1256 results about "Intensity modulation" patented technology

A method for determining a radiation treatment plan for a radiotherapy system providing multiple individual rays of intensity modulated radiation iteratively optimized the fluence of an initial set of such rays by a function that requires knowledge of only the prescribed dose and the dose resulting from the particular ray fluences. In this way, the need to store individual dose distributions of each ray are eliminated.

PCT No. PCT/US95/02155 Sec. 371 Date Dec. 22, 1997 Sec. 102(e) Date Dec. 22, 1997 PCT Filed Feb. 21, 1995 PCT Pub. No. WO95/22804 PCT Pub. Date Aug. 24, 1995A method and ultra-compact system has been developed for illuminating and detecting the surface topography of an object such as the finger (4) of an individual. The system (8) is capable of producing high-contrast images which can be electronically transmitted in real-time, or stored using electronic or photographic recording devices. Light traveling within a light transmitting substrate (2) is redirected by a slanted-fringed light diffractive grating preferably embodied within a volume hologram (3). The volume hologram (3), either of the reflection or transmission type, is attached to the light transmitting substrate (2). and functions to diffract light striking thereupon and illuminate an object having topographical surface structure. After being spatially and intensity modulated in accordance with topographical details of the illuminated object, the insulated light passes back through the light transmitting substrate (2) and the volume hologram (3), onto an image detection array. for subsequent analysis. Each of the disclosed embodiments has a compact geometry suitable for use in diverse object identification applications.

An intensity modulated radiation therapy (IMRT) system including a radiation beam delivery device positionable in a plurality of spatial orientations, an IMRT control system adapted to modulate at least an intensity of a radiation beam emanating from the radiation beam delivery device depending on at least one of the spatial orientations of the radiation beam delivery device and in accordance with an IMRT intensity map, and a multilayer multileaf collimator placed in a path of the radiation beam emanating from the radiation beam delivery device, the multilayer multileaf collimator including a plurality of layers of radiation blocking leaves, the layers being at different positions along the path of the radiation beam generally traverse to the radiation beam.

A light emissive display having a specular waveguide that propagates short wavelength light and photoluminescent features adjacent to the waveguide that fluoresce, for example, in visible red, green, blue, and mixed colors when selectively coupled with the short wavelength light. The photoluminescent layers emit light primarily and, therefore, efficiently in the direction of an observer only. This light emissive display may be utilized as a planar light source, as patterned information signage, or as a re-configurable information display containing intensity modulated pixels. The light emissive display may be enhanced optically such that only a small portion of ambient light is reflected from the display while preserving the majority of emitted display luminance.

Optical communication apparatuses capable of performing appropriate communication according to a distance to a receiving apparatus, optical communication methods, and an optical communication system are provided. A transmitting apparatus transmits an optical signal corresponding to data. The transmitting apparatus modulates intensity of the optical signal into intensity corresponding to a distance over which the data is to be delivered and outputs this intensity-modulated optical signal. This allows the transmitting apparatus to change the intensity of the optical signal corresponding to the data according to a distance to a receiving apparatus that receives the data, which thus allows the receiving apparatus to surely receive the data.

Semi-integrated external cavity diode laser (ECDL) designs including integrated structures comprising a gain section, phase control section, and optional modulator section. Each integrated structure includes a waveguide that passes through each of the sections. A mirror is defined in the structure to define one end of a laser cavity. A reflective element is disposed generally opposite a rear facet of the gain section, forming an external cavity therebetween. A tunable filter is disposed in the external cavity to effectuate tuning of the laser. During operation, a modulated drive signal is provided to the phase control section. This modulates an optical path length of the laser cavity, which produces an intensity (amplitude) modulation in the laser output. A detector is employed to produce a feedback signal indicative of the intensity modulation that is used for tuning the laser in accordance with a wavelength locking servo loop. Upon passing through the modulator section, an optical signal is modulated with data.

Optical plasmon-wave attenuator and modulator structures for controlling the amount of coupling between an guided optical signal and a surface plasmon wave. Optical power coupled to the plasmon wave mode is dissipated in varying amounts producing an intensity modulation effect on the optical signal. For electrical modulation, an additional dielectric (or polymer) layer with variable refractive index in optical contact with a metal layer supporting at least one plasmon wave mode is used to perturb or vary the propagation constant of plasmon wave. Propagation constant variation results in the power coupling variation between the surface plasmon wave and the optical wave. The refractive index variation of the dielectric (or polymer) layer can be accomplished via an electro-optic traveling-wave, a lump-element, or any other integrated optics modulator configuration situated to affect the layer, thereby permitting data rates into tens of GHz. Because of the extremely small interaction lengths needed, the optical plasmon-wave modulator is a very compact device which can be implemented on the top of a fiber or as an integrated optical planar structure.

Various embodiments of the present invention provide methods and systems for deterministic calculation of radiation doses, delivered to specified volumes within human tissues and organs, and specified areas within other organisms, by external and internal radiation sources. Embodiments of the present invention provide for creating and optimizing computational mesh structures for deterministic radiation transport methods. In general these approaches seek to both improve solution accuracy and computational efficiency. Embodiments of the present invention provide methods for planning radiation treatments using deterministic methods. The methods of the present invention may also be applied for dose calculations, dose verification, and dose reconstruction for many different forms of radiotherapy treatments, including: conventional beam therapies, intensity modulated radiation therapy (“IMRT”), proton, electron and other charged particle beam therapies, targeted radionuclide therapies, brachytherapy, stereotactic radiosurgery (“SRS”), Tomotherapy®; and other radiotherapy delivery modes. The methods may also be applied to radiation-dose calculations based on radiation sources that include linear accelerators, various delivery devices, field shaping components, such as jaws, blocks, flattening filters, and multi-leaf collimators, and to many other radiation-related problems, including radiation shielding, detector design and characterization; thermal or infrared radiation, optical tomography, photon migration, and other problems.

A new optimization method for generating treatment plans for radiation oncology is described and claimed. This new method works for intensity modulated radiation therapy (IMRT), intensity modulated arc therapy (IMAT), and hybrid IMRT.

A probe includes an insertion tube and a plurality of light emitters disposed on the distal end of the insertion tube. The probe further includes at least one intensity modulating element through which light from the plurality of light emitters is passed to project a plurality of fringe sets onto a surface. Each of the plurality of fringe sets intern have a structured-light pattern that is projected when one emitter group of at least one of the plurality of light emitters is emitting. The probe further includes an imager for obtaining at least one image of the surface and a processing unit that is configured to perform phase-shift analysis on the at least one image. A method for projecting a plurality of fringe sets suitable for phase-shift analysis on a surface using a probe is also presented.

A plurality of optical communications systems including a SPW modulator are described. The communications systems include an optical transmitter coupled to an optical fiber communications link which carries a optically modulated information signal to an optical receiver. The laser transmitter includes a laser light source which is optically coupled to a SPW modulator which has been particularly adapted for broadband communications by selecting its transfer characteristic and modulation structure. A broadband signal containing a plurality of information channels, for example CATV channels, is applied to it modulator electrodes. The modulation signal varies the power coupling between the guided laser light source signal and a SPW in the modulator. The result is an intensity modulated optical signal that is output to the optical fiber for transmission to the optical receiver of the system. Alternatively, the communications system includes a high power laser coupled to an optical splitter to divide its output power in two or more optical source outputs. Each optical source output is then used to drive an associated SPW modulator. Each of the modulators receives a broadband signal with which to modulate its optical source. After modulation, the modulated lightwave from a modulator is coupled to a corresponding optical fiber for carriage to an optical receiver. In this manner, several broadband information signals can be communicated over the system using only one laser source. A net benefit from using one higher power laser, rather than several lower power ones, is one of cost, purity and similarity of the several signals. This configuration is enhanced by the lower loss and higher linearity of the SPW modulators. Further, several WDM embodiments including those having serially cascaded SPW modulators are provided. The transfer characteristic of the SPW modulators are tailored to either be more efficient for an analog or a digital modulation signal by adding or subtracting grating effects.

S-band, C-band or X-band microwave powered linear accelerators capable of delivering therapeutic photon and electron beams are mounted to a gantry with extensions to hold multiple accelerators and are combined with a kV CT for 3-D conformal—IMRT and IGRT to treat a patient by SSD or SAD methods and in a full circle. The invention's tertiary collimator system consists of semi-automated reusable custom field shaping with tungsten powder or melted Cerrobend blocks. The beam's intensity modulation is by means of simultaneous but independently operating multiple accelerators. This system's multiple accelerators enable to avoid interrupted subfractionated radiation therapy to each treatment fields. Hence its effective dose rate at the tumor site is high. The improved radiobiology reduces the total radiation dose to treat a tumor, reducing the incidence of developing second primary tumors is also minimized.

The present disclosure relates to microfluidic devices adapted for facilitating cytometry analysis of particles flowing therethrough. In certain embodiments, the microfluidic devices allow light collection from multiple directions. In certain other embodiments, the microfluidic devices use spatial intensity modulation. In certain other embodiments, the microfluidic devices have magnetic field separators. In certain other embodiments, the microfluidic devices have the ability to stack. In certain other embodiments, the microfluidic devices have 3-D hydrodynamic focusing to align sperm cells. In certain other embodiments, the microfluidic devices have acoustic energy couplers. In certain other embodiments, the microfluidic devices have phase variation producing lenses. In certain other embodiments, the microfluidic devices have transmissive and reflective lenses. In certain other embodiments, the microfluidic devices have integrally-formed optics. In certain other embodiments, the microfluidic devices have non-integral geographically selective reagent delivery structures. In certain other embodiments, the microfluidic devices have optical waveguides incorporated into their flow channels. In certain other embodiments, the microfluidic devices have optical waveguides with reflective surfaces incorporated into their flow channels. In certain other embodiments, the microfluidic devices have virus detecting and sorting capabilities. In certain other embodiments, the microfluidic devices display a color change to indicate use or a result.

The invention belongs to the technical field of gas detection and relates to a laser infrared gas analyzer based on TDLAS-WMS (tunable diode laser absorption spectroscopy-wavelength modulation spectroscopy) for detecting hydrogen chloride, methane, carbon monoxide, water vapor and other gases. The laser infrared gas analyzer comprises a laser, a laser driving circuit, a temperature control circuit, an optical system with an optical cavity, a main detector, a reference detector, an intensity modulation and canceling circuit, a phase-locking and amplification circuit and a data acquisition and display circuit, wherein the laser driving circuit and the temperature control circuit are used for controlling the laser to emit light, the two ends of the optical system are respectively connected with the laser and the detector, the intensity modulation and canceling circuit is used for canceling the influence of intensity modulation in the system, the phase-locking and amplification circuit is used for extracting harmonic signals, and the data acquisition and display circuit is used for displaying the concentration of the gas to be detected. Compared with other detection instruments, the laser infrared gas analyzer has the advantages that division operation is introduced into the intensity modulation and canceling circuit, and the laser infrared gas analyzer is combined with a space double-optical path differential detection method, so that the influence of the intensity modulation can be fundamentally canceled.

A device contains at least one wavelength-tunable multilayer interference reflector controlled by an applied voltage and at least one cavity. The stopband edge wavelength of the wavelength-tunable multilayer interference reflector is preferably electrooptically tuned using the quantum confined Stark effect in the vicinity of the cavity mode (or a composite cavity mode), resulting in a modulated transmittance of the multilayer interference reflector. A light-emitting medium is preferably introduced in the cavity or in one of the cavities permitting the optoelectronic device to work as an intensity-modulated light-emitting diode or diode laser by applying an injection current. The device preferably contains at least three electric contacts to apply forward or reverse bias and may operate as a vertical cavity surface emitting light-emitter or modulator or as an edge-emitting light emitter or modulator. Using a multilayer interference reflector containing tunable section allows also obtaining a wavelength-tunable laser or a wavelength-tunable resonant cavity photodetector in the case where the optical field profile in the active cavity or cavities is affected by the stopband wavelength shift. Adding additional modulator sections enables applications in semiconductor optical amplifiers, frequency converters or lock-in optical amplifiers.

The present invention relates to a device and method for monitoring and verification of the quality of a radiation treatment beam in conformal radiation therapy, and in particular for IMPT (Intensity Modulated Particle Therapy) applications. The device comprises a 2D electronic detector measuring 2D responses to the delivered treatment beam. These 2D responses are compared with predicted 2D responses and differences in responses are signalled. Based on the measured 2D responses the effectively delivered 3D dose distribution in the target can be reconstructed.

A laser distance measuring device (1) includes a laser diode (4) for emitting a high frequency intensity modulated measurement light beam (3) and connected with a signal generating unit (SGU) that generates a high frequency measurement signal (9) for high frequency signal transfer, at least one receiver photodetector (8a) for receiving a measurement light beam (3) reflected from a measurement object (5) and connected to a high frequency demodulator (13) for generating a low frequency phase delay signal (S₁) containing phase information of the reflected intensity modulated measurement light beam (3), and a microcontroller (μC) for calculating a distance (D) from the phase delay signal (S₁) and connected to the high frequency demodulator (13), with the microcontroller (μC) being connected to a control photodetector (8c) arranged in the measurement light beam (3) for low frequency transfer for determining an interference modulation component.