A method for inspecting a spatial light modulator includes: performing such control that in an inspection target area in an array of mirror elements, the mirror elements in a first state in which incident light is given a phase change amount of 0 and the mirror elements in a second state in which incident light is given a phase change amount of 180 () become arrayed in a checkered pattern; guiding light having passed the inspection target area to a projection optical system with a resolution limit coarser than a width of an image of one mirror element, to form a spatial image; and inspecting a characteristic of the spatial light modulator from the spatial image. This method allows us to readily perform the inspection of the characteristic of the spatial light modulator having the array of optical elements.

Provided is a position detection method including splitting detection light into first and second light, the first light being incident on a returning optical path, a portion of the first light being transmitted through a beam splitter and a remaining portion of the first light being reflected by the beam splitter to reach the beam splitter through a movable mirror every time the first light reaches the beam splitter through the movable mirror, combining the first light transmitted though the beam splitter and the second light to generate multiple interference light, extracting a second interference light signal having a wavelength of 1/p (p is a natural number) of a wavelength of detection light from a first interference light signal of the multiple interference light, and calculating a position of the movable portion in a predetermined direction based on the second interference light signal.

A system may include a wafer that includes ICs and defines cavities. Each cavity may be formed in a BEOL layer of the wafer and proximate a different IC. The system may also include an interposer that includes a transparent layer configured to permit optical signals to pass through. The interposer may also include at least one waveguide located proximate the transparent layer. The at least one waveguide may be configured to adiabatically couple at least one optical signal out of the multiple ICs. Further, the interposer may include a redirecting element optically coupled to the at least one the waveguide. The redirecting element may be located proximate the transparent layer and may be configured to receive the at least one optical signal from the at least one waveguide. The redirecting element may also be configured to vertically redirect the at least one optical signal towards the transparent layer.

A visual inspection apparatus of the present invention includes a rotational portion configured to rotate in a state that an inspection target is placed on the rotational portion, a mirror portion provided so as to reflect the inspection target in the state that the inspection target is placed on the rotational portion, an imaging portion configured to image the inspection target reflected in the mirror portion, an adjustment portion configured to change an imaging angle of the imaging portion relative to the inspection target reflected in the mirror portion, and an inspection portion configured to inspect a surface of the inspection target based on image data captured by the imaging portion.

An apparatus for detecting defects includes a first conveyor for transporting finished reflective elements; a 3D inspection zone including a second conveyor, a first robot for picking one reflective element and placing same on the second conveyor, two side-lit panels at either side of the second conveyor, and two first digital cameras each between the side-lit panels of the same side for taking 3D images of the reflective element and sending same to an image processor for detecting defects; a 2D inspection zone including a third conveyor for receiving the reflective element, a backlit panel at either side of the third conveyor, and two second digital cameras for taking 2D images of the reflective element and sending same to the image processor for detecting defects. There are further provided a microcontroller, a fourth conveyor, a fifth conveyor, and a second robot.

The present disclosure provides a method for processing defect information of a product, which includes the following steps of: acquiring defect information on a current film layer and defect information on historical film layers; determining whether defect information exists at a target location of the historical film layer if defect information exists at a target location of the current film layer; if defect information exists for a corresponding location to the target location in at least one of the historical film layers, deleting the defect information detected at the target location in the current film layer; and if no defect information exists for the target location in any of the historical film layers, retaining the defect information detected at the target location in the current film layer. According to this, for the defect information on the current film layer, only the defect information caused by factors of the current film layer may be retained, and the defect information caused by the historical film layers will not be retained, and thus, on the one hand, the stored data volume may be reduced, and on the other hand, the complexity of subsequent analysis of defect information may be simplified.

A method of optical device metrology is provided. The method includes introducing a first type of light into a first optical device during a first time period, the first optical device including an optical substrate and an optical film disposed on the optical substrate, the first optical device further including a first surface, a second surface, and one or more sides connecting the first surface with the second surface; and measuring, during the first time period, a quantity of the first type of light transmitted from a plurality of locations on the first surface or the second surface during the first time period, wherein the measuring is performed by a detector coupled to one or more fiber heads positioned to collect the light transmitted from the plurality of locations.

A system (100) and method can monitor a reflectance of a mirror target that includes at least one curved mirror (M). The system (100) can take a first irradiance measurement of the sun (S), the first irradiance measurement representing a direct solar irradiance. The system (100) can take a second irradiance measurement that represents an irradiance from a reflection of the sun (S) from the mirror target plus background irradiance from a reflection of the sky from the mirror target. The system (100) can take a third irradiance measurement that represents the background irradiance from the reflection of the sky from the mirror target. The system (100) can determine a reflectance of the mirror target from the first, second, and third irradiance measurements. The system (100) can compare the reflectance to a specified reflectance threshold, and, upon determining that the reflectance of the mirror target is less than the specified reflectance threshold, can generate an alert signal.

A method of optical device metrology is provided. The method includes introducing a first type of light into a first optical device during a first time period, the first optical device including an optical substrate and an optical film disposed on the optical substrate, the first optical device further including a first surface, a second surface, and one or more sides connecting the first surface with the second surface; and measuring, during the first time period, a quantity of the first type of light transmitted from a plurality of locations on the first surface or the second surface during the first time period, wherein the measuring is performed by a detector coupled to one or more fiber heads positioned to collect the light transmitted from the plurality of locations.

A defects evaluation system and method are provided in the present invention. Based on the principle of the microscopic scattering dark-field imaging, the present invention implements a sub-aperture scanning for the surface of spherical optical components and then obtains surface defects information with image processing. Firstly, the present invention takes full advantage of the characteristic that the surface defects of spherical optical components can generate scattering light when an annular illumination beam irradiates on the surface, to implement the sub-aperture scanning and imaging that covers the entire spherical surface. Then, a series of procedures such as the global correction of sub-apertures, the 3D stitching, the 2D projection and the digital feature extraction are taken to inspect spherical surface defects. Finally, actual size and position information of defects are evaluated quantitatively with the defects calibration data. The present invention achieves the automatic quantitative evaluation for surface defects of spherical optical components, which considerably enhance the efficiency and precision of the inspection, avoiding the influence of subjectivity on the results. Eventually, reliable numerical basis for the use and process of spherical optical components is provided.