A method for determining the growth stage of a plant is disclosed. The method comprises illuminating the plant with illumination light. The illumination light causes response light from the plant. The method further comprises detecting the response light from the plant, and, based on the detected response light, determining the growth stage of the plant. In this method, (i) illuminating the plant comprises illuminating with at least partially polarized illumination light, and/or (ii) detecting the response light comprises polarization filtering the response light.

The present disclosure generally relates to machine vision systems, illumination sources for use in machine vision systems, and components for use in the illumination sources. More specifically, the present disclosure relates to machine vision systems incorporating multi-function illumination sources, multi-function illumination sources, and components for use in multi-function illumination sources.

An example system for detecting pipe defects is provided. The system includes a transmitter, a receiver and a processing device. The transmitter is oriented to transmit Terahertz (THz) waveform pulses towards at least one of an outer surface of a pipe or an inner surface of the pipe. The receiver is oriented to receive reflected Terahertz (THz) waveform pulses from at least one of the outer surface of the pipe or the inner surface of the pipe. The processing device configured is to receive as input the Terahertz (THz) waveform pulses transmitted from the transmitter and the reflected Terahertz (THz) waveform pulses received by the receiver and, based on the received input, determine if a defect in the pipe exists.

A measurement system for use in measuring parameters of a patterned sample, the system including a broadband light source, an optical system configured as an interferometric system, a detection unit, and a control unit, where the interferometric system defines illumination and detection channels having a sample arm and a reference arm having a reference reflector, and is configured for inducing an optical path difference between the sample and reference arms, the detection unit for detecting a combined light beam formed by a light beam reflected from the reflector and a light beam propagating from a sample's support, and generating measured data indicative of spectral interference pattern formed by spectral interference signatures, and the control unit for receiving the measured data and applying a model-based processing to the spectral interference pattern for determining one or more parameters of the pattern in the sample.

An inspection system including an illumination subsystem and an image sensing subsystem, the illumination subsystem providing a plurality of illumination modalities, the system simultaneously illuminating at least two areas of an object with different ones of the plurality of illumination modalities, images of which are acquired by a single sensor forming part of the image sensing subsystem.

Additive manufacturing, such as laser sintering or melting of additive layers, can produce parts rapidly at small volume and in a factory setting. To ensure the additive manufactured parts are of high quality, a real-time non-destructive evaluation (NDE) technique is required to detect defects while they are being manufactured. The present invention describes an in-situ (real-time) inspection unit that can be added to an existing additive manufacturing (AM) tool, such as an FDM (fused deposition modeling) machine, or a direct metal laser sintering (DMLS) machine, providing real-time information about the part quality, and detecting flaws as they occur. The information provided by this unit is used to a) qualify the part as it is being made, and b) to provide feedback to the AM tool for correction, or to stop the process if the part will not meet the quality, thus saving time, energy and reduce material loss.

A surface defect measuring apparatus and method by microscopic scattering polarization imaging is provided. The apparatus mainly comprises a laser, a first converging lens, a rotary diffuser, a second converging lens, a diaphragm, a third converging lens, a pinhole, a fourth converging lens, a polarizer, a half-wave plate, a polarizing beam splitter, an X-Y translation stage, a sample, a microscope lens, a quarter-wave plate, a micro-polarizer array, a camera and a computer. The micro-polarizer array is adopted to realize real-time microscopic scattering polarization imaging of the surface defects; a polarization-degree image is calculated to improve the sensitivity for detecting the surface defects of the ultra-smooth element, and the effective detection of the surface defects of a high-reflective coating element is also realized, and the requirement for rapid detection of the surface defects of a meter-scale large-aperture ultra-smooth element can be met.

A system for optical imaging of defects on unpatterned wafers that includes an illumination module, relay optics, a segmented polarizer, and a detector. The illumination module is configured to produce a polarized light beam incident on a selectable area of an unpatterned wafer. The relay optics is configured to collect and guide, radiation scattered off the area, onto the polarizer. The detector is configured to sense scattered radiation passed through the polarizer. The polarizer includes at least four polarizer segments, such that (i) boundary lines, separating the polarizer segments, are curved outwards relative to a plane, perpendicular to the segmented polarizer, unless the boundary line is on the perpendicular plane, and (ii) when the area comprises a typical defect, a signal-to-noise ratio of scattered radiation, passed through the polarizer segments, is increased as compared to when utilizing a linear polarizer.

According to one embodiment, an optical imaging apparatus includes: an image-forming optical portion, a wavelength selection portion, and an imaging portion. The image-forming optical portion forms an image of an object by means of light beams that include a first wavelength and a second wavelength different from the first wavelength. The first wavelength selection portion has wavelength selection regions. The wavelength selection regions are an anisotropic wavelength selection opening having a different distribution of the wavelength selection regions depending on a direction along a first axis and a direction along a second axis. The imaging portion is configured to simultaneously acquire an image of the first light beam and the second light beam.

A test structure for use in metrology measurements of a sample pattern formed by periodicity of unit cells, each formed of pattern features arranged in a spaced-apart relationship along a pattern axis, the test structure having a test pattern, which is formed by a main pattern which includes main pattern features of one or more of the unit cells and has a symmetry plane, and a predetermined auxiliary pattern including at least two spaced apart auxiliary features located within at least some of those features of the main pattern, parameters of which are to be controlled during metrology measurements.