An optical inspector includes a time varying beam reflector, a radiating source that irradiates the time varying beam reflector, a telecentric scan lens configured to direct the radiation reflected by the time varying beam reflector onto a first surface of a transparent sample, a first detector that receives at least a portion of top surface specular reflection, a second detector that receives at least a portion of the bottom surface specular reflection. A turning mirror may also be included. The turning mirror is a switchable mirror that can be adjusted to a first position where the turning mirror reflects the top and bottom surface specular reflection, and can be adjusted to a second position where the turning mirror does not reflect the top or the bottom surface specular reflection. A first and second polarizing element may also be included to detect additional types of defects on either surface.

Raman instrumentation for detecting for the presence of a molecular species in a including: a source of radiation for pumping the sample; apparatus for controlling the frequency and pulse width of radiation from the pumping source; a Raman spectrometer including a detector and means for collecting scattered photons from the sample; a radiation source for probing the sample; means for directing radiation from the probing source to the sample; and means to interface the spectrometer with the source of radiation for pumping. The radiation source for probing is, preferably, a monochromatic light source emitting radiation in at least one of the group including UV, visible, and near infrared radiation and, preferably, in the range of 220-1080 nm. The photons collected from the sample include elastically and inelastically scattered photons, and the spectrometer further including means for rejecting the elastically scattered photons. The pumping source is a microwave source.

A method for detecting defects includes directing a scanning beam to a location on a surface of a transparent sample, measuring top and bottom surface specular reflection intensity, and storing coordinate values of the first location and the top and bottom surface specular reflection intensity in a memory. The method may further include comparing the top surface specular reflection intensity measured at each location with a first threshold value, comparing the bottom surface specular reflection intensity measured at each location with a second threshold value, and determining if a defect is present at each location and on which surface the defect is present. The method may further include comparing the top surface specular reflection intensity measured at each location with a first intensity range, comparing the bottom surface specular reflection intensity measured at each location with a second intensity range, and determining on which surface the defect is present.

A novel detection system and method is presented, where a two-bead receptor method is used for capturing pathogens, with one type of bead being magnetic and having a size of 3 microns or smaller, and the other type being polymeric and having a size of 3 microns or larger. The first type is used to concentrate a pathogen; the latter is used to create a detectable signal. Fast sensitive detection is achieved by collecting the optical signal created by the distortion of a homeotropically aligned chromonic azo dye in the presence of captured pathogens.

A pulse multiplier includes a polarizing beam splitter, a wave plate, and a set of mirrors. The polarizing beam splitter receives an input laser pulse. The wave plate receives light from the polarized beam splitter and generates a first set of pulses and a second set of pulses. The first set of pulses has a different polarization than the second set of pulses. The polarizing beam splitter, the wave plate, and the set of mirrors create a ring cavity. The polarizing beam splitter transmits the first set of pulses as an output of the pulse multiplier and reflects the second set of pulses into the ring cavity. This pulse multiplier can inexpensively reduce the peak power per pulse while increasing the number of pulses per second with minimal total power loss.

A system for providing active real-time characterization of an article under test is disclosed. An infrared light source, a first visible light source and a second visible light source each outputs and directs a beam of coherent light at a particular area on the article under test. A visible light camera and a visible light second harmonic generation camera, an infrared camera and an infrared second harmonic generation camera, a sum frequency camera and a third order camera are each configured to receive a respective predetermined return beam of light from the particular area on the article under test. A processor receives signals from the cameras and calculates in real time respective spectroscopic signals and compares each calculated signal with each other calculated signal and with a predetermined baseline signal to ensure that the article under test conforms to an expected value.

A spectroscopic ellipsometry system and method for thin film measurement with high spatial resolution. The system includes a rotating compensator so that spectroscopic ellipsometric and imaging ellipsometric data are collected simultaneously with the same measurement beam. Collecting both ellipsometric data sets simultaneously increases the information content for analysis and affords a substantial increase in measurement performance.

Embodiments of the subject invention relate to a method and apparatus for performing measurements using multiphoton or second harmonic generation (SHG) scattered radiation from a sample including a turbid (scattering) medium includes providing a beam of laser pulses from a laser source having high pulse energies and a repetition rate; splitting the beam of laser pulses into two or more partial beams and focussing and overlaying the partial beams on a sample including the turbid medium; and detecting multiphoton and second harmonic radiation scattered from the sample.

A birefringence measurement device includes a light flux generator for generating light flux, a light flux irradiator for irradiating a measurement target with the light flux in a predetermined polarization state, an imaging optical system for forming an image from light flux transmitted through the measurement target, a polarization/diffraction grating positioned within the imaging optical system, an image pickup for generating a light-dark signal related to brightness of the image, and an output for outputting information regarding a phase difference for the light flux. The phase difference resulting from the transmission through the measurement target is determined on the basis of the light-dark signal. The image pickup generates the light-dark signal for the image based on at least one beam of diffracted light from among a plurality of beams of diffracted light produced by the grating. A two-dimensional distribution of birefringence is obtained in real time without a rotating mechanism.

An apparatus and method for determining the concentration of chiral molecules in a fluid includes a first polarizer configure to polarize light in substantially a first plane to provide initially polarized light. A second polarizer is capable of polarizing the initially polarized light in a plurality of planes, at least one of the plurality of planes being different from the first plane, to provide subsequently polarized light. One or more receivers are included for measuring an intensity of the subsequently polarized light in one or more of the plurality of planes.