Patents by Inventor Leendert Vriens

Leendert Vriens 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: 6559584
    Abstract: The CRT has a tensioned shadow mask with between 160-180 or between 210 and 240 slits per row and display devices having such CRT's. The first embodiment is in particular suited for CRT''s having a screen size larger than 21″ and for TVT applications, giving a substantially Moire free image for an NTSC, PAL and VGA signal, the second embodiment is in particular suited for CRT's having a screen size of 23″ or smaller and for CMT applications, giving a substantially Moire free image for a SVGA and XGA signal.
    Type: Grant
    Filed: March 19, 2001
    Date of Patent: May 6, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Leendert Vriens
  • Patent number: 6489712
    Abstract: A cathode ray tube having a tensioned shadow mask with elongated holes, i.e. holes with a length longer than 5 mm. The pattern of holes repeats itself after 5 or more rows and the relation between the number of rows after which the pattern repeats itself, the vertical pitch av and the horizontal pitch dh is given by av/dh≦n2≦8av/dh, most preferably n2≈2av/dh.
    Type: Grant
    Filed: October 31, 2000
    Date of Patent: December 3, 2002
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Leendert Vriens, Rudolf Maria Jozef Voncken, Daniƫl Den Engelsen
  • Publication number: 20010028210
    Abstract: The CRT has a tensioned shadow mask with between 160-180 or between 210 and 240 slits per row and display devices having such CRT's. The first embodiment is in particular suited for CRT''s having a screen size larger than 21″ and for TVT applications, giving a substantially Moire free image for an NTSC, PAL and VGA signal, the second embodiment is in particular suited for CRT's having a screen size of 23″ or smaller and for CMT applications, giving a substantially Moire free image for a SVGA and XGA signal.
    Type: Application
    Filed: March 19, 2001
    Publication date: October 11, 2001
    Inventor: Leendert Vriens
  • Patent number: 6239772
    Abstract: A display monitor operating under the raster scanning system repeats the line scanning of an electron beam by moving the resulting scanning lines in a direction substantially perpendicular to the line direction. In a cathode ray tube (CRT), the dot pitch of the fluorescent material on the display screen (DS) of the cathode ray tube (CRT) that can emit a fluorescence is determined by the aperture pitch of the shadow mask. Thus, in case of displaying a video pattern (f1h) in which consecutive pixels in a line repeat in an ON and OFF sequence an interference with the aperture pitch of the shadow mask may occur, thereby causing a moiré.
    Type: Grant
    Filed: February 17, 1998
    Date of Patent: May 29, 2001
    Assignee: U.S. Philips Corporation
    Inventors: Christaan Hentschel, Leendert Vriens
  • Patent number: 5841247
    Abstract: A display system which comprises a means for changing the s/a.sub.v and/or p/a.sub.h ratio, the scanning-line pitch s and/or the pixel pitch p of incoming signals.
    Type: Grant
    Filed: November 15, 1996
    Date of Patent: November 24, 1998
    Assignee: U.S. Philips Corporation
    Inventor: Leendert Vriens
  • Patent number: 5825435
    Abstract: By selecting the number of apertures per vertical row in the shadow mask of a color cathode ray tube to be in the range between 615 and 650, such a cathode ray tube can be used both in a PAL, an NTSC system and a MUSE system without the occurrence of disturbing Moire effects. In a second embodiment the number of apertures per row ranges between 425 and 450.
    Type: Grant
    Filed: August 31, 1995
    Date of Patent: October 20, 1998
    Assignee: U.S. Philips Corporation
    Inventors: Leendert Vriens, Rene A. Stoffels
  • Patent number: 5813753
    Abstract: A light emitting device for use in lighting and/or display applications includes a UV/blue LED located in a depression having reflecting sidewalls, a light transmitting material surrounding the LED and filling the depression, and a phosphor in the form of particles either dispersed in the light transmitting material or adhered to the surface of the LED. The sidewalls reflect UV as well as visible light, thus enhancing the efficiency of the device. Optical filters located on the top of the LED and/or the bottom of a UV absorbing glass plate covering the depression further enhance efficiency and/or spectral characteristics of the emitted light.
    Type: Grant
    Filed: May 27, 1997
    Date of Patent: September 29, 1998
    Assignee: Philips Electronics North America Corporation
    Inventors: Leendert Vriens, Gerard Acket, Cornelis Ronda
  • Patent number: 5813752
    Abstract: A visible light emitting device for use in lighting and/or display applications includes a UV LED, a phosphor layer on the upper, main light emitting surface of the LED, and a short wave pass (SWP) filter between the LED and the phosphor layer to transmit UV light from the LED to the phosphor layer, as well as to reflect visible light from the phosphor layer in a forward direction, thus enhancing the efficiency of the device. Additional optical filters located on the top of the phosphor layer further enhance efficiency and/or spectral characteristics of the emitted light.
    Type: Grant
    Filed: May 27, 1997
    Date of Patent: September 29, 1998
    Assignee: Philips Electronics North America Corporation
    Inventors: Barry Singer, Cornelis R. Ronda, Leendert Vriens
  • Patent number: 5698939
    Abstract: A display device having a cathode ray tube which comprises a display window. The radius of curvature of the inside of the display window along the diagonal (R.sub.diag) is greater than 1.6.times.1.767.times.D and smaller than 3.0.times.1.767.times.D, where D is the length of the diagonal of the display window. For the inside surface it holds that the quotient of the sagittal height at the end of the diagonal (21) and the sum of the sagittal heights at the end of the long axis (22) and at the end of the short axis (23) ranges between 0.75 and 0.95. In embodiments, the inside surface also complies with the formula 1.5<R.sub.x (0,0)/R.sub.x (x.sub.max, O)<4, where R.sub.x (0,0) and R.sub.x (x.sub.max, 0) are the radii of curvature along the long axis in the centre of the display window and at the end of the long axis, respectively. By virtue thereof, an improved picture display as regards reflection, local doming and raster distortion can be obtained.
    Type: Grant
    Filed: March 31, 1993
    Date of Patent: December 16, 1997
    Assignee: U.S. Philips Corporation
    Inventors: Leendert Vriens, Johannes C. A. Van Nes, Frank Gersmann
  • Patent number: 5619094
    Abstract: By selecting the number of apertures in the shadow mask of a color cathode ray tube system to be such that the s/a.sub.v ratio, where s is the scan pitch for the entire frame and a.sub.v is the vertical mask pitch, is between 5.8/8 and 6.4/8 (5.8/8.ltoreq.s/a.sub.v .ltoreq.6.4/8) or between 9.4/8 and 10.6/8 where the lines are progressively scanned or, where the lines are scanned in an interlace mode with a frequency higher than 70 Hz, the s/a.sub.v ratio is between 5.8/8 and 6.4/8 (5.8/8.ltoreq.s/a.sub.v .ltoreq.6.4/8) or between 9.4/8 and 10.6/8, a cathode ray tube system is provided with a reduced occurence of disturbing Moire effects.
    Type: Grant
    Filed: September 26, 1995
    Date of Patent: April 8, 1997
    Assignee: U.S. Philips Corporation
    Inventor: Leendert Vriens
  • Patent number: 5319280
    Abstract: A display device having a rectangular display window with a major and a minor dimension, and a deflection unit producing a scanning line raster on a display screen on the inner surface of the display window, the scan lines extending in the minor direction. The inside surface of the display window has a major radius of curvature (R.sub.cmajor), a minor radius of curvature (R.sub.cminor), a diagonal dimension (D) and an aspect ration (A), which parameters are related by the formulas 1.1<R.sub.cminor /D<2.5, also 2.5<R.sub.cmajor /D, also R.sub.cmajor >A*R.sub.cminor. The display window is thereby very flat and scanning line raster distortion is reduced so that it is easily correctible by the deflection fields produced by the deflection unit.
    Type: Grant
    Filed: April 9, 1992
    Date of Patent: June 7, 1994
    Assignee: U.S. Philips Corporation
    Inventor: Leendert Vriens
  • Patent number: 5209690
    Abstract: Method of vapor-depositing an interference filter layer on the inside of a display window, a display window, a projection cathode ray tube and a projection television apparatus.A method of manufacturing a projection cathode ray tube comprising an interference filter on an inwardly directed surface of a display window, the method comprising as a process step the vapor deposition of at least one layer of the interference filter. It has been found that the edges of a display window during the vapor deposition of an interference filter layer detrimentally influence the thickness of the vapor deposited layer, the thickness increases more towards the edges than follows from geometrical computations. In the method according to the invention vapor deposition is performed on a display window for which the height of the edge is less than 1/5 of the minor axis. The display screen preferably comprises a recessive edge.
    Type: Grant
    Filed: July 20, 1992
    Date of Patent: May 11, 1993
    Assignee: U.S. Philips Corporation
    Inventors: Leendert Vriens, Andre van der Voort, Antonius P. van de Langenberg
  • Patent number: 5179312
    Abstract: Device for projecting television pictures by means of an assembly of three television picture tubes with associated lens systems arranged in each other's proximity, including an integrated cooling system. The integrated cooling system has a liquid circuit comprising a first duct extending below the television picture tubes, which duct is in direct communication via passages with the lower ends of the flow spaces, and a second duct extending above the television picture tubes, which duct is in direct communication via passages with the upper ends of the flow spaces. The first and the second duct are connected via at least one connection duct which extends along an end the assembly constituted by the three television picture tubes.
    Type: Grant
    Filed: May 5, 1986
    Date of Patent: January 12, 1993
    Assignee: U.S. Philips Corporation
    Inventors: Leendert Vriens, Gerrit B. Gerritsen
  • Patent number: 5168351
    Abstract: A video color image projector which includes a block of crossed dichroic mirrors for combining the light rays from image rasters on respective monochrome image display devices and a projection lens for projecting the composite color rays so as to form an enlarged color image on a display screen. Each display device has a faceplace which is convex on the interior surface thereof and having thereon an interference filter in the form of an internal angularly reflecting coating (IARC). Each faceplate is liquid - coupled to a negative power lens element, so that the faceplate, coupling liquid (or gel) and such lens element effectively constitute a single negative power field flattener lens at each entrance side of the dichroic block. The composite color rays at the exit side of the dichroic block are projected on the display screen by an assembly of lens elements which includes at least one optically positive lens element.
    Type: Grant
    Filed: May 16, 1990
    Date of Patent: December 1, 1992
    Assignee: North American Philips Corporation
    Inventors: Ralph H. Bradley, Leendert Vriens, William F. Guerinot, Jill F. Goldenberg
  • Patent number: 5099169
    Abstract: Picture display device comprising an in-line color display tube of the shadow mask type having an elongate display screen with a short axis and a long axis, and comprising a deflection system. The plane in which the undeflected electron beams are located is parallel to the short axis of the display screen. The shadow mask has elongate apertures with longitudinal axes extending transversely to the short axis of the display screen. This configuration renders the picture display device less sensitive to unwanted displacements of the shadow mask in the direction transverse to the display screen, which is advantageous, particularly for display screen aspect ratios of more than 4:3.
    Type: Grant
    Filed: April 6, 1990
    Date of Patent: March 24, 1992
    Assignee: U.S. Philips Corporation
    Inventor: Leendert Vriens
  • Patent number: 5068568
    Abstract: A cathode ray tube, such as a projection cathode ray tube, having a multilayer interference filter disposed between the cathodoluminescent screen and the interior side of the faceplate, the interference filter comprising alternate layers having high (H) and low (L) refractive indices, the high refractive index material being niobium pentoxide and the low refractive index material being either silicon oxide or magnesium fluoride. These filters are substantially free from the crazing which occurs in known filters when subjected to the normal thermal processing of cathode ray tubes.
    Type: Grant
    Filed: May 15, 1990
    Date of Patent: November 26, 1991
    Assignee: U.S. Philips Corporation
    Inventors: Henricus M. de Vrieze, Johannes H. J. Roosen, Leendert Vriens
  • Patent number: 5061993
    Abstract: Projection television display device includes three monochrome projection television display tubes (20, 21, 22) each having a display screen (24, 25, 26) which is provided on the inside of the display window (23) and luminesces in a different color. Each tube has an optical axis extending perpendicularly from the center of the display screen, the optical axes (33, 34, 35) of the three display screens being co-planar. The axes (34, 33) of the display screens of the first and second tubes (20, 22) coincide and the axis (35) of the display window of the third tube (21) constitutes the main axis of the device, the axis being perpendicular to the two coincident axes (33, 34). Two flat dichroic intersecting reflective mirrors (27, 29) extend perpendicularly of the plane and through the point of intersection of the axes, each at an angle of 45.degree. with the main axis.
    Type: Grant
    Filed: November 14, 1988
    Date of Patent: October 29, 1991
    Assignee: U.S. Philips Corporation
    Inventors: Leendert Vriens, Johannes H. M. Spruit, Johannes C. N. Rijpers
  • Patent number: 4990824
    Abstract: A color cathode ray tube of the shadow mask or beam index type in which the screen structure applied to the faceplate has a plurality of triplets of optical interference filter stripes which are adapted to pass red (R), green (G) and blue (B) light produced by a homogeneous cathodoluminescent screen layer. The usual aluminium layer may be applied to the screen layer. The optical interference filter stripes may have short wave pass filters, band pass filters or a combination of both types. The short wave pass filter stripes may have modified quarter wavelength multilayer dielectric filters and the bandpass filter may have a Fabry-Perot filter.
    Type: Grant
    Filed: March 31, 1988
    Date of Patent: February 5, 1991
    Assignee: U.S. Philips Corporation
    Inventors: Leendert Vriens, Johannes C. N. Rijpers, Albert A. Comberg, Johannes H. M. Wilting, Aart A. Van Gorkum, Franciscus A. Vollenbroek
  • Patent number: 4988203
    Abstract: In a device for measuring the cut-off wavelength of an interference filter for a projection television display tube, the interference filter and a bandpass filter are arranged one behind the other. The bandpass filter has a transmission characteristic with a cut-off wavelength which approximately coincides with the desired cut-off wavelength of the interference filter, but with a slope varying in the opposite direction. A white light beam generated in a light source is incident through the two filters. The intensity, which is measured by a detector on the other side of the filters, is a measure of the cut-off wavelength of the interference filter. The device may have a second measuring system for measuring the absorption of the interference filter.
    Type: Grant
    Filed: March 28, 1989
    Date of Patent: January 29, 1991
    Assignee: U.S. Philips Corporation
    Inventors: Leendert Vriens, Maurits R. T. Smits
  • Patent number: RE34131
    Abstract: A projection television system comprising an array of three projection television display tubes (14) luminescing in red, green and blue, a focusing lens (16) associated with each tube and a display screen (12) on which the respective optical images are merged to form a single multicolored image. At least one of the display tubes (14) has a multilayer interference filter (46) between the phosphor (30) and the faceplate (20). In order to imprve the light output at the corners of the display screen (12), the cut-off angle of the first filter layers is varied between the center and the corners thereof, for example by increasing the optical thickness of the filter layers relative to the center.
    Type: Grant
    Filed: January 9, 1991
    Date of Patent: November 24, 1992
    Assignee: U.S. Philips Corporation
    Inventors: Leendert Vriens, Johannes H. M. Spruit, John A. Clarke