JP2009053586A - Display control device and display body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display body performing color display with lower power consumption. <P>SOLUTION: A display control device 10 has: a first control means outputting a first signal which is used for control of display of a first display body and whose voltage value is switched at a prescribed timing to the first display body (EPD210) having a storage display element displaying a color of a prescribed wavelength using a material different from a cholesteric liquid crystal; and a second control means outputting a second signal having a voltage value changing an alignment state of cholesteric liquid crystal molecules at a timing determined based on a control timing to a second display body (Ch-LCD220) disposed on the first display body and having a liquid crystal layer having the cholesteric liquid crystal molecules and reflecting light of a wavelength different from the prescribed wavelength when the cholesteric liquid crystal molecules are in a prescribed alignment state. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a display body having a memory display element.

An information display device called “electronic paper”, which is thinner than conventional display devices, has been developed. Electronic paper is required to have low power consumption. Therefore, a storage-type display body such as an electrophoretic display (hereinafter referred to as “EPD”) is used for electronic paper. Here, the memory-type display body refers to a display body that can maintain display without supplying power.

In recent years, there is a demand for color display with electronic paper. In particular, in electronic paper used for viewing information mainly composed of characters (for example, newspaper articles, reports, documents, etc.) There is a demand to display an underline that draws a colored line below.

A typical color conversion technique is a color filter system. According to the color filter method, pixels having color filters of a plurality of colors (for example, three colors of red, green, and blue) are arranged (hereinafter, such arrangement of pixels is referred to as “arrangement color mixing method”). According to the arrangement color mixing method, three pixels of the display body are used to display one pixel in the data. In other words, considering that a display body having the same total number of pixels is used, there is a problem that the resolution of color display is reduced to 1/3 compared to single color display. I won't go into details,
There is also a problem that the reflectance decreases.

In order to avoid the problems caused by the arrangement color mixing method, a technique for stacking display bodies is known. Patent Document 1 discloses a technique for stacking an organic EL (Electroluminescence) display on an EPD. Patent Document 2 discloses a technique of stacking a display device capable of displaying at a higher speed than EPD on EPD. Both documents disclose a technique for compensating for the defect of EPD that “display redrawing is slow”.

JP 2004-30321 A WO2005 / 034068 International Publication Pamphlet

The techniques described in Patent Documents 1 and 2 are to stack a display body capable of displaying at a higher speed, that is, having higher power consumption, on the EPD.
In contrast, the present invention provides a display body that performs color display with lower power consumption.

In order to solve the above-described problems, the present invention relates to a display of the first display body with respect to a first display body having a memory display element that displays a color of a predetermined wavelength using a material different from that of cholesteric liquid crystal. First control means for outputting a first signal whose voltage value is switched at a predetermined control timing, and disposed on the first display body, and having cholesteric liquid crystal molecules, the cholesteric The second display body having a liquid crystal layer that reflects light having a wavelength different from the predetermined wavelength when the liquid crystal molecules are in a predetermined alignment state, the timing of the cholesteric liquid crystal molecules is determined based on the control timing. There is provided a display control device having second control means for outputting a second signal having a voltage value for changing an alignment state.
According to this display control device, the second signal is output at a timing determined based on the control timing.

In a preferred aspect, in the display control device, the second control means outputs a signal having a voltage value for changing the alignment state of the cholesteric liquid crystal molecules to homeotropic alignment for a predetermined time after the control timing, After a lapse of time, a signal having a voltage value for changing the alignment state of the cholesteric liquid crystal molecules to the focal conic alignment may be output.
According to this display control apparatus, the alignment state of the cholesteric liquid crystal molecules becomes the focal conic alignment after the home timing alignment for a predetermined time after the control timing.

In another preferred aspect, in the display control device, the second control means may switch the voltage value of the second signal at a timing that does not coincide with the control timing.
According to this display control apparatus, the timings at which the voltage values of the first signal and the second signal are switched do not match.

In still another preferred embodiment, in the display control device, the memory display element is an electrophoretic display element, and the control timing is determined so that the voltage value of the first signal is applied to the entire surface of the first display body. It is a timing at which the reset voltage to be changed to the predetermined color is switched, and the second control means, after the control timing, while the voltage value of the first signal is the reset voltage, the cholesteric liquid crystal molecules A signal for changing the alignment state to an alignment other than the homeotropic alignment may be output.
According to this display control device, while the reset voltage is applied to the electrophoretic display element,
The orientation state of the cholesteric liquid crystal molecules is an orientation other than the homeotropic orientation.

In addition, the present invention provides a first display body having a memory display element that displays a color of a predetermined wavelength using a material different from that of the cholesteric liquid crystal, and the cholesteric liquid crystal molecule disposed on the first display body. And a second display body having a liquid crystal layer that reflects light having a wavelength different from the predetermined wavelength when the cholesteric liquid crystal molecules are in a predetermined alignment state.
According to this display body, the second display body displays a color different from that of the first display body.

In a preferred embodiment, in the display body, the second display body may include a plurality of cholesteric liquid crystal layers, and each of the plurality of cholesteric liquid crystal layers may reflect light having different wavelengths.
According to this display body, the second display body displays a plurality of colors.

In another preferable aspect, in the display body, the resolution of the second display body may be lower than the resolution of the first display body.
According to this display body, the second display body has a lower resolution than the first display body.

1. Configuration FIG. 1 is a diagram illustrating a configuration of an information display device 10 according to an embodiment. Information display device 10
Is a device that displays information stored in a memory (not shown), such as electronic paper. The display control unit 100 is a device that drives the display body 200. In FIG. 1, only the configuration necessary for the description of the present embodiment is shown, but the information display device 10 includes a control device, a storage device, an input device, and the like.

The display body 200 includes an EPD 210 (first display body) and a cholesteric liquid crystal display (hereinafter referred to as “Ch-LCD”) 220 (second display).
The display body has two display bodies. Although not shown in FIG. 1, EPD2
10 and the Ch-LCD 220 are stacked in the thickness direction of the information display device 10, that is, in the direction perpendicular to the display surface.

The display control unit 100 includes two drive units, an EPD drive unit 110 (first control unit) and a Ch-LCD drive unit 120 (second control unit). The EPD driving unit 110 is connected to the EPD2
In order to control the display of 10, a control signal (first signal) whose voltage value is switched at a predetermined control timing is output. The Ch-LCD driving unit 120 controls the display of the Ch-LCD 220, so that a control signal (a voltage value is switched at a timing determined based on the control timing) (
2nd signal) is output. The CPU 130 is a control device that controls the components of the information display device 10. Of the functions of the CPU 130, the EPD drive unit 110 and the C
In order to explain the function of controlling the h-LCD driving unit 120, the CPU 13 in FIG.
0 is shown as an element of the display control unit 100. However, the function of the CPU 130 is not limited to this. Details of the display control unit 100 will be described later.

FIG. 2 is a diagram showing a cross-sectional structure of the display body 200. When the display surface is on top, Ch-LC
D220 is disposed on the EPD 210. The Ch-LCD 220 is a display body having cholesteric liquid crystal molecules. Cholesteric liquid crystal layer 22 containing cholesteric liquid crystal molecules
3 is sandwiched between a glass substrate 221 and a glass substrate 225. A data electrode (column electrode) 222 is provided on the lower surface of the glass substrate 221. On the upper surface of the glass substrate 225,
Scan electrodes (row electrodes) 224 are provided. Pixels are formed corresponding to positions where the data electrodes 222 and the scanning electrodes 224 intersect when the display body 200 is viewed from above. In one pixel, a voltage corresponding to the potential difference between the data electrode 222 and the scan electrode 224 is applied to the cholesteric liquid crystal layer 223. The orientation of the cholesteric liquid crystal molecules is determined by the voltage (more precisely, power) applied to the cholesteric liquid crystal layer 223. Cholesteric liquid crystal molecules reflect light (for example, red) having a specific wavelength according to the alignment state. Here, a chiral agent (spiral inducing agent) is added to the cholesteric liquid crystal layer 223. By adjusting the concentration of the chiral agent, the wavelength of light reflected by the cholesteric liquid crystal layer 223 can be designed to a desired wavelength.

FIG. 3-5 is a diagram illustrating an alignment state of cholesteric liquid crystal molecules. 3 shows planar alignment (hereinafter referred to as “P alignment”), and FIG. 4 shows focal conic alignment (hereinafter referred to as “F alignment”).
FIG. 5 shows homeotropic orientation (hereinafter referred to as “H orientation”). In the P orientation, the cholesteric liquid crystal layer 223 reflects light having a specific wavelength λ among incident light. This phenomenon is called “specific wavelength reflection”. In the F orientation, the cholesteric liquid crystal layer 223 weakly scatters incident light, that is, almost transmits it. At this time, since the cholesteric liquid crystal layer 223 looks transparent, an image displayed on the EPD 210 can be seen from above. Cholesteric liquid crystal is a bistable material, and can maintain the P orientation or the F orientation without supplying power. Whether the cholesteric liquid crystal molecules take the P orientation or the F orientation depends on the voltage applied to the cholesteric liquid crystal layer 223.

In the H alignment, the cholesteric liquid crystal layer 223 transmits incident light. In order to maintain the H alignment, it is necessary to apply a predetermined voltage (for example, 40 V) to the cholesteric liquid crystal layer 223. The H and F orientations are common in that they transmit incident light. Light transmittance is higher in the H alignment than in the F alignment, but the H alignment also consumes more power.

A description will be given with reference to FIG. 2 again. EPD210 is a material different from cholesteric liquid crystal,
Here, it is formed by the electrophoresis microcapsule 214. The electrophoresis microcapsule 214 includes white particles 215 and black particles 216 inside. The electrophoresis microcapsule 214 is applied to the glass substrate 211 provided with the common electrode 212 by a binder 213 such as silicon resin. The common electrode 212 is an electrode formed of a transparent material such as ITO (Indium Titan Oxide). The binder 213 is sandwiched between a glass substrate 211 and a thin film transistor (TFT) substrate 218. TFT substrate 21
Reference numeral 8 denotes a TFT formed on a glass substrate. A pixel electrode 217 is provided on the upper surface of the TFT substrate 218. One TFT is provided for one pixel electrode.
The TFT is a switching element that turns on and off a signal applied to the pixel electrode 217.
A voltage corresponding to the potential difference between the common electrode 212 and the pixel electrode 217 is applied to the electrophoresis microcapsule 214. The white particles 215 are negatively charged and move to the common electrode 212 side or the pixel electrode 217 side according to the potential difference between the common electrode 212 and the pixel electrode 217. When the white particles 215 move to the common electrode 212 side, white is displayed. White particles 215 form pixel electrode 2
When moving to the 17 side, black is displayed. Thus, the EPD 210 displays a color having a wavelength different from the wavelength reflected by the cholesteric liquid crystal layer 223.

FIG. 6 is a diagram illustrating an image displayed on the display body 200. The EPD 210 displays main content to be displayed. In this example, the characters “Ainoue Kakikaku Kosashi Sususei Natsu Nino” are displayed. Characters are displayed in black and backgrounds other than characters are displayed in white. Ch-LCD 220 is a color different from these colors, in this example red,
Display lines, squares, circles, and other shapes. The marker M is a quadrangle that is displayed over the character. The underline U is a line displayed below the character. The portions other than these figures are transparent, and when the display body 200 is viewed from above, the image displayed on the EPD 210 can be seen. When viewed from the user, an image in which a marker or an underline is added to a specific character can be seen.

2. Operation Next, the operation of the display control unit 100 will be described. Hereinafter, a case where color display is performed (example 1), a case where high image quality is achieved without performing color display (example 2), and a case where low power consumption is achieved without performing color display (example 3) will be described.

2-1. Example 1 (color display)
FIG. 7 is a diagram illustrating the control signal switching timing in Example 1. In FIG. FIG. 8 is a flowchart showing the operation of the display control unit 100 in Example 1. The flow of FIG.
The process starts when an instruction to redraw the screen indicating that color display is performed is input.

In step S <b> 100, the CPU 130 controls the Ch-LCD driving unit 120 so as to output a control signal for setting the cholesteric liquid crystal molecules to the F alignment (hereinafter, this process is referred to as “F alignment driving”). The Ch-LCD driving unit 120 outputs a control signal according to the CPU 130.
In step S101, CPU 130 a predetermined time _{T 11} waits. During this time, C
The h-LCD driving unit 120 outputs a control signal for driving the F orientation. In this way, when the cholesteric liquid crystal molecules are in the F orientation, the user can see an image redrawn in the EPD 210.

In step S102, the CPU 130 displays black on the entire surface of the EPD 210 (
Hereinafter, this process is referred to as “black reset driving”) so that a control signal is output.
10 is controlled. The EPD driving unit 110 outputs a control signal according to the CPU 130. That is, the time T ₁₁ in step S101 indicates the difference between the timing for starting the timing and black reset drive to start the F orientation drive.
In step S103, CPU 130 a predetermined time _{T 12} to wait. During this time, E
The PD driver 110 outputs a control signal for black reset driving the EPD 210. Also during this time, the Ch-LCD driving unit 120 outputs a control signal for driving the F orientation. That is,
The Ch-LCD 220 is driven in the F orientation for a time T ₁₁ + T ₁₂ .

In step S104, the CPU 130 controls the Ch-LCD driving unit 120 so as to output a control signal for redrawing the display of the Ch-LCD 220.
In step S105, CPU 130 a predetermined time _{T 13} to wait. During this time, C
The h-LCD driving unit 120 outputs a control signal for redrawing the display on the Ch-LCD 220. Also during this time, the EPD driver 110 outputs a control signal for black reset driving the EPD 210. That is, the EPD 210 is black reset driven for a time T ₁₂ + T ₁₃ .

In step S106, the CPU 130 displays white on the entire surface of the EPD 210 (
Hereinafter, this process is referred to as “white reset driving”) so that a control signal is output.
10 is controlled. The EPD driving unit 110 outputs a control signal according to the CPU 130.
In step S107, CPU 130 a predetermined time _{T 14} to wait. During this time, E
The PD driver 110 outputs a control signal for driving the EPD 210 to perform white reset. Also during this time, the Ch-LCD driving unit 120 outputs a control signal for redrawing the display of the Ch-LCD 220.

In step S108, the CPU 130 controls the EPD driving unit 110 so as to output a control signal for redrawing the display of the EPD 210. The EPD driving unit 110 is a CPU 1
The control signal is output according to 30.
In step S109, CPU 130 a predetermined time _{T 15} to wait. During this time, E
The PD driver 110 outputs a control signal for redrawing the display of the EPD 210. Time T ₁₅
When elapses, the CPU 130 controls the EPD driving unit 110 so as to stop the power supply to the EPD 210. Thereafter, the EPD 210 maintains the display without supplying power. Also during this time, the Ch-LCD driving unit 120 outputs a control signal for redrawing the display of the Ch-LCD 220.

In step S110, CPU 130 a predetermined time _{T 16} to wait. During this time,
The Ch-LCD driving unit 120 outputs a control signal for redrawing the display of the Ch-LCD 220. That is, the Ch-LCD 220 is redrawn during the time T ₁₃ + T ₁₄ + T ₁₅ + T ₁₆ .

As described above, in Example 1, the EPD 210 and the Ch-LCD 220 are controlled such that the switching timing of the applied voltage does not match between the EPD 210 and the Ch-LCD 220, that is, the switching timing of the applied voltage is different. . As a result, the peak power of the system decreases (the increase in peak power is suppressed), so that a voltage drop due to the internal resistance of a power source such as a battery is reduced. That is, the battery lasts longer.

2-2. Example 2 (High quality without color display)
FIG. 9 is a diagram illustrating the control signal switching timing in the second example. FIG. 10 shows Example 2
It is a flowchart which shows operation | movement of the display control part 100 in. The flow in FIG. 10 is started, for example, when a screen redrawing instruction indicating that high image quality is performed without performing color display is input.

In step S200, the CPU 130 controls the Ch-LCD driving unit 120 to drive the Ch-LCD 220 in the F orientation. The Ch-LCD driving unit 120 includes a CPU 130.
To output a control signal.
In step S201, CPU 130 a predetermined time _{T 21} to wait. During this time, C
The h-LCD driving unit 120 outputs a control signal for driving the F orientation.

In step S202, the CPU 130 controls the EPD driving unit 110 so as to drive the EPD 210 to black reset. The EPD driving unit 110 outputs a control signal according to the CPU 130.
In step S203, CPU 130 a predetermined time _{T 22} to wait. During this time, E
The PD driver 110 outputs a control signal for black reset driving the EPD 210. Also during this time, the Ch-LCD driving unit 120 outputs a control signal for driving the F orientation.

In step S204, the CPU 130 controls the EPD driving unit 110 so that the EPD 210 is white-reset driven. The EPD driving unit 110 outputs a control signal according to the CPU 130.
In step S205, CPU 130 a predetermined time _{T 23} to wait. During this time, E
The PD driver 110 outputs a control signal for driving the EPD 210 to perform white reset. Also during this time, the Ch-LCD driving unit 120 outputs a control signal for driving the F orientation.

In step S206, the CPU 130 controls the EPD driving unit 110 so as to output a control signal for redrawing the display of the EPD 210. The EPD driving unit 110 is a CPU 1
The control signal is output according to 30.
In step S207, CPU 130 a predetermined time _{T 24} to wait. During this time, E
The PD driver 110 outputs a control signal for redrawing the display of the EPD 210. Time T ₂₄
When elapses, the CPU 130 controls the EPD driving unit 110 so as to stop the power supply to the EPD 210. Thereafter, the EPD 210 maintains the display without supplying power. Also during this time, the Ch-LCD driving unit 120 outputs a control signal for driving the F orientation. That is, the Ch-LCD 220 is driven in the F orientation for the time T ₂₁ + T ₂₂ + T ₂₃ + T ₂₄ .

In step S <b> 208, the CPU 130 controls the Ch-LCD driving unit 120 so as to output a control signal for setting the cholesteric liquid crystal molecules to the H alignment (hereinafter, this process is referred to as “H alignment driving”). The Ch-LCD driving unit 120 outputs a control signal according to the CPU 130.
In step S209, CPU 130 a predetermined time _{T 25} to wait. During this time, C
The h-LCD driving unit 120 outputs a control signal for driving the H alignment. When the time T ₂₅ has elapsed, the CPU 130 stops the power supply to the Ch-LCD 220 so as to stop the power supply to the Ch-LCD 220.
The drive unit 120 is controlled. Thereafter, the Ch-LCD 220 maintains the display without supplying power.

As described above, according to Example 2, after the EPD 210 is redrawn, a control signal for setting the cholesteric liquid crystal molecules to the H orientation is supplied to the Ch-LCD 220 for a predetermined period. Since the H orientation has a higher transmittance than the F orientation, after the EPD 210 is redrawn, the predetermined period is C
The h-LCD 220 has a higher transmittance, that is, a more transparent state. Thereby, the user can recognize the image of EPD210 more clearly. Ch-LCD2
Since power is supplied to 20 only when necessary, an increase in power consumption can be suppressed.

2-3. Example 3 (Low power consumption without color display)
FIG. 11 is a diagram illustrating the control signal switching timing in Example 3. FIG. 12 is a flowchart illustrating the operation of the display control unit 100 in the second example. The flow in FIG. 12 is started, for example, when a screen redraw instruction is input indicating that power consumption is reduced without performing color display.

The flow in FIG. 12 corresponds to the flow in FIG. 10 that does not perform H orientation driving. That is, the processes in steps S300 to S306 are performed in the same manner as the processes in steps S200 to S206 in FIG. In step S307, the predetermined time _{T 24} to wait. During this time, the EPD driving unit 110 outputs a control signal for redrawing the display of the EPD 210. Also,
During this time, the Ch-LCD driving unit 120 outputs a control signal for driving the F orientation. Time T ₂₄
When elapses, the CPU 130 controls the EPD driving unit 110 and the Ch-LCD driving unit 120 so as to stop the power supply to the EPD 210 and the Ch-LCD 220. Thereafter, the EPD 210 and the Ch-LCD 220 maintain the display without supplying power.

As described above, according to Example 3, after the EPD 210 is redrawn, the control signal for setting the cholesteric liquid crystal molecules to the F alignment other than the H alignment is Ch-L for a predetermined period.
It is supplied to CD220. The F orientation has a lower transmittance than the H orientation, but the power consumption is lower.
Power consumption is further reduced.

3. Other Embodiments The present invention is not limited to the above-described embodiments, and various modifications can be made. Common reference numerals are used for elements common to the embodiment. Also, two or more of the modifications described below may be used in combination.

In the above-described embodiment, the CPU 130 has a function of controlling the EPD driving unit 110 and the Ch-LCD driving unit 120. However, a control device other than the CPU 130 may have this function. For example, a control device specialized in the function of controlling the EPD driving unit 110 and the Ch-LCD driving unit 120 may be provided, and this control device may be used.

In the above-described embodiment, the example in which the EPD is used as the first display body has been described.
However, the first display body is not limited to EPD. An electrochromic display, a rotating ball display, or other memory display may be used (except for those using a cholesteric liquid crystal).

The colors that can be displayed by the EPD 210 and the Ch-LCD 220 are not limited to those described in the embodiment. Any color may be used.

Timing for switching the voltage value of the control signal (that is, timing for switching drive stages such as F alignment driving, H alignment driving, black reset driving, white reset driving, and redrawing) is not limited to that shown in FIGS. . For example, in the example of FIG. 7, the rewriting time of the Ch-LCD 220 is longer than the rewriting time of the EPD 210, but the rewriting time of the Ch-LCD 220 may be shorter. Further, the timing for stopping the power supply to the Ch-LCD 220 is later than the timing for stopping the power supply to the EPD 210.
The timing at which the power supply to the vehicle is stopped may be earlier. The same applies to other timings and other examples. In short, it is only necessary that the timing for switching the control signal output from the EPD driving unit 110 and the timing for switching the control signal output from the Ch-LCD driving unit 120 satisfy a predetermined relationship. That is, the timing for switching the control signal output from the Ch-LCD driving unit 120 may be determined based on the timing for switching the control signal output from the EPD driving unit 110.

The Ch-LCD 220 may include a plurality of cholesteric liquid crystal layers that each reflect light having different wavelengths. According to this display body, for example, a marker or an underline can be attached with two colors of red and yellow.

The EPD 210 and the Ch-LCD 220 may have different resolutions. In particular, EPD
If the main content is displayed and the writing such as a marker or an underline is displayed on the Ch-LCD 220, the resolution of the Ch-LCD 220 may be lower than the resolution of the EPD 210. By reducing the resolution of the Ch-LCD 220, the display redrawing is further accelerated.

It is a figure showing composition of information display device 10 concerning one embodiment. 4 is a diagram showing a cross-sectional structure of a display body 200. FIG. It is a figure which shows planar orientation. It is a figure which shows a focal conic orientation. It is a figure which shows homeotropic orientation. 5 is a diagram illustrating an image displayed on a display body 200. FIG. It is a figure which shows the switching timing of the control signal in Example 1. 6 is a flowchart illustrating an operation of the display control unit 100 in Example 1. It is a figure which shows the switching timing of the control signal in Example 2. FIG. 10 is a flowchart illustrating an operation of the display control unit 100 in Example 2. 10 is a diagram illustrating control signal switching timing in Example 3. FIG. 14 is a flowchart illustrating an operation of the display control unit 100 in Example 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Information display apparatus, 100 ... Display control part, 110 ... EPD drive part, 120 ... Ch-LC
D drive unit, 130 ... CPU, 200 ... display body, 210 ... EPD, 211 ... glass substrate, 2
DESCRIPTION OF SYMBOLS 12 ... Common electrode, 213 ... Binder, 214 ... Electrophoresis microcapsule, 215 ... White particle, 216 ... Black particle, 217 ... Pixel electrode, 218 ... TFT substrate, 220 ... Ch-LC
D, 221 ... glass substrate, 222 ... data electrode, 223 ... cholesteric liquid crystal layer, 224
... Scanning electrode, 225 ... Glass substrate

Claims (7)

A first display body having a memory display element that displays a color of a predetermined wavelength using a material different from that of the cholesteric liquid crystal is used for controlling the display of the first display body, and voltage is applied at a predetermined control timing. First control means for outputting a first signal whose value is switched;
A second liquid crystal layer disposed on the first display body, having a cholesteric liquid crystal molecule, and having a liquid crystal layer that reflects light having a wavelength different from the predetermined wavelength when the cholesteric liquid crystal molecule is in a predetermined alignment state; And a second control unit that outputs a second signal having a voltage value for changing the alignment state of the cholesteric liquid crystal molecules to the display body at a timing determined based on the control timing. The second control means outputs a signal having a voltage value for changing the alignment state of the cholesteric liquid crystal molecules to homeotropic alignment for a predetermined time after the control timing, and after the predetermined time has elapsed, The display control apparatus according to claim 1, wherein a signal having a voltage value for changing the alignment state to a focal conic alignment is output. The display control apparatus according to claim 1, wherein the second control unit switches the voltage value of the second signal at a timing that does not coincide with the control timing. The memory display element is an electrophoretic display element;
The control timing is a timing at which the voltage value of the first signal is switched to a reset voltage that changes the entire surface of the first display body to the predetermined color.
After the control timing, the second control means outputs a signal for changing the alignment state of the cholesteric liquid crystal molecules to an alignment other than homeotropic alignment while the voltage value of the first signal is the reset voltage. The display control apparatus according to claim 1. A first display body having a memory display element that displays a color of a predetermined wavelength using a material different from the cholesteric liquid crystal;
A second liquid crystal layer disposed on the first display body, having a cholesteric liquid crystal molecule, and having a liquid crystal layer that reflects light having a wavelength different from the predetermined wavelength when the cholesteric liquid crystal molecule is in a predetermined alignment state; A display body having a display body. The second display has a plurality of cholesteric liquid crystal layers;
The display body according to claim 5, wherein each of the plurality of cholesteric liquid crystal layers reflects light having a different wavelength. The display body according to claim 5, wherein the resolution of the second display body is lower than the resolution of the first display body.

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