Abstract: Apparatus and method for the monitoring of physiological parameters of a patient through the use of optical systems which do not require direct physical contact with the patient. The method and apparatus relate primarily to pulse oximetry for monitoring of pulse rate and arterial blood oxygen saturation. However, the apparatus and method of this invention are applicable to any form of optical detection of the physiological parameters in which light of any wavelength, visible or invisible, is directed from a remote instrument into a patient at a first imaging site, and subsequently collected at a second site spaced from the first site.

Abstract: An improved sensor using a gel. In one aspect, the gel is an oil plasticized thermoplastic elastomer gel. In one embodiment, the gel is mineral oil-based. The gel may be embedded on a support layer. Means for reducing shunted light from the gel are provided, such as substantially opaque material in the gel or breaks in the gel.

Abstract: A sensor probe operable to transmit light of a first wavelength for scattering by a tissue sample is described for use with a pulse oximeter designed to operate with another type of sensor probe which transmits light of a second wavelength. The sensor probe includes at least one source of light for transmitting light of the first wavelength for scattering and/or absorption by the tissue sample. At least one detector is included for detecting light of the first wavelength affected by the tissue sample and generating a signal in response thereto. An encoder in the sensor probe transforms the signal to a form which may be employed by the oximeter.

Abstract: A pulse oximeter sensor having an emitter(s) and a detector, with a layer having a first portion over the emitter and a second portion of layer over the detector is provided. A barrier is included between the first and second portions of the overlying layer to substantially block radiation of the wavelengths emitted by the emitter(s). Preferably, the barrier reduces the radiation shunted to less than 10% of the radiation detected, and more preferably to less than 1% of the radiation detected.

Abstract: The present invention provides an encoding mechanism for a medical sensor which uses a modulated signal to provide the coded data to a remote analyzer. The modulated signal could be, for instance, a pulse width modulated signal or a frequency modulated signal. This signal is amplitude independent and thus provides a significant amount of noise immunity.

Abstract: A method and apparatus for inspecting patterned transmissive substrates, such as photomasks, for unwanted particles and features occurring on the transmissive, opaque portions and at the transition regions of the opaque and transmissive portions of the substrate. A transmissive substrate is illuminated by a laser through an optical system comprised of a laser scanning system, individual transmitted and reflected light collection optics and detectors collect and generate signals representative of the light transmitted and reflected by the substrate as the substrate is scanned repeatedly in one axis in a serpentine pattern by a laser beam which is focused on the patterned substrate surface. The defect identification of the substrate is performed using only those transmitted and reflected light signals, and other signals derived from them, such as the second derivative of each of them.

Abstract: The present invention provides an encoding mechanism for a medical sensor which uses a modulated signal to provide the coded data to a remote analyzer. The modulated signal could be, for instance, a pulse width modulated signal or a frequency modulated signal. This signal is amplitude independent and thus provides a significant amount of noise immunity.

Abstract: An automated photomask inspection apparatus including an XY state (12) for transporting a substrate (14) under test in a serpentine path in an XY plane, an optical system (16) comprising a laser (30), a transmission light detector (34), a reflected light detector (36), optical elements defining reference beam paths and illuminating beam paths between the laser, the substrate and the detectors and an acousto-optical beam scanner (40, 42) for reciprocatingly scanning the illuminating and reference beams relative to the substrate surface, and an electronic control, analysis and display system for controlling the operation of the stage and optical system and for interpreting and storing the signals output by the detectors. The apparatus can operate in a die-to-die comparison mode or a die-to-database mode.

Abstract: A method and apparatus for inspecting patterned transmissive substrates, such as photomasks, for unwanted particles and features occurring on the transmissive, opaque portions and at the transition regions of the opaque and transmissive portions of the substrate. A transmissive substrate is illuminated by a laser through an optical system comprised of a laser scanning system, individual transmitted and reflected light collection optics and detectors collect and generate signals representative of the light transmitted and reflected by the substrate as the substrate is scanned repeatedly in one axis in a serpentine pattern by a laser beam which is focused on the patterned substrate surface. The defect identification of the substrate is performed using only those transmitted and reflected light signals, and other signals derived from them, such as the second derivative of each of them.

Abstract: An apparatus used to inspect patterned wafers and other substrates with periodic features for the presence of particles, defects and other aperiodic features in which a spatial filter placed in the Fourier plane is used in combination with either broadband illumination, angularly diverse illumination or both. In contrast to prior devices that direct light from a single monochromatic source through a pinhole aperture stop, embodiments are describes that illuminate a patterned substrate using (1) a single monochromatic source with a slit-shaped aperture stop for angularly diverse illumination, (2) a single broadband source with a pinhole aperture stop for broadband illumination, (3) a single broadband source with a slit-shaped aperture stop for both broadband and angularly diverse illumination, or (4) multiple sources with an aperture stop for each source for at least angularly diverse illumination.

Abstract: A broadband area-division beamsplitter that includes a pair of abutting triangular prisms providing two surfaces that are in optical contact in certain areas and are out of optical contact in other areas. One prism surface is substantially planar while adjoining surface of the other prism has alternating protrusions and depressions. The protrusions contact the substantially planar surface to form an optically continuous medium for light transmission. The depressions do not contact the planar surface forming gaps. The two surfaces are oriented on a diagonal so that light incident through one of the other prism faces is incident on the adjoining surfaces at an angle larger than the critical angle, providing total internal reflection at the out-of-contact gap regions. The protrusions and depressions on the one prism surface may be in the form of a corrugation or a checkerboard or some other patterns. The reticulation size of the pattern may be less than about 10 .mu.

Abstract: In each configuration, at least one TDI sensor is used to image substrate portions of interest, with those portions illuminated with substantially uniform illumination. In one configuration, a substrate is compared to prestored expected characteristic features. In a second configuration, first and second patterns in a region of the surface of at least one substrate are inspected by comparing one pattern against the other and noting whether they agree with each other. This is accomplished by illuminating the two patterns, imaging the first pattern and storing its characteristics in a temporary memory, then imaging the second pattern and comparing it to the stored characteristics from the temporary memory. Then the comparisons continue sequentially with the second pattern becoming the first pattern in the next imaging/comparison sequence against a new second pattern.

Abstract: In each configuration, at least one TDI sensor is used to image the portions of interest of the substrate that are substantially uniformly or critically illuminated. In one configuration, the substrate is compared to the expected characteristic features prestored in memory. In a second configuration, a first and second pattern in a region of at least one substrate are inspected by comparing one pattern against the other and noting whether they agree with each other. This is accomplished by illuminating the two patterns, imaging the first pattern and storing its characteristics in a temporary memory, then imaging the second pattern and comparing it to the stored characteristics from the temporary memory. Then the comparisons continue sequentially with the second pattern becoming the first pattern in the next imaging/comparison sequence against a new second pattern. With each comparison whether there has been agreement between the two patterns is noted.

Abstract: An end-viewed vapor discharge lamp having a differential temperature control structure that removes heat more effectively from a base end of the lamp than from the light emitting output end of the lamp. The lamp envelope which contains an excitable vapor, such as mercury, includes a small bore capillary tube with a window at one end. A large bore extension contiguous with the capillary tube and a parallel second tube contain electrodes for providing a discharge in the capillary tube. A thermally conductive shell surrounds and is spaced apart from sides of the envelope and is partly filled with a thermally conductive material around the base end of the envelope. The output end around the capillary tube is free of this material. Heat conduction is better at the base end so that the capillary tube runs hotter, inhibiting condensation of vapor and giving a stable light output. An optional heater pad may be provided around the shell for maintaining an optimal temperature for maximum light output.

Abstract: An end-viewed low-pressure gas discharge lamp and an envelope for said lamp having a capillary tube discharge bore for containing an excitable gas in which the capillary tube is in direct contact with a cooling medium. A window of optical quality fused silica, a thin section of bubble and particle free glass blown quality silica or sapphire is disposed on an end of the capillary tube for emitting light from a discharge of the excitable gas. A pair of electrodes are hermetically sealed through the envelope for producing a discharge in the capillary tube between the electrodes. The envelope may include a return path parallel to the capillary tube or a side tube as a means for connecting the two ends of the capillary tubes with the electrodes without obstructing the end view of the discharge. Filling the envelope with an excitable mixture of one or more gases, such as vaporized mercury, to a less than atmospheric pressure, and connecting the electrodes to a power supply completes the lamp.

Abstract: Substrate inspection apparatus and methods, and illumination apparatus. The inspection apparatus and method includes memory for storing the desired features of the surface of the substrate, focussed illuminator for substantially uniformly illuminating a region of the surface of the substrate to be inspected. Additionally there is a sensor for imaging the region of the substrate illuminated by the illuminator, and a comparator responsive to the memory and sensor for comparing the imaged region of the substrate with the stored desired features of the substrate. The illumination apparatus is designed to provide substantially uniform focussed illumination along a narrow linear region. This apparatus includes first, second and third reflectors elliptically cylindrical in shape, each with its long axis substantially parallel to the long axes of each of the others.

Abstract: An optical system simulates the optical effect of traveling over a large distance on light traveling from a first reference surface to a second reference surface. The first and second reference surfaces are relatively closely spaced. A first afocal magnifying lens system receives light from the first reference surface and provides a magnification ratio of M.sub.1. A second afocal magnifying lens system, spaced from the first afocal magnifying lens system by a predetermined distance D, receives light from the from the first afocal magnifying lens system and transmits it to the second reference surface with a magnification ratio of M.sub.2. The length of the distance which is simulated is related to the magnification ratio M.sub.1 of the first afocal magnifying lens system and to the predetermined distance D. The scale of the output image is related to magnification ratio M.sub.2.

Abstract: A confocal measuring microscope including a spectrometer and autofocus system sharing common optical elements in which the intensity of light entering the spectrometer from a particular spot on a workpiece is used to determine a focus condition for the same spot. The microscope includes at least one light source, an illumination field stop, and a microscope objective that images the stop onto a workpiece supported by a movable platform. The objective also forms an image of the illuminated portion of the object. An aperture in a second stop and intersecting the image plane passes light from part of the image to the spectrometer, while viewing optics are used to view the image. In one embodiment, a detector is placed at the zero order position, while in another embodiment a laser is placed at the zero order position. In the later embodiment an integrator circuit connected to the detector array replaces the zero order detector for measuring the total intensity of light entering the spectrometer.

Abstract: A gas discharge device containing at least two electrodes is shown, at least one thereof being insulated from the gas by a dielectric member containing a predetermined beneficial amount of a source of at least one Lanthanide Series rare earth including CeO.sub.2 or La.sub.2 O.sub.3. In one embodiment, a multiple gaseous discharge display/memory panel has an electrical memory and is capable of producing a visual display, the panel having an ionizable gaseous medium in a gas chamber formed by a pair of opposed dielectric charge storage members, each of which is backed by an array of electrodes that are oriented with respect to the array behind the opposing member to define a plurality of discrete discharge volumes constituting a discharge unit.

Abstract: There is disclosed a gas discharge device containing at least two electrodes, at least one of the electrodes being insulated from the gas by a dielectric member. There is particularly disclosed a multiple gaseous discharge display/memory panel having an electrical memory and capable of producing a visual display, the panel being characterized by an ionizable gaseous medium in a gas chamber formed by a pair of opposed dielectric material charge storage members, each of which is respectively backed by an array of electrodes, the electrodes behind each dielectric material member being oriented with respect to the electrodes behind the opposing dielectric material member so as to define a plurality of discrete discharge units.At least one dielectric insulating member contains a predetermined beneficial amount of a source of at least one element selected from P, As, Sb, or Bi.The selected element or elements may be utilized in any suitable form, such as a compound, mineral, and/or elemental.