Provided is an interferometer for inspecting a test sample. The interferometer includes: a light source for providing a light beam; a beam splitting element, splitting the light beam into first and second incident light, wherein the first incident light is reflected by the test sample into first reflection light; a reflecting element, reflecting the second incident light into second reflection light; an optical detection element, receiving the first and the second reflection light into an interference signal; and a signal processing module, coupled to the optical detection element, for performing spatial differential calculation on the interference signal to generate a demodulation image of the test sample.

Apparatus, systems and methods associated with a pressure-balanced seismic sensor package are disclosed. One example of an apparatus can include a plurality of optical components, a sensor box enclosing the plurality of optical components, and a lid for the sensor box. The plurality of optical components, the sensor box, and the lid form a pressure-balanced seismic sensor package.

An optimization apparatus for a camera system having lenses with at least one non-uniform parameter and a method to design them is disclosed. When the non-uniform parameter of the lenses is the presence of optical distortion, the image of the objects inside the optimization apparatus are deformed. Embodiments of the invention allow designing of optimization apparatuses using 2D or 3D objects pre-distorted according to the exact distortion profile of the lens. When viewed by a camera system with a lens having optical distortion, the image of the pre-distorted apparatus appears undistorted, and can be automatically analyzed with existing software programs or be compared to existing images by human observers.

An inspection apparatus (300) includes a focus monitoring arrangement (500, 500). Focusing radiation (505) comprises radiation having a first wavelength and radiation having a second wavelength. Reference radiation and focusing radiation at each wavelength are provided with at least one relative frequency shift so that the interfering radiation detected in the detection system includes a time-varying component having a characteristic frequency. A focus detection system (520) comprises one or more lock-in detectors (520b, 520c, 900). Operating the lock-in detectors with reference to both the first and second characteristic frequencies allows the arrangement to select which of the first and second focusing radiation is used to determine whether the optical system is in focus. Good quality signals can be obtained from targets of different structure.

A method for measuring an angularly resolved intensity distribution in a reticle plane (24) of a projection exposure apparatus (10). The apparatus includes an illumination system (16), irradiating a reticle (22) arranged in the reticle plane (24) and having a first pupil plane (20). All planes of the projection exposure apparatus which are conjugate thereto are further pupil planes, and the reticle plane (24) and all planes which are conjugate thereto are field planes. The method includes: arranging a spatially resolving detection module (44) in the region of one of the field planes (24, 30) such that the detection module is at a smaller distance from this field plane than from the closest pupil plane (20), radiating electromagnetic radiation (21) onto an optical module (42) from the illumination system, and determining an angularly resolved intensity distribution of the radiation from a signal recorded by the detection module.

Provided is an optical coordinate measuring device with improved measurement efficiency. A holding part of a measurement head includes an installation part and a stand part. The installation part has a horizontal flat shape and is installed on the installation surface. The stand part is provided so as to extend upward from one end of the installation part. The placement table is provided at the other end of the installation part. A measurement target is placed on the placement table. A main imaging unit is provided on an upper part of the stand part. The main imaging unit is arranged so as to be turned obliquely downward such that it can capture an image of a previously set imaging region above the placement table.

Provided is an optical coordinate measuring device with improved measurement efficiency. A holding part of a measurement head includes an installation part and a stand part. The installation part has a horizontal flat shape and is installed on the installation surface. The stand part is provided so as to extend upward from one end of the installation part. The placement table is provided at the other end of the installation part. A measurement target is placed on the placement table. A main imaging unit is provided on an upper part of the stand part. The main imaging unit is arranged so as to be turned obliquely downward such that it can capture an image of a previously set imaging region above the placement table.

An instrument has a light-emitting and light-receiving assembly including an image capture unit and image processing unit; a backscatterer and an opening provided therein; a support for receiving an ophthalmic lens between the assembly and backscatterer, the assembly, support and backscatterer placed so that an incident light beam traverses the lens, strikes the backscatterer, returns and re-traverses the lens to arrive at the capture unit; the light-receiving assembly, the support, backscatterer and opening configured so that the assembly receives light from the beam; and the opening and a drive device for cyclically driving and making the backscatterer perform an identical movement in each cycle, configured so that a fixed zone opposite the backscatterer includes at least one part of which, over the course of a cycle, every point is at times perpendicular to the opening and at times perpendicular to a solid portion part of the backscatterer.

A measuring instrument is configured to detect a displacement of a contact point provided to be movable and to digitally display a measured value on a display unit provided on an outer surface of a case. The measuring instrument includes an input unit. The input unit is provided on the outer surface of the case and is configured to allow a user to input to the input unit through a manual operation. The input unit includes a sensor which is configured to detect an amount of operation and a speed of operation. The amount of operation is converted into a conversion value in view of the speed of operation and then is displayed on the display unit.

In a method for measuring the positions of centers of curvature of optical surfaces of a single- or multi-lens optical system, an imaging lens system images an object plane into a first and a second image plane. The first image plane is produced by a first ancillary lens system having a first focal length and defining a first beam path, while the second image plane is produced by a second ancillary lens system having a second focal length that is different from the first focal length and defining a second beam path that is different from the first beam path. An object arranged in the object plane is then imaged simultaneously or sequentially at the first and the second image plane by means of measuring light. Reflections of the measuring light at optical surfaces of the optical system are detected by means of a spatially resolving light sensor. The actual positions of the first and the second center of curvature are calculated from the detected reflexes.