Patents by Inventor Leo F. Johnson

Leo F. Johnson 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: 5488624
    Abstract: An upconversion laser system that uses solid state components throughout and achieves such operation with a substantially coherent, continuous or quasi-continuous single band infrared pumping source using successive energy transfers between the sensitizer and activator in the host of the lasant upconversion material.
    Type: Grant
    Filed: February 8, 1994
    Date of Patent: January 30, 1996
    Assignee: Amoco Corporation
    Inventors: Robert J. Thrash, Leo F. Johnson
  • Patent number: 5299215
    Abstract: An upconversion laser system that uses solid state components throughout and achieves such operation with a continuous or quasi-continuous single band infrared pumping source using successive energy transfers between the sensitizer and activator in the host of the lasant upconversion material.
    Type: Grant
    Filed: September 25, 1991
    Date of Patent: March 29, 1994
    Assignee: Amoco Corporation
    Inventors: Robert J. Thrash, Leo F. Johnson
  • Patent number: 4460434
    Abstract: A method of planarizing a surface using ion beam milling at a non-normal angle of incidence that is useful in semiconductor device manufacture is described.
    Type: Grant
    Filed: April 26, 1983
    Date of Patent: July 17, 1984
    Assignee: AT&T Bell Laboratories
    Inventors: Leo F. Johnson, Dawon Kahng
  • Patent number: 4372641
    Abstract: Optical communications networks may be implemented by means of a patterned layer of an optically transparent material on a substrate. Where an optical path terminates, e.g., at an on-off switch, it is desirable to optically terminate a waveguide so as to minimize spurious signals due to reflection.The invention provides for optical termination of a waveguide by essentially complete absorption of light. Absorption is effected in a portion of the waveguide which comprises light absorbing centers such as, e.g., carbon or metal particles, anions, cations, or molecules which absorb light at desired wavelengths. Absorbing centers may be comprised in a central portion of a waveguide or, more conveniently, in a portion adjacent to a central portion.
    Type: Grant
    Filed: June 27, 1980
    Date of Patent: February 8, 1983
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Leo F. Johnson, LeGrand G. Van Uitert
  • Patent number: 4321282
    Abstract: A method is described for increasing the spatial frequency of surface relief structures. Periods as small as 750 Angstroms have been made.
    Type: Grant
    Filed: February 6, 1981
    Date of Patent: March 23, 1982
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: Leo F. Johnson
  • Patent number: 4245883
    Abstract: Electrically activated components such as switches, modulators, attenuators, and mode selectors are disclosed which can be used in networks of waveguides in optical communications systems. Disclosed components comprise an electrochromic medium in combination with a suitable ion source and means for producing a variable electric field across the medium. A change of color in the medium in response to variation of the electric field strength is instrumental in influencing direction and intensity of light propagating in a network.
    Type: Grant
    Filed: December 26, 1978
    Date of Patent: January 20, 1981
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Leo F. Johnson, Shobha Singh, LeGrand G. Van Uitert
  • Patent number: 4241109
    Abstract: An oblique shadow deposition technique for altering the profile of grating relief patterns on surfaces is described. In one aspect the technique essentially represents a method whereby a series of grating masks may be superimposed in precise registration with each other. By appropriate choice of deposition angle, deep grooves may be generated from shallow profiles, rounded or sinusoidal profiles may be transformed to structures with planar vertical walls, and symmetric profiles may be made asymmetric.
    Type: Grant
    Filed: April 30, 1979
    Date of Patent: December 23, 1980
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: Leo F. Johnson
  • Patent number: 4240693
    Abstract: Electrically activated optical switches, couplers, and modulators are disclosed which can be incorporated in waveguide networks in optical communications systems. Disclosed devices comprise an electroplating medium in combination with a suitable source of an electric field whose strength can be varied to cause transition of the electroplating medium between plated and unplated states. Changes of reflectivity and refractive index are the bases of switching and coupling applications, respectively.
    Type: Grant
    Filed: December 26, 1978
    Date of Patent: December 23, 1980
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Leo F. Johnson, Shobha Singh, LeGrand G. Van Uitert