JPH0241648Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a liquid crystal display device in which a display image of a transmissive liquid crystal display panel is reflected by a reflective member surface for observation.

[Technical background of the invention]

Generally, there are two types of liquid crystal display devices that use liquid crystal display panels to perform display: reflective liquid crystal display panels with a reflective plate on the back that use external light to display images, and transmissive liquid crystal display panels. In some cases, display is performed by placing an illumination light source on the back side of the liquid crystal display panel and illuminating the liquid crystal display panel from the back side. Generally, reflective liquid crystal display panels are used for devices that are illuminated by such an illumination light source because a large amount of electric power is required to turn on the illumination light source.

However, while the reflective liquid crystal display panel can use external light such as natural light or indoor lighting for display, this reflective liquid crystal display panel reflects external light that has entered through the liquid crystal layer with a reflective plate. This method causes a large amount of light loss, resulting in a dark screen.As a result, the contrast is significantly reduced, especially in high-duty devices such as dot-matrix liquid crystal display panels. It ends up.

For this reason, recently, a transmissive type liquid crystal display panel is used as the liquid crystal display panel, and a reflective member such as a reflector is placed diagonally opposite the back surface of the transmissive type liquid crystal display panel, thereby reducing external light. It has been considered that a reflective member can be used to reflect light toward the back side of the liquid crystal display panel to display images using the front surface of the liquid crystal display panel as a screen. According to this liquid crystal display device, display can be performed using external light. However, it is a liquid crystal display device that displays images using a dot matrix display type liquid crystal display panel, because the screen can be significantly brighter than those using a reflective type liquid crystal display panel. Even if there is a problem, you can brighten the screen and display a high-contrast image.

However, in a liquid crystal display device in which the surface of the liquid crystal display panel is used as a screen by reflecting external light toward the back surface of the transmissive liquid crystal display panel using a reflective member as described above, the surface of the liquid crystal display panel also This has the problem of ambient light reflecting off the surface of the LCD panel, making it difficult to see the screen.Also, external light is reflected back toward the LCD panel using a reflective material to display the display. This also had the disadvantage that the screen would be too dark to use in places where there was insufficient outside light. Therefore, the display image of the transmissive liquid crystal display panel provided on the side of the lid body that can be opened and closed with respect to the base is configured to be reflected and observed on the reflective member surface provided on the side of the base, and inside the lid body, A removable illumination light source and its driving circuit are provided for the liquid crystal display panel,
It is conceivable to illuminate a transmissive liquid crystal display panel with external light or light from an illumination light source and reflect the transmitted light on a reflective surface.

〔Problems to be solved〕

However, if the lid is provided with a light source for illumination on the liquid crystal display panel side and its driving circuit as described above,
There was a problem in that it was difficult to miniaturize the device because the lid became large and heavy.

This idea was made in view of the above circumstances,
To provide a liquid crystal display device capable of displaying images with sufficient brightness even when there is sufficient external light and when the surroundings are dark, and capable of being miniaturized.

[Means to solve problems]

This idea includes a base having a reflective member on the top surface,
A lid body provided on the base so as to be openable and closable around one end, and a translucent window provided on the lid body;
A dot matrix display type transmissive liquid crystal display panel is provided in the lid body to face the light transmitting window, and external light entering from above the lid body through the light transmitting window is transmitted to the liquid crystal display panel. A liquid crystal display device configured to perform display using the reflective member surface as a screen by reflecting a displayed image on a panel and reflecting the displayed image on a reflective member surface on the base, wherein the liquid crystal display is provided in the lid body. A display driving circuit for driving the panel is accommodated, and an illumination light source is removably disposed facing the light incident surface side of the liquid crystal display panel, and a power supply unit and the illumination light source are driven within the base. the light source drive circuit in the base, and supplies power from a power supply section in the base to the light source drive circuit in the base and the display drive circuit in the lid, and the light source drive circuit in the base; and the illumination light source inside the lid body through the one end of the lid body, so that among the liquid crystal display panel and the illumination light source inside the lid body,
The liquid crystal display panel is driven from the lid side, and the illumination light source is driven from the base side.

[Example of idea]

An embodiment of this invention will be described below with reference to the drawings, taking a liquid crystal display type compact color television receiver as an example.

Figures 1 and 2 show the external appearance and cross section of a small color television receiver with a liquid crystal display. In the figures, 11 is the base of the television receiver, and 12 is the hood. The hood body 12 has its rear end surface pivoted to the rear end of the receiver body 11 by a support shaft 13, and is closed so as to overlap the upper surface of the receiver body 11 when not in use, and when in use, the hood body 12 is As shown in the drawings and FIG. 2, it is opened so as to stand up obliquely at a predetermined angle with respect to the upper surface of the receiver main body 11. Although not shown, the hood body 12 is locked by a locking mechanism provided on the receiver body 11 in the closed state, and is automatically opened by a spring force when the hood body locking mechanism is unlocked. It's getting old.

To explain the structure of the receiver main body 11, the receiver main body 11 has electronic components other than the liquid crystal display panel drive circuit built into a main body case 11a, and the main body case 11a has a front end side. (Opposite side to the pivot side of the hood body 12)
is formed one step higher to form an operation panel section 14, and an operation knob 15 for unlocking the hood body locking mechanism is provided on the upper surface of the operation panel section 14.

On the upper surface of the main body case 11a where the hood body 12 overlaps (excluding the operation panel section 14), there is a surface-reflection type reflector 21 as a reflective member, for example, a glass surface coated with silver vapor deposition. It is glued.

Further, a battery box 22 is formed at the bottom of the main body case 11a, and a required number of batteries 23 are accommodated in the battery box 22. In addition, 24 is the battery box 2.
This is the second lid. Further, 25 is a main body side circuit board installed in the main body case 11a, and a rod antenna 26 for receiving television radio waves and radio waves is connected to this main body side circuit board 25. This rod antenna 26 is pulled out and stretched out from the main body case 11a when in use, and is stored within the main body case 11a when not in use.

Further, a tuner 27, LSIs 28, 28, an amplification transistor 29, etc. are attached to the lower surface of the main body side circuit board 25, avoiding the position of the battery box 22, and furthermore, a front end portion of the main body side circuit board 25 is attached. In other words, an audio volume dial 30, a tuning dial, and a blind volume dial (not shown) for adjusting the image display density are attached to the upper surface of the part of the main body case 11a facing the operation panel part 14. . In addition,
In the figure, reference numeral 31 indicates an operating knob for the audio volume dial 30, and 32 and 33 indicate operating knobs for the tuning dial and bright volume dial. Further, 34 is a horizontally elongated window formed on the upper surface of the operation panel section 14, and the channel selection pointer 35 that moves in conjunction with the operation of the operation knob 32 of the tuning dial can be seen from this window 34. It's getting old. Further, on the top surface of the operation panel section 14, displays of VHF, UHF, FM, and AM stations are printed along the window section 34, and
Slide switch operation knob 36 that doubles as a power switch and a television/radio selection switch
and VHF-UHF switching slide switch 37
An operating knob 38 (see FIG. 2) and an operating knob 39 for an FM-AM switching slide switch are provided.

Further, in FIG. 2, 40 is a speaker,
This speaker 40 is mounted on a speaker mounting part 41 formed by tilting the bottom surface of the front end of the main body case 11a upward toward the front end side. is fixed with a holding member (not shown). The reason why the speaker mounting portion 41 is inclined in this manner is to emit the sound from the speaker 40 not only downward but also forward, thereby widening the range in which the sound can be heard clearly.

Next, the hood body 12 will be explained. FIG. 3 is an enlarged view of the hood body 12. This hood body 12 consists of a thin box-shaped case 12a, and the upper and lower surfaces of this case 12a are rectangular light-transmitting windows 16 and 17 are formed in the center thereof, and the upper light-transmitting window 16 is provided with a light-diffusing and transmitting plate 18 whose lower surface is made of transparent plate (for example, glass) and which has been roughened.
(hereinafter referred to as a diffuser plate) is also a transparent window 17 on the lower surface.
A display panel protective glass 19 is fitted into the display panel.

In the hood body 12, a color display is performed using a three-primary color filter in the center of which signal electrode terminals are arranged at both ends in the length direction and scanning electrode terminals are arranged at one side in the width direction. A transmissive liquid crystal display panel 44 employing a dot matrix display method is disposed between the translucent windows 16 and 17.

FIG. 4 shows the structure of a dot matrix display type liquid crystal display panel 44 that displays color using the three primary color filters.This liquid crystal display panel 44 is of a TN type (twisted nematic type). A nematic liquid crystal LC is filled between a pair of upper and lower transparent substrates 61a, 61b bonded via a sealant 60, and polarizing plates 62a, 6 are provided on the outer surfaces of the substrates 61a, 61b.
2b is glued. and the pair of 61
A, 61b, for example, on the inner surface of the upper substrate 61a, a large number of transparent scanning electrodes X are formed in parallel, and on the inner surface of the other substrate 61b, a red filter RF is formed on the surface of the transparent signal electrode Y. A red signal electrode YR, a green signal electrode YG with a green filter GF formed on the surface of the transparent signal electrode Y,
A large number of blue signal electrodes YB each having a blue filter BF formed on the surface of the transparent signal electrode Y are alternately formed in a direction perpendicular to the scanning electrodes X. In addition to the structure described above, the dot matrix display type liquid crystal display panel that displays color using three primary color filters has a structure in which the outer surface of the panel corresponds to the intersection of each scanning electrode and each signal electrode. Some are equipped with filters of various colors.

FIG. 5 is a plan view showing scanning electrodes X, X, ... and signal electrodes YR, YG, YB of each color formed on the upper and lower transparent substrates of the liquid crystal display panel 44,
In the figure, X1, X2, ...Xm are the scanning electrodes X, X,
...terminals, Y1R, Y2R, ...YnR are the terminals of the red signal electrodes YR, YR, ..., Y1G, Y2G,
. . . YnG is the terminal of the green signal electrodes YG, YG, . . . Y1B, Y2B, . . . YnB is the terminal of the blue signal electrode YB, YB, . Although a simple matrix type electrode pattern is shown here, the liquid crystal display panel 44 may be of a double matrix type.

On the other hand, in FIGS. 2 and 3, 45a, 4
Reference numeral 5b denotes a display driving circuit board disposed on both sides of the liquid crystal display panel 44 at the front end side and rear end side in the hood body 12, and these two display driving circuit boards 45a and 45b. Of these, a red driving LSI 46a is attached to the top surface of the circuit board 45a on the front end side of the hood body, and a green driving LSI 46b is attached to the bottom surface of the circuit board 45a. , the green driving circuit on the lower surface is the liquid crystal display panel 4, respectively.
Red signal electrode terminal arranged at one end of 4
Y1R, Y2R, ...YnR and green signal electrode terminal Y1G,
It is connected to Y2R, . . . YnR by film-like connectors 47a and 47b, respectively.

Furthermore, a blue driving LSI 46c is attached to the upper surface of the rear end side circuit board 45b, and a scanning driving LSI 46d is attached to the lower surface of the rear end side circuit board 45b. It is connected to the blue signal electrode terminals Y1B, Y2B, . Signal electrode terminals arranged on one side of the liquid crystal display panel 44 by a film-like connector 47d
Connected to X1, X2, ...Xm.

Further, one end of a film-like flexible connector 48 for connection with the circuit board 25 on the receiver main body 11 side is attached to the circuit board 45b portion on the rear end side of the hood body among the two circuit boards 45a and 45b. The connector 48 is pulled out from an opening 49 provided on the lower surface of the rear end of the case 12a, and pulled into the main case 11a through a slit formed on the upper surface of the rear end of the main case 11a. It is connected to the end of the main body side circuit board 25.
Note that the circuit board 45 on the front end side of this hood body 12
a, a rear end side circuit board 45b connected to the main body side circuit board 25 by the flexible connector 48;
and is connected by a cable (not shown).
It is connected to the main body circuit board 25 via this rear end circuit board 45b and the flexible connector 48.

Further, in FIGS. 2 and 3, a reference numeral 51 is provided inside the hood body 12 to face the light incident surface of the liquid crystal display panel 44, that is, the surface of the liquid crystal display panel 44 opposite to the surface facing the reflective mirror. A removably arranged electroluminescent lighting panel (hereinafter referred to as
(abbreviated as EL panel), and this EL panel 5
Reference numeral 1 denotes a knob portion 51a that is slidably supported within the hood body 12 and projects from the outer surface of the hood body.
By the sliding operation (see FIG. 1), the hood body is slid from above the liquid crystal display panel 44 to the front end side of the hood body, and is removed from above the liquid crystal display panel 44. Note that this EL panel 51 is
When this is placed facing the liquid crystal display panel 44, it is connected to the circuit board 45b on the rear end side by a contact type connector (not shown).

FIG. 6 is a block diagram showing the circuit configuration on the receiver body 11 side and the circuit configuration on the hood body 12 side. On the device body 11 side, the rod antenna 26 is connected to the tuner 27, and the tuner 2
7 is connected to a linear unit 70 constructed on the circuit board 25 on the main body side. This linear unit 70 includes a tuner power supply circuit, a tuning control circuit, a filter circuit, and a linear circuit, and the tuning control circuit sends a tuning signal to the tuner 27 in response to a signal from the tuning dial 30 shown in FIG. It is beginning to give.

Also, the tuner 27 selects the television radio waves received by the rod antenna 26 according to the tuning signal, converts it to an intermediate frequency, and outputs it to the filter circuit.The output of the filter circuit is synchronized with the video signal and audio signal in the linear circuit. The audio signal is amplified by an audio amplification circuit 71 configured on the circuit board on the main body side and sent to the speaker 40.
It is now being sent to Further, in FIG. 6, 72 is an EL panel drive circuit configured on the main body side circuit board 25.

On the other hand, in FIG. 6, 73 is a display drive circuit constructed on the circuit boards 45a and 45b on the side of the hood body 12, and this display drive circuit 73 responds to the video signal and synchronization signal from the linear unit 70. It is adapted to drive a liquid crystal display panel 44.

FIG. 7 shows the configuration of the display drive circuit 73, in which the video signal and synchronization signal from the linear unit 70 are sent to an R (red) signal A/D converter 81 and a G (green) signal A/D converter. 82,
A B (blue) signal is sent to an A/D converter 83 and a signal control circuit 84.

Further, in FIG. 7, 85 is an R signal drive circuit, 86 is a G signal drive circuit, 87 is a B signal drive circuit, and 88 is a scan drive circuit, to which a synchronization signal is input from the signal control circuit 84. , the scan drive circuit 88 is adapted to apply a drive signal to the scan electrode terminals X1, X2, . . . Further, the R signal drive circuit 85, the G signal drive circuit 86, and the B signal drive circuit 87 are connected to the R signal A/D converter 8.
1. G signal A/D converter 82, B signal A/D
By inputting a signal from the converter 83, the red signal electrode terminals Y1R, Y2R, ... YnR and the green signal electrode terminal of the liquid crystal display panel 44 are connected in accordance with the synchronizing signal.
Y1G, Y2R, ...YnR and blue signal electrode terminal Y1B,
A drive signal is given to Y2B,...YnB.

In this embodiment, the display panel drive control circuit 73 is provided on the hood body 12 side because if the display panel drive control circuit is provided on the receiver body 11 side, the receiver body 11 and the hood body 12 are connected. This is because a connector with a large number of connected lines must be used as a flexible connector, and the connection becomes extremely difficult.
If the display panel drive control circuit 73 is provided on the hood body 12 side as described above, the flexible connector 4
8 may have only a small number of lines, and the connections can be easily made.

This television receiver includes the hood body 12.
The liquid crystal display panel 4 is used with the LCD panel opened at a predetermined angle.
4 and EL panel 51 facing each other as shown by the solid line in FIG. 51 from the position facing the liquid crystal display panel 44, and move the liquid crystal display panel 44 as shown by the chain line in FIG.
The EL panel 51 is removed from above, and display is performed using outside light taken in through the diffuser plate 18. In either case, the image displayed by the liquid crystal display panel 44 is projected onto the reflecting mirror 21 diagonally facing the liquid crystal display panel 44, and is projected onto the surface of the reflecting mirror 21 as shown by the chain line in FIG. Therefore, the display image A can be viewed using the reflective mirror surface on the upper surface of the receiver main body 11 as a screen.

In this liquid crystal display type compact color television receiver, as described above, external light is received by the liquid crystal display panel 44, and the displayed image is reflected by the reflecting mirror 21 surface, and this reflecting mirror surface is used as a screen. Therefore, even if the liquid crystal display panel 44 uses three primary color filters to display color, the loss of light is much lower than when using a reflective liquid crystal display panel. Therefore, even when displaying using external light, images can be displayed with sufficient brightness and high contrast. Moreover, in this liquid crystal display type compact color television receiver, when the hood body 12 is opened as shown in FIGS. 1 and 2 and covers the upper part of the reflecting mirror 21,
Since it prevents light from hitting one side from the surroundings, the screen will not be difficult to see due to surrounding light reflecting off the reflective mirror surface. Furthermore, the liquid crystal display type compact color television receiver is provided with an EL panel 51 that is removably disposed facing the surface of the transmissive liquid crystal display panel 44 opposite to the surface facing the reflector. , even if there is not enough outside light, the EL
This can be done by placing the panel 51 opposite the liquid crystal display panel 44 and lighting up the EL panel 51.
Since the display can be performed using the illumination light of the EL panel 51, the television receiver can be used even in places where there is not enough outside light, and it can be used in places where there is enough outside light. , said
Since it is not necessary to remove the EL panel 51 from the position facing the liquid crystal display panel 44 and use the EL panel 51, it is possible to perform economical display using external light at all times.

In the liquid crystal display type compact color television receiver, a display drive circuit 7 is provided on the side of the hood body 12 that accommodates the liquid crystal display panel 44 and the EL panel 51.
3, the EL panel drive circuit 7 has large components and requires shielding to operate at high voltage.
2 is the originally large power supply unit (battery box 22).
and a battery 23), the EL panel drive circuit 7 is housed in the receiver body 11.
2 is provided on the hood body 12 side, the size can be sufficiently reduced. Also, like this
If the EL panel drive circuit 72 is housed in the receiver body 11 instead of the hood body 12, the weight of the receiver body 11, which is the base, will be sufficiently larger than the weight of the hood body 12, so that the hood body 12 cannot be raised. This also improves stability when the receiver body 11 is placed on a desk or the like.

Note that in the above embodiment, the EL panel 51 is used as a light source for illuminating the liquid crystal display panel 44;
This illumination light source may be a light emitting diode, a small fluorescent lamp, or the like.

Further, in the above embodiment, a liquid crystal display type television receiver was explained, but it goes without saying that this invention can be widely applied to liquid crystal display devices such as liquid crystal display type game consoles in addition to liquid crystal display type television receivers. be.

[Effect of idea]

As explained above, according to this invention, it is possible to use external light when the surroundings are bright, and use the illumination light source when the surroundings are dark to provide a bright display, and the lid side that can be opened and closed relative to the base Since a display drive circuit and an illumination light source are provided on the base side, and a power source and a light source drive circuit are provided on the base side having the reflecting mirror, it is possible to provide a liquid crystal display device that can be sufficiently miniaturized and has good stability. .

[Brief explanation of drawings]

Figures 1 to 7 show an embodiment of this invention, and Figures 1 and 2 are an external perspective view and a sectional view of a compact color television receiver with a liquid crystal display;
Fig. 3 is an enlarged sectional view of the hood body, Fig. 4 is an enlarged sectional view of a portion of the liquid crystal display panel, Fig. 5 is an electrode pattern diagram of the liquid crystal display panel, and Fig. 6 is a small liquid crystal display type color television receiver. FIG. 7 is a block diagram of the display driving circuit. 11...Receiver body (base), 12...Hood body (lid body), 16, 17...Transparent window, 21...Reflector, 22...Battery box, 23...Battery, 2
5... Main body side circuit board, 44... Liquid crystal display panel, 45a, 45b... Display driving circuit board, 5
1... EL panel (light source for illumination), 72... EL panel drive circuit, 73... Display drive circuit.

Claims (1)

[Claims for Utility Model Registration] A base having a reflective member on its upper surface, a lid provided to the base so that it can be opened and closed from one end, and a transparent window provided on the lid. , a dot matrix display type transmissive liquid crystal display panel provided in the lid body to face the light-transmitting window, and external light incident from above the lid body through the light-transmitting window is transmitted to the liquid crystal display panel. A liquid crystal display device configured to perform display using the reflective member surface as a screen by reflecting a displayed image on a display panel on a reflective member surface on the base, wherein the liquid crystal display is provided in the lid body. A display drive circuit for driving a display panel is accommodated, and an illumination light source is removably disposed facing a light incident surface of the liquid crystal display panel, and a power supply unit and the illumination light source are driven within the base. a light source drive circuit in the base; supplying power from a power supply unit in the base to the light source drive circuit in the base and the display drive circuit in the lid; By electrically connecting the circuit and the illumination light source in the lid body through the one end of the lid body, the liquid crystal display panel is connected to the illumination light source in the lid body. A liquid crystal display device characterized in that the light source for illumination is driven from the side of the base, and the light source for illumination is driven from the side of the base.