Abstract: The present invention relates to the field of optical probe surface inspection by interferometry, and in particular to a method and a respective apparatus for fine-controlling the position of a predetermined probe location (21) relative to a fixed reference point (12) of a probe processing apparatus fixedly coupled to an auxiliary optical laser apparatus, in which method the position is controlled with optical means. In order to simplify the apparatus it is proposed to provide a simply structured fine-control positioning system also based on the principle of interferometry. Basically, a lens-less optical arrangement is provided which uses a collimated input laser beam (10) and thus presetting said probe location position within a predetermined converging range of ¼ of the wave length of the applied fine-controlling positioning laser beam (10).

Abstract: The present invention features an anamorphic apparatus that alters a wavefront of a beam having a wavefront error to form a beam comprising a region having a greatly reduced wavefront error. A beam stop may be used with the anamorphic apparatus to define a portion of the region having a greatly reduced wavefront error that is subsequently detected or launched into a fiber optic. Furthermore, the anamorphic apparatus can be incorporated into an interferometry system to reduce errors associated with wavefront error and beam shear, i.e., non-cyclic non-linearities.

Abstract: An imaging system with built-in diagnostics and preferably implemented as an integrated system-on-a-chip (SOC) imaging system. According to one implementation of the present invention, the imaging system can be operated in two operating modes: a normal operating mode and a special diagnostic mode. While running in the diagnostic mode, the imaging system can be configured to detect manufacturing defects. The imaging system can be further configured to compensate for certain types of manufacturing defects. While running in the diagnostic mode, the imaging system (1) identifies pixels that function incorrectly and (2) creates a record of such pixels. In the normal operating mode, the imaging system can use the record to compensate for the missing or incorrect data from these defective pixels during real-time image processing. The present invention simplifies testing of imaging systems and/or image sensors. It also increases manufacturing yield and, therefore, results in lower per-unit manufacturing cost.

Abstract: The invention measures a thickness variation at a high accuracy around a wide range of a thin plate by a comparatively large spot diameter between 0.5 mm and 2 mm. A polarization beam splitter separating a laser beam emitted from a laser generator and transmitting through an isolator into a measurement light and a reference light is provided. A quarter wavelength plate is provided between the polarization beam splitter and a measurement surface, and between the polarization beam splitter and a reference surface. A focusing and reflecting means for focusing and reflecting the measurement light reflected by the measurement surface and reflected by the polarization beam splitter, and the reference light reflecting by the reference surface and transmitting through the polarization beam splitter is provided. A half mirror reflecting the measurement light and the reference light which return from the polarization beam splitter is provided.

Abstract: A first polarizing beam splitter splits the light emitted by a light source into a measurement beam and a reference beam. The reference beam is returned by a second polarizing beam splitter and an optical member which is constituted by a right angle prism and a pentaprism, reenters the first polarizing beam splitter via a half wavelength plate and guided to a detector. On the other hand, the measurement beam is reflected by a corner mirror, is returned by the second polarizing beam splitter and the optical member, is reflected by the corner mirror again, reenters the first polarizing beam splitter via a half wavelength plate and guided to the detector. The optical member returns the measurement beam such that the measurement beam exits at the different point from the incident point and that light rays incident thereon in a state shifted from each other are returned with the shifted direction and shifted amount between each light rays kept unchanged.

Abstract: A method and device for measuring cell gap of a liquid crystal display, the display comprising a pair of substrates with electrodes adhered together forming a predetermined sized cell gap. The device and method includes radiating near-infrared light toward the liquid crystal cell, reflectively interfering the near-infrared light by the cell gap, and analyzing the interference waveform to compute the cell gap size. The device may include an X-Y stage, an FT-NIR spectroscope using near-infrared light as light source, a detector unit for detecting reflected interference light from the liquid crystal cell, and an analyzing computer unit for analyzing and computing cell gap by performing Fourier transformation method or maximum entropy method (MEM) to the interference fringe spectrum.

Abstract: A method and fly-height tester include a moving medium and a slider mount that holds a slider in proximity with the medium so that the slider flies relative to the medium. At least one light emitting diode generates a light that is directed by optics so that it reflects off the medium and the slider. The reflected light is directed by second optics to at least one detector, where each detector is capable of generating an electrical signal based on the amplitude of at least one wavelength of light in the reflected light. A distance calculator then determines the distance from the slider to the medium based on the at least one electrical signal.

Abstract: A process for forming a thin film is described that enables automatic formation of thin films having constant optical properties reliably and in large quantities with excellent reproducibility suitable for mass production. An apparatus for performing the process is also described. Generally, a material for vapor deposition is vaporized by an electron gun and an antireflection film forms by vapor deposition on lenses held by a coat dome. The electric power applied to the electron gun is controlled so that the amount of transmitted or reflected light continuously measured by an optical film thickness meter during thin film formation is compared to a reference amount of measured light stored in a means for storing data until the measured and reference amounts of measured light are close to, or the same as, one another.

Abstract: A system for evaluating a donor cornea includes a light source for generating a beam having a predetermined characteristic and a selected configuration. The light beam characteristic can be collimated light (wavefront analysis), white light (spectral analysis), or polarized light (polarization analysis). The beam configuration can be either circular in cross-section, or it can be a slit. When circular, the light beam is transmitted through the entire cornea to identify changes in the characteristics of the light (e.g. phase shift, spectral shift, or polarization changes). These changes then determine the optical properties of the donor cornea. When configured as a slit, the light is scattered off-axis and used to measure dimensions for a profile of the donor cornea. A computer then prepares an evaluation which includes information on both the optical qualities and the dimensional profile of the donor specimen.

Abstract: The present invention relates in general to detection of an alignment mark on a workpiece. More particularly, interferometry is applied to detect alignment signals from the surface of a workpiece such as a wafer or reticle. Other aspects of the present invention are reflected in the detailed description, figures and claims.

Abstract: A position detecting method and position detecting system, for measuring a position of a pattern formed on an object to be observed, for use in an exposure apparatus. The method includes providing incoherence-transformed illumination light for illuminating the pattern surface of the object by use of coherent light, and incoherence-transformed reference light, changing the quantity of the reference light in accordance with a reflection factor of the pattern surface, imaging reflection light from the pattern surface and reference light reflected by a conjugate mirror, together, upon a photoelectric converting element, and measuring the position of the pattern on the basis of an interference image signal obtainable by the imaging.

Abstract: A manufacturing method for rhomboid assemblies cuts stacks of glass plates that are glued together with coatings between the glass plates. The cuts are at an angle such as 45° and surfaces resulting from the cuts are finished to optical tolerances. These optical surfaces permit attachment of rhomboid assemblies directly to optical elements such as a polarizing beam-splitter (PBS) in a multi-axis interferometer. Further, elements such as quarter-wave plates, cube corner reflectors, and rhomboid elements that extend the separation of measurement beams can be attached to the PBS to provide integrated beam optics that are compact and thermally stable. Placing a reflective coating or other reference reflector on a quarter-wave plate for the reference beam can keep the entire beam path for the reference beam within the integrated structure. When rhomboid elements extend the separation between measurement beams, an extension to the PBS can match the optical path lengths of reference and measurement beams.

Abstract: According to the present invention, it is adapted to calculate simultaneously an absolute molecular orientation with an effective second order nonlinear optical constant in an object to be measured without changing a measuring point. Further, in order that a period of time required for measuring an absolute molecular orientation and an effective second order nonlinear optical constant in an object to be measured is reduced, whereby a possibility of damaging the object to be measured can be minimized, measurement is carried out by the use of a single light source in accordance with SHG phase method without shifting the measuring point of the; object to be measured, so that the absolute molecular orientation and the effective second order nonlinear optical constant can be calculated from a fitting curve achieved as a result of fitting the fringe obtained by the above described measurement.

Abstract: The invention measures a thickness variation at a high accuracy around a wide range of the thin plate by a comparatively large spot diameter between 0.5 mm and 2 mm. A polarization beam splitter separating a laser beam emitted from a laser generator and transmitting through an isolator into a measurement light and a reference light is provided. A quarter wavelength plate is provided between the polarization beam splitter and a measurement surface, and between the polarization beam splitter and a reference surface. A focusing and reflecting means for focusing and reflecting the measurement light reflecting by the measurement surface and reflecting by the polarization beam splitter, and the reference light reflecting by the reference surface and transmitting through the polarization beam splitter is provided. A half mirror reflecting the measurement light and the reference light which return from the polarization beam splitter is provided.

Abstract: An in-focus image of an information-bearing region within and/or on a substance is discriminated from an out-of-focus image so as to reduce errors in image information of the substance by producing a probe beam and a reference beam from a wideband point source, producing antisymmetric spatial properties in the reference beam, converting the probe beam to a beam focused to a line in the region, producing an in-focus return probe beam, and producing antisymmetric spatial properties in the in-focus return probe beam. Then the in-focus return probe beam is spatially filtered and focused to a line image in a detector plane of a detector system. The reference beam is spatially filtered and focus to a line image in the detector plane. A beam from an out-of focus image point is spatially filtered. The line image of the spatially filtered reference beam is interfered with the spatially filtered beam from the out-of-focus image point and the line image of the spatially filtered in-focus return probe beam.

Abstract: The surface form of a semiconductor thin film such as a polysilicon film 13 formed on a semiconductor substrate 11 is measured through spectro-ellipsometry or measured by performing an IPA quantitative analysis through GC. Mass (gas chromatography) after exposing the semiconductor thin film to IPA (isopropyl alcohol) vapor and drying the semiconductor thin film. Through either of these methods the surface form of the polysilicon film easily and quickly measured.

Abstract: Optical components, particularly microoptic glass components used in synthesizing birefringence in filter systems based on polarization interferometer techniques, are fabricated using systems and methods which provide accurate frequency periodicity measurements. These measurements are derived from differential delays induced by in-process glass elements between beam components in a polarization interferometer unit and from progressive wavelength scanning across a wavelength band of interest. The consequent sinusoidal output variation has peak to peak spacings which are measured to provide frequency periodicity values from which precise length corrections for the optical elements can be calculated.

Abstract: A Wollaston prism phase-stepping point diffraction interferometer for testing a test optic. The Wollaston prism shears light into reference and signal beams, and provides phase stepping at increased accuracy by translating the Wollaston prism in a lateral direction with respect to the optical path. The reference beam produced by the Wollaston prism is directed through a pinhole of a diaphragm to produce a perfect spherical reference wave. The spherical reference wave is recombined with the signal beam to produce an interference fringe pattern of greater accuracy.

Abstract: An optical monitoring instrument monitors etch depth and etch rate for controlling a wet-etching process. The instrument provides means for viewing through the back side of a thick optic onto a nearly index-matched interface. Optical baffling and the application of a photoresist mask minimize spurious reflections to allow for monitoring with extremely weak signals. A Wollaston prism enables linear translation for phase stepping.

Abstract: An apparatus and method for performing optical coherence domain reflectometry. The apparatus preferably includes a single output light source to illuminate a sample with a probe beam and to provide a reference beam. The reference beam is routed into a long arm of an interferometer by a polarizing beamsplitter. A reflected beam is collected from the sample. A 90° double pass polarization rotation element located between the light source and the sample renders the polarizations of the probe beam and reflected beam orthogonal. The polarizing beamsplitter routes the reflected beam into a short arm of the interferometer. The interferometer combines the reference beam and the reflected beam such that coherent interference occurs between the beams. The apparatus ensures that all of the reflected beam contributes to the interference, resulting in a high signal to noise ratio.

Abstract: An apparatus and method for performing optical coherence domain reflectometry. The apparatus preferably includes a single output light source to illuminate a sample with a probe beam and to provide a reference beam. The reference beam is routed into a long arm of an interferometer by a polarizing beamsplitter. A reflected beam is collected from the sample. A 90° double pass polarization rotation element located between the light source and the sample renders the polarizations of the probe beam and reflected beam orthogonal. The polarizing beamsplitter routes the reflected beam into a short arm of the interferometer. The interferometer combines the reference beam and the reflected beam such that coherent interference occurs between the beams. The apparatus ensures that all of the reflected beam contributes to the interference, resulting in a high signal to noise ratio.

Abstract: An apparatus and method for performing optical coherence domain reflectometry. The apparatus preferably includes a single output light source to illuminate a sample with a probe beam and to provide a reference beam. The reference beam is routed into a long arm of an interferometer by a polarizing beamsplitter. A reflected beam is collected from the sample. A 90° double pass polarization rotation element located between the light source and the sample renders the polarizations of the probe beam and reflected beam orthogonal. The polarizing beamsplitter routes the reflected beam into a short arm of the interferometer. The interferometer combines the reference beam and the reflected beam such that coherent interference occurs between the beams. The apparatus ensures that all of the reflected beam contributes to the interference, resulting in a high signal to noise ratio.