnormal pressure and flow pulse patterns. The present paper reports the use of a laser doppler vibrometer (LDV) in preliminary test for registration the pressure pulse. The measurements were performed in the right carotid artery of four volunteers to observe presumed typical pressure pulse patterns. LDV was used in single point mode to obtain the pressure waves in two distinct physiological situations: breathing and in apnea.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Optical measurement method and apparatus which determine a condition based on quasi-elastic-interaction

Abstract: A method and an apparatus are provided for the determination of a condition or state of an object based on quasi-elastic interaction between the object and light transmitted to the object. This light is transmitted from a light source through a diffractive optical element. The light that has interacted with the object is collected and detected. The diffractive optical element is designed in such a way that the determination of the condition or state of the object is substantially exclusively defined by the diffractive optical element and substantially independent of properties of the light source. Several diffraction patterns may be integrated in one diffractive optical element, thereby integrating several optical functions, such as lenses, beam splitters, etc. in one optical component. Use: Transit-time-velocity measurement, Doppler velocity measurement, viscoelastic measurement, differential speckle determination, differential vibrometer, distance determination apparatus, etc.

Medical laser apparatus, high powered red laser used in same, and laser resonator with non-linear output

Abstract: A laser system generates suitable laser power for use in photodynamic therapy, and particularly photodynamic therapy using dyes which undergo desired photodynamic reactions at 659 mm, ie, Purpurin The laser system generates a red output power of greater than 4 watts For the therapeutic applications, a means for delivering the red beam to therapeutic sites is provided The laser system provides for a frequency doubled solid-state laser system in which the non-linear birefringent crystal used to provide frequency doubling is mounted adjacent a flat mirror whereby losses due to walkoff of the beam caused by the crystal are minimized The laser resonant cavity defined by one flat and one other mirror, which may be stabilized by means, such as thermal lensing in the solid-state gain medium, inside the cavity A frequency doubled Nd:YAG rod in such cavity tuned to 1319 microns with a KTP frequency doubling crystal for generates an output beam at 0659 microns via type II phase matching required for photodynamic therapy in conjunction with a suitable PDT compound or dye