Back to results
US 7,993,047 B2Granted
Direct type backlight unit
AssigneeLG Display Co., Ltd.
InventorDae San Lim
Life of this patent
Estimating the term…
Abstract
A backlight unit is disclosed which improves picture quality by preventing a bright line or a dark line from being visible in the center of the display area. The backlight unit includes a plurality of U-shaped lamps arranged in two columns, wherein curved portions of the two opposite U-shaped lamps are symmetrically positioned in the center of a display area. Each of the curved portions of the U-shaped lamps has a non-luminous part so that light is not emitted by the curved portions of the U-shaped lamps. Optical sheets are provided above the U-shaped lamps, and a reflective sheet is provided below the U-shaped lamps.
Claims6
A direct type backlight unit comprising:
- a plurality of U-shaped lamps arranged in two columns, wherein curved portions of two opposite U-shaped lamps are symmetrically positioned in the center of a display area, and the curved portion of any one of the two U-shaped lamps has a non-luminous portion, so as to provide a uniform luminance across the plurality of U-shaped lamps,
- wherein a fluorescent substance is not coated on the non-luminous portion in the curved portion of the U-shaped lamp,
- wherein a spacing interval between the curved portions of the opposite U-shaped lamps is smaller than a width of the non-luminous portion,
- wherein a diameter of each of the U-shaped lamps is to 4 mm,
- wherein optical sheets are provided above the U-shaped lamps,
- wherein the optical sheets are formed of a light-diffusion sheet, a prism sheet and a protection sheet,
- wherein a reflective sheet is provided below the U-shaped lamps, and
- wherein a case is provided for receiving and fixing the U-shaped lamps, the optical sheets, and the reflective sheet;
- wherein a width of the non-luminous portion is 5 mm;
- and
- wherein the curved portions of the opposite U-shaped lamps are symmetrically maintained at a spacing interval of 1 mm.
8 more elements
A backlight unit, comprising:
- a first U-shaped lamp having a first straight section, a second straight section, and a curved section intermediate the first straight section and the second straight section such that the first straight section is located beside and generally parallel to the second straight section,
- a second U-shaped lamp having a first straight segment, a second straight segment, and a curved segment intermediate the first straight segment and the second straight segment such that the first straight segment is located beside and generally parallel to the second straight segment,
- wherein the curved section of the first U-shaped lamp and the curved segment of the second U-shaped lamp are positioned adjacent to one another with a spacing interval of 1 mm therebetween,
- wherein the curved section of the first U-shaped lamp comprises a non-luminous portion,
- wherein a fluorescent substance is provided on an interior surface of the first straight section and the second straight section, and a fluorescent substance is not provided on an interior surface of the portion of the curved section that comprises the non-luminous portion,
- wherein the first and second U-shaped lamps are symmetrically arranged with the curved sections of the first and second U-shaped lamps facing each other, so as to provide a uniform luminance across the first and second U-shaped lamps,
- wherein a spacing interval between the curved sections of the opposite U-shaped lamps is smaller than a width of the non-luminous portion,
- wherein each diameter of the first and second U-shaped lamps is 3 to 4 mm,
- wherein optical sheets are provided above the first and second U-shaped lamps,
- wherein the optical sheets are formed of a light-diffusion sheet, a prism sheet and a protection sheet,
- wherein a reflective sheet is provided below the first and second U-shaped lamps,
- wherein a case is provided for receiving and fixing the first and second U-shaped lamps, the optical sheets, and the reflective sheet;
- and
- wherein a width of the non-luminous portion is 5 mm.
11 more elements
A method of making a direct type backlight unit, the method comprising:
- forming a plurality of U-shaped lamps having curved portions that are non-luminous portions;
- arranging the plurality of U-shaped lamps in two columns so that the curved portions of two opposite U-shaped lamps are symmetrically positioned in a center of a display area, so as to provide a uniform luminance across the plurality of U-shaped lamps;
- providing optical sheets above the plurality of U-shaped lamps, the optical sheets including a light-diffusion sheet, a prism sheet and a protection sheet;
- providing a reflective sheet below the plurality of U-shaped lamps;
- and
- providing a case to receive and fix the plurality of U-shaped lamps, the optical sheets, and the reflective sheet.
- wherein a fluorescent substance is not coated on the non-luminous portions in the curved portions of the plurality of U-shaped lamps,
- wherein a spacing interval between the curved portions of the opposite U-shaped lamps is smaller than a width of the non-luminous portion;
- wherein a width of the non-luminous portion is 5 mm,
- wherein the curved portions of the opposite U-shaped lamps are symmetrically maintained at a spacing interval of 1 mm, and
- wherein a diameter of each of the U-shaped lamps is 3 to 4 mm.
8 more elements
Dependencies are inferred from the claim text.