Abstract: An interferometric system for testing a lens comprises a source of light and a beam splitter in the path of the light divides the light into first and second beams. A device is provided for holding the lens to be tested in the first beam. A reflector is disposed in the path of the first beam beyond the lens for reflecting the first beam to the beam splitter. A movable reflector is provided in the path of the second beam for reflecting the second beam to the beam splitter to form a single recombined beam. The movable reflector is displaceable in translation along the axis of the beam it reflects and in rotation about an axis or orthogonal axes in the plane of the movable reflector and perpendicular to the beam axis. The entire recombined beam impinges on a photoelectric detector which, in response thereto, generates an electrical signal representing the complex point spread function of the lens being tested.

Abstract: A flowmeter system for measuring the flow and changes in the velocity of sound due to changes in composition or temperature of a fluid medium in a flow tube including transducers which generate acoustic compression waves in the fluid medium, phase lock loop transmitter/receiver circuitry including device for measuring the difference in phase of the acoustic compression waves transmitted upstream relative to that received and for measuring the phase difference of the acoustic compression waves transmitted downstream relative to that received and producing a sum signal dependent upon the sum of the two measured phase differences, device for producing a difference signal proportional to the difference of the two measured phase differences which provides an output signal representing the direction and magnitude of the measured flow device for automatically adjusting the frequency of the acoustic compression waves so that their wave lengths remains constant, said means for automatically adjusting the frequency inc

Abstract: An automatic focusing system for positioning silicon or other wafer within the focal plane of a photolithographic mask projection system. The position of the wafer is measured at a plurality of points and compared to the position of an optical flat located in the focal plane to provide signals for positioning the wafer at the focal plane of the projection system. The system also includes means for changing the contours of the wafer to cause it to lie in a known plane.

Abstract: The first element comprises a relatively thin transmissive shell concave toward the front. The second element comprises a mirror concave toward the front. The front surface of the shell may be spherical, and the rear surface aspheric, or vice versa. The central portion of the first element on either the front or back surface is mirrored to form the secondary of the system. Preferably the secondary mirror is on the front of the first element. In one embodiment the second element is also a transmissive shell. In one form of this embodiment the second transmissive shell is aspheric on the front and spherical on the back. In another form it is spherical on the front and aspheric on the back. In both of these forms the primary mirror is located on the back of the second element. In another embodiment the second transmissive element is aspheric on the front and flat on the back; the front surface being mirrored except for the central portion thereof, through which light from the secondary is focused.

Abstract: In order to obtain shorter exposure time and to obtain a longer life in x-ray lithography apparatus, an x-ray target made of tungsten is utilized and the apparatus operated to generate the tungsten M-line, this line being at a wavelength which will be absorbed by the resist normally used in lithography. To develop the resist, which was initially designed for use in an electron beam lithography, a developing method is used in which a initial short development with a high concentration is first carried out followed by a longer, full development with a concentration which is approximately the lowest at which complete development will take place.

Abstract: An apparatus for etching one wafer while simultaneously pretreating or stripping another wafer. A module comprises a wafer etching chamber disposed within a larger chamber. The wafer etching chamber is adapted to etch a first wafer during the time that a second wafer is being pretreated in the larger chamber. When the first wafer is etched, it is transferred to the larger chamber and the pretreated second wafer is transferred to the etching chamber. During the time the second wafer is being etched the first wafer is stripped and removed from the larger chamber. A third wafer is introduced into the larger chamber for pretreating while the second wafer is being etched and the process repeated. Once a wafer enters the module for pretreating, etching and stripping, it is not exposed to the atmosphere until stripping is complete.

Abstract: An article of manufacture and a method for manufacturing a mercury vapor lamp wherein a glass mounting base is formed separately and fixed by fusing it to one end of a tubular glass envelope. The glass envelope has an evacuated bore of capillary dimension which is precisely positioned relative to the glass base and in which conductive wires are fixed at each end during the fusing process.

Abstract: A field emission gun, for either electron or positive ion emission, in which the beam current between source and sample is measured at accelerating voltage potential between two concentric shields that enclose the gun, its power supplies, and the measuring circuitry. The outer shield is directly connected to the high voltage terminal of the accelerating voltage supply while the inner shield is at the local ground reference of the emission source and associated components. The current between the concentric shields is measured, converted to a proportional voltage signal, compared with the reference voltage, and applied to a field strength controlling electrode in the vicinity of the emission source to modulate the emission and to maintain a constant beam current.

Abstract: There are disclosed method and apparatus for precisely aligning the pattern of an opaque mask with a previously exposed pattern on a silicon wafer. Three separate optical channels are aligned so that their axes coincide with three targets on the wafer. The objectives are also adjusted to the same vertical distance from the wafer. Thereafter, the optical channels remain fixed. The wafer is retracted a short distance and is replaced by the mask which also has three targets. The mask is then shifted to align the targets with the prealigned optical axes. When mask alignment is completed, the mask and the wafer are removed as a unit to an exposure station.

Abstract: The systems comprise a transmissive shell and a mirror. The surfaces of the shell and the mirror are monocentric; that is, spherical and have the same center of curvature. Both the object and image planes are located in front of and spaced away from the transmissive shell.Single optical element systems comprise a transmissive shell with the mirror and the back surface of the shell being coincidence. These elements may be used as laser beam focusers, beam divergers and collimators.Unit relay systems for use in super accurate microcircuit printing are disclosed. Parameters are given for a monochromatic diffraction limited f/2 system in the ultraviolet.A single element monocentric catadiotric system is disclosed, which is corrected for 3rd and 5th order spherical aberration and all field aberrations except Petzval curvature. A two-element version can cover very wide fields of view with good performance at speeds as fast as f/0.6.

Abstract: A shredder includes a pair of blade assemblies operated at high speeds to receive and shred paper material, such as notes or coupons. The blades of the assemblies are disposed to contact and overlap each other. Means are provided to control the amount of overlap and loading of the blades.

Abstract: A method of depositing X-ray absorber patterns on a mask membrane to achieve minimum pattern feature dimensions less than 1 .mu.m. The membrane is covered with an ultraviolet (VU) sensitive photoresist which carries a thin metallic film. The metallic film is coated with an electron beam resist. The electron beam resist is exposed to the desired pattern by an electron beam. After development, the metal film is etched through the remaining electron beam resist. This forms a stencil overlying the lower UV photoresist layer which is then exposed by an ultraviolet or soft X-ray source. After development, an X-ray absorber, such as gold, is deposited on the membrane. The final exposure step may be done by means of a point source of radiation. The X-ray absorbers will then have sloping walls to prevent shadowing of the X-ray source.

Abstract: A rotatable drum switches a vacuum source on and off towards an outermost bill in a stack to separate bills one at a time at high speeds from the stack and provide registration between the separate bills. As the bills are separated from the stack, means are provided to maintain a relatively constant pressure on the stack of bills. Flexible bands transport the separated bills away from the stack.

Abstract: An apparatus for transferring a portion of an image from the spherical focal surface of a telescope to a fixed viewing area. A spherical parallelogram type linkage has means for selectively positioning a mirror in the spherical focal surface of the telescope and constrains the mirror to move within the contour of the spherical focal surface of the telescope. The parallelogram type linkage includes means for transferring the image reflected by the mirror to a remote viewing area.

Abstract: Apparatus for detecting and/or determining the wavelength of coherent radiation in the presence of incoherent ambient radiation. The apparatus includes at least three unequal path interferometers with the radiation path length difference in each interferometer being substantially greater than the coherence length of the incoherent radiation, but substantially less than the coherence length of the coherent radiation, the average radiation path length in said three interferometers being different one from the others. The apparatus further includes detectors for detecting the radiation transmitted through each of the interferometers for generating signals corresponding to the radiation leaving each interferometer, and electronic processing elements to detect and determine the wavelength of the coherent radiation.A preferred form of interferometer is a Fabry-Perot etalon having a plurality of regions of different thicknesses.

Abstract: An apparatus and method for coating a substrate. An electrically conductive substrate is placed in an electrolytic bath with the surface to be coated facing the anode. The cathode is placed near but not touching the other side of the substrate and an electric potential is applied to both electrodes. Means are provided to prevent electroplating of the cathode.

Abstract: Circuitry for recording and subsequently reading magnetic tape recorded binary data without tape flutter. The circuitry includes time base correction circuitry to assure a precise crystal controlled data output and a precise long-term data output speed to thereby assure against loss of data being transmitted from the system during a fixed time frame.

Abstract: In order to make a mask for use in lithography a layer of reflective material is first deposited on a substrate which is transparent to the radiation with which the mask is to be used; a layer of photoresist then deposited; the photoresist exposed with the desired pattern by UV radiation; the photoresist developed to expose the reflective material in the areas where it is desired to deposit an absorber material; the reflective material etched away from these areas undercutting the resist; the absorber deposited through the openings in the resist and reflective layer and the resist then lifted off.

Abstract: An apparatus and method for coating a substrate with a thin film of material. The coating material is converted to a mist by means of an ultrasonic nebulizer and transported by a carrier gas to a chamber which contains the substrate where the mist is allowed to settle onto the substrate under the force of gravity. Sonic means are also provided to increase the settling rate of the mist droplets to lessen the settling time. Means are also provided to maintain the volume and concentration of the coating material in the nebulizer chamber over successive coatings.

Abstract: An optical system for insertion into projection apparatus to permit viewing an image projected on an image plane without affecting its quality, size or position, including a beam-splitting element disposed in the optical path before the image plane which will transmit the radiation to the image plane and reflect a portion of the radiation reflected from the image plane in a direction which permits viewing, optical elements disposed in the optical path to correct for image displacement and aberrations caused by the beam-splitting element, said optical system being of unit power; according to one aspect of the invention the system is afocal so that it will remain at unit power when it is shifted longitudinally and the image position is insensitive to longitudinal displacement; and according to another aspect of the invention each element of the system is afocal so that the system remains at unit power and insensitive to changes in spacing between the elements.