12793results about "Scattering properties measurements" patented technology

In a method of determining the focus of a lithographic apparatus used in a lithographic process on a substrate, the lithographic process is used to form a structure on the substrate, the structure having at least one feature which has an asymmetry in the printed profile which varies as a function of the focus of the lithographic apparatus on the substrate. A first image of the periodic structure is formed and detected while illuminating the structure with a first beam of radiation. The first image is formed using a first part of non-zero order diffracted radiation. A second image of the periodic structure is foamed and detected while illuminating the structure with a second beam of radiation. The second image is formed using a second part of the non-zero order diffracted radiation which is symmetrically opposite to the first part in a diffraction spectrum. The ratio of the intensities of the measured first and second portions of the spectra is determined and used to determine the asymmetry in the profile of the periodic structure and / or to provide an indication of the focus on the substrate. In the same instrument, an intensity variation across the detected portion is determined as a measure of process-induced variation across the structure. A region of the structure with unwanted process variation can be identified and excluded from a measurement of the structure.

An optical-based sensor for detecting the presence or amount of an analyte using both indicator and reference channels. The sensor has a sensor body with a source of radiation embedded therein. Radiation emitted by the source interacts with indicator membrane indicator molecules proximate the surface of the body. At least one optical characteristic of these indicator molecules varies with analyte concentration. For example, the level of fluorescence of fluorescent indicator molecules or the amount of light absorbed by light-absorbing indicator molecules can vary as a function of analyte concentration. In addition, radiation emitted by the source also interacts with reference membrane indicator molecules proximate the surface of the body. Radiation (e.g., light) emitted or reflected by these indicator molecules enters and is internally reflected in the sensor body. Photosensitive elements within the sensor body generate both indicator channel and reference channel signals to provide an accurate indication of the concentration of the analyte. Preferred embodiments are totally self-contained and are sized and shaped for use in vivo in a human being. Such embodiments preferably include a power source, e.g. an inductor, which powers the source of radiation using external means, as well as a transmitter, e.g. an inductor, to transmit to external pickup means the signal representing the level of analyte.

The Laser Induced Fluorescence Attenuation Spectroscopy (LIFAS) method and apparatus preferably include a source adapted to emit radiation that is directed at a sample volume in a sample to produce return light from the sample, such return light including modulated return light resulting from modulation by the sample, a first sensor, displaced by a first distance from the sample volume for monitoring the return light and generating a first signal indicative of the intensity of return light, a second sensor, displaced by a second distance from the sample volume, for monitoring the return light and generating a second signal indicative of the intensity of return light, and a processor associated with the first sensor and the second sensor and adapted to process the first and second signals so as to determine the modulation of the sample. The methods and devices of the inventions are particularly well-suited for determining the wavelength-dependent attenuation of a sample and using the attenuation to restore the intrinsic laser induced fluorescence of the sample. In turn, the attenuation and intrinsic laser induced fluorescence can be used to determined a characteristic of interest, such as the ischemic or hypoxic condition of biological tissue.

Methods are disclosed for measuring target structures formed by a lithographic process on a substrate. A grating structure within the target is smaller than an illumination spot and field of view of a measurement optical system. The optical system has a first branch leading to a pupil plane imaging sensor and a second branch leading to a substrate plane imaging sensor. A spatial light modulator is arranged in an intermediate pupil plane of the second branch of the optical system. The SLM imparts a programmable pattern of attenuation that may be used to correct for asymmetries between the first and second modes of illumination or imaging. By use of specific target designs and machine-learning processes, the attenuation patterns may also be programmed to act as filter functions, enhancing sensitivity to specific parameters of interest, such as focus.

Apparatus, method, logic arrangement and storage medium are provided for increasing the sensitivity in the detection of optical coherence tomography and low coherence interferometry (“LCI”) signals by detecting a parallel set of spectral bands, each band being a unique combination of optical frequencies. The LCI broad bandwidth source can be split into N spectral bands. The N spectral bands can be individually detected and processed to provide an increase in the signal-to-noise ratio by a factor of N. Each spectral band may be detected by a separate photo detector and amplified. For each spectral band, the signal can be band p3 filtered around the signal band by analog electronics and digitized, or, alternatively, the signal may be digitized and band pass filtered in software. As a consequence, the shot noise contribution to the signal is likely reduced by a factor equal to the number of spectral bands, while the signal amplitude can remain the same. The reduction of the shot noise increases the dynamic range and sensitivity of the system.

A control system for automatically detecting moisture on the windshield of a vehicle. The automatic moisture detecting system includes an optical system for imaging a portion of the windshield on to an image array sensor, such as a CMOS active pixel sensor. The voltages of each of the pixels which represents the illumination level is converted to a corresponding gray scale value by an analog digital converter. The gray scale values corresponding to the image are stored in memory. The spatial frequency composition of the gray scale values are analyzed to determine the amount of rain present. In order to provide a control signal to control the operation of the windshield wipers of the vehicle as a function of the amount of moisture present. The system is also adapted to detect the level of fog both on the interior of the windshield as well as the exterior of the windshield. By providing a system for automatically detecting the presence of fog on the interior and exterior of the windshield, serious performance limitations of known automatic rain sensors are eliminated.

An apparatus for optically analyzing a substrate. The apparatus includes: (a) a light source for directing light onto the substrate; (b) optics for creating an optical path from light reflected from the substrate; and (c) a multiple wavelength imaging optical subsystem positioned in the optical path. The multiple wavelength imaging optical subsystem includes: (i) one or more filters which are capable of one or both of: (1) being alternatively or sequentially interposed in the optical path to extract one or more of wavelengths or wavelength bands of interest; or (2) having their wavelength selectivity adjusted to extract one or more wavelengths or wavelength bands of interest; and (ii) one or more imaging devices positioned to image the extracted wavelengths or wavelength bands of interest from the one or more filters; (d) an imaging device positioned in the optical path. Also a method is included, making use of the apparatus for analysis of a substrate.

An apparatus and method to determine a property of a substrate by measuring, in the pupil plane of a high numerical aperture lens, an angle-resolved spectrum as a result of radiation being reflected off the substrate. The property may be angle and wavelength dependent. The radiation that is reflected off the substrate is radially polarized.

Systems, and components thereof, for analyzing samples. These systems include apparatus and methods for generating, transmitting, detecting, and / or analyzing light, including without limitation high-throughput optical screening devices for analyzing samples at one or more assay sites. These systems also include apparatus and methods for supporting samples for analysis, including without limitation multiwell sample holders such as microplates.

The invention provides a design process that is used in the determination of the pattern of detector and illumination optical fibers at the sampling area of a subject. Information about the system, specifically a monochromator (e.g. to determine the optimal number of fibers at an output slit) and the bundle termination at a detector optics stack (e.g. to determine the optimal number of fibers at the bundle termination), is of critical importance to this design. It is those numbers that determine the ratio and number of illumination to detection fibers, significantly limiting and constraining the solution space. Additional information about the estimated signal and noise in the skin is necessary to maximize the signal-to-noise ratio in the wavelength range of interest. Constraining the fibers to a hexagonal perimeter and prescribing a hex-packed pattern, such that alternating columns contain illumination and detection fibers, yields optimal results. In the preferred embodiment of the invention, two detectors share the totality of the detection fibers at the sampling interface. A third group of detection fibers is used for classification purposes.

Methods and compositions are provided for detecting biomolecular interactions. The use of labels is not required and the methods can be performed in a high-throughput manner. The invention also provides optical devices useful as narrow band filters.

A bodily fluid sampling device includes a piercing device and a sensor enclosed in a housing. A cassette, which contains test media, is positioned proximal to the sensor so that the sensor is able to analyze a bodily fluid sample collected on the test media. The cassette includes a supply portion from which unused test media is supplied and a storage portion in which contaminated test media is stored after exposure to the bodily fluid. The cassette is adapted to collect a series of bodily fluid samples without requiring disposal of the test media.

A patient monitor system implemented by a service provider for users via recording a patients analytes measurements by an attenuated total reflection (ATR) infrared total spectroscopy method. The system comprises an input module that provides a non-invasive method in measuring analytes in a patient, such as a measurement of the glucose level and other blood analytes. The measurement is shared among a plurality of output devices such as computers, personal digital assistants (PDAs), cellular phones, and pagers that are stationed or held by various users such as doctors, patients, researchers, pharmacies, labs, and health insurers. In addition behavioral attributes are recorded and correlated with the analytes measurements to generate a profile. The profile is selectively sent to output devices based on the user profile corresponding to the output device. Also, access to the profile is monitored by a security module that encrypts the profile to prevent access by un-authorized users.

An apparatus includes a first section operable to detect polarization-sensitive radiation emitted by an object, and a second section operable to determine a Jones matrix based on information obtained by the first section from the polarization-sensitive radiation. The second section thereafter transforms the Jones matrix into a Mueller matrix, the Mueller matrix being representative of properties of the object.

Method and apparatus for detecting biomolecular interactions. The use of labels is not required and the methods may be performed in a high-throughput manner. An instrument system for detecting a biochemical interaction on a biosensor. The system includes an array of detection locations comprises a light source for generating collimated white light. A beam splitter directs the collimated white light towards a surface of a sensor corresponding to the detector locations. A detection system includes an imaging spectrometer receiving the reflected light and generating an image of the reflected light.

An apparatus and source arrangement for filtering an electromagnetic radiation can be provided which may include at least one spectral separating arrangement configured to physically separate one or more components of the electromagnetic radiation based on a frequency of the electromagnetic radiation. The apparatus and source arrangement may also have at least one continuously rotating optical arrangement which is configured to receive at least one signal that is associated with the one or more components. Further, the apparatus and source arrangement can include at least one beam selecting arrangement configured to receive the signal.

An apparatus and method for non-invasive measurement of glucose in human tissue by quantitative infrared spectroscopy to clinically relevant levels of precision and accuracy. The system includes six subsystems optimized to contend with the complexities of the tissue spectrum, high signal-to-noise ratio and photometric accuracy requirements, tissue sampling errors, calibration maintenance problems, and calibration transfer problems. The six subsystems include an illumination subsystem, a tissue sampling subsystem, a calibration maintenance subsystem, an FTIR spectrometer subsystem, a data acquisition subsystem, and a computing subsystem.

Filtering of optical fibers and other related devices. High-energy methods for depositing thin films directly onto the ends of optical fibers can be used to produce high-quality, high-performance filters in quantity at a reasonable cost. These high-quality filters provide the high performance needed for many demanding applications and often eliminate the need for filters applied to wafers or expanded-beam filtering techniques. Having high-quality filters applied directly to optical fiber and faces permits production of high-performance, micro-sized devices that incorporate optical filters. Devices in which these filters may be used include spectroscopic applications including those using fiber optic probes, wavelength division multiplexing, telecommunications, general fiber optic sensor usage, photonic computing, photonic amplifiers, pump blocking and a variety of laser devices.

An optical coherence tomography (OCT) system including an interferometer provides illuminating light along a first optical path to a sample and an optical delay line and collects light from the sample along a second optical path remitted at several scattering angles to a detector. In one embodiment, illuminating light is directed along a number of incident light paths through a focusing lens to a sample. The light paths and focusing lens are related to the sample and to both the incident light source and the detector. In another embodiment, a focusing system directs light to a location in the sample. A transmission grating or acousto-optic modulator directs light from the sample at an angle representative of the wavelength of the incident light on the transmission grating or acousto-optic modulator.