JPH08184821A - Display device - Google Patents

Abstract

PURPOSE: To provide a display device constituted so that the information quantity which can be displayed is increased while the portability thereof is secured. CONSTITUTION: The display surface of the flat type display device 17 using a light emission type element which a shaft 18 as a turning center is freely turnably supported on the side opposite to the surface 9 of the liquid crystal display device 16. The device 16 is provided with the surface 9 which can be viewed as a reflection type and a surface 8 which can be viewed as a transmission type. Therefore, two display devices of the display device 17 and the surface 9 of the display device 16 can be separately utilized in an opened state. On the other hand, only the surface 8 of the display device 16 is viewed in a closed state. By using the display light emission of the both-surface display device as a back light, the display 20 of the light emission type display device 17 and the display 19 of the liquid crystal display device 16 are synthesized and displayed on the display surface 8 of the both-surface display device 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device, and more particularly to a display device for displaying information and functions used in electronic equipment such as a portable information terminal.

[0002]

2. Description of the Related Art Conventionally, the incident light from one surface is reflected,
As a display means capable of double-sided display that transmits incident light from the other surface, a means other than attaching two display devices is a reflective liquid crystal display device in which the reflector is removed, and both surfaces are transmissive. There is a liquid crystal display device that can be seen as.

Further, as an opening / closing interlocking type double-sided display device,
A liquid crystal display device disclosed in JP-A-5-150233 is known. In the liquid crystal display device, the opening / closing mechanism of the display unit and the moving mechanism of the reflecting plate are interlocked with each other, so that the reflecting plate on the side that touches the display surface as seen from the user can be removed so that it can be used, and the function is provided on the back surface. There are two types of methods for installing a reflector plate in.

As a first method, the roller rotates in conjunction with the rotation of the fixed shaft that constitutes the hinge structure of the display unit when opening and closing, and the sheet with the reflection plate is moved from one side of the liquid crystal to the other side. There has been proposed a method in which a mechanism for feeding to a surface is provided so that the reflector is always removed from the display surface on the user side and the reflector is positioned on the back surface.

As a second method, opening / closing reflectors are installed on both sides of the liquid crystal display panel, and the reflectors on the display surface side are erected so as to be vertical in cooperation with the opening / closing mechanism of the display unit. A method is proposed in which the reflector on the back side is closed so that only one of them functions as a reflector.

Conventionally, when information is displayed on a certain plane, one display panel is installed on the plane and used. In the display device having the two openable display surfaces described above, two display panels are used in an open state.

[0007]

In the case of the conventional double-sided display device, since there is no auxiliary light source for ensuring the visibility on both sides, the background on the back surface of the panel is affected and a clear display cannot be obtained.

In order to avoid this problem, it is necessary to install a reflector or a backlight on both sides, and if these are provided, the scale of the device becomes large and it is difficult to miniaturize it.

In the case of the liquid crystal display device disclosed in Japanese Unexamined Patent Publication No. 5-150233, a mechanism having complicated movable parts is required, and the above-mentioned second method requires a space for a standing reflector. Therefore, there are restrictions on miniaturization and portability. In addition, in the second method that uses a large number of movable parts, an unreasonable force may be applied to the standing reflector from the outside. Therefore, in order to ensure reliability and durability, cost reduction is attempted. It is difficult.

Further, in the case of a flat panel display device, since the information that can be displayed is determined by the area of the plane, the amount of information is limited when it is used to display a small electronic device such as a wrist watch or a portable information terminal. On the other hand, in the case of a display device having two openable and closable display surfaces, the amount of information that can be displayed is almost twice as large as when there is only one display panel, but the display cannot be seen in the closed state. It must be kept open at all times, which limits its portability when used.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a display device capable of increasing the amount of displayable information while ensuring portability.

[0012]

According to the present invention, the aforementioned object is to provide a display device having a liquid crystal display element having a polarizing plate on the surface thereof, and having an optical filter arranged on the polarizing plate. In order to enable display on both front and back sides,
The display device according to claim 1, wherein a surface of the optical filter in contact with the polarizing plate transmits a part of incident light and reflects the other part, and the other surface absorbs the incident light. It

According to the present invention, the above object is to provide a double-sided display device having a liquid crystal display element for displaying an image as a reflection type on one surface and a transmission type for the other surface, and a light emitting element. And a flat display device having a flat display device, wherein the flat display device is openably and closably supported so that the display surface faces the one surface of the liquid crystal display device. This is achieved by a display device according to claim 2.

According to the invention, the above object is achieved by a display device according to claim 3, characterized in that the double-sided display device is the display device according to claim 1.

According to the present invention, the above-described object is to provide a liquid crystal display device having a backlight, wherein the flat display device is provided with a liquid crystal display device and a double-sided display device. The display device according to claim 4, wherein the polarization directions of the polarizing plates are the same.

According to the present invention, the aforementioned object is increased and opened in a state where the brightness of the light emitting element of the flat display device is closed in association with the opening and closing of the double-sided display device and the flat display device. The display device according to claim 5, further comprising a brightness changing unit for changing the brightness so as to decrease the brightness in the state.

According to the present invention, the above-mentioned object has a structure in which the double-sided display device and the flat display device are opened and closed in the vertical direction with respect to the display direction. The display device according to claim 6, further comprising image inverting means for displaying a normal image on the double-sided display device in a closed state.

According to the present invention, the above-mentioned object has a structure in which the double-sided display device and the flat display device are opened and closed laterally with respect to the display direction. The display device according to claim 7, further comprising image inverting means for displaying a normal image on the double-sided display device in a closed state.

According to the present invention, the aforementioned object is achieved by a display device according to claim 8, further comprising a pen tablet for performing pen input.

According to the present invention, for the above-mentioned purpose, the pen tablet is configured to read a state of a display surface to detect an input position, and the pen tablet is the double-sided display device and the flat display device. It is achieved by the display device according to claim 9, wherein the display device is configured to perform pen input with respect to.

[0021]

In the display device according to the first aspect, the optical filter absorbs the incident light from one surface, transmits a part of the incident light from the other surface, and reflects most of the remaining light. It As a result, the liquid crystal display device can see the display as a transmissive type in which the contrast is obtained by the light incident from the back side from the surface side provided with the optical filter,
The display can be seen as a reflection type in which the contrast is obtained by reflecting the incident light from the front side from the side without the filter.

In the display device according to the second aspect, an image is displayed on each of the double-sided display device and the flat-panel display device in the open state, and displayed on the double-sided display device and the flat-panel display device in the closed state. The images are combined and displayed. Thus, in the closed state, the light emission of the light emitting flat panel display device can be used as a backlight and can be used as one transmissive liquid crystal display device. At this time, the light-emitting flat panel display is not allowed to emit light entirely, but is kept in the information display state, so that the display on the flat panel display and the display on the double-sided display appear to overlap with each other, and the display is apparently combined. .

In the display device according to the third aspect, an image is displayed on each of the double-sided display device and the flat-panel display device in the open state, and displayed on the double-sided display device and the flat-panel display device in the closed state. The images are combined and displayed.

In the display device according to the fourth aspect, the polarization directions of the polarizing plates on the overlapping surfaces of the double-sided display device and the liquid crystal display device having a backlight are the same. As a result, the display in the closed state can minimize the reduction of transmitted light due to passing through the liquid crystal panel twice.

In the display device according to the fifth aspect, the brightness changing means increases the emission brightness so as to increase the contrast of the composite screen in the closed state, and balances the contrast with the double-sided display device in the open state. The emission brightness is reduced as if it were taken. As a result, a sufficient amount of transmitted light can be secured in the closed state, and in the open state, the difference in contrast between the double-sided display device and the flat display device is reduced, and a display that is easy to see is obtained and at the same time, power consumption is reduced. It

In the display device according to the sixth aspect, when the double-sided display device and the flat-panel display device are closed by the image inversion means, the image displayed on the double-sided display device is vertically mirror-inverted. As a result, it is possible to display an image according to the state of use by the user.

In the display device according to the seventh aspect, when the double-sided display device and the flat-panel display device are closed by the image inversion means, the image displayed on the double-sided display device is mirror-inverted with respect to the left and right. As a result, it is possible to display an image according to the state of use by the user.

In the display device according to claim 8, pen input can be performed with a pen tablet, and when the double-sided display device and the flat display device are used in an open state, while referring to the display of one display device, The display can be input and edited on the other display device.

In the display device according to the ninth aspect, pen input can be performed on both the double-sided display device and the flat-panel display device by a pen tablet, and the double-sided display is performed when the double-sided display device and the flat-panel display device are closed. Pen input is possible only on the device. This makes it possible to input / edit the display on the other display device while referring to the display on one display device when using the device with the device open, and to use the pen input when the device is closed. -The target of editing work is switched to a double-sided display device that can be directly instructed with a pen.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the display device of the present invention will be described below with reference to the drawings.

As shown in FIG. 2, the display device of this embodiment has a liquid crystal layer 12 sandwiched between glass substrates 11 and 13 on which transparent electrodes are arranged as a liquid crystal display device. Polarizing plates 10 and 14 having different polarization directions are arranged on both sides of 13, respectively. And
An optical filter 15 having a high transmittance and a low reflectance characteristic and ensuring the strength of the entire device is disposed in close contact with the polarizing plate 14, and the polarizing plate 10 is further provided with incident light from one surface. The optical filter 1 that absorbs the incident light from the other surface and transmits a part of the incident light from the other surface, and reflects the remaining most part, polarizes the one surface that absorbs the incident light outward and the other surface that reflects and transmits the light. It is arranged so as to be in close contact with the plate 10.

The optical filter 1 is, as shown in FIG.
Most of the light 2 incident from the one surface 7 becomes the reflected light 3,
Part of the light passes through the other surface 8 as transmitted light 4, and the light 5 incident from the surface 8 is scattered and absorbed in the filter 1 as shown by an arrow 6, and is hardly emitted to both surfaces 7 and 8. There is.

Next, the operation of this embodiment will be described.

The light incident from the surface 9 is filtered by the filter 15,
The light passes through the polarizing plate 14, the glass substrate 13, the liquid crystal layer 12, the glass substrate 11, and the polarizing plate 10, and reaches the filter 1. Since the filter 1 has the above-mentioned characteristics, most of the light is reflected by the surface 7 and exits from the surface 9 again. At this time, part of the light passes through the surface 8 as transmitted light. Further, the light incident from the surface 8 is absorbed by the characteristics of the filter 1 and does not escape from both surfaces of 8 and 9. Therefore, in the liquid crystal display device of this embodiment, the user can
When viewed from above, the filter 1 functions as a reflective liquid crystal display device that functions as a reflection plate, and when viewed from the surface 8 by the user, functions as a transmissive liquid crystal display device that uses light incident from the surface 9 as a light source. To do.

A second embodiment of the display device of the present invention will be described below with reference to the drawings.

As shown in FIGS. 2 and 3, the display device of the present embodiment has a liquid crystal display device 16 capable of displaying on both front and back sides as a double-sided display device having the same configuration as that of the first embodiment described above. In addition, the liquid crystal display device 16 is rotatably supported on the side where the display surface of a flat display device 17 as a flat display device using a light emitting element having a shaft 18 as a rotation center faces. Has been done. As the flat panel display device 17, an EL panel, a plasma display, a liquid crystal display panel with a backlight, an LED panel, or the like that performs display by contrast between a light emitting portion and a non-light emitting portion is used.

Next, the operation of this embodiment will be described.

When the liquid crystal display device 16 and the display device 17 are in an open state as shown in FIG. 3, the user can see the light emitting type display device 17 and the double-sided display liquid crystal display device 16 as a reflective type. One will see the surface 9 and the two displays can be used separately.

On the other hand, when the liquid crystal display device 16 and the display device 17 are in the closed state as shown in FIG. 4, only the surface 8 of the double-sided display liquid crystal display device 16 which can be seen as a transmission type is seen. The display surface of the light emitting display device 17 is hidden behind the back surface of the double-sided display device 16. By using the display emission of this double-sided display device as a backlight,
On the display surface 8 of the double-sided display device 16, a light-emitting display device 17 is provided.
And the display 19 of the liquid crystal display device 16 are combined and displayed.

A third embodiment of the display device of the present invention will be described below with reference to the drawings.

The display device of this embodiment has the same structure as that of the second embodiment, and a liquid crystal display device with a backlight 17 is used as a flat display device using the light emitting element shown in FIG. ing.

The liquid crystal display device 16 is, as shown in FIG.
It has a liquid crystal layer 12 sandwiched between glass substrates 11 and 13 on which transparent electrodes are arranged.
Polarizing plates 10 and 14 having different polarization directions on both sides of
Is provided. The polarizing plate 14 has a high transmittance and a low reflectance characteristic, and an optical filter 15 for ensuring the strength of the entire device is closely arranged, and the polarizing plate 10 has one surface. The optical filter 1 which absorbs the incident light from the other side and transmits a part of the incident light from the other side and reflects the remaining most of the light is outwardly reflected and transmitted through the one side which absorbs the incident light. The other surface is arranged so as to be in close contact with the polarizing plate 10. Similarly, the liquid crystal display device 17 with a backlight has a glass substrate 3 on which transparent electrodes are arranged.
It has a liquid crystal layer 31 sandwiched by 0 and 32, and polarizing plates 29 and 33 having different changing directions are arranged on both sides of the glass substrates 30 and 31, respectively. An optical filter 28 for surface protection having a high transmittance and a low reflectance is closely arranged on the polarizing plate 29, and a backlight 34 is arranged outside the polarizing plate 33.
Then, as shown in FIG. 7, the polarization direction 35 of the polarizing plate 14 of the liquid crystal display device 16 and the liquid crystal display device 1 with a backlight.
The polarization direction 36 of the polarizing plate 29 of No. 7 is the same.

The polarizing plates 14 and 29 are, as shown in FIG.
The incident light 22 polarized in the predetermined direction 35 is transmitted, but the incident light 23 polarized in the orthogonal direction 26 is not transmitted.

Next, the operation of this embodiment will be described.

When the liquid crystal display device 16 and the liquid crystal display device 17 with a backlight are closed as shown in FIG.
Since the transmitted light from the backlight 34 of the liquid crystal display device 17 with a backlight is polarized in the direction of arrow 36, almost all of it passes through the polarizing plate 14 on the surface 9 of the double-sided liquid crystal display device which is polarized in the direction of arrow 35. Therefore, it is possible to minimize the reduction of transmitted light caused by passing through the liquid crystal panel twice, and efficiently use the light from the backlight 34.

A fourth embodiment of the display device of the present invention will be described below with reference to the drawings. The basic configuration of the display device of this embodiment is the same as that of the display device shown in FIGS.

In the display device of the present embodiment, as shown in FIG. 8, the double-sided liquid crystal display device 16 and the light-emitting display device 17 are provided on the surface 9 of the double-sided liquid crystal display device 16 that overlaps the light-emitting display device 17. A micro switch 39 as a mechanism for detecting opening / closing is installed near the shaft 18 in order to avoid accidental touching by the user.

The microswitch 39 is shown in FIG.
As shown in FIG.
Brightness dimming circuit 4 as brightness changing means for adjusting the brightness of the
0 is connected, and the flatness display device drive circuit 50 is connected to the brightness dimming circuit 40.

Next, the operation of this embodiment will be described.

Double-sided liquid crystal display device 16 and emissive display device 1
As shown in FIG. 4, when 7 and 7 are closed, the micro switch 39 is turned on, and the brightness dimming circuit 40 has L level.
The ow signal is input, the brightness dimming circuit 40 does not function, and the light emitting element drive power input to the brightness dimming circuit 40 is output to the light emitting element 41 as it is, and the light emitting element 41 emits light with the highest brightness. In addition, as shown in FIG. 3, when the double-sided liquid crystal display device 16 and the light emitting display device 17 are in the open state, the micro switch 39 is in the OFF state, and the dimming circuit 40.
A high signal is input to the light control circuit 40, the light control circuit 40 functions, the light emitting element drive power input to the light control circuit 40 is adjusted and output to the light emitting element 41, and the light emitting element 41 is in a state where the brightness is reduced. Emits light.

Therefore, in the display device of the present embodiment, in the closed state, the luminance of the light emission of the light emitting type display device 17 which is reduced by passing through the liquid crystal display device 16 is compensated for, and the display device of the two display devices 16 and 17 is supplemented. The contrast of the composite displays 19 and 20 can be increased, and in the open state, the contrast of the display 20 of the light emitting display device 17 is lowered, and the display 19 of the double-sided display device 16 functioning as a reflective liquid crystal panel is displayed. The difference in the contrast between and is reduced, a display that is easy for the user to see can be obtained, and power can be saved by reducing the output.

The microswitch 39 is provided on the display surface of the light-emitting display device 17 or the shaft 18 serving as a fulcrum for opening and closing.
May be provided.

A fifth embodiment of the display device of the present invention will be described below with reference to the drawings. The basic configuration of the display device of this embodiment is the same as that of the display device shown in FIGS.

In the display device of this embodiment, as shown in FIG. 8, the double-sided liquid crystal display device 16 and the light-emitting display device 17 are provided on the surface 9 of the double-sided liquid crystal display device 16 on the side overlapping with the light-emitting display device 17. A micro switch 39 as a mechanism for detecting opening / closing is installed near the shaft 18 in order to avoid accidental touching by the user.

The microswitch 39 is shown in FIG.
As shown in FIG. 3, the double-sided liquid crystal display device 16 is connected to the scanning direction control input (DIR) 43 of the scanning line electrode drive circuit 42 as the image inverting means. A data signal electrode drive circuit 44 is connected to the double-sided liquid crystal display device 16.

Next, the operation of this embodiment will be described.

Double-sided liquid crystal display device 16 and emissive display device 1
7, the micro switch 39 remains OFF in the open state as shown in FIG. 3, and the scanning direction control input (DIR) 43 of the scanning line electrode drive circuit 42 is set to High.
The signal of h is input, and the scanning direction is L1, L
2 ,. ． ． ． , Ln, which is a normal image when viewed from the direction of arrow 37. Further, as shown in FIG. 4, when the double-sided liquid crystal display device 16 and the light emitting display device 17 are closed,
The micro switch 39 is turned on, a Low signal is input to the scanning direction control input (DIR) 43 of the scanning line electrode drive circuit 42 of the double-sided liquid crystal display device 16, and the scanning directions Ln ,. ． ． , L2, L1 and arrow 3
It becomes a normal image when viewed from the direction of 7. That is, assuming that a part of the display of the double-sided display device is as shown in FIG. 11A when the display device is open, if the display device is closed when the scanning direction is not controlled. , Fig. 11
Although the display is as shown in FIG. 11B, by performing the above control, the display as shown in FIG. 11C can be performed and a normal image can be obtained when viewed in the direction of the arrow 37.

It should be noted that the display device having the above-described structure is not a vertically inverted mirror image display like the display 19 of FIG. 4 with respect to the display 19 of FIG. Orthogonal image for, ie display 1 in FIG.
It is possible to display the display 38 shown in FIG.

In this embodiment, the display device which opens and closes vertically has been described as an example, but even when the opening and closing directions are different, it is necessary to invert the mirror image in accordance with the viewing direction of the user, so that the display device is opened and closed left and right. In the case of a display device, it is necessary to have a function of inverting the direction of a signal input to the data signal electrode drive circuit so as to perform mirror image inversion to the left and right.

A sixth embodiment of the display device of the present invention will be described below with reference to the drawings. The basic configuration of the display device of this embodiment is the same as that of the display device shown in FIGS.

In the display device of this embodiment, as shown in FIG. 3, the liquid crystal display device 16 has a backlit liquid crystal display device 17 supported so as to be openable and closable about a shaft 18 as a rotation center. As shown in FIG. 13, the liquid crystal display device 16 has a liquid crystal layer 12 sandwiched between glass substrates 11 and 13 on which transparent electrodes are arranged.
Polarizing plates 10 with different changing directions on both sides of 13,
14 are provided. An optical filter 15 having a high transmittance and a low reflectance characteristic and ensuring the strength of the entire device is disposed in close contact with the polarizing plate 14, and the polarizing plate 10 is provided with one surface. An optical filter 1 that absorbs incident light and transmits a part of the incident light from the other surface, and reflects most of the remaining light, has one surface that absorbs the incident light outward and reflects and transmits the other surface. Are arranged so as to be in close contact with the polarizing plate 10. Similarly, the liquid crystal display device 17 with a backlight has a glass substrate 3 on which transparent electrodes are arranged.
It has a liquid crystal layer 31 sandwiched by 0 and 32, and polarizing plates 29 and 33 having different changing directions are arranged on both sides of the glass substrates 30 and 31, respectively. An optical filter 28 for surface protection having a high transmittance and a low reflectance is closely arranged on the polarizing plate 29, and a backlight 34 is arranged outside the polarizing plate 33.
The changing direction 3 of the polarizing plate 14 of the liquid crystal display device 16
5 and the polarization direction 36 of the polarizing plate 29 of the liquid crystal display device 17 with a backlight coincide with each other. Furthermore, optical filter 2
A transparent pen tablet 45 for pen input is disposed on the surface side of the liquid crystal display device 16 facing the liquid crystal display device 16. There are two types of pen tablet 45: one that operates in a state independent of the display on the display device and then has software or circuit processing to open the display, and one that directly reads the display state with a pen. In the case of a tablet having two types and independent formats, as shown in FIG. 3, with the display device opened, the display of the double-sided display device 16 is referred to while the display of the light-emitting display device 17 is displayed. It is possible to perform input / edit work.

As shown in FIG. 14, an arithmetic processing circuit 51 for specifying the position supported by the pen is connected to the backlit liquid crystal display device 17 and the pen tablet 45.

When a pen tablet of the type in which the display state is directly read by the pen is used, since the tablet is driven in a synchronized state by taking in the scanning state of the display device, the data signal electrodes of the light emitting flat panel display device 17 are used. , By using the state of each defeat circuit of the scan line electrode as the input of the tablet, as in the case of using the above independent tablet,
With reference to the display of the double-sided display device 16, it becomes possible to perform an input / editing operation on the display of the light emitting display device 17.

A display device incorporating a circuit as shown in FIG. 15 will be described.

A scanning information control circuit 47 is connected to the double-sided display device 16 and the flat panel display device 17 as a control means for controlling the pen tablet drive circuit 48 based on the scanning information, and the scanning information control circuit 47 is connected to the scanning information control circuit 47. NAND circuit 5
2 is connected. The manual switch 46 is connected to one input of the NAND circuit 52, and a signal is input to the other input by software.

Therefore, the user turns on the manual switch 46.
Or the signal from the software is Low
In this case, the input signal S to the scanning information control circuit 47 becomes High, and the scanning information of the light emitting display device 17 is output to the pen tablet driving circuit 48. When the user turns off the manual switch 46 and the signal from the software becomes HI, the input signal S to the scanning information control circuit 47 becomes Low, and the pen tablet drive circuit 48.
The scanning information of the double-sided display device 16 is output to. In the display device configured as described above, pen input / edit work is performed on both the double-sided display device 16 and the light-emitting display device 17 by manual switching by the user's manual switch 46 or software control. Will be possible.

The seventh embodiment of the display device of the present invention will be described below with reference to the drawings. The basic configuration of the display device of this embodiment is the same as that of the display device shown in FIGS.

In the display device of this embodiment, as shown in FIG. 8, the double-sided liquid crystal display device 16 and the light-emitting display device 17 are provided on the surface 9 of the double-sided liquid crystal display device 16 which is on the side overlapping with the light-emitting display device 17. A micro switch 39 as a mechanism for detecting opening / closing is installed near the shaft 18 in order to avoid accidental touching by the user.

As shown in FIG. 16, an AND circuit 53 is connected to the micro switch 39, and a NAND circuit 52 is connected to the other input of the AND circuit 53. The manual switch 46 is connected to one input of the NAND circuit 52, and a signal is input to the other input by software. Further, to the output side of the AND circuit 53, a scanning information control circuit 47 that controls the pen tablet drive circuit 48 based on scanning information from the double-sided display device 16 and the flat display device 17 is connected.

Next, the operation of this embodiment will be described.

When the display device is opened as shown in FIG. 3, the micro switch 39 is in the OFF state, and the scanning information of the double-sided display device 16 and the light-emitting display device 17 is controlled by the control circuit depending on the state of the manual switch 46 and the software. It is switched by 47 and output to the pen tablet drive circuit 48. When the display device is closed, the micro switch 39 is turned on, the input signal S to the scanning information control circuit 47 becomes Low regardless of the states of the manual switch 46 and the software, and the scanning information of the double-sided display device 16 becomes pen-shaped. It is output to the tablet drive circuit 48.

As described above, in the display device of this embodiment, pen input / editing work can be performed on both the double-sided display device 16 and the light-emitting display device 17 when the display device is open. In the closed state, the pen input / editing work can be performed only on the double-sided display device 16 that can be directly touched by the pen.

[0073]

According to the display device of the first aspect, the display can be seen from the side provided with the optical filter as a transmissive type in which contrast is obtained by the light incident from the back surface,
From the side without the filter, the display can be seen as a reflection type in which contrast is obtained by reflection of incident light from the front. As a result, the degree of freedom in installation can be improved without requiring a complicated structure or mechanism.

According to the display device of claim 2, when it is opened, it can be used as a display device having a two-layer structure of a light-emitting flat display device and a reflective liquid crystal display device, and when it is closed, It can be used as one transmissive liquid crystal display device using the light emission of the light emitting flat display device as a backlight. As a result, when closed, a display amount equivalent to that of a conventional display device can be secured without impairing portability, and when opened, the display area is doubled and a backlight is provided. Can be omitted,
The cost can be reduced.

According to the display device of claim 3, when it is opened, it can be used as a display device having a two-layer structure of a light-emitting flat display device and a reflective liquid crystal display device, and when it is closed, It can be used as one transmissive liquid crystal display device using the light emission of the light emitting flat display device as a backlight. As a result, when closed, a display amount equivalent to that of a conventional display device can be secured without impairing portability, and when opened, the display area is doubled and a backlight is provided. Can be omitted,
The cost can be reduced.

According to the display device of the fourth aspect, in the display in the closed state, the reduction of the transmitted light due to passing twice through the liquid crystal panel can be minimized. As a result, it is possible to both secure the light source for obtaining high-quality display and reduce the power consumption.

According to the display device of the fifth aspect, a sufficient amount of transmitted light can be secured in the closed state, and in the open state, the difference in contrast between the liquid crystal display device and the light emitting display device is reduced, and the display is easy to see. At the same time, the power consumption can be reduced.

According to the display device of the sixth aspect, it is possible to display an image according to the state of use by the user. This eliminates the troublesomeness of the user consciously adjusting and inverting the display, and eliminates the need for the user to manually perform the display reversing switch, so that another function can be provided in the newly created space.

According to the display device of the seventh aspect, it is possible to display an image according to the state of use by the user. This eliminates the troublesomeness of the user consciously adjusting and inverting the display, and eliminates the need for the user to manually perform the display reversing switch, so that another function can be provided in the newly created space.

According to the display device of the eighth aspect, when the liquid crystal display device and the flat display device are used in the opened state, the display of one display device is referred to while the display of the other display device is input. Can edit. This makes it possible to obtain a large amount of information and an input function at the same time in a limited space.

According to the display device of the ninth aspect, when the device is used in the opened state, it is possible to perform pen inputting / editing work on the display of the other display device while referring to the display of the other display device. If you can use it when it is closed, you can input / edit by directly instructing the target of pen input / editing work with the pen.
Can edit. As a result, by giving the input permission only to the display device that can be directly instructed with the pen, the pen can be turned on while the scanning information of the light emitting display device is being supplied to the pen tablet drive circuit when used in the closed state. It is possible to prevent malfunction due to reading the display of the double-sided display device.

[Brief description of drawings]

FIG. 1 is a diagram showing an operation of an optical filter of a first embodiment of a display device of the present invention.

FIG. 2 is a side sectional view of the embodiment of FIG.

FIG. 3 is a perspective view showing an open state of the display device of the present invention.

FIG. 4 is a perspective view showing a closed state of the display device of the present invention.

FIG. 5 is a diagram showing an operation of a polarizing plate of the display device of the present invention.

FIG. 6 is a side sectional view of a third embodiment of the display device of the present invention.

FIG. 7 is a diagram showing polarization directions of polarizing plates of the example of FIG.

FIG. 8 is a side view showing a micro switch of a fourth embodiment of the display device of the present invention.

9 is a block diagram showing the configuration of the embodiment of FIG.

FIG. 10 is a block diagram showing a configuration of a fifth embodiment of the display device of the present invention.

FIG. 11 is a diagram for explaining the operation of the embodiment of FIG.

FIG. 12 is a diagram showing a display example of the embodiment of FIG.

FIG. 13 is a side sectional view of a sixth embodiment of the display device of the present invention.

FIG. 14 is a block diagram showing the configuration of the embodiment of FIG.

FIG. 15 is a block diagram showing another configuration of the sixth embodiment of the display device of the present invention.

FIG. 16 is a block diagram showing the configuration of a seventh embodiment of the display device of the present invention.

[Explanation of symbols]

 1,15,28 Optical filter 10,14,29,33 Polarizing plate 11,13,30,32 Glass substrate 12,31 Liquid crystal layer 16 Double-sided display device 17 Light emitting flat display device 18 Axis 34 Backlight 39 Micro switch 45 Pen Tablet 47 Scan information control circuit 48 Pen tablet drive circuit

Claims (9)

[Claims] 1. A display device having a liquid crystal display element having a polarizing plate on the surface thereof, which has an optical filter disposed on the polarizing plate, and is capable of displaying on both front and back surfaces. A display device, wherein a surface of the filter in contact with the polarizing plate transmits a part of incident light and reflects the other part, and the other surface absorbs the incident light. 2. A double-sided display device having a liquid crystal display element for displaying a reflection type image on one surface and a transmission type image for the other surface, and a flat display device having a light emitting element. In the display device, the flat display device is openably and closably supported so that the display surface faces the one surface of the liquid crystal display device. 3. The display device according to claim 2, wherein the double-sided display device is the display device according to claim 1. 4. The flat display device is a liquid crystal display device having a backlight, and the polarization directions of the polarizing plates on the respective surfaces which overlap each other when the liquid crystal display device and the double-sided display device are closed are the same. Claim 2 or 3 characterized by the above.
The display device according to claim 1. 5. The brightness of the light emitting element of the flat display device is increased in a closed state and is decreased in an open state in association with opening and closing of the double-sided display device and the flat display device. The display device according to claim 2, further comprising a brightness changing unit. 6. The double-sided display device and the flat-panel display device have a structure that opens and closes in a vertical direction with respect to a display direction, and the double-sided display device is closed in a state in which an image is mirror-inverted vertically. The display device according to any one of claims 2 to 5, further comprising image inverting means for displaying a normal image. 7. The double-sided display device and the flat-panel display device have a structure that opens and closes laterally with respect to the display direction, and the double-sided display device is closed in a state in which the image is mirror-inverted with respect to the left and right. The display device according to any one of claims 2 to 5, further comprising image inverting means for displaying a normal image. 8. The display device according to claim 2, further comprising a pen tablet for performing pen input. 9. The pen tablet is configured to read a state of a display surface to detect an input position, and the pen tablet is configured to perform pen input to the double-sided display device and the flat display device. The display device according to claim 8, wherein the display device is a display device.