G01M11/005

Global dynamic detection method and system for protective film of photomask

A global dynamic detection method for a protective film of a photomask includes: causing the protective film to undergo broadband oscillation; applying a broadband signal to the protective film undergoing multi-frequency oscillation; transforming an optical time-domain signal reflecting off the protective film to obtain a frequency spectrum with multiple resonance frequencies; and detecting the protective film with the frequency spectrum comprehensively to ensure the quality of the protective film. A global dynamic detection system for use with the global dynamic detection method is further provided.

Methods and apparatus for rating eyeglass protection from infrared exposure

Conventionally, eyewear is rated in terms of its absorption coefficient (sometimes called the optical density (OD)) or the protection that it provides from ultraviolet (UV) radiation, which can damage the eye at high enough power levels. Infrared (IR) radiation can also damage the eye, but IR damage tends to occur at a much slower rate than UV-induced damage. Rating eyewear in terms of protection from IR radiation and/or in terms of a maximum safe exposure duration (SED) to IR radiation improves consumers' ability to protect themselves from IR radiation. In addition, eyewear rated for more IR protection or longer SED may still provide excellent vision thanks to coatings that reflect or absorb IR light and transmit visible light.

METHOD AND APPARATUS FOR INSPECTION OF SPHERICAL SURFACES
20200378755 · 2020-12-03 ·

Disclosed are a method and an apparatus for inspection of workpieces and products having curved and, in particular, spherical surfaces. The method is based on scanning inspected objects with a narrow probing beam of electromagnetic radiation and concurrently measuring the radiation scattered on the surface. The method and apparatus improve the detectability of features and imperfections on inspected surfaces by providing invariable parameters and conditions of scanning, robust mechanical stability of scanning systems, high positioning accuracy of the probing electromagnetic beam and efficient collection of the scattered radiation. The apparatus allows surface defect classification, determining defect dimensions and convenient automation of inspection.

Method for correcting a reflective optical element for the wavelength range between 5 nm and 20 nm
10809630 · 2020-10-20 · ·

A method for correcting a reflective optical element for the wavelength range between 5 nm and 20 nm, which includes a multilayer system on a substrate. The multilayer system has layers consisting of at least two alternately arranged different materials with a different real component of the refractive index for a wavelength in the extreme ultraviolet wavelength range. The method includes: measuring the reflectivity distribution over the surface of the multilayer system; comparing the measured reflectivity distribution to a nominal distribution of the reflectivity over the surface of the multilayer system, determining at least one partial surface having a measured reflectivity above the nominal reflectivity; and irradiating the at least one partial surface with ions or electrons.

SINGLE-SHOT, ADAPTIVE METROLOGY OF ROTATIONALLY VARIANT OPTICAL SURFACES USING A SPATIAL LIGHT MODULATOR
20200326182 · 2020-10-15 ·

Single-shot, adaptive metrology of rotationally variant optical surfaces, such as toroids, off-axis conies and freeform surfaces. An adaptive interferometric null test uses a high definition liquid crystal phase-only spatial light modulator (SLM) as the reconfigurable null element, on which a simulated nulling phase function is encoded, based on the specifications of the surface under test to generate a null interferogram. The power component of the surface sag is nulled by system design, not the SLM, enabling the SLM to fully compensate the residual departure without the need to tilt the optic or use a custom Offner-null. By wrapping the phase function at multiples of 2*pi radian, the upper limit in sag of the optic under test is theoretically removed.

TESTING OF CURVED X-RAY GRATINGS

The present invention relates to a method, and a corresponding device, for testing a radius of curvature and/or for detecting inhomogeneities of a curved X-ray grating for a grating-based X-ray imaging device. The method comprises generating a beam of light diverging from a source point, propagating along a main optical axis and having a line-shaped beam profile. The method comprises reflecting the beam off a concave reflective surface of the grating. A principal axis of the concave reflective surface coincides with the main optical axis and the source point is at a predetermined distance from a point where the main optical axis intersects the concave reflective surface. The method comprises determining whether a projection of the reflected beam in a plane at or near the source point is present outside a central region around the source point, in which an absence of this projection outside the central region indicates that a radius of curvature of the concave reflective surface corresponds to the predetermined distance and/or that the reflective surface is substantially homogeneously curved along a curve formed by the beam impinging on the concave reflective surface.

ELECTRICAL INSPECTION METHOD

An electrical inspection method includes: a step of preparing a wafer in which a plurality of Fabry-Perot interference filter portions is formed, each of the plurality of Fabry-Perot interference filter portions in which a distance between a first mirror portion and a second mirror portion facing each other varies by an electrostatic force; and a step of inspecting electrical characteristics of each of the plurality of Fabry-Perot interference filter portions.

Evolute tester for optical surfaces
10788634 · 2020-09-29 ·

Systems and methods for testing and characterization of optical surfaces which works equally well on concave, flat, convex, and non-conic optical surfaces, and which does not require that a master surface be first produced. The method is automatic and requires little human intervention. It provides an extremely high degree of accuracy, and provides repeatability of measurements within a minuscule tolerance of error. The method determines the evolute of the surface automatically, deterministically, and repeatably via orthogonal reflection by ascertaining the evolute of the surface's figure along multiple diameters of the surface.

Integrated optical probe card and system for batch testing of optical MEMS structures with in-plane optical axis using micro-optical bench components

Aspects relate to an integrated optical probe card and a system for performing wafer testing of optical micro-electro-mechanical systems (MEMS) structures with an in-plane optical axis. On-wafer optical screening of optical MEMS structures may be performed utilizing one or more micro-optical bench components to redirect light between an out-of-plane direction that is perpendicular to the in-plane optical axis to an in-plane direction that is parallel to the in-plane optical axis to enable testing of the optical MEMS structures with vertical injection of the light.

OPTICAL INSPECTION DEVICE AND OPTICAL INSPECTION METHOD

An optical inspection device includes: a wafer support unit configured to support a wafer in which a plurality of Fabry-Perot interference filter portions are formed, each of the plurality of filter portions in which a distance between the first mirror portion and the second mirror portion facing each other varies by an electrostatic force, the wafer support unit configured to support the wafer such that a direction in which the first mirror portion and the second mirror portion face each other follows along a reference line; a light emission unit configured to emit light to be incident on each of the plurality of filter portions along the reference line; and a light detection unit configured to detect light transmitted through each of the plurality of filter portions along the reference line. The wafer support unit has a light passage region that allows light to pass along the reference line.