53 results about "Focal volume" patented technology

A shock wave applicator includes a shock wave generator and an asymmetrical reflector portion in a housing. Asymmetry of the reflector portion is combined with one or more wave generators to produce a variety of focal volumes and wave fronts for medical treatment.

This invention is related to a flow fluorometric device and method employing a two-photon excitation and/or confocal optical set-up. The optical set-up of this invention is optimal for counting small fluorescent biological particles. The active focal volume is diffraction-limited and consequently much smaller than the volume of the flow channel. The excitation and detection concept has been found very efficient for rejection of the background signal. An objective lens with large numerical aperture for focusing the laser and for collecting the fluorescence is used and this restricts the active volume of measurement to a diffraction-limited volume which approximately corresponds to a volume of femtoliter. This volume is significantly smaller than the detection volume of ordinary flow cytometry.

A method for quantitatively measuring nucleic acid amplification reactions, especially the polymerase chain reaction, employing microparticles as hybridization solid phase, a probe sequence labeled with a fluorescent label and a fluorescence detection system which is based on two-photon fluorescence excitation, contacting all the amplification reaction components and the solid phase simultaneously in a closed cuvette, performing the amplification reactions in the same cuvette, focusing a two-photon exciting laser beam into the cuvette during the amplification cycles and measuring the fluorescence signal emitted by the microparticles from one particle at a time when they randomly float through the focal volume of the laser beam. The features of this invention allow a method and device for performing a fast quantitative nucleic acid amplification assay of single or multiple target sequences in a very small closed sample volume.

Various embodiments include a method of producing chemically pure and stably dispersed metal and metal-alloy nanoparticle colloids with ultrafast pulsed laser ablation. A method comprises irradiating a metal or metal alloy target submerged in a liquid with ultrashort laser pulses at a high repetition rate, cooling a portion of the liquid that includes an irradiated region, and collecting nanoparticles produced with the laser irradiation and liquid cooling. The method may be implemented with a high repetition rate ultrafast pulsed laser source, an optical system for focusing and moving the pulsed laser beams, a metal or metal alloy target submerged in a liquid, and a liquid circulating system to cool the laser focal volume and collect the nanoparticle products. By controlling various laser parameters, and with optional liquid flow movement, the method provides stable colloids of dispersed metal and metal-alloy nanoparticles. In various embodiments additional stabilizing chemical agents are not required.

A laser direct write method creates true three dimensional structures within photocerams using an focused pulsed ultraviolet laser with a wavelength in a weakly absorbing region of the photoceram material. A critical dose of focused laser UV light selectively exposes embedded volumes of the material for subsequent selective etching. The photoceram material exposure is nonlinear with the laser fluence and the critical dose depends on the square of the per shot fluence and the number of pulses. The laser light is focused to a focal depth for selective volumetric exposure of the material within a focal volume within the remaining collateral volumes that is critically dosed for selecting etching and batch fabrication of highly defined embedded structures.

A diagnostic method and associated system includes the steps of exposing at least one sample location with excitation radiation through a single optical waveguide or a single optical waveguide bundle, wherein the sample emits emission radiation in response to the excitation radiation. The same single optical waveguide or the single optical waveguide bundle receives at least a portion of the emission radiation from the sample, thus providing co-registration of the excitation radiation and the emission radiation. The wavelength of the excitation radiation and emission radiation is synchronously scanned to produce a spectrum upon which an image can be formed. An increased emission signal is generated by the enhanced overlap of the excitation and emission focal volumes provided by co-registration of the excitation and emission signals thus increasing the sensitivity as well as decreasing the exposure time necessary to obtain an image.

The method of stimulating a tissue of a subsurface organ is disclosed. The method has the steps of activating an acoustic shock wave generator or source to emit acoustic shock waves; and subjecting the tissue to the acoustic shock waves stimulating said tissue wherein the tissue is positioned within a path of the emitted shock waves and away from a geometric focal volume or point of the emitted shock waves. In one embodiment the emitted shock waves are divergent or near planar. In another embodiment the emitted shock waves are convergent having a geometric focal volume of point at a distance of at least X from the source, the method further comprising positioning the tissue at a distance less than the distance X from the source. The subsurface organ is a tissue having cells. The tissue is a part of the incretin system. The subsurface organ is preferably the pancreas of a diabetic or at risk diabetic patient. The treatment stimulates the pancreatic tissue by an analgesic effect on the nerves and a stimulation of the insulin producing islets.

A method for measuring the end point and for monitoring the real time kinetics of a bioaffinity reaction in biological fluids and suspensions, employing microparticles as bioaffinity binding solid phase, biospecific reagent labelled with a fluorescent label and a fluorescence detection system which is based on two-photon fluorescence excitation, contacting the analyte, the labelled reagent and the solid phase simultaneously, focusing a two-photon exciting laser beam into the reaction suspension and measuring the fluorescence signal emitted by the microparticles from one particle at a time when they randomly float through the focal volume of the laser beam. In this method the signal is monitored kinetically to obtain information about the analyte concentration before the reaction approaches the highest point of the response. Since the growth rate of the signal intensity is directly proportional to the analyte concentration, the analyte concentration can be predicted in the initial phase of the reaction. The growth rate monitoring also predicts whether the analyte concentration is higher than the binding capacity of the reagent and whether the reaction will be continued over the highest point of the response curve.

Disclosed is a method of producing a chemically pure and stably dispersed organic nanoparticle colloidal suspension using an ultrafast pulsed laser ablation process. The method comprises irradiating a target of an organic compound material in contact with a poor solvent with ultrashort laser pulses at a high repetition rate and collecting the nanoparticles of the organic compound produced. The method may be implemented with a high repetition rate ultrafast pulsed laser source, an optical system for focusing and moving the pulsed laser beam, an organic compound target in contact with a poor solvent, and a solvent circulating system to cool the laser focal volume and collect the produced nanoparticle products. By controlling various laser parameters, and with optional poor solvent flow movement, the method provides stable colloids of dispersed organic nanoparticles in the poor solvent in the absence of any stabilizing agents.

A microscopy imaging system includes a first light source for providing a first train of pulses at a first center optical frequency ω₁, a second light source for providing a second train of pulses at a second center optical frequency ω₂, a modulator system, an optical detector, and a processor. The modulator system is for modulating a beam property of the second train of pulses at a modulation frequency f of at least 100 kHz. The optical detector is for detecting an integrated intensity of substantially all optical frequency components of the first train of pulses from the common focal volume by blocking the second train of pulses being modulated. The processor is for detecting, a modulation at the modulation frequency f, of the integrated intensity of the optical frequency components of the first train of pulses to provide a pixel of an image for the microscopy imaging system.

Thermal 3-D microstructuring of photonic structures is provided by depositing laser energy by non-linear absorption into a focal volume about each point of a substrate to be micromachined at a rate greater than the rate that it diffuses thereout to produce a point source of heat in a region of the bulk larger than the focal volume about each point that structurally alters the region of the bulk larger than the focal volume about each point, and by dragging the point source of heat thereby provided point-to-point along any linear and non-linear path to fabricate photonic structures in the bulk of the substrate. Exemplary optical waveguides and optical beamsplitters are thermally micromachined in 3-D in the bulk of a glass substrate. The total number of pulses incident to each point is controlled, either by varying the rate that the point source of heat is scanned point-to-point and/or by varying the repetition rate of the laser, to select the mode supported by the waveguide or beamsplitter to be micromachined. A wide range of passive and active optical and other devices may be thermally micromachined.

Methods and apparatus for concentrating light into a specified focal volume and for collecting light from a specified volume. Incident light is coupled through a plurality of successive transmissive asymmetric microstructure elements. The succession of transmissive asymmetric microstructure elements may be designed by representing an electromagnetic field as a linear combination of eigenmodes of one of the succession of transmissive asymmetric microstructure elements. The asymmetric microstructure elements are represented as a plurality of mesh lattice units and eigenmode solutions to Maxwell's equations are obtained for each mesh lattice unit subject to consistent boundary conditions. S-matrix formalism is employed to calculate a field output and weighting coefficients for the eigenmodes are selected to achieve a specified set of field output characteristics.

The method of stimulating a plant substance is disclosed. The method has the steps of activating a pressure pulse or an acoustic shock wave generator or source to emit pressure pulse or acoustic shock waves; and subjecting the plant substance to the pressure pulse or acoustic shock waves stimulating said plant substance wherein the substance is positioned within a path of the emitted shock waves. In one embodiment the emitted pressure pulse or shock waves are divergent or near planar. In another embodiment the emitted shock waves are convergent having a geometric focal volume of point at a distance of at least X from the source, the method further comprising positioning the substance at a distance less than the distance X from the source. The substance is a plant tissue having cells. The tissue can be a seed, zygotic embryo or somatic embryogenic culture of somatic embryos of plants. The plant may be a vegetable, tree, shrub or tuber. The tissue may be a part of the root system, a part of the stem system or a part of the leaf system. The method of stimulating includes activating the cells within the treated tissue thereby releasing growth factor proteins or other chemical compositions promoting growth and accelerating germination or plant growth.

Laser capture microdissection occurs where the transfer polymer film is placed on a substrate overlying visualized and selected cellular material from a sample for extraction. The transfer polymer film is focally activated (melted) with a pulse brief enough to allow the melted volume to be confined to that polymer directly irradiated. This invention uses brief pulses to reduce the thermal diffusion into surrounding non-irradiated polymer, preventing it from being heated hot enough to melt while providing sufficient heat by direct absorption in the small focal volume directly irradiated by the focused laser beam. This method can be used both in previously disclosed contact LCM, non contact LCM, using either condenser-side (or beam passes through polymer before tissue) or epi-irradiation (or laser passes through tissue before polymer). It can be used in configuration in which laser passes through tissue before polymer with and without an additional rigid substrate. In its preferred configuration it uses the inertial confinement of the surrounding unmelted thermoplastic polymer (and the overlying rigid substrate) to force expansion of the melted polymer into the underlying tissue target. Utilizing the short pulse protocol, the targeted and extracted material can have a diameter equal to or smaller than the exciting beam.