An inspection system may include an illumination source to generate an illumination beam, illumination optics to direct the illumination beam to a sample. The system may further include a first collection channel to collect light from the sample within a first range of solid angles and at a first selected polarization. The system may further include a second collection channel to collect light from the sample within a second angular range, the second range of solid angles and at a second selected polarization. The system may further include a controller to receive two or more scattering signals. The scattering signals may include signals from the first and second collection channels having selected polarizations. The controller may further determine depths of defects in the sample based on comparing the two or more scattering signals to training data including data from a training sample having known defects at known depths.

Methods and systems for performing high throughput spectroscopic measurements of semiconductor structures at mid-infrared wavelengths are presented herein. A Fourier Transform Infrared (FTIR) spectrometer includes one or more measurement channels spanning a wavelength range between 2.5 micrometers and 12 micrometers. The FTIR spectrometer measures a target at multiple different angles of incidence, azimuth angles, different wavelength ranges, different polarization states, or any combination thereof. In some embodiments, illumination light is provided by a laser sustained plasma (LSP) light source to achieve high brightness and small illumination spot size. In some embodiments, FTIR measurements are performed off-axis from the direction normal to the surface of the wafer. In some embodiments, a Stirling cooler extracts heat from the detector of an FTIR spectrometer. In another aspect, measurements performed by one or more spectrometer measurement channels are combined with measurements performed by a mid-infrared FTIR spectrometer channel to characterize high aspect ratio structures.

Disclosed is a device for measuring radiation doses absorbed by a gel dosimeter, including in particular a polarizer for a light beam according to at least two distinct polarization angles, the polarizer being positioned between a light source and an optical detector, a unit for measuring the value of the intensity of the light beam, which intensity is measured by the optical detector, and a unit for calculating the value of a ratio of intensities of the light beam, which intensities are measured by the optical detector, for two distinct polarization angles of the light beam that is selected by the polarizer.

A method of operating a detection system includes switching the system from a normal mode for sensing smoke to a high sensitivity mode for sensing airborne particles, such that in the high sensitivity mode the detection system is configured to discriminate between particles of diameters less than 2.5 micrometers and 10 micrometers. Transmitting light from one or more light sources of the detection system into a monitored space, and detecting scattered light at one or more light sensing devices of the detection system. The detection of scattered light is indicative of one or more indoor air quality conditions in the monitored space.

The integrated smoke detection device comprises a carrier (1), a light source (2) arranged on or above the carrier, a light receiver (3) arranged on or above the carrier at a distance from the light source, and a polarizing member (7) arranged on or above the carrier, the light source emitting radiation (a, b) into the polarizing member. The polarizing member is configured to have a boundary surface (11) that linearly polarizes a reflected portion (d) of the radiation emitted by the light source, and an exit surface (12) that allows the reflected portion (d) to exit the polarizing member.

A polarization property image measurement device includes: a first radiation unit that radiates light beams in different polarization conditions onto a target object after subjecting the light beams to intensity modulation at frequencies different from one another; a light receiving unit including first photoelectric conversion units that photoelectrically convert the light beams having been radiated from the first radiation unit and scattered at the target object in correspondence to each of the different polarization conditions, and second photoelectric conversion units that photoelectrically convert visible light from the target object; and a processor that detects signals individually output from the first photoelectric conversion units at the different frequencies and differentiates each signal from other signals so as to determine an origin of the signal as one of the light beams; and creates an image of the target object based upon signals individually output from the second photoelectric conversion units.

A micro object detection apparatus (11) includes an optical system (50). The first optical system (50) includes a first reflection region (101), a second reflection region (102), and a light reception element (6). The first reflection region (101) has an ellipsoidal shape, and reflects scattered light scattered when irradiation light hits a particle (R) to direct the scattered light to the light reception element (6), by utilizing two focal point positions of the ellipsoidal shape. The second reflection region (102) reflects scattered light coming from the particle (R) to direct the scattered light to the first reflection region (101), so that the scattered light is directed to the light reception element (6) by utilizing the ellipsoidal shape of the first reflection region (101). The light flux diameter of the scattered light reflected by the second reflection region (102) is larger than the particle (R), at the position of the particle (R) at which the scattered light is generated.

Apparatus and associated methods relate to reliably determining both size of large water droplets and density of small water droplets in a multi-modal cloud atmosphere. A pulsed beam of light is projected into the cloud atmosphere and a receiver receives a reflected portion of the projected pulsed beam backscattered by the cloud atmosphere. The received reflected portion is split into first and second parts. First and second parts are directed to first and second detectors, each having a different gain. A ratio of the gains of the first and second detector is greater than 3:1, thereby providing a low-gain detector for producing unsaturated signals indicative of scintillation spike reflection by large water particles and a simultaneous high-gain detector for producing signals indicative of range-resolved reflections by numerous small water particles.

Methods of characterizing an optical retardance or a stress-related property of a glass-bases sample include directing a light beam into the glass-based sample while varying the polarization of the light beam to generate scattered light for each polarization are provided. The scattered light for each polarization is captured with an image sensor, which has an exposure time and a frame rate. The scattered light has an intensity distribution at the image sensor. The sample is moved so that the image sensor averages two or more different intensity distributions per frame to form an averaged intensity distribution for each polarization. The averaged intensity distributions for multiple frames are then used to characterize the optical retardance. The optical retardance can turn be used to determine stress-related properties of the glass-based sample. Moving the substrate reduces measurement noise scattered light having no optical retardance information.

A polarization property image measurement device includes: a first radiation unit that radiates light beams in different polarization conditions onto a target object after subjecting the light beams to intensity modulation at frequencies different from one another; a light receiving unit including first photoelectric conversion units that photoelectrically convert the light beams having been radiated from the first radiation unit and scattered at the target object in correspondence to each of the different polarization conditions, and second photoelectric conversion units that photoelectrically convert visible light from the target object; and a processor that detects signals individually output from the first photoelectric conversion units at the different frequencies and differentiates each signal from other signals so as to determine an origin of the signal as one of the light beams; and creates an image of the target object based upon signals individually output from the second photoelectric conversion units.