KR20060094777A - Liquid crystal display - Google Patents

Abstract

The present invention relates to a liquid crystal display device, comprising: a liquid crystal panel on which an image is formed; A light adjusting plate disposed at the rear of the liquid crystal panel; A light source unit provided along at least one side of the light control plate to supply light to the liquid crystal panel; It guides the light emitted from the light source to the light control plate, characterized in that it comprises a reflector provided with a diffuse reflection pattern.

As a result, the luminance is uniform and light efficiency and color reproducibility can be improved.

Description

Liquid Crystal Display {Liquid Crystal Display}

1 is a perspective view showing a liquid crystal display device according to a first embodiment of the present invention;

FIG. 2 is a perspective view illustrating a partial configuration of a backlight unit to which a reflector manufactured by molding in FIG. 1 is applied;

3 to 5 are cross-sectional views each illustrating a part of a backlight unit to which a reflector manufactured by mold processing is applied in a liquid crystal display device according to a second to fourth embodiments of the present invention.

FIG. 6 is a perspective view illustrating a part of a configuration of a backlight unit to which a reflector manufactured by pressing is applied in a liquid crystal display according to a fifth embodiment of the present invention;

7 to 9 are cross-sectional views each showing a partial configuration of a backlight unit to which a reflector manufactured by press working is applied in a liquid crystal display device according to sixth to eighth embodiments of the present invention;

10 and 11 are perspective views illustrating an arrangement state of an LED light source unit and a reflector in the liquid crystal display according to the ninth embodiment of the present invention.

* Explanation of symbols for the main parts of the drawings

1: liquid crystal display device 100: liquid crystal panel

Diffuse reflection pattern: 180, 280, 380, 480, 580, 680, 780, 880, 980

300: backlight unit 310: light control plate

320: LED light source unit 321, 322, 323: LED

325 LED LED 330 Reflector

350: Optical sheet

The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device with uniform brightness and improved light efficiency and color reproducibility.

The liquid crystal display device has a liquid crystal panel composed of a thin film transistor substrate, a color filter substrate, and liquid crystal injected between both substrates. The liquid crystal display further includes a backlight unit for supplying light to the liquid crystal panel because the liquid crystal panel is a non-light emitting device. At this time, the amount of light emitted from the backlight unit is adjusted according to the arrangement of the liquid crystals. The liquid crystal panel and the backlight unit are housed in the chassis.

Such a backlight unit is classified into an edge type and a direct type according to the position of the light source.

Here, the edge type backlight unit is mainly applied to a liquid crystal display device having a relatively small size, such as a monitor of a laptop computer and a desktop computer or a monitor of a portable terminal. The backlight unit includes a light guide plate disposed behind the liquid crystal panel, a light source disposed along at least one side of the light guide plate to supply light to the liquid crystal panel, a reflector that reflects light emitted from the light source and guides the light guide plate to the light guide plate. It is disposed on the top and comprises an optical sheet for diffusing and condensing the light guided by the light guide plate.

In this case, EL (Electro Luminescence), Cold Cathode Fluorescent Lamp (CCFL), Hot Cathode Fluorescent Lamp (HCFL), Light Emitting Diode (LED), and the like are used as the light source.

The LED (LED) light source includes an LED PCB and a plurality of LEDs mounted on the LED PCB and emitting red, green, and blue light, respectively. Accordingly, the LED light source may mix light emitted from each of the R, G, and B LEDs to form white light, and supply the white light to the liquid crystal panel.

The reflector includes a reflecting surface that reflects light emitted from the LED light source and guides the light guide plate. The reflector is composed of a structure surrounding the LED light source is fitted to be coupled to the side of the light guide plate.

With this configuration, the light emitted from the LED light source can be reflected by the reflector and incident on the light guide plate, and then can be diffused and collected by the optical sheets and supplied to the liquid crystal panel. In addition, since the LED light source uses a DC voltage of about 1.5V, the DA-AC converter is not necessary, thereby minimizing power consumption.

By the way, in such a conventional liquid crystal display device, there is a problem in that the luminance line is separated from the dark line where light is emitted and the dark line where the light is not emitted. In addition, the red (R), green (G), blue (B) light emitted from each RGB LED is not uniformly mixed, there is a problem that the light efficiency and color reproducibility is reduced.

Accordingly, an object of the present invention is to provide a liquid crystal display device with uniform luminance and improved light efficiency and color reproducibility.

The object is, according to the present invention, a liquid crystal panel in which an image is formed; A light adjusting plate disposed at the rear of the liquid crystal panel; A light source unit provided along at least one side of the light control plate to supply light to the liquid crystal panel; The light emitted from the light source unit is guided to the light control plate, and is achieved by a reflector provided with a diffuse reflection pattern.

The light source unit may include an LED light source unit having a plurality of LEDs respectively emitting red (R), green (G), and blue (B) light.

Here, the diffuse reflection pattern is preferably provided with a plurality of protrusions to uniformly mix the light emitted from each of the LEDs.

The LED light source unit may further include an LED PC, the LED is arranged on the LED PC line at a predetermined interval, the protrusions are provided in a band shape, can be arranged to be connected to each other in the horizontal direction of the LED array direction. have.

The LED light source unit may further include an LED PC, the LEDs are arranged in a line at a predetermined interval on the LED PC, the protrusion is provided in a band shape, may be spaced apart in the horizontal direction of the LED array direction.

The protrusion may diffusely reflect light emitted from the LED, including a prism shape.

The protrusion may diffusely reflect light emitted from the LED, including a hemispherical shape.

The protrusion may diffusely reflect light emitted from the LED, including a wave shape.

The protrusion may include a rectangular shape and diffusely reflect light emitted from the LED.

The reflector may be manufactured by mold processing or press working.

The LED light source unit may further include an LED PC, the LED is arranged in a line at a predetermined interval on the LED PC, the protrusion is provided in a band shape, it may be arranged in a direction parallel to the LED array direction.

Here, the protrusion may be provided in a wave shape and disposed to face the LED.

The protrusion may be provided in a wave shape, and the LED may be disposed to face each other between the protrusions.

The reflector may further include a reflective surface, and the diffuse reflection pattern may be provided on the reflective surface.

The diffuse reflection pattern may be integrally formed with the reflective surface, or may be manufactured in a film type and adhered to the reflective surface.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Prior to the description, in various embodiments, components having the same configuration will be representatively described in the first embodiment using the same reference numerals, and in other embodiments, only the configuration different from the first embodiment will be described. would.

As shown in FIG. 1, the liquid crystal display device 1 according to the first exemplary embodiment of the present invention includes a liquid crystal panel 100, a source printed circuit board 130 and gate printing for driving the liquid crystal panel 100. An upper chassis to accommodate the circuit board 140, the backlight unit 300 disposed behind the liquid crystal panel 100 to supply light to the liquid crystal panel 100, and the liquid crystal panel 100 and the backlight unit 300. 150 and the lower chassis 160.

The liquid crystal panel 100 includes a thin film transistor substrate 110 on which a thin film transistor is formed, a color filter substrate 120 provided to face the thin film transistor substrate 110, and a liquid crystal layer injected between both substrates 110 and 120. Not shown). In the liquid crystal panel 100, an image is formed according to the arrangement of the liquid crystal layer. Since the liquid crystal panel 100 is a non-light emitting device, the backlight unit 300 is required.

The driving signals provided from the source printed circuit board 130 and the gate printed circuit board 140 are applied to the liquid crystal panel 100 through the data flexible circuit film 135 and the gate flexible circuit film 145. The data flexible circuit film 135 and the gate flexible circuit film 145 respectively provide data for applying driving signals provided from the source printed circuit board 130 and the gate printed circuit board 140 to the liquid crystal panel 100. The driving chip 133 and the gate driving chip 143 are mounted.

The backlight unit 300 may include a light control plate 310 disposed behind the liquid crystal panel 100; A light source unit 320 provided along both sides of the light control plate 310 to supply a ball to the liquid crystal panel 100; The light emitted from the light source 320 is guided to the light control plate 310, and includes a reflector 330 having a diffuse reflection pattern 180. At this time, the backlight unit 300 is disposed on the light control plate 310 and the optical sheet 350 to diffuse and condense the light passing through the light control plate 310 to supply to the liquid crystal panel 100 and The light control plate 310 further includes a reflector (not shown) disposed at a lower portion of the light control plate 310 to reflect back the light leaking in the opposite direction of travel to the light control plate 310.

The optical sheet 350 has a diffuser film 351 having a bead-shaped coating layer formed thereon to diffuse light from the light control plate 310, and an upper portion of the liquid crystal panel 100 provided on the diffuser film 351. And a protective film 353 provided between the liquid crystal panel 100 and the prism film 352 to protect the prism film 352.

The diffusion film 351 can use two or three sheets at a time.

Two prism films 352 are usually used, and the micro prisms formed on each prism film form an angle. Most of the light passing through the prism film 352 proceeds vertically to uniformly form luminance.

The light control plate 310 is preferably provided with a light guide plate for guiding the light supplied from the side portion to the liquid crystal panel 100.

The light source unit 320 includes an LED light source unit having a plurality of LEDs 321, 322, and 323 that emit red, green, and blue light, respectively. The LED light source unit 320 includes an LED PC 325 and a plurality of LEDs 321, 322, and 323 arranged in a predetermined interval on the LED PC 325. Accordingly, the light emitted from each of the R, G, and B LEDs 321, 322, and 323 may be mixed and made into white light and supplied to the liquid crystal panel 100.

The reflector 330 is disposed along both side edges of the light control plate 310 and is provided to have a structure surrounding the LED light source unit 320 to be coupled to both side edges of the light control plate 310. The reflector 330 is manufactured by mold processing, and includes reflecting surfaces 335 and 336 reflecting light toward the light control plate 310, and a diffuse reflection pattern 180 provided on the reflecting surface 336. Here, the LED light source 320 and the reflector 330 is provided on both sides of the light control plate 310, but may be disposed only on one side.

The reflective surface has a first reflection surface 335 on which the LED light source unit 320 is seated and one end thereof contacts the lower surface of the light control plate 310, and has an arc shape and extends upwardly from the first reflection surface 335. And a second reflecting surface 336 in contact with the upper surface of the light control plate 310.

The diffuse reflection pattern 180 is formed on the second reflection surface 336, and the diffuse reflection pattern 180 is provided with a plurality of protrusions protruding toward the LEDs 321, 322, and 323. Accordingly, the light emitted from each of the R, G, and B LEDs 321, 322, and 323 is diffusely reflected by the protrusions 180 to be uniformly mixed. Therefore, since uniformly mixed white light is supplied to the liquid crystal panel 100, the luminance is uniform and light efficiency and color reproducibility may be improved.

The protrusion 180 is formed at an approximately center region of the second reflective surface 336. In addition, an end region of the second reflective surface 336 which is a mirror surface is combined with an upper surface of the light adjusting plate 310, and an end region of the first reflective surface 335 which is a mirror surface is a lower surface of the light adjusting plate 310. Combined with

The protrusions 180 have a prism shape, and are arranged in a band shape so as to be connected to each other in the horizontal direction of the LEDs 321, 322, and 323 array directions. In this case, the protrusion 180 may be directly formed in the prism shape on the second reflective surface 336, or may be manufactured in a film type and adhered to the second reflective surface 336. Here, although the plurality of protrusions 180 are arranged to be connected to each other, of course, the diffuse reflection may be arranged to be spaced apart from each other within a range that can be efficiently.

Here, the reflector 330 may be formed of a sus (SUS) or brass (BRASS) of aluminum (Al) or stainless steel. In addition, in order to improve the reflection efficiency, a high luminance liquid crystal display device 1 may be provided by coating a material such as silver (Ag) or titanium (Ti) on the reflective surfaces 335 and 336 of the reflector 330.

In addition, as shown in FIG. 3, the protrusion 280 may be provided in a wave shape. In this case, the protrusion 280 may be directly formed in a wave shape on the second reflection surface 336, or may be manufactured in a film type and adhered to the second reflection surface 336. Here, although the plurality of protrusions 180 are arranged to be connected to each other, of course, the diffuse reflection may be arranged to be spaced apart from each other within a range that can be efficiently.

Meanwhile, as shown in FIGS. 4 and 5, the protrusions 380 and 480 may be provided in a semicircular shape or a square shape. In this case, the protrusion 380 may be directly formed in a wave shape on the second reflective surface 336, or may be manufactured in a film type and adhered to the second reflective surface 336. Here, the protrusions 380 and 480 are arranged to be spaced apart from each other in the horizontal direction of the LEDs 321, 322 and 323, but they may be mutually arranged as shown in FIGS. 2 and 3 within a range where diffuse reflection can be efficiently performed. Of course you can.

Here, the shape or arrangement of the protrusions is not limited thereto, and the above-described prisms, waves, semicircles, and quadrangular shapes may be randomly provided on the reflective surface.

6 to 9 show a main configuration of the liquid crystal display device according to the fifth to eighth embodiments of the present invention, wherein the reflector 530 of the fifth to eighth embodiments is manufactured by press working. Is different from the first through fourth embodiments.

As shown in FIG. 6, the reflector 530 of the liquid crystal display according to the fifth exemplary embodiment of the present invention includes reflective surfaces 335 and 336 that reflect light emitted from the LED light source unit 320, and a reflective surface ( The diffuse reflection pattern 580 formed in the 336.

The reflective surface has a first reflection surface 335 on which the LED light source unit 320 is seated and one end thereof contacts the lower surface of the light control plate 310, and has an arc shape and extends upwardly from the first reflection surface 335. And a second reflecting surface 336 in contact with the upper surface of the light control plate 310.

The diffuse reflection pattern 580 is provided with a plurality of protrusions, and is formed in a portion of the second reflection surface 336. The protruding portions 580 are provided in a prism shape, and are arranged in a band shape so as to be connected to each other in the horizontal direction of the LEDs 321, 322, and 323 array directions. Here, although the plurality of protrusions 580 are arranged to be connected to each other, of course, the diffuse reflection may be arranged to be spaced apart from each other within the range that can be efficiently.

In addition, as illustrated in FIG. 7, the protrusions 680 may be provided in a wave shape, and the protrusions 680 may be disposed in a band shape and mutually connected in the horizontal direction of the LEDs 321, 322, and 323 array directions. It is. Here, although the plurality of protrusions 180 are arranged to be connected to each other, of course, the diffuse reflection may be arranged to be spaced apart from each other within a range that can be efficiently.

In addition, as shown in FIG. 8, the protrusions 780 may be provided in a hemispherical shape, and may be spaced apart in the horizontal direction in the direction of the LEDs 321, 322, and 323 arranged in a band shape. Here, the distance between the protrusions 180 is preferably such that light emitted from each of the LEDs 321, 322, and 323 is diffusely reflected and uniformly mixed. Here, the plurality of protrusions 780 are arranged to be spaced apart from each other, but of course, the diffuse reflection may be arranged in a mutually within a range that can be efficiently.

As shown in FIG. 9, the protrusions 880 may be provided in a quadrangular shape, and may be spaced apart from each other in the horizontal direction of the LEDs 321, 322, and 323 in a band shape. Here, it is preferable that the separation distance of each protrusion 880 is such that light emitted from each of the LEDs 321, 322, and 323 is diffusely reflected to be uniformly mixed. Here, although the plurality of protrusions 180 are disposed to be spaced apart from each other, it is a matter of course that the plurality of protrusions 180 may be arranged in a mutually contiguous range within which the diffuse reflection can be efficiently.

The protrusions 580, 680, 780, and 880 may be manufactured by a pressing process and may be formed by applying a predetermined physical force from the outside of the second reflective surface 336 to the inside or the inside of the outside.

In the above-described first to eighth embodiments, the diffuse reflection pattern as the protrusion is provided only in a part of the second reflection surface, but may be provided in the entire area of the second reflection surface. In addition, a diffuse reflection pattern may be provided on a part or the entire area of the first reflection surface. When the diffuse reflection pattern is formed in the entire reflector as described above, the grooves are preferably formed in both end regions of the light control plate.

10 and 11 are perspective views illustrating arrangement of an LED light source unit and a reflector in the liquid crystal display according to the ninth embodiment of the present invention.

In FIG. 10, the reflector 930 is composed of a wave shaped diffuse reflection pattern 980.

The diffuse reflection pattern 980 is provided with a plurality of protrusions, and is disposed in a direction parallel to the array direction of the LEDs 321, 322, and 323.

Protrusions 980 are formed in contact with each other are coupled to the upper and lower surfaces of the light control plate 310, wherein the upper and lower surfaces of the light control plate 310 corresponding to the shape of the protrusions 980 It is preferable that an addition is formed. In this case, the protrusion 980 may be manufactured by a pressing process and may be formed by applying a predetermined physical force toward the outside from the inside or the inside of the reference surface outside the step of forming the protrusion 980.

Here, the LEDs 321, 322, and 323 are preferably mounted at positions facing the protrusions 980. Alternatively, as illustrated in FIG. 11, the LEDs 321, 322, and 323 may be disposed to face each other between the protrusions 980. Accordingly, when the light emitted from each of the R, G, and B LEDs 321, 322, and 323 is incident between the corresponding protrusions 980 or the protrusions 980 and diffusely reflected, the liquid crystal panel 100 is uniformly mixed with white light. Since it is supplied with, the luminance is uniform and light efficiency and color reproducibility can be improved.

In the above-described ninth embodiment, the entire region of the reflector is provided in a diffuse reflection pattern, but as in the first to eighth embodiments, the diffuse reflection pattern may be formed only in the region except for the regions in contact with the upper and lower surfaces of the light control plates. Of course.

As described above, according to the present invention, there is provided a liquid crystal display device with uniform luminance and improved light efficiency and color reproducibility.

Claims (17)

A liquid crystal panel in which an image is formed; A light adjusting plate disposed at the rear of the liquid crystal panel; A light source unit provided along at least one side of the light control plate to supply light to the liquid crystal panel; And a reflector for guiding the light emitted from the light source to the light control plate and having a diffuse reflection pattern. The method of claim 1, The light source unit includes an LED light source unit having a plurality of LEDs that emit red (R), green (G), and blue (B) light, respectively. The method of claim 2, The diffuse reflection pattern may include a plurality of protrusions to uniformly mix the light emitted from each of the LEDs. The method of claim 3, The LED light source unit further includes an LED PC, the LED is arranged in a line at a predetermined interval on the LED PC, And the protrusions are formed in a band shape and are arranged to be connected to each other in a horizontal direction of the LED array direction. The method of claim 3, The LED light source unit further includes an LED PC, the LED is arranged in a line at a predetermined interval on the LED PC, And the protrusions have a band shape and are spaced apart in the horizontal direction of the LED array direction. The method according to claim 4 or 5, And the protrusion has a prism shape. The method according to claim 4 or 5, And the protrusion part has a hemispherical shape. The method according to claim 4 or 5, And the protrusion has a wave shape. The method according to claim 4 or 5, And the protrusion has a rectangular shape. The method of claim 3, And the reflector is manufactured by mold processing. The method of claim 3, And the reflector is manufactured by press working. The method of claim 3, The LED light source unit further includes an LED PC, the LED is arranged in a line at a predetermined interval on the LED PC, And the protrusion is formed in a band shape and is disposed in a direction parallel to the LED array direction. The method of claim 12, The protrusion is provided in a wave shape and disposed to face the LED. The method of claim 12, And the protrusions are provided in a wave shape, and the LEDs are disposed to face each other between the protrusions. The method of claim 2, The reflector further includes a reflective surface, wherein the diffuse reflection pattern is provided on the reflective surface. The method of claim 15, And the diffuse reflection pattern is integrally formed with the reflective surface. The method of claim 15, The diffuse reflection pattern is made of a film type, characterized in that adhered to the reflective surface.

Images