Patents by Inventor Joseph Shmulovich

Joseph Shmulovich 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: 4894583
    Abstract: Certain yttrium orthosillicate phosphors doped with various rare-earths are particularly suitable for use in various display devices including cathode ray tubes. Included are single crystal phosphors which exhibit high brightness and long life under high energy excitation and conventional powder phosphors with great sensitivity.
    Type: Grant
    Filed: September 2, 1988
    Date of Patent: January 16, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: George W. Berkstresser, Charles D. Brandle, Jr., Joseph Shmulovich, Alejandro J. Valentino
  • Patent number: 4807241
    Abstract: The luminescent screen of a cathode ray tube includes an array of monocrystalline or amorphous phosphor rod-like elements which are covered with a reflective coating except for one end of each element which serves as an output face. The phenomenon of the light trapping is advantageously exploited to achieve enhanced brightness. The screen is illuminated with an electron beam which has an essentially oblong cross section and which is oriented along the elongated dimension of the elements. In one embodiment the elements comprise epitaxial Lu.sub.3 Al.sub.3 Ga.sub.2 O.sub.12 :Ce on the top of a YAG substrate, and a light absorbing layer of Lu.sub.3 Al.sub.3.5 Fe.sub.1.5 O.sub.12 is formed on the bottom of the substrate. A printer utilizing such a CRT is described. Also described is a configuration in which each of the rod-like elements functions as a laser.
    Type: Grant
    Filed: July 10, 1987
    Date of Patent: February 21, 1989
    Assignee: American Telephone and Telegraph Company AT&T Bell Laboratories
    Inventors: George W. Berkstresser, Joseph Shmulovich
  • Patent number: 4757232
    Abstract: A novel epitaxial phosphor having high luminosity at about 540 nm has the composition (Y.sub.3-x-y Tb.sub.x RE.sub.y)(Al.sub.5-w Ga.sub.w)O.sub.12, with RE being one (or more) 4f-type rare earth(s) other than Tb, 0.09<x<0.7, and 1.5<w<2.5. In preferred embodiments, RE is Lu, Yb, or Tm, 0.1<x<0.3, and 1.8<w<2.2. In further preferred embodiments, the phosphor composition is adjusted to yield a material having a lattice constant within 0.002 nm of the lattice constant of the substrate, typically Y.sub.3 Al.sub.5 O.sub.12. The phosphor is typically grown by liquid phase epitaxy and has application in a variety of apparatus, including avionic displays and flight simulators.
    Type: Grant
    Filed: January 16, 1985
    Date of Patent: July 12, 1988
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: George W. Berkstresser, Tai-Chan D. Huo, Joseph Shmulovich
  • Patent number: 4755715
    Abstract: A phosphor for use in CRTs comprises (Y.sub.3-p-m-n R.sub.p Pr.sub.m Tb.sub.n)(Al.sub.5-q Z.sub.q)O.sub.12, where R is a lanthanide element and Z is a Group III element. One embodiment described is a single crystal of (Y.sub.3-m-n Pr.sub.m Tb.sub.n)Al.sub.5 O.sub.12 in which the trivalent Pr and Tb activators exhibit co-emission and the phosphor emits white light.
    Type: Grant
    Filed: February 28, 1986
    Date of Patent: July 5, 1988
    Assignee: American Telephone & Telegraph Company, AT&T Bell Laboratories
    Inventors: George W. Berkstresser, Joseph Shmulovich
  • Patent number: 4695762
    Abstract: The luminescent screen of a cathode ray tube includes an array of monocrystalline or amorphous phosphor rod-like elements which are covered with a reflective coating except for one end of each element which serves as an output face. The phenomenon of the light trapping is advantageously exploited to achieve enhanced brightness. The screen is illuminated with an electron beam which has an essentially oblong cross section and which is oriented along the elongated dimension of the elements. In one embodiment the elements comprise epitaxial Lu.sub.3 Al.sub.3 Ga.sub.2 O.sub.12 :Ce on the top of a YAG substrate, and a light absorbing layer of Lu.sub.3 Al.sub.3.5 Fe.sub.1.5 O.sub.12 is formed on the bottom of the substrate. A printer utilizing such a CRT is described. Also described is a configuration in which each of the rod-like elements functions as a laser.
    Type: Grant
    Filed: June 28, 1985
    Date of Patent: September 22, 1987
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: George W. Berkstresser, Joseph Shmulovich
  • Patent number: 4626739
    Abstract: In a CRT system the luminescent screen includes an ordered array of rows and columns of phosphor elements, illustratively made of single crystal material. Each element is surrounded on all sides (except the light output face) by reflective material. To enhance light extraction efficiency, the output face may be textured. An electron beam is made incident on the output face of selected ones of the elements and scans in two dimensions across the plane of the elements. Also described is an arrangement whereby the electron beam is made incident on the back surface of the elements opposite the output face.
    Type: Grant
    Filed: May 10, 1984
    Date of Patent: December 2, 1986
    Assignee: AT&T Bell Laboratories
    Inventor: Joseph Shmulovich
  • Patent number: 4550256
    Abstract: The disclosed display apparatus comprises a novel high intensity broadband-emitting phosphor. The phosphor is single crystal material in which Tb acts as sensitizer of Ce, the activator. The composition of the phosphor is (Y.sub.3-x-y-z Ce.sub.x Tb.sub.y RE.sub.z) Al.sub.5-w X.sub.w O.sub.12, where RE is one or more 4f-type rare earths other than Y, Ce, and Tb, X is Sc, Ga, or In, and 0<x.ltoreq.0.06, 0<y.ltoreq.0.5, 0.ltoreq.z.ltoreq.2, 0.ltoreq.w.ltoreq.3. In preferred embodiments z and w are either zero, or RE is Lu and X is Ga. The phosphor is typically grown epitaxially by LPE on a Y.sub.3 Al.sub.5 O.sub.12 substrate, and has application in a variety of apparatus, including aircraft cockpit head-up displays and flight simulators.
    Type: Grant
    Filed: October 17, 1983
    Date of Patent: October 29, 1985
    Assignee: AT&T Bell Laboratories
    Inventors: George W. Berkstresser, Tai-Chan D. Huo, Joseph Shmulovich