JP3661513B2 - Electro-optic device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electro-optical device that performs display using light from a backlight using an electro-optical panel such as a liquid crystal panel. More specifically, the present invention relates to a configuration of a backlight used in the electro-optical device.
[0002]
[Prior art]
In an electro-optical device using a transmissive electro-optical panel in which an electro-optical material such as liquid crystal is sandwiched between a pair of substrates, for example, display is performed by controlling the orientation state of the electro-optical material such as liquid crystal. For example, in the electro-optical device 1 illustrated in FIG. 10, a sheet-like optical component such as a lens sheet or a diffusion sheet is provided on the back side of the transmissive electro-optical panel 100 in which an electro-optical material such as liquid crystal is sandwiched between a pair of substrates. 251, a wedge-shaped light guide plate 210, and a sheet-like optical component 252 such as a reflection sheet are stacked in this order, and a light source unit 300 including a light source lamp 310 and a reflector 320 is formed on the side of the light guide plate 210. Here, the sheet-like optical components 251 and 252 are bonded and fixed to the light guide plate 210 with a double-sided adhesive tape or the like.
[0003]
Here, when the electro-optical panel 100 is configured in the TN mode, the liquid crystal 39 depends on whether an electric field is applied between the pair of substrates (the active matrix substrate 3 and the counter substrate 4) illustrated in FIG. Can be controlled for each region (pixel) in which the pixel electrode 8 is formed. In the transmissive electro-optical panel 100, light from a light source unit (not shown) is aligned with predetermined linearly polarized light by an incident-side polarizing plate 51, and then enters a layer of the liquid crystal 39. The transmitted linearly polarized light is emitted with its transmission polarization axis twisted, while the linearly polarized light that has passed through another region is emitted without its transmission polarization axis being twisted. Therefore, if the incident-side polarizing plate 51 and the outgoing-side polarizing plate 52 are arranged so that their transmission polarization axes are orthogonal to each other (normally white), the polarized light arranged on the outgoing side of the electro-optical panel 100. Only the linearly polarized light whose transmission polarization axis is twisted by the liquid crystal 39 passes through the plate 52. Therefore, arbitrary information can be displayed by controlling the alignment state of the liquid crystal 39 for each pixel.
[0004]
[Problems to be solved by the invention]
However, since the conventional electro-optical device 1 employs a structure in which the sheet-like optical components 251 and 252 are attached to the light guide plate 210 with a double-sided adhesive tape or the like, it takes time to assemble. In addition, the adhesive force of the double-sided pressure-sensitive adhesive tape is reduced by the heat generated in the light source unit 300, and the sheet-like optical components 251 and 252 are peeled off. Further, since the double-sided adhesive tape is interposed between the sheet-like optical components 251 and 252 and the light guide plate 210, there is a problem that the in-plane luminance is lowered and the light utilization efficiency is lowered. Further, as described above, since each component is bonded and fixed with a double-sided adhesive tape or the like, it is difficult to rework when a problem occurs after assembly.
[0005]
Therefore, the problem of the present invention is that in an electro-optical device using a transmissive electro-optical panel, a backlight, and a light guide plate, the sheet-like optical component can be integrated in a state of being stacked on the light guide plate without taking time, and Another object of the present invention is to provide an electro-optical device in which the sheet-like member is not peeled off from the light guide plate.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems, an electro-optical device according to the present invention is arranged so that a transmissive electro-optical panel in which an electro-optical material is sandwiched between a pair of substrates and facing one surface side of the electro-optical panel. The backlight unit includes a light guide plate having a light emitting surface directed toward the electro-optical panel, a sheet-like optical component overlaid on the light guide plate, and the light guide plate. A light source that makes light incident on the light guide plate from a side surface portion thereof, and a backlight fixing frame that collectively fixes the light guide plate and the sheet-like optical component, and the backlight fixing frame includes the light guide plate And a front frame portion that receives the outer peripheral portion on the surface side of the sheet-like optical component, and the light guide at a position excluding the side where the light source unit is disposed, around the light guide plate and the sheet-like optical component. And a side frame portion covering each outer peripheral end surface of the sheet-like optical component, and the light guide plate and the sheet-like optical component are folded from the side frame portion to the back side of the light guide plate and the sheet-like optical component. And a plurality of fixing claws that are pressed and fixed toward the portion.
[0007]
In the present invention, since the light guide plate and the sheet-like optical component are mechanically fixed together by the backlight fixing frame, the light guide plate and the sheet-like optical component are bundled together unlike the case of using the double-sided adhesive tape. The sheet-like optical component will not be peeled off even if heat from the light source is transmitted. Moreover, since it is not necessary to adhere between the light guide plate and the sheet-like optical component using a double-sided adhesive tape, it is possible to prevent a decrease in in-plane luminance and light utilization efficiency due to the presence of a double-sided adhesive tape or the like. .
[0008]
In the present invention, the fixed frame for the backlight includes the front frame portion that receives the outer peripheral portion on the surface side of the light guide plate and the sheet-like optical component, and the light source portion among the periphery of the light guide plate and the sheet-like optical component. Is folded back from the side frame portion to the back side of the light guide plate and the sheet-like optical component at a position excluding the side where the light guide plate is disposed. And a plurality of fixing claws for pressing and fixing the light guide plate and the sheet-like optical component toward the frame portion. When such a frame is used, a predetermined gap can be ensured between the optical component on the backlight unit side arranged inside the fixed frame for backlight and the polarizing plate arranged on the electro-optical panel side. Therefore, it does not damage the polarizing plate or the sheet-like optical component on the backlight unit side, and can prevent interference fringes generated when the optical component on the backlight unit side and the polarizing plate are in close contact with each other. Generation of moire caused by optical interference between the drive line of the panel and the stripe of the sheet-like optical component on the backlight unit side can also be prevented.
[0009]
In this case, the backlight fixing frame is preferably made of a metal plate. With this configuration, the heat generated in the backlight unit can be efficiently radiated to the outside of the backlight unit due to the high thermal conductivity of the metal plate. In addition, since the front frame portion and the side frame portion can be thinned, a thin and small backlight unit can be configured. In addition, since the light guide plate and the sheet-like optical component can be pressed and fixed with elasticity by the plurality of fixing claws, these components can be reliably fixed. Furthermore, light leakage from the light guide plate can be suppressed due to the high light shielding property of the metal plate.
[0010]
Further, the backlight fixing frame has at least an inner surface of the side frame portion having light reflectivity, for example, a high reflection material laminated on the inner surface of the side frame portion, or It is preferably white. If comprised in this way, since the light which is going to leak from a light-guide plate can be reflected by the inner surface of the fixed frame for backlights, the leak of the light from a light-guide plate can be suppressed. Therefore, since the amount of light emitted to the electro-optical panel can be increased, a brighter display can be performed in the electro-optical device.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings. The electro-optical panel according to the present embodiment has the same basic configuration as the electro-optical device as the electro-optical device described with reference to FIG. Will be described.
[0012]
[Overall configuration of electro-optical device]
FIG. 1 is an exploded perspective view showing the overall configuration of the electro-optical device according to the present embodiment.
[0013]
In FIG. 1, in the electro-optical device 1 of the present embodiment, a transmissive electro-optical panel 100 in which an electro-optical material such as liquid crystal is sandwiched between a pair of substrates, and a position facing the back side of the electro-optical panel 100. A sheet-like optical component 251 such as an arranged lens sheet or a diffusion sheet, a wedge-shaped light guide plate 210 in which the sheet-like optical component 251 is superimposed on the front surface side, and a reflection sheet superimposed on the back surface side of the light guide plate 210 And other sheet-like optical components 252 are arranged in this order. On the side of the light guide plate 210, a light source unit 300 including a light source lamp 310 made of a cold cathode fluorescent tube that operates at low power and has good low temperature operability, and a metal reflector 320 is configured. In the present embodiment, the light guide plate 210 is a resin molded product, and the back surface of the light guide plate 210 and the sheet-like optical component 251 are provided with a prism function in which mountain portions extend in directions orthogonal to each other.
[0014]
In the light source unit 300, wiring cables 353 and 354 are connected to both ends of the light source lamp 310 in a state where insulation is ensured by rubber holders 351 and 352, and a power source unit such as an inverter circuit 357 is connected to the wiring cable 353. Is connected.
[0015]
In this embodiment, as will be described in detail later, the sheet-like optical components 251 and 252 and the light guide plate 210 are integrated with each other by the backlight fixing frame 220, and these components are integrated as the backlight unit 200 in the electro-optical device. 1 is installed. In the backlight unit 200, the light source unit 300 is also fixed to the light guide plate 210 and is configured to be handled as a part of the backlight unit 200.
[0016]
Further, the electro-optical panel 100 and the backlight unit 200 are housed inside a pair of shield plates 151 and 152 made of a metal plate, and constitute the electro-optical device 1. Of the shield plates 151 and 152, the shield plate 152 has a box shape with a bottom. In contrast, the shield plate 151 has a frame shape, and an opening 154 that exposes the rectangular image display region 7 of the electro-optical panel 100 and a connection claw 156 used for connection to the shield plate 152 are formed. Yes.
[0017]
[Configuration of electro-optical panel]
FIG. 2 is a plan view of the electro-optical panel used in the electro-optical device according to the present embodiment as viewed from the counter substrate side. FIG. 3 is a cross-sectional view of the electro-optical panel taken along line H-H ′ in FIG. 1. FIG. 4 is a cross-sectional view of an end portion of the panel showing an active matrix substrate, a counter substrate, and a bonded structure of these substrates used in the electro-optical panel of the present embodiment.
[0018]
As shown in FIGS. 2, 3, and 4, the electro-optical panel 100 according to this embodiment includes pixel electrodes 8 made of an ITO (Indium Tin Oxide) film in a matrix on the surface of a substrate 30 such as quartz glass or heat-resistant glass. The active matrix substrate 3 is formed, the counter substrate 4 having the counter electrode 32 formed on the surface of a substrate 31 such as quartz glass or heat-resistant glass, and the liquid crystal 39 enclosed and sandwiched between these substrates. It is configured. Here, in the active matrix substrate 3, the light shielding film 9 is formed on the lower side of the region where the pixel switching TFT 10 is formed on the surface of the substrate 30, and the base protective film 5 is formed on the surface. Thereafter, the TFT 10 and the pixel electrode 8 are formed. When color display is performed using the electro-optical panel 100, a color filter is formed on the counter substrate 4 side in a region facing each pixel.
[0019]
The active matrix substrate 3 and the counter substrate 4 are bonded to each other through a predetermined gap by a gap material-containing sealing material 59 formed along the outer peripheral edge of the counter substrate 4. As a result, a liquid crystal enclosing region 40 is defined by a gap material-containing sealing material 59 between the active matrix substrate 3 and the counter substrate 4, and a liquid crystal 39 as an electro-optical material is contained in the liquid crystal enclosing region 40. It is enclosed.
[0020]
The counter substrate 4 is smaller than the active matrix substrate 3, and the peripheral portion of the active matrix substrate 3 is bonded so as to protrude from the outer peripheral edge of the counter substrate 4. Therefore, the driving circuit (scanning line driving circuit 70 and data line driving circuit 60) and the input / output terminal 45 of the active matrix substrate 3 are exposed on the outer peripheral side of the counter substrate 4. In this embodiment, the region where the drive circuit of the active matrix substrate 3 is formed is configured to be exposed to the counter substrate 4, but corresponds to the region where the drive circuit of the active matrix substrate 3 is formed. The configuration may be such that the outer peripheral edge of the counter substrate 4 is formed at substantially the same position as the outer peripheral edge of the active matrix substrate 3 and the region where the drive circuit is formed is covered with the counter substrate 4.
[0021]
Here, since the sealing material 59 is partially interrupted, the liquid crystal injection port 241 is configured by the interrupted portion. Therefore, after the counter substrate 4 and the active matrix substrate 3 are bonded together, the liquid crystal 39 can be injected under reduced pressure from the liquid crystal injection port 241 if the inner region of the sealing material 59 is in a reduced pressure state. The liquid crystal injection port 241 may be blocked with a sealant 242. Note that a light shielding film 55 is formed on the counter substrate 4 so as to cut off the display region 7 inside the region where the sealing material 59 is formed. On the counter substrate 4, a light shielding film 6 is formed in a region corresponding to the boundary region of each pixel electrode 8 of the active matrix substrate 3.
[0022]
In the electro-optical panel 100, polarizing plates 51 and 52 are provided on the surfaces of the active matrix substrate 3 and the counter substrate 4 on the light incident side and the light emitting side according to the normally white mode / normally black mode. Arranged in the direction.
[0023]
In this embodiment, the light is incident from the active matrix substrate 3 and is emitted from the counter substrate 4. Conversely, the light is incident from the counter substrate 4. Alternatively, the light may be emitted from the active matrix substrate 3.
[0024]
In the electro-optical panel 100 configured as described above, in the active matrix substrate 3, a data signal (not shown) and a display signal applied to the pixel electrode 8 through the TFT 10 cause a gap between the pixel electrode 8 and the counter electrode 32. , The alignment state of the liquid crystal 39 is controlled for each pixel, and a predetermined image corresponding to the display signal is displayed. For example, when the electro-optical panel 100 is configured in the TN mode, the rubbing direction is performed when the alignment films 46 and 49 formed between the pair of substrates (the active matrix substrate 3 and the counter substrate 4) are rubbed. Are set in directions orthogonal to each other, the liquid crystal 39 is twisted and oriented at an angle of 90 ° between the substrates. Such a twisted orientation is released by applying an electric field to the liquid crystal 39 between the substrates. Therefore, the alignment state of the liquid crystal 39 can be controlled for each region where the pixel electrode 8 is formed (for each pixel) depending on whether or not an electric field is applied between the substrates. Therefore, in the case of the transmissive electro-optical panel 100, light from a light source (not shown) is incident on the layer of the liquid crystal 39 after being aligned with predetermined linearly polarized light by the polarizing plate 51 on the incident side. The linearly polarized light that passes through a certain region is emitted with its transmission polarization axis twisted, while the linearly polarized light that has passed through another region is emitted without its transmission polarization axis being twisted. For this reason, if the incident-side polarizing plate 51 and the outgoing-side polarizing plate 52 are arranged so that their transmission polarization axes are orthogonal to each other (normally white), the polarized light arranged on the outgoing side of the electro-optical panel 100 Only the linearly polarized light whose transmission polarization axis is twisted by the liquid crystal 39 passes through the plate 52. On the other hand, if the output-side polarizing plate 52 is arranged so that the incident-side polarizing plate and the transmission polarization axis are parallel to each other (normally black), the polarized light disposed on the output side of the electro-optical panel 100. Only the linearly polarized light whose transmission polarization axis is not twisted by the liquid crystal 39 passes through the plate 52. Therefore, if these polarization states are controlled for each pixel, arbitrary information can be displayed.
[0025]
Therefore, in the active matrix substrate 3, it is necessary to supply a display signal to the pixel electrode 8 via the data line and the pixel switching TFT 10 and to apply a predetermined potential to the counter electrode 32. Therefore, in the electro-optical panel 100, a portion of the surface of the active matrix substrate 3 facing each corner portion of the counter substrate 4 is made of an aluminum film (light-shielding material) with the aid of a data line forming process. A first electrode 47 for vertical conduction is formed. On the other hand, in each corner portion of the counter substrate 4, a second electrode 48 for vertical conduction made of an ITO film (light transmissive material) is formed by using the process of forming the counter electrode 4. Further, the first electrode 47 and the second electrode 48 for vertical conduction are electrically connected by a conductive material 56 in which conductive particles such as silver powder and gold-plated fiber are mixed with an epoxy resin adhesive component. Conducted. Therefore, in the electro-optical panel 100, the active matrix substrate can be obtained by connecting the flexible wiring substrate 99 only to the active matrix substrate 3 without connecting the flexible wiring substrate or the like to each of the active matrix substrate 3 and the counter substrate 4. A predetermined signal can be input to both 3 and the counter substrate 4.
[0026]
FIG. 5 is a block diagram schematically illustrating the configuration of the electro-optical panel 100.
[0027]
As shown in FIG. 5, on the active matrix substrate 3, a pixel switching TFT 10 connected to the data line 90 and the scanning line 91, and a liquid crystal cell 94 to which a display signal is input from the data line 90 via the TFT 10. Exists. For the data line 90, a data line driving circuit 60 including a shift register 84, a level shifter 85, a video line 87, and an analog switch 86 is formed. A scanning line driving circuit 70 including a shift register 88 and a level shifter 89 is formed for the scanning line 91. In the pixel region, a storage capacitor 40 (capacitance element) is formed between the capacitor line 92 and the storage capacitor 40 has a function of improving the charge retention characteristics of the liquid crystal cell 94.
[0028]
[Configuration of Backlight Unit 200]
FIG. 6 is a perspective view of the backlight unit 200 used in the electro-optical device 1 of the present embodiment. FIG. 7 is a perspective view showing how the light source lamp 310 and the light guide plate 210 are attached to the reflector 320 in the backlight unit 200. FIG. 8 shows a state in which the light source lamp 310 and the light guide plate 210 are attached to the reflector 320, and then the light guide plate 210 and the sheet-like optical components 251 and 252 are collectively stacked by the backlight fixing frame 220 to form the backlight unit 200. FIG.
[0029]
First, in FIG. 7, the reflector 320 used in this embodiment is bent so as to surround the outer peripheral side surface of the light source lamp 310 from three sides except the light emission side of the reflector 320 by bending one metal plate. A light source mounting portion 321 and a pair of light guide plate holding portions 322 and 323 protruding from the light source mounting portion 321 toward the light emitting side of the reflector 320 are formed. Accordingly, after the reflector 320 is deformed so as to widen the gap between the light guide plate holding portions 322 and 323 and then the light source lamp 310 is inserted inside the light source mounting portion 321, as shown in FIG. The light source lamp 310 is held elastically on the outer peripheral side surface of the light source lamp 310. Next, when the thicker end portion 216 of the light guide plate 210 is inserted between the light guide plate holding portions 322 and 323 of the reflector 320, the light guide plate holding portions 322 and 323 are connected to each other as shown in FIG. The light guide plate 210 is held by sandwiching the thicker end 216 with elasticity. In this state, the light source unit 300 including the light source lamp 310 and the reflector 320 is integrated with the light guide plate 210.
[0030]
Next, as shown in FIG. 8, a backlight fixing frame 220 is prepared. The backlight fixing frame 220 is formed by, for example, pressing a single metal plate made of a tin-plated steel plate (commonly called tinplate), a copper-based material such as phosphor bronze, or an aluminum material. The front frame portion 221 having a rectangular opening 225 formed at the center, and the side extending downward from the outer peripheral edge of the front frame portion 221 corresponding to the three sides excluding the side where the light source unit 300 is located Frame portions 226, 227, and 228 and three fixing claws 229 extending downward from the respective lower end edges of the side frame portions 226, 227, and 228 are formed. Here, the side frame portions 226 and 227 are each formed in a shape corresponding to the wedge shape of the light guide plate 210.
[0031]
In this embodiment, the entire inner surface of the backlight fixing frame 220 is a metal surface (reflection surface). Alternatively, the entire inner surface of the backlight fixing frame 220 is coated with white paint. Alternatively, a highly reflective material may be laminated on the inner surface of the backlight fixing frame 220.
[0032]
In this embodiment, the front frame portion 221 of the backlight fixing frame 220 is formed with a light shielding wall 224 standing around the opening 225. The front frame portion 221 has protrusions 223 that function as spacers at four positions corresponding to the corner portions of the opening 225.
[0033]
In order to integrally superimpose the light guide plate 210 and the sheet-like optical components 251 and 252 using the backlight fixing frame 220 configured as described above, the backlight fixing frame 220 is made up of the side frame portions 226, 227 and 228. The sheet-like optical component 251, the light guide plate 210, and the sheet-like optical component 252 are stacked in this order on the portion surrounded by the side frame portions 226, 227, and 228 in this state. Thereafter, each fixing claw 229 is bent inward. As a result, the outer peripheral portions of the sheet-like optical component 251, the light guide plate 210, and the sheet-like optical component 252 are elastically pressed and fixed to the inside of the front frame portion 221 by the fixing claws 229. In this state, as shown in FIG. 6, the side frame portions 226, 227, and 228 cover the outer peripheral end surfaces of the sheet-like optical component 251, the light guide plate 210, and the sheet-like optical component 252.
[0034]
In this manner, in the state where the sheet-like optical component 251, the light guide plate 210, and the sheet-like optical component 252 are integrated by the backlight fixing frame 220 to form the backlight unit 200 shown in FIG. Is attached to the end of the light guide plate 210. Therefore, in the backlight unit 200, the sheet-like optical component 251, the light guide plate 210, and the sheet-like optical component 252 can be fixed to each other without using a double-sided adhesive tape, and the light source unit 300 is also handled as a unit. You can also.
[0035]
The backlight unit 200 configured as described above is overlapped with the electro-optical panel 100 by the shield plates 151 and 152 shown in FIG. As a result, as shown in FIG. 3, the opening 225 of the backlight fixing frame 220 overlaps the display region 7 (see FIG. 2) in a state where the electro-optical panel 100 and the backlight unit 200 are overlapped. Therefore, the light emitted from the light source lamp 310 is reflected directly or by the inner surface of the reflector 320 and enters the light guide plate 210, and is repeatedly reflected by the light guide plate 210 and passes through the sheet-like optical component 251 to be backlit. The light is emitted from the opening 225 of the fixed frame 220 to the electro-optical panel 100 and contributes to display.
[0036]
As described above, in this embodiment, the light guide plate 210 and the sheet-like optical components 251 and 252 are fixed together using the backlight fixing frame 220 instead of the double-sided adhesive tape, so the double-sided adhesive tape was used. Unlike the case, it does not take time to fix the light guide plate 210 and the sheet-like optical components 251 and 252 together, and even if heat from the light source unit 300 is transmitted, the sheet-like optical component 251, 252 is not peeled off from the light guide plate 210. In addition, since it is not necessary to bond the light guide plate 210 and the sheet-like optical components 251 and 252 using a double-sided adhesive tape, the reduction of in-plane luminance and light utilization efficiency due to the presence of the double-sided adhesive tape is prevented. can do. Furthermore, as described above, since each component is fixed without being bonded with a double-sided adhesive tape or the like, rework when a problem occurs after assembly is easy.
[0037]
Further, when the backlight fixing frame 220 of this embodiment is used, the front frame portion 221 is positioned outside the display area 7 of the electro-optical panel 100, so that the sheet-like optical element disposed inside the backlight fixing frame 220 is used. A predetermined gap (a gap corresponding to the thickness of the backlight fixing frame 220) can be secured between the component 251 and the polarizing plate 51 disposed on the electro-optical panel 100 side. Therefore, the polarizing plate 51 and the sheet-like optical component 251 are not damaged, and interference fringes and moire generated when the sheet-like optical component 251 and the polarizing plate 51 are in close contact with each other can be prevented.
[0038]
In addition, the backlight fixing frame 220 has a light reflecting metal surface, a surface coated with white paint, or a surface on which a highly reflective material is laminated on the entire inner surface or at least the inner surfaces of the side frame portions 226, 227, and 228. It has become. For this reason, light that is about to leak from the side end portion of the light guide plate 210 can be reflected by the inner surfaces of the side frame portions 226, 227, and 228 of the backlight fixing frame 220, so that light leaks from the light guide plate 210. Can be suppressed. Therefore, since the amount of light emitted to the electro-optical panel 100 can be increased, brighter display can be performed in the electro-optical device 1.
[0039]
Furthermore, in this embodiment, when the electro-optical panel 100 and the backlight unit 200 are overlapped, the light shielding wall 224 (see FIG. 8) around the display area 7 is formed in the front frame portion 221 of the backlight fixing frame 220. Reference.) Therefore, when the light emitted from the light guide plate 210 enters the electro-optical panel 100 through the opening 225 of the backlight fixing frame 210, the light does not leak to the surroundings. Therefore, in the electro-optical panel 100, the data line driving circuit 60 and the scanning line driving circuit 70 (see FIG. 2) formed around the display area 7 are not irradiated with strong light from the backlight unit 200. Therefore, since strong light is not irradiated to the driving circuit TFTs formed in the data line driving circuit 60 and the scanning line driving circuit 70, the driving formed in the data line driving circuit 60 and the scanning line driving circuit 70 is not performed. The circuit TFT does not cause malfunction due to light leakage current or the like. Therefore, the reliability of the electro-optical device 1 can be improved.
[0040]
In this embodiment, the backlight fixing frame 220 is formed of a metal plate. If comprised in this way, the heat | fever which generate | occur | produces in the backlight unit 200 can be efficiently thermally radiated outside by the high heat conductivity which a metal plate has. Further, since the front frame portion 221 and the side frame portions 226, 227, and 228 of the backlight fixing frame 220 can be thinned, a thin and small backlight unit 200 can be configured. In addition, since the light guide plate 210 and the sheet-like optical components 251 and 252 can be pressed and fixed with elasticity by the plurality of fixing claws 229, these components can be reliably fixed without being displaced. Furthermore, due to the high light-shielding property of the metal plate, light leakage from the light guide plate 210 can also be suppressed.
[0041]
Furthermore, in this embodiment, when the electro-optical panel 100 and the backlight unit 200 are overlapped, the protrusions 223 formed on the front frame portion 221 of the backlight fixing frame 220 are formed at four positions corresponding to the corner portions of the display area 7. The electro-optical panel 100 and the backlight unit 200 are only in contact with each other. For this reason, since the heat of the backlight unit 200 is not easily transmitted to the electro-optical panel 100, the heat-sensitive polarizing plate 51 is not deteriorated by the heat from the backlight unit 200. Further, the protrusion 223 is in contact with a portion in the electro-optical panel 100 where a conductive material 56 (see FIG. 2) for conducting electrical connection between the substrates is formed. It is not a region where the line drive circuit 70 is formed or a region where the polarizing plate 51 is attached. Therefore, even if the heat of the backlight unit 200 is transmitted through the protrusions 223, the data line driving circuit 60, the scanning line driving circuit 70, and the polarizing plate 51 are not deteriorated by the heat. Therefore, the reliability of the electro-optical device 1 can be improved.
[0042]
[Configuration of light guide plate]
In such a backlight type electro-optical device 1, in this embodiment, a resin plate made of acrylic resin as shown in FIG. 9 is used as the light guide plate 210. In this type of light guide plate 210, when light emitted from the light source lamp 310 and the reflector 320 of the light source unit 300 is incident on the light guide plate 210, the incident light is diffused inside the light guide plate 210 and the reflection surface 211. The light travels through the light guide plate 210 while being reflected by the light and is emitted from the light exit surface 212 through the sheet-like optical component 251 to the electro-optical panel 100 as indicated by an arrow A.
[0043]
[Other embodiments]
In the above embodiment, a liquid crystal device that is an electro-optical device using liquid crystal as an electro-optical material is taken as an example, and in particular, the present invention is applied to the active matrix type electro-optical device 1. Any type of backlight type electro-optical device 1 such as 1 can be used.
[0044]
Moreover, although the example which used the cold cathode fluorescent tube as the light source lamp 310 was shown by the said form, as a light source lamp, not only a cold cathode fluorescent tube but LED etc. may be sufficient. In this case, a plurality of LEDs can also be used.
[0045]
【The invention's effect】
As described above, in the electro-optical device according to the present invention, the backlight unit is configured by mechanically fixing the light guide plate and the sheet-like optical component together by the backlight fixing frame. Unlike the case where tape is used, it does not take time to fix the light guide plate and the sheet-like optical component together, and the sheet-like optical component is peeled off even when heat from the light source is transmitted. There is no.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing an overall configuration of an electro-optical device to which the invention is applied.
2 is a plan view of the electro-optical panel used in the electro-optical device shown in FIG. 1 when viewed from the counter substrate. FIG.
FIG. 3 is a cross-sectional view taken along the line HH ′ of FIG.
4 is an enlarged cross-sectional view of an end portion of the electro-optical panel shown in FIG.
FIG. 5 is a block diagram schematically showing the configuration of the electro-optical panel shown in FIG.
6 is a perspective view of a backlight unit used in the electro-optical device shown in FIG.
7 is a perspective view showing a state where a light source lamp and a light guide plate are attached to a reflector in the backlight unit shown in FIG. 6. FIG.
8 shows how the backlight unit shown in FIG. 6 has a light source lamp and a light guide plate attached to the reflector, and then the light guide plate and the sheet-like optical component are collectively stacked by a backlight fixing frame to form a backlight unit. It is a perspective view shown.
9A and 9B are perspective views of the light guide plate used in the backlight unit shown in FIG. 6 when viewed from the light output side, and the light guide plate from the opposite side of the light output side. It is a perspective view when seen.
FIG. 10 is an exploded perspective view showing an overall configuration of a conventional electro-optical device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Electro-optical apparatus 3 Active matrix substrate 4 Opposite substrate 6, 9, 55 Light-shielding film 7 Display area 8 Pixel electrode 39 Liquid crystal 45 Input / output terminal 51, 52 Polarizing plate 56 Conductive material 59 between substrates 59 Sealing material 60 Data line drive Circuit 70 Scanning line driving circuit 100 Electro-optical panels 151 and 152 Shield plate 200 Backlight unit 210 Light guide plate 220 Backlight fixing frame 223 Backlight fixing frame protrusion 224 Backlight fixing frame light shielding wall 225 Backlight fixing Openings 226, 227, and 228 Side frame portion 229 of fixed frame for backlight Fixed nail 251 and 252 of fixed frame for backlight Sheet-like optical component 300 Light source unit 310 Light source lamp 320 Reflector 321 Reflector light source mounting unit 322 and 323 Reflector light guide plate holder

Claims (5)

In an electro-optical device having a transmissive electro-optical panel in which an electro-optical material is sandwiched between a pair of substrates, and a backlight unit arranged to face one surface of the electro-optical panel,
The backlight unit includes a light guide plate having a light emitting surface directed toward the electro-optical panel, a sheet-like optical component overlaid on the light guide plate, and a light source that makes light incident on the light guide plate from a side surface portion of the light guide plate And a backlight fixing frame that collectively fixes the light guide plate and the sheet-like optical component,
The fixed frame for backlight includes a front frame portion that receives the outer peripheral portion on the surface side of the light guide plate and the sheet-like optical component, and the light source portion is disposed around the light guide plate and the sheet-like optical component. A side frame portion that covers the outer peripheral end surfaces of the light guide plate and the sheet-like optical component at a position other than the side where the light guide plate is located, and the light guide plate folded back from the side frame portion to the back side of the light guide plate and the sheet-like optical component. An electro-optical device comprising: a plurality of fixing claws that press and fix the sheet-like optical component toward the frame portion.   2. The electro-optical device according to claim 1, wherein the backlight fixing frame is made of a metal plate.   3. The electro-optical device according to claim 2, wherein at least an inner surface of the side frame portion of the backlight fixing frame has light reflectivity.   3. The electro-optical device according to claim 2, wherein the backlight fixing frame includes a highly reflective material laminated on at least an inner surface of the front frame portion.   3. The electro-optical device according to claim 2, wherein at least the inner surface of the side frame portion of the backlight fixing frame is white.

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