KR20080079839A - Apparatus of manufacturing brightness enhancing sheet and method of the same - Google Patents

Abstract

A method and an apparatus of manufacturing a brightness enhancement sheet are provided to apply two-dimensional optical properties to the brightness enhancement sheet by refracting an incident beam in two dimensions. An apparatus of manufacturing a brightness enhancement sheet includes a resin supply unit(300), a lens shape former(310), and a light irradiator(320). The resin supply unit applies a photocuring resin on a lens supporting unit. The lens shape former engraves plural lens units on a surface of the photocuring resin. The light irradiator cures the photocuring resin having the plural lens units thereon. The lens units have the same shape and circumscribe one another. The lens units form fly-eye-lenses, which form rows and columns on the lens supporting unit.

Description

Apparatus and method for manufacturing a brightness enhancement sheet {APPARATUS OF MANUFACTURING BRIGHTNESS ENHANCING SHEET AND METHOD OF THE SAME}

1 is a perspective view of a prism sheet used in a conventional backlight unit.

2 is a perspective view illustrating a configuration of a liquid crystal display device according to an exemplary embodiment of the present invention.

3 is a perspective view of a brightness improving sheet using a fly-eye lens according to an exemplary embodiment of the present invention.

4A is a plan view of the luminance improving sheet of FIG. 3.

4B is a front view of the luminance improving sheet of FIG. 3.

5 is a view schematically showing an apparatus and method for manufacturing a brightness improving sheet according to an embodiment of the present invention.

6 is a perspective view illustrating a molding process of the roller of FIG. 5.

7 is a perspective view illustrating a method of manufacturing the lens-shaped portion of the brightness improving sheet according to the embodiment of the present invention.

The present invention relates to an apparatus and method for manufacturing a brightness enhancement sheet, and more particularly, to an apparatus and method for manufacturing a brightness enhancement sheet that saves time and cost and enables mass production.

In general, a liquid crystal display device (hereinafter referred to as an LCD device) converts various electrical information generated by various devices into visual information by using a change in liquid crystal transmittance according to an applied voltage. It is an electronic device.

Since the LCD device is a display device for various information and does not have a self-luminous source, it requires a separate device that illuminates the entire screen of the LCD device by placing a light source on the back of the LCD device. (Back Light Unit).

1 is a perspective view of a prism sheet used in a conventional backlight unit.

Referring to FIG. 1, a conventional prism sheet 10 includes a prism support 12 and a plurality of prism features 14 formed side by side over the entire surface on the prism support 12. The prism shape 14 has a side portion consisting of a first face 18 and a second face 17 and forms a substantially isosceles triangle when viewed from the front. The first surface 18 and the second surface 17 generally form an angle of 90 °, but may be configured differently according to a selection.

A plurality of prismatic features 14 are formed continuously on the prism support 12 to alternately form the valleys 16 and the peaks 15. The prism sheet 10 configured as described above refracts light incident on the prism support part 12 while passing through the prism shape part 14. As a result, light incident at a low angle is concentrated toward the front, thereby increasing luminance in the effective viewing angle range.

However, the prism-shaped portion 14 of the conventional prism sheet 10 has a problem in that its side surface is flat and refracts incident light only in one direction, which is not suitable for refracting light in two dimensions.

SUMMARY OF THE INVENTION An object of the present invention is to provide a manufacturing apparatus and method capable of manufacturing a sheet by a simpler method than in the prior art in manufacturing a brightness improving sheet capable of improving the refractive performance of light.

Still another object of the present invention is to provide an apparatus and method for manufacturing a brightness enhancing sheet which can reduce time and cost in the manufacturing process and enable mass production.

An apparatus for manufacturing a brightness enhancement sheet according to the present invention includes a resin supply unit for applying a photocurable resin on a lens support, a lens shape manufacturing unit for embossing a plurality of lens units on a surface of the photocurable resin, and the plurality of It characterized in that the lens unit comprises a light irradiation unit for curing by irradiating light to the photocurable resin formed by embossing.

In addition, the manufacturing method of the brightness improving sheet according to the present invention, the step of applying a photocurable resin on the lens support, the lens support to which the photocurable resin is applied through a plurality of lens units formed intaglio through the roller Forming a lens-shaped portion formed by embossing the two lens units, and curing the lens-shaped portion by irradiating light capable of curing the photocurable resin.

By the manufacturing apparatus and method of the said brightness improving sheet, the brightness improving sheet which can improve the refractive performance of light by a comparatively simple method can be manufactured.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the apparatus and method for manufacturing a brightness enhancement sheet according to the present invention.

2 is a perspective view illustrating a configuration of a liquid crystal display device according to an exemplary embodiment of the present invention. 3 is a perspective view of a brightness improving sheet using a fly-eye lens according to an exemplary embodiment of the present invention, FIG. 4A is a plan view of the brightness improving sheet of FIG. 3, and FIG. 4B is a brightness improving sheet of FIG. 3. Front view.

2, the liquid crystal display device 100 of the present invention, the liquid crystal panel 110 for illuminating the liquid crystal panel 110 and the liquid crystal panel 110 for displaying an image according to a drive signal and a data signal applied from the outside It includes a backlight unit 120 disposed on the back of the.

The backlight unit 120 is located at the rear of the liquid crystal panel 110 and provides light, for example, white light, to the liquid crystal panel 110.

The backlight unit 120 has a light source, for example, a cold cathode fluorescent lamp (hereinafter referred to as a "CCFL") in accordance with the installation method of the lamp is positioned below the liquid crystal panel and the lamp is a light guide plate There is an edge-light method located on the side.

The backlight unit 100 of FIG. 2 is an edge-light method backlight unit and includes a light source unit 122, a light guide plate 124, a reflective sheet 126, and an optical film 128.

The light source unit 122 includes one or more light sources 122a and a light source reflector 122b.

The light source 122a generates light having a predetermined wavelength.

The light generated from the light source 122a is incident through the light guide plate 124. The light source reflector 122b reflects the light generated from the light source 122a toward the light guide plate 124 to allow the light incident to the light guide plate 124. Improve the efficiency.

The reflective sheet 126 reflects the light, which is generated by the light source 122a and proceeds to the rear surface of the light guide plate 124, that is not incident to the light guide plate 124 toward the light guide plate 124. The light guide plate 124 causes the light to travel toward the liquid crystal panel 110.

The optical film 128 includes a diffusion sheet 128a, a brightness enhancement sheet 128b, and a protective sheet 128c.

Light emitted from the light guide plate 124 toward the liquid crystal panel 110 passes through the diffusion sheet 128a. The diffusion sheet 128a disperses the light incident from the light guide plate 124 to prevent the light from being partially concentrated. And make the luminance uniform.

The light passing through the diffusion sheet 128a is sharply lowered in brightness, and the brightness enhancement sheet 128b is used to prevent this.

The brightness enhancing sheet 128b of the present invention is characterized by using fly-eye-lens.

Fly-eye-lens is mainly used to adjust the beam shape of light, and because it can increase the quality of parallel light, it has the function of equalizing the brightness of the screen when used as a project part. do. Recently, the demand is gradually increasing as a means to replace the existing prism sheet in the projection TV and the backlight unit.

More specifically, referring to FIG. 3, the brightness enhancement sheet 128b includes a lens support portion 220 including a lens support portion 210 and a plurality of lens units 220a formed on the front surface of the lens support portion 210. Include.

The lens unit 220a has a hemispherical shape and protrudes embossed on the lens support 210. The plurality of lens units 220a circumscribe each other as shown in FIGS. 4A and 4B to form rows and columns. It is arranged on the lens support 210.

As shown in FIG. 4A, the lens unit 220a may have a circular shape in plan view, but may not necessarily have a circular shape and may have an elliptical shape.

The light passing through the brightness enhancing sheet 128b by the plurality of lens units 220a is refracted in two dimensions, thereby improving light performance.

5 is a view schematically showing an apparatus and method for manufacturing a brightness improving sheet according to an embodiment of the present invention.

Referring to FIG. 5, the apparatus for manufacturing a brightness improving sheet according to an exemplary embodiment of the present invention includes a resin supply unit 300, a lens shape manufacturing unit 310, and a light irradiation unit 320.

First, the lens support portion 210 rotates in a rolled state, and one end thereof is continuously supplied into the manufacturing apparatus.

The lens support 210 is an optical film, and is preferably made of a thermoplastic polymer film that is transparent, flexible, and excellent in processability.

When the lens support part 210 is supplied into the manufacturing apparatus, the resin supply part 300 applies the photocurable resin 222 to the lens support part 210 in a predetermined thickness.

When the resin supply part 300 supplies a predetermined amount of the photocurable resin 222 on the lens support part 210, the photocurable resin 222 is dispersed on the surface of the lens support part 210 so as to be coated with a predetermined thickness. do.

Subsequently, the lens support part 210 to which the photocurable resin 222 is applied moves to the lens shape manufacturing part 310.

The lens shape manufacturing unit 310 includes a roller 312 that rotates in a predetermined direction and a fixing part 314 that fixes the roller 312 thereon.

A plurality of grooves are formed in an intaglio form on the outer surface of the longitudinal cylinder of the roller 312, and both ends of the rotating shaft of the roller 312 are fixed to the upper portion by the fixing part 314.

6 is a perspective view illustrating a molding process of the roller of FIG. 5.

Referring to FIG. 6, the roller 312 may include a roller rotating part 316 for rotating the roller 312 in a longitudinal axis, and a bite that vibrates up and down with a predetermined period and contacts the rotating outer surface of the roller 312. , 318).

First, the roller rotator 316 rotates the roller 312 at a constant speed along the longitudinal axis by driving power. The bite 318 starts the up and down movement at regular intervals with the longitudinal end of the roller 312, for example, located at the left end, as shown in FIG. 6. Here, the vertical movement width of the bite 318 depends on the thickness of the groove 220b of the lens unit to be formed in the roller 312.

One end of the cross section in contact with the roller 312 of the bite 318 may have various shapes, but according to one embodiment for forming the fly-eye-lens, the cross section has a circular or elliptical shape.

When the bite 318 reaches the lowest point of vertical vibration, the outer surface of the roller 312 is formed with a groove 220b corresponding to one end of the bite 318 in contact. Since the bite 318 vibrates up and down at a constant cycle, and the roller 312 rotates at a constant speed, a plurality of grooves 220b are repeatedly formed around the roller 312 on the outer surface of the roller 312.

Then, when one row of grooves 220b are all formed along the outer surface of the roller 312, the bite 318 moves to the right by a predetermined length. By repeating this process, the grooves 220b may be formed in a predetermined pattern on the outer surface of the roller 312.

On the other hand, the vertical vibration frequency of the bite 318 affects the shape of the groove 220b formed on the outer surface of the roller 312. The lower the frequency, the longer the contact time of the bite 318 in contact with the outer surface of the roller 312, so that the groove 220b formed has a long oval shape. According to a preferred embodiment of the present invention, the vertical vibration frequency of the byte 318 is in the range of 1 kHz to 50 kHz, more preferably 5 kHz to 20 kHz.

According to another embodiment of the present invention, as described above, one bite 318 does not move from side to side in the longitudinal direction of the roller 312, but the plurality of bites 318 are the length of the roller 312. The grooves 220b may be formed in the roller 312 at the same time in a row.

7 is a perspective view illustrating a method of manufacturing the lens-shaped portion of the brightness improving sheet according to the embodiment of the present invention.

Referring to FIG. 7, when the lens support part 210 coated with the photocurable resin 222 passes through the roller 312 rotating in a predetermined direction, a groove formed in the roller 312 may be formed on the surface of the photocurable resin 222. In response to the shape of 220b, a lens shape part 220 having embossed lens units 220a is formed.

According to an embodiment of the present invention, the individual lens unit 220a has a hemispherical shape or an elliptic hemispherical shape, and the plurality of lens units 220a form a row and a column on the lens support while circumscribing each other in a fly-eye lens. (fly-eye-lens).

As the size of the lens unit 220a increases, the light collecting ability is improved, but the thickness of the finished sheet increases, so that the lens unit 220a needs to have an appropriate size. According to a preferred embodiment of the present invention, the diameter or long axis of the lens unit 220a is in the range of 1 μm to 1 mm, more preferably in the range of several μm to several hundred μm.

Referring to FIG. 5 again, the lens shape part 220 including the plurality of lens units 220a is formed in the photocurable resin 222 that has passed through the lens shape manufacturing part 310.

Subsequently, the lens shape part 220 in which the plurality of lens units 220a are formed moves to the light irradiation part 320.

The light irradiation part 320 irradiates the light curable resin 222 to the photocurable resin 222 for a predetermined time, for example, an ultraviolet ray (UV) that can harden the photocurable resin 222, thereby curing the lens shape part 220.

As such, the brightness enhancement sheet 128b having the fly-eye-lens-shaped lens shape 220 formed on the lens support 210 may be selectively covered with the protective films 330a and 330b on the upper and lower surfaces thereof. After rougher, the manufacturing process is completed by being wound around the brightness improving sheet winding roll.

Preferred embodiments of the present invention described above are disclosed for purposes of illustration, and those skilled in the art having ordinary knowledge of the present invention will be able to make various modifications, changes, additions within the spirit and scope of the present invention, such modifications, changes and Additions should be considered to be within the scope of the following claims.

According to the manufacturing apparatus and method of the brightness improving sheet which concerns on this invention, the brightness improving sheet which can improve the refractive performance of light by a simple method compared with the past can be manufactured.

In addition, by manufacturing the brightness enhancement sheet by the molding method, it is possible to reduce the time and cost in the manufacturing process and to mass production.

The brightness enhancing sheet produced by the manufacturing apparatus and method according to the present invention has two-dimensional optical performance improved compared to the conventional brightness improving sheet because the incident light is refracted in two dimensions.

Claims (12)

A resin supply unit for applying a photocurable resin on the lens support unit; A lens shape manufacturing unit for embossing a plurality of lens units on a surface of the photocurable resin; And And a light irradiation part for curing the photocurable resin formed by embossing the plurality of lens units. The method of claim 1, And the plurality of lens units have the same shape and circumscribe each other to form fly-eye-lens by forming rows and columns on the lens support. The method of claim 1, The manufacturing apparatus further includes a roller forming unit, the roller forming unit, A roller rotating part for rotating the cylindrical roller in the longitudinal axis; And And a bite which vibrates up and down with a constant frequency and contacts the rotating outer surface of the cylindrical roller to engrave the plurality of lens units in a negative manner. The method of claim 3, wherein The frequency is in the range of 1 kHz to 50 kHz, characterized in that the manufacturing apparatus of the brightness improving sheet. The method of claim 1, The lens unit is a device for producing a brightness enhancement sheet, characterized in that the diameter or major axis is hemispherical or elliptic hemispherical in the range of 1 ㎛ to 1 mm. The method of claim 1, And a protective film attaching part for attaching a protective film on the cured brightness improving sheet passing through the light irradiation part. (a) applying a photocurable resin on the lens support; (b) forming a lens shape by passing a roller having a plurality of lens units engraved on the photocurable resin; And and (c) irradiating the photocurable resin with light to cure the lens-shaped portion. The method of claim 7, wherein the lens portion, A fly-eye-lens shape, characterized in that the manufacturing method of the brightness enhancement sheet. The method of claim 7, wherein step (b), (b-1) rotating the cylindrical roller along the longitudinal axis; And (b-2) forming a roller by forming a plurality of lens units in an intaglio manner on the outer surface of the cylindrical roller while a bite vibrating up and down with a constant frequency contacts the rotating outer surface of the cylindrical roller; The manufacturing method of the brightness improvement sheet characterized by including further. The method of claim 9, The frequency is in the range of 1 kHz to 50 kHz. The method of claim 7, wherein The lens unit is a method of manufacturing a brightness enhancement sheet, characterized in that the diameter or major axis is hemispherical or elliptic hemispherical in the range of 1 ㎛ to 1 mm. The method of claim 7, wherein The method of manufacturing a brightness enhancement sheet further comprising the step of attaching a protective film on the brightness enhancement sheet subjected to the step (c).

Images