KR100769038B1 - Backlight Unit Manufacturing Method - Google Patents

Abstract

The present invention relates to a method of manufacturing a backlight unit.

According to an aspect of the present invention, there is provided a method of manufacturing a backlight unit, including: forming a plurality of LED grooves and electrode grooves on an upper surface of a flat lower glass; Forming an electrode pattern for supplying current to the electrode grooves through the LEDs; An LED process step fixed to the LED groove; Laminating a flat upper glass to the upper surface of the lower glass.

Description

Method for manufacturing backlight unit {Method for manufacturing backlight unit}

1 is a flow chart of a method for manufacturing a backlight unit according to an embodiment of the present invention.

2 is an exemplary view of a backlight unit for each manufacturing process according to FIG. 1;

3 is a cross-sectional view of the backlight unit manufactured according to FIG. 1.

4A is another cross-sectional view of the backlight unit manufactured according to FIG. 1.

4B is another cross-sectional view of the backlight unit manufactured according to FIG. 1.

4C is another cross-sectional view of the backlight unit manufactured according to FIG. 1.

5 is a flowchart illustrating a method of manufacturing a backlight unit according to another embodiment of the present invention.

6 is an exemplary view of a backlight unit for each manufacturing process according to FIG. 5.

7 is a cross-sectional view of the backlight unit manufactured according to FIG. 5.

8 is another cross-sectional view of the backlight unit manufactured according to FIG. 5.

9 is an illustration of a diffusion pattern.

<Explanation of symbols for main parts of the drawings>

100: lower glass 110: electrode groove

120: LED groove 200: electrode pattern

300: adhesive 400: LED

410: lead frame 420: LED chip

430 wire 440 curable resin

500: upper glass 510: LED home

600: diffusion pattern 700: reflector

The present invention relates to a method of manufacturing a backlight unit.

There are various displays of digital and media devices such as CRT, PDP, LCD, organic EL, etc., but TFT-LCD is emerging as one of the most important display types. TFT-LCDs can be largely divided into three units. The first is a panel in which liquid crystal is injected between the substrate and the second, and the second is a printed circuit board (PCB) to which a driver LSI and various circuit elements are attached to drive the panel. And as can be seen in the expression of liquid crystal, since the TFT-LCD can not emit light by itself, an external light source is essential. Therefore, it is divided into a chassis structure including a backlight that provides a light source.

Hereinafter, a backlight unit related to the present invention will be described. Light sources used in the backlight unit include fluorescent lamps, LED lamps and the like. Fluorescent lamps, especially Cold Cathode Flourscent Lamps (CCFLs), were typical as the light source for backlight units. However, as the LCD market is largely formed, there are many problems in price competitiveness and process improvement. Therefore, in recent years, LEDs having advantages such as color reproducibility, light efficiency, long life, low power consumption, light weight, and thinning have been adopted as a light source of a backlight unit.

The present applicant will propose a new method of manufacturing a backlight unit employing LED as a light source.

The present invention is derived from this background, and an object thereof is to provide a method for manufacturing a backlight unit using glass.

The above object is to form a plurality of LED grooves and electrode grooves on the upper surface of the flat bottom glass according to the present invention; Forming an electrode pattern for supplying current to the electrode grooves through the LEDs; An LED process step fixed to the LED groove; And stacking a flat upper glass on the upper surface of the lower glass. Preferably the LED process step, the step of fixing the LED chip in the LED groove; Electrically connecting the electrode pattern and the LED chip; And molding the LED chip.

In addition, the above object is to form an electrode pattern on the flat bottom glass according to the present invention; An LED process step which is fixed on the lower glass and receives light from an electrode pattern to emit light; Forming a plurality of LED grooves in the bottom surface of the flat upper glass; Stacking the upper glass on the upper surface of the lower glass, wherein the LEDs fixed on the lower glass are positioned in the LED grooves of the upper glass; Preferably the LED process step, the step of fixing the LED chip in the LED groove; Electrically connecting the electrode pattern and the LED chip; And molding the LED chip.

The foregoing and further aspects of the present invention will become more apparent through the preferred embodiments described with reference to the accompanying drawings. Hereinafter, the present invention will be described in detail to enable those skilled in the art to easily understand and reproduce the present invention.

1 is a flowchart illustrating a method of manufacturing a backlight unit according to an embodiment of the present invention, and FIG. 2 is an exemplary view of a backlight unit for each manufacturing process according to FIG. 1.

First, a plurality of LED grooves and a plurality of electrode grooves are formed on the upper surface of the flat lower glass by etching or sand blaster (step S100). Accordingly, as shown in FIG. 2A, a plurality of LED grooves 120 and a plurality of electrode grooves 110 are formed on the upper surface of the lower glass 100. Here, the depth of the LED groove 120 is preferably equal to or greater than the height of the LED to be mounted on the LED groove 120.

Next, using the printer and other equipment to form the electrode pattern 200 in the electrode groove 110 as shown in Figure 2 (b) (step S110). In one embodiment, the electrode pattern 200 is Indium Tin Oxide (ITO). However, the present invention is not limited thereto and may be other electrical materials. The electrode pattern 200 may be formed by a silk screen method or other known method. After the electrode pattern 200 is formed, the LED chip 420 is fixed to the LED groove 120, the electrode pattern 200 is electrically connected to the LED chip 420, and then the LED chip 420 is molded. The LED process manufactured by the process is performed (step S120).

Hereinafter, an embodiment of the LED process will be described with reference to FIG. 2. As is known, the LED process consists of die bonding, wire bonding, and molding. First, as shown in FIG. 2C, the lead frame 410 is positioned in the LED groove 120 and electrically connected and fixed to the electrode pattern 200. Next, as shown in (d) of FIG. 2, the LED chip 420 is fixed to the upper part of the lead frame 410 by using surface mounting technology (SMT) (Die Bonding). There are various die bonding methods, for example, an epoxy die bond method may be used. Epoxy diebonds are the most common way to bond chips to lead frames using epoxy.

After die bonding is completed, the LED chip 420 and the lead frame 410 are bonded to the wire 430 as shown in FIG. It is commonly bonded using gold wire. There are various bonding methods, for example, T / C (Thermo Compression) Bonding, T / S (Thermo Sonic) Bonding, and U / S (Ultra Sonic) Bonding. T / C Bonding is a method of bonding while heating and pressurizing, T / S Bonding is a method of bonding using sound wave energy in addition to T / C bonding, and U / S Bonding is a method of bonding with pressure and ultrasonic energy. to be. Since wire bonding itself is a known technique, detailed description thereof will be omitted.

After completion of the wire bond, for example, a molding process is performed to have a convex shape as shown in FIG. However, it is not necessarily limited to this shape. As the molding method, there are known a transfer mold method and a casting mold method. Transfer Mold is a method in which the curable resin 440 is melted with a sufficient pressure and heat by using a mold press, and a molding is applied by applying a lead frame. Casting Mold is a container having a certain shape (usually a 'molded cup in the LED process'). And a curing process by pouring the curable resin 440 using a dispenser. For example, as the curable resin, an epoxy resin is used, and as is known, a mixture of fluorescent agents may be used. The fluorescent agent may be a yttrium, aluminum, garnet-based fluorescent agent. Since molding itself is a known technique, detailed description thereof will be omitted.

As such, the LED manufacturing process is performed through die bonding, wire bonding, and molding processes directly formed on the LED groove 120 of the lower glass 100.

Hereinafter, another LED process will be described. First, the adhesive 300 is applied to the LED groove 120 with a dispenser. The LED chip 420 is attached to the adhesive and fixed to the LED groove 120 by using an SMT (Surface Mounting Technology) device. Next, the LED chip 420 and the electrode pattern 200 are electrically bonded by wire bonding. After wire bonding, the curable resin 440 is applied to the LED grooves 120 to be molded.

The difference from the LED process described above is that the lead frame is omitted, and the LED chip 420 and the electrode pattern 200 are directly wire bonded. This is not necessary to mass produce the LED itself, but is possible by including the LED manufacturing process to be used for the backlight unit in the manufacturing process of the backlight unit. Importantly, since the LED chip 420 is electrically connected to the electrode pattern 200, the lead frame 410 is not necessarily required as in the process for mass production of the LED.

When the LED manufacturing process is made through these embodiments, the LED 400 is present in each LED groove 120 as shown in FIG. The LED 400 fixed to the LED groove 120 is electrically connected to the electrode pattern 200 and emits light by receiving current from the electrode pattern 200. The LEDs 400 are connected in series in the column direction and connected in parallel in the row direction through the electrode pattern 200. However, it is not limited thereto.

Next, a flat upper glass 500 having the same size as the lower glass 100 is laminated on the upper surface of the lower glass 100 as shown in FIG. 2H (step S150). That is, the upper glass 500 and the lower glass 100 are bonded to each other. Since the technique of bonding glass itself is well known, a detailed description thereof will be omitted.

Meanwhile, the method of manufacturing a backlight unit according to the present invention may further include the following process in addition to the above process.

First, to form a diffusion pattern on the upper surface of the upper glass 500 (step S130). The diffusion pattern is preferably formed on the same vertical line as the LED 400 of the lower glass 100. The diffusion pattern serves to diffuse light emitted from the LED 400 and may have a shape as shown in FIGS. 9A, 9B, and 9C to perform this role. A diffusion pattern having a shape as shown in FIGS. 9A, 9B, and 9C may be formed on the upper surface of the upper glass 500 by etching, sand blaster, or the like.

Secondly, the lower surface of the upper glass 500 is formed in the light guide plate structure (step S140). By doing so, the light emitted from the LEDs 400 may be uniformly dispersed. Embodiments of forming the light guide plate structure of the lower surface of the upper glass 500 are various, which will be described later.

Third, to form a reflective layer by applying a reflective material on the lower surface of the lower glass 100 (step S160). Some of the light emitted from the LED 400 and emitted from the upper glass 500 having the above-described light guiding structure is emitted to the opposite side to generate a loss. Therefore, in order to re-inject the lost light into the upper glass 500, a reflective material having excellent reflectance is applied to the lower surface of the lower glass 100. The reflective material here may be silver chloride (AgCl), but the reflective material itself is irrelevant to the subject matter of the present invention.

In another embodiment, the lower glass 100 is stacked on a reflector made of a metal to form a reflective layer (step S160). In this case, the reflector is preferably a metal material having high reflection effect and high thermal conductivity, and may be, for example, aluminum. Preferably, the upper surface of the reflector in contact with the lower surface of the lower glass 100 is smoothly processed into a flat plate to improve the reflection efficiency.

3 is a cross-sectional view of the backlight unit manufactured according to FIG. 1.

’ 형상의 반사체(700) 상에 끼워져 고정된다.Although the lower glass 100 is flat, it is not easy to check the cross-sectional view, but a plurality of electrode grooves 110 and a plurality of LED grooves 120 are formed on the upper surface of the lower glass 100. For example, ITO is applied to the electrode groove 110 to form an electrode pattern 200, and the LED groove 120 is electrically connected to the electrode pattern 200 to emit light by a current supplied from the electrode pattern 200. LED 400 is fixed. In one embodiment, a lower surface of the lower glass 100 is coated with a reflective material to form a reflective layer, or as shown in another embodiment, the lower glass 100 may be stacked on the reflector 700. In the latter case the lower glass 100 is in one embodiment '

It is fitted on the reflector 700 of the 'shape is fixed.

On the other hand, the upper glass 500 is also flat, stacked on the upper surface of the lower glass 100 to form an integral with the lower glass 100.

4A, 4B and 4C are further cross-sectional views of the backlight unit manufactured according to FIG. 1.

’ 형상의 반사체(700) 상에 끼워져 고정된다.Although the lower glass 100 is flat, it is not easy to check the cross-sectional view, but a plurality of electrode grooves 110 and a plurality of LED grooves 120 are formed on the upper surface of the lower glass 100. For example, ITO is applied to the electrode groove 110 to form an electrode pattern 200, and the LED groove 120 is electrically connected to the electrode pattern 200 to emit light by a current supplied from the electrode pattern 200. LED 400 is fixed. In one embodiment, a lower surface of the lower glass 100 may be coated with a reflective material to form a reflective layer, or as shown in another embodiment, the lower glass 100 may be stacked on the reflector 700. In the latter case, in one embodiment the lower glass 100 is'

It is fitted on the reflector 700 of the 'shape is fixed.

The upper glass 500 is a flat plate, the bottom surface is formed in various shapes as shown in Figures 4a, 4b, 4c. 4A, 4B, and 4C are principles using optical characteristics, for example, FIG. 4A illustrates the LEDs 400 by processing the lower surface of the upper glass 500 in a form in which the LED 400 emitting surface is offset, that is, in an offset form. It serves as a light guide plate to uniformly disperse the light emitted from. 4B and 4C also have a bottom surface of the upper glass 500 processed to serve as a light guide plate to uniformly disperse the light emitted from the LEDs 400. Here, glass processing is possible by the above-mentioned etching or sandblasting method.

5 is a flowchart illustrating a method of manufacturing a backlight unit according to another embodiment of the present invention, and FIG. 6 is a view illustrating a backlight unit for each manufacturing process according to FIG. 5.

First, a plurality of electrode patterns 200 are formed on the upper surface of the flat lower glass 100 as shown in FIG. 6A using a printer and other equipment (step S500). As described above, after forming the plurality of electrode grooves as described above, the electrode pattern 200 may be formed in the electrode groove. The electrode pattern 200 may be indium tin oxide (ITO). The electrode pattern 200 may be formed by a known silk screen method.

After the electrode pattern 200 is formed, a manufacturing process of the LED 400 electrically connected to the electrode pattern 200 is processed (step S510). As is known, the LED process consists of die bonding, wire bonding, and molding. First, as shown in FIG. 6B, the lead frame 410 is electrically connected to and fixed to the electrode pattern 200. Next, as illustrated in FIG. 6C, the LED chip 420 is fixed to the upper part of the lead frame 410 by using surface mounting technology (SMT) (Die Bonding). There are various die bonding methods, for example, an epoxy die bond method may be used. Epoxy Die Bond is the most common method of bonding chips to lead frames using epoxy.

After die bonding is completed, the LED chip 420 and the lead frame 410 are bonded to the wire 430 as shown in FIG. It is commonly bonded using gold wire. There are various bonding methods, for example, T / C (Thermo Compression) Bonding, T / S (Thermo Sonic) Bonding, and U / S (Ultra Sonic) Bonding. T / C Bonding is a method of bonding while heating and pressurizing, T / S Bonding is a method of bonding using sound wave energy in addition to T / C bonding, and U / S Bonding is a method of bonding with pressure and ultrasonic energy. to be. Since wire bonding itself is a known technique, detailed description thereof will be omitted.

After completion of the wire bond, for example, a molding process is performed to have a convex shape as shown in FIG. However, it is not necessarily limited to this shape. As is known, molding methods include a transfer mold method and a casting mold method. Transfer Mold is a method that melts the curable resin 440 with sufficient pressure and heat by using a Mold Press, and then applies molding by processing a lead frame. Casting Mold is a container having a certain shape (usually 'molding in the LED process). The curable resin 440 is poured into a cup using a dispenser, thereby molding. For example, as the curable resin, an epoxy resin is used, and as is known, a mixture of fluorescent agents may be used. The fluorescent agent may be a yttrium, aluminum, garnet-based fluorescent agent. Since molding itself is a known technique, detailed description thereof will be omitted.

As such, the LED manufacturing process is performed through die bonding, wire bonding, and molding.

Hereinafter, another LED process will be described. First, an adhesive is applied to the LED mounting position on the lower glass 100 with a dispenser. And using the Surface Mounting Technology (SMT) equipment to bond the LED chip 420 to the adhesive to be fixed on the lower glass (100). Next, the LED chip 420 and the electrode pattern 200 are electrically bonded by wire bonding. After wire bonding, the curable resin 440 is coated on the LED chip 420 to be molded.

The difference from the LED process described above is that the lead frame is omitted, and the LED chip 420 and the electrode pattern 200 are directly wire bonded. This is not necessary to mass produce the LED itself, but is possible by including the LED manufacturing process to be used for the backlight unit in the manufacturing process of the backlight unit. Importantly, since the LED chip 420 is electrically connected to the electrode pattern 200, the lead frame 410 is not necessarily required as in the process for mass-producing LEDs.

When the LED manufacturing process is performed through these embodiments, the LED 400 is electrically connected to the electrode pattern 200 as shown in FIG. 6F, and receives light from the electrode pattern 200. The LEDs 400 are connected in series in the column direction and connected in parallel in the row direction through the electrode pattern 200. However, it is not limited thereto.

Meanwhile, a plurality of LED grooves 510 are formed on the bottom surface of the flat upper glass 500 by etching or sand blaster, as shown in FIG. 6G (step S520). The depth of the LED groove 510 is preferably equal to or greater than the height of the LED 400 to be inserted into the LED groove 510. Next, as illustrated in FIG. 6 (h), the upper glass 500 is stacked on the lower glass 100, but the LEDs 400 fixed on the lower glass 100 are led to the LED groove 120 of the upper glass 500. The layers are stacked so as to be respectively inserted into the fields (step S550). The upper glass 500 is integrated with the lower glass 100 to be integrated, and the technology for bonding the glass itself is well known and thus a detailed description thereof will be omitted.

On the other hand, the backlight unit manufacturing method according to the present invention may further include the following process in addition to the above process.

First, to form a diffusion pattern on the upper surface of the upper glass 500 (step S530). The diffusion pattern is preferably formed on the same vertical line as the LED 400 of the lower glass 100. The diffusion pattern serves to diffuse light emitted from the LED 400 and may have a shape as shown in FIGS. 9A, 9B, and 9C to perform this role. A diffusion pattern having a shape as shown in FIGS. 9A, 9B, and 9C may be formed on the upper surface of the upper glass 500 by etching, sand blaster, or the like.

Secondly, the bottom surface of the LED groove 510 is formed in the light guide plate structure so that light emitted from the LEDs 400 may be uniformly distributed (step S540). An embodiment of forming the lower surface of the upper glass 500 in the light guide plate structure will be described later.

Third, to form a reflective layer by applying a reflective material on the lower surface of the lower glass 100 (step S560). Some of the light emitted from the LED 400 and emitted from the upper glass 500 having the above-described light guiding structure is emitted to the opposite side to generate a loss. Therefore, in order to re-inject the lost light into the upper glass 500, a reflective material having excellent reflectance is applied to the lower surface of the lower glass 100. The reflective material here may be silver chloride (AgCl), but the reflective material itself is irrelevant to the subject matter of the present invention.

In another embodiment, the lower glass 100 is stacked on a reflector made of a metal to form a reflective layer (step S560). In this case, the reflector is preferably a metal material having high reflection effect and high thermal conductivity, and may be, for example, aluminum. Preferably, the upper surface of the reflector in contact with the lower surface of the lower glass 100 is smoothly processed into a flat plate to improve the reflection efficiency.

7 is a cross-sectional view of the backlight unit manufactured according to FIG. 5.

’ 형상의 반사체(700) 상에 끼워져 고정된다.The lower glass 100 has a flat plate shape, and an upper surface thereof has a plurality of electrode patterns 200 and an LED 400 electrically connected to the electrode pattern 200 to emit light by a current supplied from the electrode pattern 200. Is fixed. In one embodiment, a lower surface of the lower glass 100 is coated with a reflective material to form a reflective layer, or as shown in another embodiment, the lower glass 100 may be stacked on the reflector 700. In the latter case, in one embodiment the lower glass 100 is'

It is fitted on the reflector 700 of the 'shape is fixed.

Although the upper glass 500 is flat, it is not easy to check the cross-sectional view, but a plurality of LED grooves 510 are formed on the lower surface of the upper glass 500. The upper glass 500 is stacked on the upper surface of the lower glass 100 to be integrated with the lower glass 100, and the LEDs 400 are stacked in each of the LED grooves 510.

8 is another cross-sectional view of the backlight unit manufactured according to FIG. 5.

’ 형상의 반사체(700) 상에 끼워져 고정된다.The lower glass 100 has a flat plate shape, and an upper surface thereof has a plurality of electrode patterns 200 and an LED 400 electrically connected to the electrode pattern 200 to emit light by a current supplied from the electrode pattern 200. Is fixed. In one embodiment, a lower surface of the lower glass 100 is coated with a reflective material to form a reflective layer, or as shown in another embodiment, the lower glass 100 may be stacked on the reflector 700. In the latter case the lower glass 100 is in one embodiment '

It is fitted on the reflector 700 of the 'shape is fixed.

The upper glass 500 is flat, but a plurality of LED grooves 510 are formed on the bottom surface thereof. The upper glass 500 is stacked on the upper surface of the lower glass 100 to be integrated with the lower glass 100, and the LEDs 400 are stacked in each of the LED grooves 510. And the bottom surface of the LED groove 510 is formed to be rounded in the upper direction, as shown, to serve as a light guide plate to uniformly distribute the light emitted from the LED (400).

As described above, the present invention achieves a backlight unit using glass and a method of manufacturing the same. And the present invention is to process the glass, for example, to facilitate the process such as etching (sand blaster). In addition, the structure of placing the LED in the LED groove, it is possible to slim the backlight unit.

In addition, since the LED process is included in the backlight manufacturing process, there is no need to secure mass-produced LEDs.

In addition, since a single reflector creates a reflection effect as well as a heat dissipation effect, the backlight unit can be made slimmer.

On the other hand, the present invention has been described with reference to the embodiments shown in the drawings, which are merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention should be defined only by the appended claims.

Claims (12)

delete Forming a plurality of LED grooves and electrode grooves on an upper surface of the flat lower glass; Forming an electrode pattern for supplying current to the electrode grooves through the LEDs; Manufacturing an LED to be fixed to the LED groove, including fixing the LED chip to the LED groove, electrically connecting the electrode pattern and the LED chip, and molding the LED chip after the electrical connection; Stacking a flat upper glass on the upper surface of the lower glass; Backlight unit manufacturing method comprising a. The method of claim 2, Forming a diffusion pattern on the upper surface of the upper glass to diffuse the light emitted from the LED; Back light unit manufacturing method characterized in that it further comprises. The method of claim 2, further comprising: forming a light guide plate structure on a lower surface of the upper glass so that light emitted from the LED is uniformly dispersed; Back light unit manufacturing method characterized in that it further comprises. The method according to any one of claims 2 to 4, Forming a reflective layer on the lower glass; Back light unit manufacturing method characterized in that it further comprises. The method of claim 5, wherein the reflective layer is a metal material having high thermal conductivity. delete Forming an electrode pattern on the flat lower glass; Fixing the LED chip to the LED mounting positions on the lower glass, electrically connecting the electrode pattern and the LED chip, and molding the LED chip after the electrical connection to be fixed to the LED mounting positions. Manufacturing the leds; Forming a plurality of LED grooves in the bottom surface of the flat upper glass; Stacking the upper glass on the upper surface of the lower glass, wherein the LED fixed on the lower glass is positioned in the LED groove of the upper glass; Backlight unit manufacturing method comprising a. The method of claim 8, Forming a diffusion pattern on the upper surface of the upper glass to diffuse the light emitted from the LED; Back light unit manufacturing method characterized in that it further comprises. The method of claim 8, further comprising: forming a light guide plate structure on the bottom surface of the LED groove so that light emitted from the LED is uniformly dispersed; Back light unit manufacturing method characterized in that it further comprises. The method according to any one of claims 8 to 10, Forming a reflective layer on the lower glass; Back light unit manufacturing method characterized in that it further comprises. 12. The method of claim 11, wherein the reflective layer is a metal material having high thermal conductivity.

Images