Patents by Inventor Thomas E. Parker

Thomas E. Parker has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5594979
    Abstract: A pair of crystallographically matched piezoelectric substrates are sealed together to provide a package for a SAW device. A sealant material including a glass frit is deposited on a selected portion of a first one of the pair of substrates. The substrate having the sealant material is then heated to a temperature which is substantially below the glazing temperature of the sealant material to dry the sealant material. The substrate having the dried sealant material is heated a second time at a temperature just above the softening temperature of the glass frit to glaze the glass frit component with other components of the sealant material being driven from the glass frit during the heating cycles. The substrate having the glazed frit and the other remaining substrate are then mated together in a predetermined manner.
    Type: Grant
    Filed: September 13, 1984
    Date of Patent: January 21, 1997
    Assignee: Raytheon Company
    Inventors: Earl F. Borchelt, Thomas E. Parker
  • Patent number: 5416447
    Abstract: A SAW oscillator circuit including a housing having disposed therein a surface wave propagation supporting substrate with a pair of transducers coupled by surface waves propagating through the substrate and electronic circuitry connected to the pair of transducers and arranged to provide, with the connected resonator, the SAW oscillator circuit. A weight is attached to the resonator. The housing is susceptible of vibratory deflections which induce vibratory deflections in the substrate and the weight suppresses the vibratory deflections induced in the substrate of the resonator. With such arrangement, while sufficiently thick externally mounted stiffeners are not used because of space limitations, the effects of vibratory deflections induced in the substrate of the insufficiently thick, or un-stiffened housing are compensated by the weight attached to the resonator.
    Type: Grant
    Filed: November 8, 1993
    Date of Patent: May 16, 1995
    Assignee: Raytheon Company
    Inventors: Donald Andres, Thomas E. Parker
  • Patent number: 5345201
    Abstract: A low vibration sensitive SAW device includes a first quartz substrate having a pair of opposing surfaces, each surface which supports surface wave propagation. A pair of transducers are coupled to each of said surface wave propagation surfaces providing a pair of surface wave devices on opposing surfaces of the substrate. Each surface wave propagating surface is covered by a matching quartz cover and a glass-frit seal to provide a three piece all-quartz package. The pair of devices are connected together in parallel generally externally from the package, and when the dual device package undergoes vibration in a direction perpendicular to the surface wave propagation surfaces, one surface of the substrate will be subjected to a tensile strain field, whereas the opposite surface of the substrate will be subjected to identical but opposite direction strain field that is compressive.
    Type: Grant
    Filed: June 29, 1988
    Date of Patent: September 6, 1994
    Assignee: Raytheon Company
    Inventors: James A. Greer, Thomas E. Parker
  • Patent number: 5337026
    Abstract: A pair of crystallographically matched piezoelectric substrates are sealed together to provide a package for a SAW device. A sealant material including a glass frit is deposited on a selected portion of a first one of the pair of substrates. The substrate having the sealant material is then heated to a temperature which is substantially below the glazing temperature of the sealant material to dry the sealant material. The substrate having the dried sealant material is heated a second time at a temperature just above the softening temperature of the glass frit to glaze the glass frit component with other components of the sealant material being driven from the glass frit during the heating cycles. The substrate having the glazed frit and the other remaining substrate are then mated together in a predetermined manner.
    Type: Grant
    Filed: April 26, 1985
    Date of Patent: August 9, 1994
    Assignee: Raytheon Company
    Inventors: Earl F. Borchelt, Thomas E. Parker
  • Patent number: 5208504
    Abstract: A SAW oscillator package having low vibration sensitivity includes a stiffener layer disposed between a mounting surface for the oscillator and the oscillator circuit package. Preferably, the stiffening layer comprises a slab of a highly stiff material such as a ceramic and, in particular, aluminum oxide, as well as other material which preferably have suitable thermal expansion coefficients matched between the material of the package and the mounting surface. Moreover, the rigidly of the SAW device itself is also increased by either reducing the lateral dimensions of the SAW device or increasing the thickness of the SAW substrate and/or cover.
    Type: Grant
    Filed: December 28, 1990
    Date of Patent: May 4, 1993
    Assignee: Raytheon Company
    Inventors: Thomas E. Parker, James A. Greer
  • Patent number: 5039957
    Abstract: A surface acoustic wave device having interdigitated transducers comprised of an improved metalization system including copper and titanium doped aluminum transducers. A method of producing the interdigitated transducers includes deposition of the metals on a quartz substrate and subsequent heat treatment. The metalization system provides SAW devices having improved long-term frequency stability, particularly when operated at high power levels. The surface acoustic wave device may be incorporated in a feedback loop of an amplifier to form an oscillator circuit.
    Type: Grant
    Filed: May 7, 1990
    Date of Patent: August 13, 1991
    Assignee: Raytheon Company
    Inventors: James A. Greer, Thomas E. Parker, Gary K. Montress
  • Patent number: 4270105
    Abstract: A surface acoustic wave (SAW) device is provided with short-term and long-term stability by recessing the electrode structure into the surface of the piezoelectric crystal of the device. In addition, the surface is passivated with the silicon polymer, and a cover of the same crystalline material is placed above the electrode structure to prevent absorption of impurities into the surface from the atmosphere. The passivation is believed to reduce the effect of thermal agitation of the bonds of the crystal lattice structure, and thereby prevent the making and breaking of chemical bonds with hydroxyl ions that may have been entrapped from the atmosphere. The SAW device is particularly useful in the construction of stable oscillator circuits wherein the passivation provides improved short-term frequency stability and the cover provides long-term frequency stability.
    Type: Grant
    Filed: May 14, 1979
    Date of Patent: May 26, 1981
    Assignee: Raytheon Company
    Inventors: Thomas E. Parker, Clarence J. Dunnrowicz
  • Patent number: 3965444
    Abstract: A temperature compensated surface acoustic wave device having an SiO.sub.2 film layer upon a substrate of piezoelectric material. The positive temperature coefficient of delay of the piezoelectric substrate is counterbalanced by the negative temperature coefficient of the SiO.sub.2 layer. The thickness and shape of the SiO.sub.2 layer are chosen to give a zero first order temperature coefficient for the composite device. Lithium niobate and lithium tantalate are preferred piezoelectric materials for the substrate. A high degree of temperature stability is thereby obtained with coupling coefficients much greater than were previously obtained by prior temperature compensated surface acoustic wave devices.
    Type: Grant
    Filed: January 3, 1975
    Date of Patent: June 22, 1976
    Assignee: Raytheon Company
    Inventors: Charles B. Willingham, Thomas E. Parker, Frank H. Spooner