Abstract: An apparatus for characterizing multilayer samples is disclosed. An intensity modulated pump beam is focused onto the sample surface to periodically excite the sample. A probe beam is focused onto the sample surface within the periodically excited area. The power of the reflected probe beam is measured by a photodetector. The output of the photodetector is filtered and processed to derive the modulated optical reflectivity of the sample. Measurements are taken at a plurality of pump beam modulation frequencies. In addition, measurements are taken as the lateral separation between the pump and probe beam spots on the sample surface is varied. The measurements at multiple modulation frequencies and at different lateral beam spot spacings are used to help characterize complex multilayer samples. In the preferred embodiment, a spectrometer is also included to provide additional data for characterizing the sample.

Abstract: A method for imaging surface topography is based on Total Internal Reflection (TIR) and is particularly useful for imaging surface topography of wafers used in the manufacture of integrated circuits. This surface topography includes scratches, which are more localized, and dishing, which is a gentle dip over a larger area. In practice, a wafer is placed with the surface of interest in close contact with a prism or other internal reflection element (IRE). Light of suitable wavelength is incident at a suitable incident angle through the IRE of suitable refractive index in order to allow total internal reflectance at the surface of the IRE in close contact with the wafer surface. The reflected beam is then imaged to give a map of the location and dimensions, and some information on the depth, of the various surface features on the wafer.

Abstract: A spectrometric method is disclosed which uses a novel tunable laser as a monochromatic light source to carrying out spectrometry efficiently. As the tunable laser, a tunable laser is used which comprises a laser resonator so provided therein with a laser medium 14 capable of laser oscillation in a predetermined range of wavelength and a birefringent acousto-optic element 100 and which is capable of wavelength selection by selecting a frequency of an acoustic wave to be generated in the birefringent acousto-optic element 100 by means of a piezoelectric element 22 connected to a RF power source 20. The tunable laser is used instead of a spectroscopic light source and a monochromator in a conventional spectrophotometer to thereby carry out spectrometry efficiently.

Abstract: A method and apparatus for inspecting the quality of transparent protective overlays. The inspection method and apparatus enables accurate inspection of formed transparent protective overlays and enables implementation of more quantitative control of transparent protective overlay quality. Such method and apparatus automatically and accurately inspects the quality of transparent protective overlays placed on substrate surfaces to determine whether the transparent protective overlay formed to protect information such as images, text, or symbols recorded on the surface of a card-type or other easily portable information-recorded medium is of acceptable quality.

Abstract: A device to measure the relative location in three dimensional space of anatomical structures by injecting a beam of light into an optical imaging device and projecting the beams of light onto the object being imaged. By virtue of the change in the image of the light beam, as a function of changes in the position and/or direction of the injected beam, and knowing the optical transfer function of the imaging device, the position of the anatomical structure can easily be calculated.

Abstract: A combination of an optically transmissive dielectric fluid having a first refractive index and an optically anisotropic particle rotatably disposed in the fluid is provided. The particle has at least one optically transmissive region having a second refractive index. The particle provides a first optical modulation characteristic when disposed in the fluid in a first orientation with respect to a flux of optical energy, and further provides a second optical modulation characteristic when disposed in the fluid in a second orientation with respect to a flux of optical energy. The particle has an anisotropy for providing an electrical dipole moment, the electrical dipole moment rendering the particle electrically responsive such that when the particle is rotatably disposed in an electric field while the electrical dipole moment of the particle is provided, the particle tends to rotate to an orientation in which the electrical dipole moment aligns with the field.

Abstract: This invention provides an exposure mask including a translucent film formed on a light-transmitting substrate and having a mask pattern, and a stabilized region formed in the boundary between the light-transmitting substrate and the translucent film or on at least the surface of the translucent film to prevent variations in physical properties of the translucent film.

Abstract: The process uses information from the scan sweeps of a laser scanner, and readings with a CCD reader, to obtain a series of stipulated areas corresponding to successive cross-sections of the object as reckoned by moving the object relative to the scanner and the reader. The volume is then obtained by multiplying each of said areas by the feed distance of the object. The possibility is further contemplated of accommodating the slope angles of the scan plane and the read plane, or alternatively neglecting their effects if said angles are sufficiently small. The volume measurement may be accompanied by the reading of an optical code provided on the object.

Abstract: A method and apparatus for measuring injection bores of fuel injection valves for internal combustion engines, in which the injection valve including the bores to be measured is fastened in a receiving device and the bore is measured with a measuring device. The ascertainment of the location and geometry of the bore to be measured is done by means of an optoelectronic measuring method such as a camera.

Abstract: The present invention discloses a mask defect inspection apparatus for optically detecting a defect on a mask having a circuit pattern, which comprises an illumination system for illuminating the mask with inspection light; a first light receiving optical system for receiving the inspection light reflected by the mask; a second light receiving optical system for receiving the inspection light transmitted by the mask; a first spatial filter for shielding the inspection light passing through a central region including the optical axis of the first light receiving optical system in an optical Fourier transform plane for the circuit pattern in the first light receiving optical system; a second spatial filter for shielding the inspection light passing through a central region including the optical axis of the second light receiving optical system in an optical Fourier transform plane for the circuit pattern in the second light receiving optical system; a first detector for photoelectrically converting the inspecti

Abstract: A method for determining the fine structure of materials by means of a nonlinear scanning laser microscope, including the steps of forming an image of a specimen by scanning selected points thereof with a focusable laser beam of a predetermined fundamental frequency w, thereby exciting the points to generate signals constituting the third harmonic 3w of said fundamental frequency w, collecting the signals by collecting means, substantially filtering out from the collected 3w signals, signals of a frequency other than the third harmonic 3w, feeding the filtered 3w signals to a detector, and storing the output of the detector for processing and display. A nonlinear scanning laser microscope adapted to form an image of a specimen by scanning it point by point with a focusable laser beam of a predetermined fundamental frequency, is also provided.

Abstract: A system and method for optical interrogation and measurement of a hydrocarbon fuel gas includes a light source generating light at near-visible wavelengths. A cell containing the gas is optically coupled to the light source which is in turn partially transmitted by the sample. A spectrometer disperses the transmitted light and captures an image thereof. The image is captured by a low-cost silicon-based two-dimensional CCD array. The captured spectral image is processed by electronics for determining energy or BTU content and composition of the gas. The innovative optical approach provides a relatively inexpensive, durable, maintenance-free sensor and method which is reliable in the field and relatively simple to calibrate. In view of the above, accurate monitoring is possible at a plurality of locations along the distribution chain leading to more efficient distribution.

Abstract: An apparatus and a method are presented in order to carry out an automatic optical inspection of an off-center rotating component to be measured. Using a measurement procedure which avoids mechanical contact having a source producing parallel rays and a detecting means, the off-center rotating component is rotated about a rotational axis, whereby a motion of the detecting means is synchronized with the rotation and is carried out in such a fashion that the separation, in the direction of an optical axis, between the off-center rotating component and the detecting means remains constant. In this manner optical distortions are avoided which would otherwise occur in the optical measurement procedure.

Abstract: An improved particle lens has an axis that is shifted to follow the central ray of the beam as it is deflected through the lens creating, in effect, a variable curvilinear optical axis for the lens and introducing aberrations depending on the object size and the distance off the lens symmetry axis. These aberrations are corrected by a set of wire pairs perpendicular to the system axis to add a gradient of the z-component of the magnetic field by which aberrations are generated of the same type but opposite direction as those inherent in the system.

Abstract: An infrared energy detection system having an infrared detector and a cooling system including a fluid coolant for cooling the infrared detector. An optical system is provided for directing infrared energy from a target to the detector though an optical system. The optical system includes a housing having a plurality of stops, each one of the stops corresponding to one of a plurality of fields of view of the optical system. A first lens is fixed within the housing. A second lens is slidably mounted within the housing and engageable by the plurality of stops. The second lens has a first resting position when engaging a first one of the stops. A fluid actuator system is provided for sliding the second lens away from the first stop to a second resting position when engaging the second stop.

Abstract: A versatile photonic radio frequency (RF) oscillator employs multiple feedback loops of different delay times, including at least one optical feedback loop, to generate RF signals with ultra low phase noise, narrow spectral linewidth, and a continuous wide tuning range of high resolution. Specifically, an electro-optical modulator and a long optical fiber loop are implemented in one dual-loop system. In addition, a light beam from a light source can be directly modulated by using feedback signals from multi feedback loops to alter the electrical control signal to the light source. Furthermore, the disclosed system supports both electrical and optical RF outputs. External optical injection and electrical injection can be implemented.

Abstract: Defects in a processed or partly processed semiconductor wafer, or other similar three-dimensional periodic pattern formed on a substrate surface, are detected by light diffraction. Incident monochromatic light is provided from an elongated and extended source to illuminate the entire wafer surface. By use of automated image processing techniques, wafer macro inspection is thereby automated. The elongated and extended light source allows light at different angles to be incident upon each point of the wafer surface, thereby allowing defect detection for an entire wafer surface in a single field of view and reducing inspection time. The particular wavelength of the incident monochromatic light is predetermined to allow optimum detection of defects in the periodic pattern on the wafer, depending on the width and pitch of the features of the periodic pattern.

Abstract: Disclosed is a video-camera imaging-system lens barrel which overcomes the problem of a four-lens-group-type video-camera imaging-system lens barrel, which has a complicated structure and large size and weight due to the large number of lens groups. In a so-called two-group-type lens system, a first lens group 2 and a second lens group 3, which are in focus in an imaging plane (CCD 4) for each zoom magnification at fixed subject distances .alpha.m and .beta.m, are controlled such that they move along zoom tracking curves 1.sub.1, 1.sub.2, 1.sub.3 and 1.sub.4 which represent the paths of movement of the respective positions of the first lens group and the second lens group.

Abstract: Apparatus and method for measuring the relative distance between different areas on a remote surface or displacements of a selected area of a remote surface with respect to a measuring apparatus are provided. A laser beam is modulated at an RF frequency and focused on a selected area. The selected area is scanned by movement of a mirror and at each selected area the phase difference is measured. Digital data processing of signals derived from the source and return beams is used to provide high precision. For detecting or measuring vibration or displacement, an analog signal is obtained from a low-pass filter.

Abstract: The present invention is directed to method for manufacturing electrochromic devices using laser ablation techniques. More specifically, the present invention uses laser ablation to provide a simple, noncontact method of patterning electrochromic devices to a controlled depth, to form an electrochromically active area. Furthermore, laser patterning is conducive to the formation of multiple electrochromic devices on a single substrate.