Abstract:
An optical characteristic measuring apparatus includes: a light source section which sweeps wavelengths of a first input light and a second input light respectively, frequencies of the first and second input lights being different from each other and polarized states of the first and second input lights being perpendicular to each other, and outputs the first and second input light; an interference section which inputs one branched light of the first and second input lights to a measuring object, makes output light from the measuring object interfere with other branched light of the first and second input lights, and outputs a plurality of interference lights; a plurality of light receiving sections which are respectively provided for the interference lights, receives the interference lights respectively, and outputs signals in accordance with optical powers of the interference lights respectively; and a low-pass filter for filtering the outputted signals.
Abstract:
Determining relationships between one laser beam and an object onto which such beam is directed including: directing such beam onto the object; collecting radiation from the beam that is reflected back; spectrally discriminating the collected, reflected radiation from other collected radiation; generating an image of the collected beam radiation; and analyzing this image to determine the value of at least one parameter selected from: the diameter of the beam on the object; the position of the beam on the object; and beam quality on the object. The determined value(s) may be used to adjust parameter(s) of the beam. Additional steps include directing a second beam onto the object and collecting, spectrally discriminating, generating an image and analyzing it to determine the value of at least one parameter related to the second beam. The forgoing may also include utilizing the determined second value to adjust parameter(s) of the second beam.
Abstract:
An optical characteristic measuring apparatus includes: a light source section which sweeps wavelengths of a first input light and a second input light respectively, frequencies of the first and second input lights being different from each other and polarized states of the first and second input lights being perpendicular to each other, and outputs the first and second input light; an interference section which inputs one branched light of the first and second input lights to a measuring object, makes output light from the measuring object interfere with other branched light of the first and second input lights, and outputs a plurality of interference lights; a plurality of light receiving sections which are respectively provided for the interference lights, receives the interference lights respectively, and outputs signals in accordance with optical powers of the interference lights respectively; and a low-pass filter for filtering the outputted signals.
Abstract:
A sensor containing a beam emitter that emits a first beam having laser, a beam-splitting interferometer and an array detector, wherein the first beam is to strike a sample that produces a second beam comprising a Raman signal, the beam-splitting interferometer is to create a phase delay in the second beam, and the array detector comprises a plurality of detectors is disclosed. The sensor could be used for spectroscopic detection of a sample by generating a first beam comprising laser, striking the first beam to a sample to produce a second beam comprising a Raman signal, creating a phase delay in the second beam and detecting the Raman signal of the second beam. The uses of the sensor include detection of biological and chemical warfare agents, narcotics, among others for homeland security.
Abstract:
The invention features a method including: (i) providing spectrally resolved information about light coming from different spatial locations in a sample comprising deep tissue in response to an illumination of the sample, wherein the light includes contributions from different components in the sample; (ii) decomposing the spectrally resolved information for each of at least some of the different spatial locations into contributions from spectral estimates associated with at least some of the components in the sample; and (iii) constructing a deep tissue image of the sample based on the decomposition to preferentially show a selected one of the components.
Abstract:
A method for demodulating signals from a dispersive, white light interferometer includes generating test interferometry spectra from an interferometer forming part of a sensor for various values of interferometer sensor optical path length. The various test spectra are correlated to a measured spectrum from the sensor to generate a correlation function. The sensor optical path length resulting in the correlation function value reaching a maximum is selected as the optical path length
Abstract:
A microscope apparatus includes a microscope, and a time-resolved spectroscopy unit, a first light-guiding unit for guiding light from the speetroscopy unit into the microscope, a second light-guiding unit for guiding the light from the microscope into the spectroscopy unit. The microscope includes an illuminating optical system and an observing optical system. The time-resolved spectroscopy unit includes an ultrashort optical pulse source, a beam splitter for splitting the ultrashort optical pulse into a reference beam and another beam, an optical system for generating a pump beam and a probe beam from the beam other than the reference beam, and an imaging device for time-resolved spectroscopy for capturing an interference pattern formed by the light guided by the second light-guiding unit and the reference beam. A two-dimensional lightwave conversion optical system is interposed between the second light-guiding unit and the imaging device.
Abstract:
A sensor having a beam emitter that emits a first beam comprising laser, a spectrometer and an array detector, wherein the first beam is to strike a fluid that produces a second beam comprising a Raman signal and the array detector comprises a plurality of detectors, further wherein the sensor is capable of detecting the presence or absence of the fluid in a given space without contacting the fluid is disclosed. The sensor could be used for spectroscopic detection of a fluid by generating a first beam comprising laser, striking the first beam to the fluid to produce a second beam having a Raman signal, passing the second beam through a spectrometer and analyzing the Raman signal of the second beam to the detect the presence or absence of the fluid. The uses of the sensor include detecting of fuel in a pipeline during midair refueling.
Abstract:
A dynamic light scattering measurement apparatus using a phase modulation type interference method includes an optical coupler for dividing light from a low coherent light source, a converging lens for irradiating one of the divided lights to a sample 9, phase modulators for modulating the phase of the other divided lights, a spectrum measurement means for measuring a spectrum of the interference light of the phase-modulated reference light and the scattered light outgoing from the sample, and an analyzing means for measuring the dynamic light scattering of particles of the sample based on the first order spectrum corresponding to the basic frequency of the phase-modulating signal or a higher order spectrum corresponding to a frequency equal to two, three or the like times the basic frequency appearing in the interference light spectrum measured by the spectrum measurement means. An amount s/L obtained by normalizing the light path length s within the sample by the mean free path L of the particles is set to be not more than 3. Dynamic properties of a high concentration medium can be measured with high precision based on the scattered light from such medium.
Abstract:
A method and apparatus for improved defocus detection on wafers. The use of hyperspectral imaging provides increased sensitivity for local defocus defects, and the use of Fourier Space analysis provides increased sensitivity for extended defocus defects. A combination of the two provides improved overall sensitivity to local and extended defocus defects.