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1. (WO2005064390) PANNEAU LUMINEUX ET APPAREIL D'AFFICHAGE A ECRAN PLAT EQUIPE DE CET ENSEMBLE
Note: Texte fondé sur des processus automatiques de reconnaissance optique de caractères. Seule la version PDF a une valeur juridique

Description
BACKLIGHT ASSEMBLY AND FLAT PANEL DISPLAY

APPARATUS HAVING THE SAME
Technical Field
[1] The present invention relates to a backlight asserr y and a flat panel dsplay
apparatus having the backlight asseπtøy. More particularly, the present invention relates to a backlight asseπtøy capable of providng a light having a uniform
brightness dstribution and a flat panel dsplay apparatus having the backlight
asseπWy.
Background Art
[2] In general, in order to visually confirm information processed in an information- processing device, a flat panel dsplay apparatus for a role as an interface dsplays an image in response to an image signal externally provided.
[3] A liquid crystal dsplay apparatus, which is one of the flat panel dsplay apparatus, uses optical properties of liquid crystal so as to dsplay an image. A liquid crystal dsplay apparatus, generally, includes a liquid crystal dsplay panel that dsplays an image correspondng to an image signal using a light and a backlight asseπi>ly that provides the light to the liquid crystal dsplay apparatus.
[4] The backlight asseπWy is classified into an edge type backlight asseπtøy and a drect illumination type backlight asseπtøy in accordance with a position where a light source that is emitting the Ught is positioned.
[5] The edge type backlight asseπWy has at least one light source dsposed at a
position adjacent to a side face of a light guide plate. The drect illumination type backlight asseπtøy has a plurality of light sources dsposed under the liquid crystal dsplay panel. The Ught sources of the drect illumination type backlight asseπtøy drectly irradate the light over the liquid crystal dsplay panel.
[6] The drect illumination type backlight asseπtøy has a dffusing plate dsposed
between the light sources and the liquid crystal dsplay panel, a supporting member that maintains an interval between the Ught sources and the dffusing plate, a reflecting plate that reflects the light from the light sources to the dffusing plate, and a receiving container that receives the light sources.
[7] The supporting member dsposed between the reflecting plate and the dffusing plate is dsposed on the reflecting plate. Thus, the supporting member partially covers an upper face of the reflecting plate, and the covered area of the upper face of the reflecting plate may not reflect the light from the Ught sources to the dffusing plate.
That is, the covered area of the reflecting plate has reflectance lower than reflectance at an area not covered by the supporting member, so that the reflecting plate may not uniformly provide the light to the dffusing plate. As a result, a dsplay quality of the liquid crystal dsplay apparatus may be deteriorated.
Disclosure of Invention
Technical Problem
[8] The present invention provides a backlight asseπi>ly capable of providng a light having a uniform brightness dstribution.
[9] The present invention provides a flat panel dsplay apparatus having the above
backlight asseπi>ly.
Technical Solution
[10] In one aspect of the present invention, a backlight asseπtøy includes a lamp
emitting a light, a dffusing member, a reflecting member and supporting member.
[11] The dffusing member dffuses the light provided from the lamp. The reflecting
member is dsposed under the lamp to reflect the light provided from the lamp to the dffusing member. The supporting member is dsposed under the reflecting member to support the dffusing member. The supporting member partially passes through the reflecting member and is upwardly protruded with respect to the reflecting member.
[12] In another aspect of the present invention, a flat panel dsplay apparatus includes a dsplay panel and a backlight asseπWy.
[13] The dsplay panel dsplays an image using a light externally provided.
[14] The backlight asseπWy has a lamp emitting a light, a dffusing member, a
reflecting member and supporting member. The dffusing member dffuses the light provided from the lamp and provides the dffused light to the dsplay panel. The
reflecting member is dsposed under the lamp to reflect the light provided from the lamp to the diffusing member. The supporting member is dsposed under the reflecting member to support the dffusing member. The supporting member partially passes
through the reflecting member and is upwardly protruded with respect to the reflecting member.
[15] Accordng to the backlight asseπtøy and the flat panel dsplay apparatus, since a portion of the supporting member is dsposed on the reflecting member, the backlight asseπWy may provide the light having uniform brightness dstribution to the dsplay panel.

Brief Description of the Drawings
[16] The above and other advantages of the present invention will become readly
apparent by reference to the following detailed description when considered in
conjunction with the accompanying drawings wherein:
[17] FIG. 1 is a cross-sectional view showing a flat panel dsplay apparatus accordng to an exemplary embodment of the present invention;
[18] FIG. 2 is a cross-sectional view showing the backlight asseπi>ly shown in FIG. 1 ;
[19] FIG. 3 is an exploded perspective view showing the reflecting plate and the
receiving container shown in FIG. 2;
[20] FIG. 4 is a plane view showing the backlight asseπi>ly shown in FIG. 2;
[21] FIG. 5 is a cross-sectional view showing a backlight asseπtøy accordng to another exemplary embodment of the present invention;
[22] FIG. 6 is a plane view showing the backlight asseπtøy shown in FIG. 5; and
[23] FIG. 7 is a perspective view showing the receiving container shown in FIG. 4.
Best Mode for Carrying Out the Invention
[24] Hereinafter, the present invention will be explained in detail with reference to the accompanying drawings.
[25] FIG. 1 is a cross-sectional view showing a flat panel dsplay apparatus accordng to an exemplary embodment of the present invention.
[26] Referring to FIG. 1, a flat panel dsplay apparatus 500 includes a liquid crystal dsplay panel 100 that dsplays an image using a light, a backlight asseπtøy 200 that provides the light to the liquid crystal dsplay panel 100, a first mold frame 300 that receives the liquid crystal dsplay panel 100, and a top chassis 400.
[27] The liquid crystal dsplay panel 100 has a thin film transistor substrate 110, a color filter substrate 120 coupled to the thin film transistor substrate 110, and a liquid crystal layer (not shown) dsposed between the thin film transistor substrate 110 and the color filter substrate 120.
[28] The thin film transistor substrate 110 is a transparent substrate on which thin film transistors are formed in a matrix configuration. The color filter substrate 120 facing the thin film transistor substrate 110 is a transparent substrate formed in a thin film process. Red (R), green (G) and blue (B) color pixels are formed on the color filter substrate 120.
[29] The backlight asseπWy 200 dsposed under the liquid crystal dsplay panel 100
uniformly provides the light to the liquid crystal dsplay panel 100.

[30] The backlight asserrbly 200 includes a plurality of lamp 210 that emits the light, a dffusing plate 220 and a dffusing sheet 230 that dffuse the light, a second mold
frame 250 that receives the lamps 210, a reflecting plate 240 and the lamps 210, and a supporting member 270 that maintains an interval between the receiving container 260 and the dffusing plate 220.
[31] Particularly, the lamps 20 emit the light in response to a power voltage externally provided. The lamps 210 are dsposed under an effective dsplay area of the liquid crystal dsplay panel 100 on which the image is dsplay ed. The lamps 210 are arranged in parallel to each other to provide the light to the liquid crystal dsplay panel 100. In FIG. 1, the lamps 210 have a first lamp 211 and a second lamp 212, but the flat panel dsplay apparatus 500 may have substantially more than two lamps.
[32] The dffusing plate 220 and the dffusing sheet 230 are sequentially dsposed
between the lamps 210 and the liquid crystal dsplay panel 100. The dffusing plate
220 and the dffusion sheet 230 dffuse the light emitted from the lamps 210, and
provide the dffused light to the liquid crystal dsplay panel 100.
[33] The reflecting plate 240 is dsposed under the lamps 210. The reflecting plate 240 reflects the light emitted from the lamps 210 to the dffusing plate 220 so as to enhance a light efficiency. The reflecting plate 240 has a plurality of engaging openings
through which a portion of the supporting member 270 passes.
[34] The second mold frame 250 receives the lamps 210, the diffusing plate 220 and the dffusion sheet 230. The second mold frame 250 has a bottom plate partially opened and a sidewall extended from the bottom plate. The lamps 210 are dsposed on the bottom plate of the second mold frame 250. The second mold frame 250 has a stepped portion 251 protruded from the sidewall so as to sequentially receive the dffusing plate 220 and the dffusing sheet 230.
[35] In this exemplary embodment, in order to uniformly provide the light to the Uquid crystal dsplay panel 100, the lamps 210 are dsposed at positions spaced apart from the dffusing plate 220 in a predetermined dstance. Also, the lamps 210 are spaced apart from each other in a predetermined dstance.
[36] The second mold frame 250 is coupled to the receiving container 260. The
receiving container 260 receives the reflecting plate 240 and the lamps 210. The
receiving container 260 has a plurality of openings formed through an area cor- respondng to the engaging openings formed through the reflecting plate 240 such that the supporting member 270 is inserted.
[37] A portion of the supporting member 270 is dsposed under the receiving container 260. The supporting member 270 supports the dffusing plate 220 such that the
dstance between the lamps 210 and the dffusing plate 220, and also supports the lamps 210 to be uniformly spaced apart from each other.
[38] The supporting member 270 is coupled to the receiving container 270. A nun±>er of supporting members may increase or decrease dependng upon a size of the flat panel dsplay apparatus 500.
[39] The first mold frame 300 is dsposed on the backlight assembly 200. The mold frame 300 has a bottom plate partially opened such that the light from the backlight assembly 200 dsposed under the first mold frame 300 is provided to the Uquid crystal dsplay panel 100. The first mold frame 300 receives the liquid crystal dsplay panel
100. The first mold frame 300 is coupled to the second mold frame 250 so as to fix the dffusing plate 220 and the dffusing sheet 230 to the second mold frame 250.
[40] The top chassis 400 is dsposed on the liquid crystal dsplay panel 100. The top chassis 400 is coupled to the receiving container 260 to fix the liquid crystal dsplay panel 100 to the first mold frame 300. The top chassis 400 covers edge of the liquid crystal dsplay panel 100 except for the effective dsplay area on which the image is dsplayed.
[41] FIG. 2 is a cross-sectional view showing the backlight assembly shown in FIG. 1.

FIG. 3 is an exploded perspective view showing the reflecting plate and the receiving container shown in FIG. 2. In FIG. 2, in order to clearly show the receiving container 260 and the supporting member 270, the second mold frame 250 and the dffusing sheet 230 are omitted.
[42] Referring to FIGS. 2 and 3, the reflecting plate 240 is dsposed on the receiving container 260, and a portion of the supporting member 270 is dsposed under the
receiving container 260.
[43] The supporting member 270 includes a base body portion 271, a plurality of lamp holder 272 that receives the lamps 210 so as to fix the lamps 210 to predetermined positions, and a supporting portion 273 that supports the dffusing plate 220.
[44] Particularly, an upper face of the base body portion 271 of the supporting member

270 makes contact with a rear face of the receiving container 260.
[45] The lamp holders 272 are protruded from the upper face of the base body portion
271. The lamp holders 22 have a first lamp holder 272a and a second lamp holder
272b. In this exemplary embodment, the supporting member 270 has the first and second lamp holders 272a and 272b, but nuπi>er of the lamp holders 272 may be
varied in accordance with nuπi>er of the lamps 210.

[46] The first lamp holder 272a receives the first lamp 211 of the lamps 210 so as to fix the first lamp 211 to a predetermined position. The first lamp holder 272a includes a first wing portion 71 and a second wing portion 72 that is integrally formed with the first wing portion 71 so as to hold a portion of an outer face of the first lamp 211.
[47] In this exemplary embodment, the second lamp holder 272b has structure substantially identical to the first lamp holder 272a, and thus a detailed description of the second lamp holder 272b will be described.
[48] The second lamp holder 272b receives a second lamp 212 of the lamps 210 so as to fix the second lamp 212 to a predetermined position.
[49] The supporting portion 273 is dsposed between the first and second lamp holders
272a and 272b. The supporting portion 273 is protruded from the base body portion
271 toward a drection where the first and second lamp holders 272a and 272b are
protruded so as to support the dffusing plate 220. The supporting portion 273 has a coupling protrusion 73 dsposed at a position spaced apart from the base body portion
271 and protruded toward a longitudnal drection of the base body portion 271. When the supporting member 270 is inserted into the opening of the receiving container 260, the coupling protrusion 73 is coupled to the upper face of the receiving container 260, thereby preventing the supporting member 270 from being separating from the
receiving container 260.
[50] Referring to FIG. 3, the reflecting plate 240 has a first engaging opening 241
formed through the bottom thereof and a second engaging opening 242 formed through the bottom thereof. The first and second lamp holders 272a and 272b are inserted into the second engaging opening 242, and the supporting portion 273 is inserted into the first engaging opening 241. The second engaging opening 242 has a first holder
engaging opening 242a through which the first lamp holder 272a is inserted and a
second holder engaging opening 242b through which the second lamp holder 272b is inserted. The first engaging opening 241 is dsposed between the first and second
holder engaging openings 242a and 242b.
[51] The receiving container 260 includes a bottom plate 261 on which the reflecting plate 240 is dsposed and a sidewall 262 extended from an edge of the bottom plate
261 to provide a receiving space. The receiving container 260 includes a first opening 263 formed through the bottom plate 261 thereof and a second opening 264 formed through the bottom plate 261 thereof. The first opening 263 is formed at a position cor- respondng to the first engaging opening 241 and the second opening 264 is formed at a position correspondng to the second engaging opening 242.

[52] The second opening 264 has a first holder opening 264a and a second holder
opening 264b correspondng to the first and second holder engaging openings 242a and 242b, respectively. Nurrbers of the openings formed through the receiving
container 260 are identical to nuπi>ers of the engaging openings formed through the reflecting plate 240.
[53] The supporting portion 273 is inserted inside the receiving container 260 after sequentially passing through the first opening 263 and the first engaging opening 241. The coupling protrusion 73 of the supporting portion 273 is inserted inside the
receiving container 260, and coupled to the bottom plate 261 in a hook-type manner. In this exemplary eπiodment, the first opening 263 has a width Dl that is smaller than a width D2 at which the coupUng protrusion 73 is formed. Thus, the supporting portion 273 inserted inside the receiving container 260 may be not separated from the
receiving container 260 by the hook-type manner of the coupling protrusion 73 and the receiving container 260.
[54] Although not shown in FIGS, a width of the first engaging opening 241 may be identical to or greater than the width Dl of the first opening 263. In case that the width of the first engaging opening 241 is greater than the width Dl of the first opening 263, the width of the first engaging opening 241 is identical to the width D2 at which the coupling protrusion 73 is formed. Thus, the coupUng protrusion 73 may be coupled to the reflecting plate 240 in the hook-type manner.
[55] The first lamp holder 272a is inserted inside the receiving container 260 after sequentially passing through the first holder opening 264a and the first holder engaging opening 242a. The second lamp holder 272b is also inserted inside the receiving
container 260 after sequentially passing through the second holder opening 264b and the second holder engaging opening 242b.
[56] FIG. 4 is a plane view showing the backlight asseπi>ly shown in FIG. 2. In FIG. 4, in order to clearly show the reflecting plate 240 and the supporting member 270, the dffusing plate 220 and the receiving container 260 are omitted.
[57] Referring to FIG. 4, when the reflecting plate 240 is con±ined with the receiving container 260, the first lamp holder 272a of the supporting member 270 is dsposed on the reflecting plate 240 after sequentially passing through the first holder opening 264a of the receiving container 260 and the first holder engaging opening 242a of the
reflecting plate 240. The second lamp holder 272b of the supporting member 270 is also dsposed on the reflecting plate 240 after sequentially passing through the second holder opening 264b of the receiving container 260 and the second holder engaging opening 242b of the reflecting plate 240. The supporting portion 273 of the supporting member 270 is also dsposed on the reflecting plate 240 after sequentially passing
through the first opening 263 of the receiving container 260 and the first engaging opening 241 of the reflecting plate 240. The base body portion 271 of the supporting member 270 is dsposed under the receiving container 260 and the reflecting plate.
[58] That is, the first lamp holder 272a, the second lamp holder 272b and the supporting portion 273 are dsposed on the reflecting plate 240, but the base body portion 271 is dsposed under the reflecting plate 240.
[59] In other words, the first and second lamp holders 272a and 272b holdng the first and second lamps 211 and 212 and the supporting portion 273 supporting the dffusing plate 220 of the supporting member 270 are dsposed on the reflecting plate 240, and the base body portion 271 is dsposed under the reflecting plate 240 of the supporting member 270.
[60] The first lamp holder 272a and the second lamp holder 272b and the supporting portion 273 dsposed on the reflecting plate 240 are fixed to the receiving container
260 by the hook-type manner between the coupling protrusion 73 protruded from the supporting portion 273 and the receiving container 260. Thus, an area of the reflecting plate 240 covered by the supporting member 270 may be reduced.
[61] As a result, an area of the reflecting plate 240 that reflects the light emitted from the lamps 210 may increase, and the reflecting plate 240 may uniformly reflect the light over the whole area thereof. Thus, the backlight asserr y 200 may provide the light having uniform light dstribution to the liquid crystal dsplay panel 100 so that the flat panel dsplay apparatus 500 may improve dsplay quality of the image dsplayed
thereon.
[62] FIG. 5 is a cross-sectional view showing a backlight asseπtøy accordng to another exemplary embodment of the present invention.
[63] Referring to FIG. 5, a backUght asseπtøy 600 accordng to another exemplary
embodment of the present invention has same structure as the backlight asseπtøy 200 shown in FIG. 2 except for a reflecting plate 610, a supporting member 620 and a receiving container 630. Therefore, in FIG. 5, the same reference numerals denote the same elements in FIG. 2, and thus the detailed descriptions of the same elements will be omitted.
[64] The backlight asseπWy 600 includes a plurality of lamps 210, a dffusing plate 220 that dffuses a light emitted from the lamps 210, the reflecting plate 610 that reflects the light from the lamps 210 to the dffusing plate 220, the supporting member 620 that uniformly maintains an interval between the lamps 210 and the dffusing plate 220 and the receiving container 630.
[65] In FIG. 5, the lamps 210 have a first lamp 211 and a second lamp 212, but the flat panel dsplay apparatus 500 may have substantially more than two lamps.
[66] The first and second lamps 211 and 212 are arranged in parallel to each other so as to uniformly provide the light to the liquid crystal dsplay panel 100 (not shown, refer to FIG. 1) The first and second lamps 211 and 212 are spaced apart from the dffusing plate 220, and each of the first and second lamps 211 and 212 is spaced apart from each other in a predetermined interval.
[67] More particularly, the dffusing plate 220 is dsposed on the first and second lamps

211 and 212, and the reflecting plate 610 is dsposed under the first and second lamps 211 and 212.
[68] The reflecting plate 610 has a plurality of engaging openings into which a portion of the supporting member 620 is inserted.
[69] A remaining portion of the supporting member 620 is dsposed under the reflecting plate 610. The supporting member 620 has a base body portion 621, a plurality of lamp holders 622 that fixes the first and second lamps 211 and 212 to a predetermined
position, and supporting portion 623 that supports the dffusing plate 220.
[70] Particularly, an upper face of the base body portion 621 dsposed under the
reflecting plate 610 makes contact with a lower face of the reflecting plate 610.
[71] The lamp holders 622 are protruded from the upper face of the base body portion
621. The lamp holders 622 have a first lamp holder 622a and a second lamp holder
622b. In this exemplary embodment, the supporting member 620 has two lamp
holders, but nuπi>ers of the lamp holders may be varied in accordance with nuπi>ers of the lamps 210.
[72] The first lamp holder 622a receives the first lamp 211 of the lamps 210 so as to fix the first lamp 211 to a predetermined position. The first lamp holder 622a includes a first wing portion 61 and a second wing portion 62 that is integrally formed with the first wing portion 61 so as to hold a portion of an outer face of the first lamp 211.
[73] In this exemplary embodment, the second lamp holder 622b has structure substantially identical to the first lamp holder 622a. Thus, a detailed description of the second lamp holder 622b will be omitted.
[74] The second lamp holder 622b receives the second lamp 212 of the lamps 210 so as to fix the second lamp 212 to a predetermined position.
[75] The supporting portion 623 is dsposed between the first and second lamp holders 622a and 622b. The supporting portion 623 is protruded from the base body portion
621 toward the dffusing plate 220 to support the dffusing plate 220.
[76] The first lamp holder 622a, the second lamp holder 622b and the supporting portion

623 are inserted through a plurality of engaging holes formed through the reflecting plate 610 toward the dffusing plate 220.
[77] The reflecting plate 610 has a first engaging hole 611 into which the supporting portion 623 is inserted and a second engaging hole into which the first and second lamp holders 622a and 622b is inserted.
[78] The second engaging hole has a first holder engaging hole 612 into which the first lamp holder 622a is inserted and a second holder engaging hole 613 into which the second lamp holder 622b is inserted. The first engaging hole 611 is dsposed between the first and second holder engaging holes 612 and 613.
[79] The reflecting plate 610 and the supporting member 620 are received into the
receiving container 630. In order to receive the base body portion 621 of the
supporting member 620, the receiving container 630 has a receiving recess 31 formed at a bottom plate thereof. The receiving container 630 may prevent separation of the reflecting plate 610 from the bottom plate of the receiving container 630.
[80] An adhesive member 640 is dsposed between the base body portion 621 of the
supporting member 620 and the receiving container 630. The adhesive member 640 adheres the base body portion 621 of the supporting member 620 to a bottom face of the receiving recess 31 to improve coherence between the supporting member 620 and the receiving container 630.
[81] FIG. 6 is a plane view showing the backlight asseπtøy shown in FIG. 5. In FIG. 6, in order to clearly show the reflecting plate 610 and the supporting member 620, the dffusing plate 220 and the receiving container 630 will be omitted.
[82] Referring to FIG. 6, when the supporting member 620 is coupled to the reflecting plate 610, the first lamp holder 622a and the second lamp holder 622b of the
supporting member 620 are dsposed on the reflecting plate 610 after passing through the first holder engaging opening 612 and the second holder engaging opening 613 of the reflecting plate 610. The supporting portion 623 of the supporting member 620 is also dsposed on the reflecting plate 610 after passing through the first engaging
opening 611 dsposed between the first and second holder engaging openings 612 and 613 of the reflecting plate 610. The base body portion 621 of the supporting member
610 is dsposed under the reflecting plate 610.
[83] That is, the first lamp holder 622a, the second lamp holder 622b and the supporting portion 623 are dsposed on the reflecting plate 610, but the base body portion 621 is dsposed under the reflecting plate 610.
[84] In other words, since the base body portion 621 of the supporting member 610 is dsposed under the reflecting plate 610, an area of the reflecting plate 610 covered by the supporting member 620 may be reduced. As a result, an area of the reflecting plate 610 that reflects the light emitted from the lamps 210 may increase, and the reflecting plate 610 may uniformly reflect the Ught over the whole area thereof. Thus, the
backlight asseπi>ly 600 may provide the light having uniform light dstribution to the liquid crystal dsplay panel (not shown)
[85] FIG. 7 is a perspective view showing the receiving container shown in FIG. 4.
[86] Referring to FIG. 7, the receiving container 630 has a bottom plate 631 on which the supporting member 620 and the reflecting plate 610 are sequentially dsposed and a sidewall 632 extended from an edge of the bottom late 631 to provide a receiving space.
[87] Particularly, the receiving recess 31 is formed at the bottom plate 631 of the
receiving container 630 so as to receive the base body portion 621 of the supporting member 620. The receiving recess 31 is formed by partially recessing the bottom plate 631 of the receiving container 610. Thus, the bottom plate 631 of the receiving
container 630 correspondng to the receiving recess 31 is outwardly protruded such that a receiving space of the receiving recess 31 may be sufficiently obtained. As a result, the receiving container 630 may prevent separation of the reflecting plate 610 from the bottom plate 631 of the receiving container 630. In this exemplary
errbodment, a depth of the receiving recess 31 is substantially equal to a thickness that is a sum of thicknesses of the base body portion 621 and the adhesive member
640.
[88] Accordng to the present invention, the backlight asseπtøy has the lamps, the
reflecting plate dsposed under the lamps and the dffusing plate dsposed on the
lamps. The backlight asseπtøy also further has the lamp holder uniformly maintaining the interval between the lamps and the supporting member having the supporting portion supporting the dffusing plate. The reflecting plate has the engaging openings, the lamp holder and the supporting portion inserted through the engaging openings, and the base body portion integrally formed with the lamp holder and the supporting portion is dsposed under the reflecting plate.
[89] Thus, the area of the reflecting plate covered by the supporting member may be reduced. Therefore, the flat panel dsplay apparatus may enhance an amount of the light reflected from the reflecting plate and uniformity of the light, thereby improving the dsplay quality of the image.
[90] Although the exemplary embedments of the present invention have been described, it is understood that the present invention should not be limited to these exemplary em- bodments but various changes and modfications can be made by one ordnary skilled in the art within the spirit and scope of the present invention as hereinafter claimed.