The invention relates to a method for determining the thickness of a contaminating layer and/or the type of a contaminating material on a surface (7) in an optical system, in particular on a surface (7) in an EUV lithography system, comprising: irradiating the surface (7) on which plasmonic nanoparticles (8a,b) are formed with measurement radiation (10), detecting the measurement radiation (10a) scattered at the plasmonic nanoparticles (8a,b), and determining the thickness of the contaminating layer and/or the type of the contaminating material on the basis of the detected measurement radiation (10a). The invention also relates to an optical element (1) for reflecting EUV radiation (4), and to an EUV lithography system.

The present disclosure relates to a method for determining an impact of optical component degradation on the functionality of an electro-optical sensor system, said method (100) comprising a step of obtaining (110) test data relating to the state of the optical component; a step of providing (130) a set of correlation values based on test data and correlation data, said correlation data correlating test data to an optical component degradation state, wherein the optical component degradation state relates to a functionality impact of the electro-optical sensor system; and a step of obtaining (140) an electro-optical sensor system functionality estimate based on the provided set of correlation values.

Methods and apparatus for evaluating the geometric properties of optical fiber preforms, which methods include: providing an optical fiber preform having a longitudinal axis, an outer diameter and a circumference; providing a two-dimensional pattern having a length parallel to the longitudinal axis of the preform and a width greater than the outer diameter of the preform; providing an image capturing device disposed such that the preform is aligned between the pattern and the image capturing device; rotating the preform about its longitudinal axis and acquiring a first plurality of images of the pattern viewed through the preform at at least two different points along the circumference of the preform; and determining at least one geometric property of the preform from the first plurality of images.

An extreme ultraviolet (EUV) collector inspection apparatus and method capable of precisely inspecting a contamination state of an EUV collector and EUV reflectance in accordance with the contamination state are provided. The EUV collector inspection apparatus includes a light source arranged in front of an EUV collector to be inspected and configured to output light in a visible light (VIS) band from UV rays, an optical device configured to output narrowband light from the light, and a camera configured to perform imaging from an UV band to a VIS band. An image by wavelength of the EUV collector is obtained by using the optical device and the camera and a contamination state of the EUV collector is inspected.

The defect size of a photomask blank is evaluated. An inspection-target photomask blank is irradiated with inspection light and reflected light of the region of the inspection-target photomask blank irradiated with the inspection light is collected through an objective lens of an inspection optical system as a magnified image of the region. Then, an intensity change part in the light intensity distribution profile of the magnified image is identified. Next, a difference in the light intensity of the intensity change part is obtained and the width of the intensity change part is obtained as the apparent width of the defect. Then, the width of the defect is calculated on the basis of a predetermined conversion expression showing the relationship among the difference in the light intensity, the apparent width of the defect, and the actual width of the defect, and the width of the defect is estimated.

A method for detecting damage to a converter device of a lighting apparatus is provided. The method may include irradiating the converter device with input light, detecting a useful light portion emitted principally by a first section of the converter device by means of a first sensor element. A first detection signal is obtained, detecting a useful light portion emitted principally by a second section of the converter device, said second section being different than the first section, by means of a second sensor element. A second detection signal is obtained. The method further may include automatically obtaining damage information about the converter device from a ratio or a difference of the first detection signal with respect to either the second detection signal or a comparison signal formed therefrom.

An apparatus includes a lighting unit configured to irradiate a light emitting device package including a light transmitting resin containing a light conversion material with light having a certain color; a camera configured to capture an image of the light emitting device package; and a controller configured to determine color coordinates of the light emitting device package using the image, captured by the camera, to determine whether the light emitting device package is defective.

Device of inspection of an inner surface of a hollow body comprising an emitter (1) and a receiver (3) of a line of light (L1, L2), a tube (8) which is configured for being housed in the hollow body during the inspection, and optical means comprising at least one mirror (4, 5) which is arranged inside the upper end (9) of the tube (8), and mirrors (6, 7) which are arranged inside the lower end (10) of the tube (8), the mirror (4 or 5) is facing one opening (11) of the upper end (9) for reflecting the line (L1) emitted by the emitter (1) and directing it towards the mirror (6), or it is facing another opening (12) of the upper end (9) for receiving the line (L2) reflected by the inner surface from the mirror (7) and directing it towards the receiver (3), the mirror (6) is facing one opening (13) of the lower end (10) for receiving the line (L1) emitted by the emitter (1) and directing it onto the inner surface, and the mirror (7) is facing the opening (13) of the lower end (10) for reflecting the line (L2) reflected by the inner surface and directing it towards the receiver (3).

A control system to control the quality of at least one reflector body of a lamp of a motor vehicle, comprising a light source, which is designed to emit a first light beam to irradiate the reflecting surface of the reflector body; an image capturing apparatus, which is arranged so as to capture a series of images) containing the irradiated reflecting surface of the reflector body; a processing device, which is configured so as to process the images), in order to determine the actual reflectance of the reflector body, and so as to determine a quality condition of the reflector body to be validated based on the actual reflectance.

The present disclosure relates to a method for determining an impact of optical component degradation on the functionality of an electro-optical sensor system, said method (100) comprising a step of obtaining (110) test data relating to the state of the optical component; a step of providing (130) a set of correlation values based on test data and correlation data, said correlation data correlating test data to an optical component degradation state, wherein the optical component degradation state relates to a functionality impact of the electro-optical sensor system; and a step of obtaining (140) an electro-optical sensor system functionality estimate based on the provided set of correlation values.