JP3872221B2 - Projection structure of LCD panel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a light projecting structure of a liquid crystal display panel incorporated in, for example, a portable information terminal.
[0002]
[Prior art]
Conventionally, in a portable information terminal, for example, a liquid crystal display panel is incorporated to display various kinds of information, and it is necessary to introduce light from the back to the panel surface. Is also built into the device.
[0003]
FIG. 3 is a cross-sectional view showing a positional relationship between a conventional liquid crystal display panel and a backlight light source. As shown in this figure, the conventional liquid crystal display panel X includes two transparent substrates 100 and 110. The liquid crystal driving unit 120 is formed by superimposing the substrates 100 and 110 while enclosing the liquid crystal LC therebetween, and one of the substrates 100 in the transparent substrate 100 on the back surface B side is transparent on the surface C side. The board 110 protrudes laterally from the entire substrate surface (the protruding portion 100a). In the protruding portion 100a, an electrode terminal (not shown) for driving the liquid crystal is drawn out from the liquid crystal driving portion 120, and the electrode terminal for driving the liquid crystal is electrically connected to a flexible wiring board or the like in the protruding portion 100a. Further, polarizing plates 130 and 140 are attached to the outer surfaces of the transparent substrates 100 and 110 so that the polarization directions of transmitted light are orthogonal to each other. The backlight source Y is a light emitting diode, for example, which is located separately from the side of the liquid crystal display panel X, and is configured to allow light to enter the liquid crystal display panel X from the side. Yes. That is, the light emitted from the backlight light source Y once wraps around the back surface B side of the liquid crystal display panel X, then reflects by a reflecting plate (not shown) and the like, and passes through the polarizing plate 130 on the back surface B side. The light advances from the back surface B side of 120 toward the front surface C side of the liquid crystal display panel X.
[0004]
[Problems to be solved by the invention]
However, according to the light projection structure of the conventional side incidence type liquid crystal display panel X, the backlight source Y is provided separately from the liquid crystal display panel X. It has been difficult to reduce the space inside the apparatus due to the arrangement space and the like. For the same reason, the conductive connection to the liquid crystal display panel X and the conductive connection to the backlight light source Y must be constructed by separate wiring forms. As the wiring form of the liquid crystal display panel X and the backlight light source Y, There was also the difficulty that a simple form could not be constructed. In addition, since the light from the backlight source Y is incident from the back surface B side of the liquid crystal display panel X through the air layer, there is a problem that the light incident efficiency with respect to the liquid crystal driving unit 120 is reduced by interface reflection.
[0005]
The present invention has been conceived under the circumstances described above, and can save space with respect to the arrangement of the liquid crystal display panel and the backlight light source, and can construct a simple form as their wiring form. At the same time, it is an object of the present invention to provide a light projecting structure for a liquid crystal display panel that can efficiently make light from a backlight light source incident on the liquid crystal display panel.
[0006]
DISCLOSURE OF THE INVENTION
In order to solve the above problems, the present invention takes the following technical means.
[0007]
In other words, the light projecting structure of the liquid crystal display panel provided by the present invention encloses the liquid crystal between two transparent substrates and superimposes both substrates, and one of the substrate surfaces of one of the substrates is the other. The liquid crystal display panel is configured such that the liquid crystal display panel protrudes laterally from the entire substrate surface, and light from the backlight light source is incident on the liquid crystal driving unit enclosing the liquid crystal by a side incidence method. A light projecting structure of a panel, wherein one of the two substrate surfaces protrudes laterally from the entire other substrate surface , and the liquid crystal driving wiring and the light source wiring are formed on the surface. When a bottomed housing recess which is entirely formed so as to fit in the backlight light source on the rear surface of the protruding portion, toward the protruding portion surface on the opposite side of the bottom surface from the bottom surface of the accommodation recess To made it is, and a through hole for conduction with the protruding portion surface which is formed on the light source wiring, the backlight source is accommodated and held in the accommodating recess wiring the light source through the through hole In the conductive state, the light from the backlight light source is configured to enter the liquid crystal driving unit of the liquid crystal display panel.
[0008]
According to the light projecting structure of the liquid crystal display panel provided by the present invention in which the above technical measures are taken, the backlight light source is housed and held in the housing recess of the protruding portion of the liquid crystal display panel. In this state, light is made incident on the liquid crystal driving unit. In other words, since the backlight light source is integrated in a state of being held in the housing recess of the liquid crystal display panel, it does not require any space for arranging the backlight light source, and space-saving such as the inside of the apparatus to which the liquid crystal display panel is mounted. Can be achieved. In addition, an electrically conductive connection between the liquid crystal driving unit of the liquid crystal display panel and the outside is established by a wiring form such as a flexible wiring board on one surface of the protruding part. On the other hand, since the electrical connection between the backlight light source and the outside is completed by electrically connecting the wiring form constructed on one side surface of the protruding portion and the through hole, the liquid crystal display panel and the backlight The conductive connection of each light source can be constructed by the same wiring form, and a simple form can be provided as the wiring form. In addition, since the light emitted from the backlight light source is guided to the liquid crystal drive unit while being directed to the inside of the one transparent substrate in which the housing concave portion is formed, the light is incident on the liquid crystal drive unit. Light is guided through a transparent substrate having excellent transparency, and light from the backlight source can be efficiently guided to the liquid crystal display panel.
[0009]
As a preferred embodiment, the outermost surface of the protruding portion farthest from the liquid crystal driving unit of the liquid crystal display panel is directed toward the back side of the liquid crystal driving unit while reflecting light from the backlight light source. It can be set as the structure by which the slope is formed.
[0010]
According to such a configuration, the light traveling from the backlight light source toward the opposite side relative to the liquid crystal driving unit is directed to the inside of the one transparent substrate in which the housing recess is formed, and the outermost surface of the protruding portion. In this way, the reflected light is directed toward the back side of the liquid crystal driving unit, so that the light from the backlight source can be efficiently guided to the liquid crystal display panel, Even with a small number of backlight sources, sufficient light can be incident on the liquid crystal display panel.
[0011]
As another preferred embodiment, on one of the transparent substrates located on the back side of the liquid crystal driving unit, the light from the backlight light source is diffused with respect to the liquid crystal driving unit. It can be set as the structure by which the rough surface is formed so that it may inject.
[0012]
According to such a configuration, light incident on the liquid crystal driving unit from the backlight light source is incident on the liquid crystal driving unit while diffusing on one of the two transparent substrates. Since it is configured, the light from the backlight source can be uniformly distributed over the entire liquid crystal driving unit, and the light from the backlight source by the side incidence method is efficiently guided to the liquid crystal display panel. be able to.
[0013]
Furthermore, as another preferred embodiment, a transparent resin can be filled in the entire interior of the housing recess with the backlight light source sealed.
[0014]
According to such a configuration, the light from the backlight light source is guided to the liquid crystal driving unit while being directed from the transparent resin filled in the entire interior of the housing recess to the inside of the transparent substrate. Because it is configured, the incident light to the liquid crystal drive unit is guided through a transparent resin and transparent substrate with excellent transparency, and the light from the backlight source is guided to the liquid crystal display panel more efficiently. Can do.
[0015]
Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.
[0017]
FIG. 1 is a cross-sectional view showing an embodiment of a light projecting structure of a liquid crystal display panel according to the present invention, and FIG. 2 is a plan view of the liquid crystal display panel shown in FIG.
[0018]
In particular, as shown well in FIG. 1, in the liquid crystal display panel A1, the liquid crystal driving unit 12 is formed by overlapping the substrates 10 and 11 while enclosing the liquid crystal LC between the two transparent substrates 10 and 11. In addition, one of the substrate surfaces of the transparent substrate 10 on the back surface B side of both the substrates 10 and 11 protrudes laterally from the entire substrate surface of the transparent substrate 11 on the surface C side (extruded portion 10a). Yes. The protruding portion 10a is formed with a housing recess 10b that can accommodate the entire backlight source A2, and the backlight source A2 is housed and held in the housing recess 10b. Furthermore, polarizing plates 13 and 14 for polarizing light from a backlight source described later are attached to the outer surfaces of the transparent substrates 10 and 11.
[0019]
On the other hand, as shown in FIG. 2, in the protruding portion 10a, the electrode terminal 15a for driving the liquid crystal LC is drawn out from the liquid crystal driving portion 12, and in the protruding portion 10a, the electrode terminal 15a for driving the liquid crystal is connected to the flexible wiring board. Conductive connection is established with A3. The backlight source A2 is electrically connected to the flexible wiring board A3 through the through hole 10c formed in the bottom surface of the housing recess 10b. The backlight source A2 is a light emitting diode (LED) made of a semiconductor chip, and the light from the backlight source A2 is reflected by a reflector or the like disposed on the back surface B side of the liquid crystal display panel A1. Thereafter, the light is guided toward the liquid crystal driving unit 12, but the backlight source A2 and the reflecting plate are configured in the same manner as in the related art, and thus detailed description thereof is omitted.
[0020]
Further, the configuration of the liquid crystal display panel A1 will be described in detail. The transparent substrates 10 and 11 positioned on the back surface B and the surface C side of the liquid crystal display panel A1 are flat plates made of, for example, glass, and the thickness thereof is a comma number. It is formed with millimeters. On the surfaces 10d and 11d where the transparent substrates 10 and 11 face each other in the liquid crystal drive unit 12, a transparent electrode pattern (not shown) for driving the liquid crystal is formed by an ITO (Indium Tin Oxide) film or the like. The transparent substrates 10 and 11 are attached to each other with the electrode surfaces 10d and 11d facing each other and the spacer 16 is sandwiched therebetween, and the liquid crystal LC is sealed in the liquid crystal driving unit 12 formed between the electrode surfaces 10d and 11d. Is done. For example, nematic liquid crystal is used as the liquid crystal LC, but cholesteric liquid crystal, smectic liquid crystal, or the like may be used. A rough surface 10e is formed by a sandblasting method or the like on an area surface facing the liquid crystal driving unit 12 on the back surface B side of the transparent substrate 10 itself so that incident light is uniformly diffused and guided over the entire liquid crystal driving unit 12. ing.
[0021]
Further, the transparent substrate 10 on the back surface B side has a protruding portion 10a having a shape in which one end of the substrate surface protrudes laterally from the transparent substrate 11 on the surface C side, and the surface C side of the protruding portion 10a The electrode terminals 15a of both transparent electrode patterns are exposed. On the other hand, on the back surface B side of the protruding portion 10a, a receiving recess 10b for receiving and holding a predetermined number of backlight light sources A2 is formed over a predetermined portion, and the protruding portion on the opposite side from the bottom of the receiving recess 10b. A through hole 10c is formed through the surface C of the portion 10a. The backlight source A2 accommodated in the accommodating recess 10b is joined to the surface C side of the protruding portion 10a through the electrode terminal 15b continuous with the through hole 10c by solidifying silver paste or the like poured into the through hole 10c. The flexible wiring board A3 is electrically connected. In this manner, the housing recess 10b in which the backlight source A2 is housed and held is filled and solidified with the transparent resin 17 having excellent light transmittance in a state where the backlight source A2 is sealed over the entire interior. Further, the outermost surface 10f of the protruding portion 10a farthest from the liquid crystal driving unit 12 is affixed with an aluminum foil or subjected to metallization processing such as aluminum deposition, and the outermost surface 10f is somewhat By forming the inclined surface toward the back surface B side, the light from the backlight light source A2 is devised so as to be directed toward the back surface B side of the liquid crystal driving unit 12.
[0022]
Each of the polarizing plates 13 and 14 is a film material in which, for example, a polymer film such as PVA (polyvinyl alcohol) is sandwiched between two TACs (tri-acetylcellulose) as a polarizer. In a state in which both the polarizing plates 13 and 14 are adhered to the transparent substrates 10 and 11, the polarization directions of the transmitted light in the both polarizing plates 13 and 14 are preferably twisted to intersect each other at a substantially right angle.
[0023]
Next, the operation of the liquid crystal display panel A1 having the above configuration will be described with reference to the drawings as appropriate.
[0024]
In the liquid crystal display panel A1 having the above-described configuration, the liquid phase state of the liquid crystal LC in the liquid crystal driving unit 12 is controlled through the flexible wiring board A3, and from the back surface B side to the front surface C side of the liquid crystal driving unit 12 shown in FIG. Then, the light from the backlight source A2 enters. The light from the backlight source A2 passes through the polarizing plate 13 on the back surface B side, and then passes through the polarizing plate 14 on the surface C side or cannot pass through depending on the liquid phase state of the liquid crystal LC. A light bright / dark pattern is formed on the surface C side of the liquid crystal display panel A1 serving as a display surface, and various kinds of information can be displayed by the light bright / dark pattern.
[0025]
Here, the optical path of the light emitted from the backlight light source A2 will be described with reference to FIG. 1. First, the light directly reaching the back surface B side of the polarizing plate 13 from the backlight light source A2 is not shown, but the polarizing plate. The light is reflected by a reflecting plate arranged immediately below 13 and then passes through the polarizing plate 13. At this time, most of the optical path from the backlight source A2 to the reflecting plate travels through the transparent resin 17 and the transparent substrate 10 in the housing recess 10b, and advances from the backlight source A2 into the space to the reflecting plate. A small amount of light is reached.
[0026]
Then, the light transmitted through the polarizing plate 13 on the back surface B side passes through the transparent substrate 10 and advances toward the transparent substrate 11 and the polarizing plate 14 on the surface C side via the liquid crystal driving unit 12. At this time, the light immediately after passing through the polarizing plate 13 on the back surface B side is incident on the rough surface 10e of the transparent substrate 10, thereby being diffused uniformly toward the surface C side of the transparent substrate 10 and the liquid crystal driving unit. 12, the light reaches the entire liquid crystal driving unit 12 uniformly. As a result, liquid crystal display can be performed with uniform brightness without causing unevenness in the periphery of the liquid crystal display surface.
[0027]
On the other hand, the light traveling from the backlight source A2 toward the opposite side relative to the liquid crystal driving unit 12 is reflected on the outermost surface 10f of the protruding portion 10a while traveling in the transparent substrate 10 on the back surface B side. The light reflected in this way goes to a reflection plate (not shown) arranged immediately below the polarizing plate 13, and then follows the same optical path as the light directly reached from the backlight source A 2 with respect to the reflection plate. . That is, the light emitted from the backlight light source A2 toward the four directions is efficiently condensed on a reflection plate (not shown) located on the back surface B side of the liquid crystal display unit 12, and is a small LED with a small amount of light. Even with the backlight light source A 2, sufficient light can be incident on the liquid crystal driving unit 12.
[0028]
That is, the liquid crystal display panel A1 employs a side incident type light projecting structure, but the liquid crystal display panel A1 is completely integrated with the side light incident type backlight light source A2. When the liquid crystal display panel A1 is incorporated into a small electronic device such as a portable information terminal, it is only necessary to wire the liquid crystal display panel A1 and one flexible wiring board A3 inside the electronic device, and the backlight source A2 There is no need to perform separate mounting and wiring processes.
[0029]
Therefore, according to the light projecting structure of the liquid crystal display panel A1 having the above configuration and operation, the backlight source A2 is housed and held in the housing recess 10b of the protruding portion 10a in the liquid crystal display panel A1. Since the light is incident on the liquid crystal driving unit 12, it is not necessary to provide an arrangement space for the backlight light source A2 separately from the liquid crystal display panel A1, and the liquid crystal display panel A1 Space-saving such as the inside of the device to be attached can be achieved.
[0030]
In addition, the electrically conductive connection between the liquid crystal driving unit 12 of the liquid crystal display panel A1 and the outside is established via the flexible wiring board A3 bonded on one surface of the protruding portion 10a, while the backlight light source A2 and Since the electrically conductive connection with the outside is also completed by conducting the same flexible wiring board A3 and the through hole 10c, the conductive connections of the liquid crystal display panel A1 and the backlight light source A2 are made according to the same wiring form. It can be built simply.
[0031]
In addition, most of the light emitted from the backlight light source A2 is guided to the liquid crystal drive unit 12 while advancing the inside of the transparent substrate 10 on the back surface B side where the housing recess 10b is formed. Therefore, the incident light to the liquid crystal driving unit 12 is guided through the transparent substrate 10 having excellent transparency such as glass, and the light from the backlight source A2 can be efficiently guided to the liquid crystal display panel A1. it can.
[0032]
In the above embodiment, the backlight light source A2 is integrated with a portion protruding from one side of the liquid crystal display panel A1, but as another embodiment, both sides of the liquid crystal display panel A1 or It is good also as a structure which formed the protrusion part over the whole circumference | surroundings and arrange | positioned backlight light source A2 in such an protrusion part.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of a light projecting structure of a liquid crystal display panel according to the present invention.
FIG. 2 is a plan view of the liquid crystal display panel shown in FIG. 1 as viewed from the front side.
FIG. 3 is a cross-sectional view showing a positional relationship between a conventional liquid crystal display panel and a backlight light source.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10,11 Transparent substrate 10a Overhang | projection part 10b Accommodating recessed part 10c Through hole 10e Rough surface 10f Outermost surface 12 Liquid crystal drive part 13,14 Polarizing plate A1 Liquid crystal display panel A2 Backlight source A3 Flexible wiring board LC Liquid crystal

Claims (4)

A liquid crystal display panel is configured in such a manner that liquid crystal is sealed between two transparent substrates and the two substrates are overlapped, and one end of one of these substrates protrudes laterally from the entire other substrate surface. And a liquid crystal display panel projecting structure configured to allow light from a backlight light source to be incident on a liquid crystal driving unit enclosing the liquid crystal by a side incidence method,
Of the above substrates, one end of one substrate surface protrudes laterally from the entire other substrate surface, and a protruding portion in which liquid crystal driving wiring and light source wiring are formed on the surface,
A bottomed housing recess which is entirely formed so as to fit in the backlight light source on the rear surface of the protruding portion,
A through hole that is formed from the bottom surface of the housing recess to the surface of the protruding portion opposite to the bottom surface, and is electrically connected to the light source wiring formed on the surface of the protruding portion ;
With
With the backlight light source housed and held in the housing recess being conducted to the light source wiring through the through-hole, the light from the backlight light source is incident on the liquid crystal driving unit of the liquid crystal display panel. A liquid crystal display panel light projecting structure characterized by comprising:   The outermost surface of the protruding portion that is farthest from the liquid crystal driving portion of the liquid crystal display panel is formed to be inclined so as to be directed toward the back side of the liquid crystal driving portion while reflecting light from the backlight light source. Item 2. A liquid crystal display panel light projecting structure according to Item 1.   On one of the transparent substrates located on the back side of the liquid crystal driving unit, a rough surface is formed so as to enter the liquid crystal driving unit while diffusing light from the backlight light source. 3. The light projecting structure for a liquid crystal display panel according to claim 1 or 2.   The light projecting structure for a liquid crystal display panel according to any one of claims 1 to 3, wherein a transparent resin is filled in the entire interior of the housing recess in a state where the backlight light source is sealed.

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