JP2000274923A - Refrigerator equipped with liquid crystal display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To permit the indication of various informations without consuming any electric power for the maintenance of the indication by a method wherein a liquid crystal display, constituted of a liquid crystal having memory property, is arranged. SOLUTION: A refrigerator body 1 is constituted of upper and-lower two chambers while a liquid crystal display 10, constituted of a liquid crystal having memory property, is fitted into a recess on the upper door 3. The liquid crystal display 10 is equipped with a full color reflection type liquid crystal indicating element 100, a front surface illuminating light 11, an optical detection sensor 12, a data receiving unit 13, a card insertion port 14, a letter writing pen 15 and a writing switch 16 for writing a picture, indicated at present, again. A secondary battery is accommodated as the driving power source of the liquid crystal display 10 and the power supply unit of the refrigerator body 1 is used for the charging of the secondary battery while the output contact of a charging control circuit is provided in the recess to supply an electric power by contacting the electrode of the secondary battery with the contact.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator, and more particularly to a refrigerator having a liquid crystal display for displaying various information.

[0002]

2. Description of the Related Art Usually, the surface of a refrigerator is flat and has no pattern. Therefore, a memo or a recipe is pasted with a magnet or an adhesive tape, or a whiteboard is magnetically attached and a schedule or the like is written with a marker. ing.
However, there is a limit to the amount of information that can be displayed by pasting with a magnet or the like. Not only is the use of a whiteboard the same, but there are also problems such as erasure when information is erased, scattering, and dirty hands. In addition, the displayable form is only characters or schematic drawings, and it is usually difficult to write a precise image.

On the other hand, Japanese Patent Application Laid-Open No. 9-119768 discloses that a liquid crystal display is provided on the surface of a refrigerator.
It has been proposed in Japanese Patent Application Laid-Open No. 8-35759. But,
The displays proposed in these documents use a non-memory liquid crystal which requires power to maintain the display.
Refrigerators consume a large amount of power among home appliances, and reduction of power consumption is a major issue from the viewpoint of energy saving. Therefore, the addition of a non-memory display increases power consumption and departs from the demands of the times. Of course, even in the case of a display using a non-memory liquid crystal, if a timer is incorporated and the power supply is turned off after a lapse of a predetermined time, energy can be saved, but the display screen is also erased. There is a problem that.

[0004] In view of such circumstances, an object of the present invention is to provide a refrigerator having a liquid crystal display capable of displaying various information without consuming power for maintaining the display. .

[0005]

In order to achieve the above objects, the refrigerator according to the present invention is provided with a liquid crystal display constituted by using a liquid crystal having a memory function. If a liquid crystal having memory properties is used, power is not required except for updating the screen (to maintain the display state), which contributes to energy saving. In addition, the display contents can be abundantly included and arbitrarily rewritable, so that there is no problem that the data is erased but scattered at the time of erasure like a whiteboard.

It is preferable to use a chiral nematic liquid crystal as the liquid crystal having a memory property. This is because a display having a relatively large screen can be manufactured at low cost. Further, in the present invention, the liquid crystal display is preferably detachable from the refrigerator body. When the power supply is shared with the refrigerator main body, the display information is maintained even if the display is detached from the main body because of having the memory property, and the display can be moved to an arbitrary place.

Information displayed on such a liquid crystal display includes calendar information, recipe information, message information,
Inventory information, appreciation image information, and reception information can be given. These may be arbitrarily switched and displayed.
As the input means, a touch sensor or a pen input means may be provided.

[0008] Further, by providing power to a drive circuit of the liquid crystal display to write information in the liquid crystal display, and when the information writing to the liquid crystal display is completed, there is provided control means for stopping the power supply to the drive circuit. The energy saving effect increases. Further, the driving source of the liquid crystal display may be a secondary battery, and the power source of the refrigerator body may be used for charging.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a refrigerator having a liquid crystal display according to the present invention will be described below with reference to the accompanying drawings.

(Overall Structure of Refrigerator) In FIGS. 1 and 2, reference numeral 1 denotes a refrigerator main body, which is composed of two upper and lower compartments, 2 is a lower door, and 3 is an upper door. Reference numeral 10 denotes a liquid crystal display, which is fitted into the recess 4 of the upper door 3. The liquid crystal display 10 includes a full-color reflective liquid crystal display element 100 described in detail below, and further includes a front illumination light 11, a light detection sensor 12, a data receiving unit 13, a card slot 14, and a pen 15 for writing characters. A write switch 16 for rewriting the currently displayed screen is provided. Further, a bar code reader 17 capable of reading a bar code attached to the food and transmitting it as wireless data is also provided. The bar code reader 17 with the transmitter is mounted on a holder 5 provided on the upper door 3 as shown in FIG. Is housed. The pen 15 is of course detachable.

The liquid crystal display 10 is formed in a thin plate shape and is fitted into the recess 4 of the upper door 3. You may make it stick directly on the surface of the upper door 3 without forming the recessed part 4. Further, it may be fixed completely, or may be set detachably with respect to the upper door 3. To make it detachable, for example, as shown in FIG. 3, a magnet 20 may be attached to the back surface, or a hole 21 may be formed and hung on a bar (not shown) provided on the upper door 3. If the handle 22 is provided, it is convenient for attachment and detachment. By making the liquid crystal display 10 detachable, the liquid crystal display 10 can be used alone as a bulletin board or an amount with a viewing image, or as a viewer for various information. Further, repair and replacement of the liquid crystal display 10 are facilitated.

As a driving source of the liquid crystal display 10, a secondary battery is incorporated. The power supply unit of the refrigerator body 1 is used for charging the secondary battery, and the recess 4 is provided with an output contact 6 (see FIG. 2) of a charge control circuit. The electrode of the secondary battery comes into contact with the contact 6 and is supplied with electric power.

There are various types of information displayed on the liquid crystal display 10, and typical ones are calendar information,
It is recipe information, message information, stock information in a warehouse, image information for appreciation, and information received from a communication line. The recipe information and the image information for appreciation are stored in dedicated memory cards, respectively. When the memory card is inserted into the insertion slot 14, the contents of the card are automatically read and displayed. In other words, the insertion slot 14 and the memory card inserted therein also function as a switch (selection) switch of display information.

(Power Supply / Control Circuit) FIG. 4 shows a power supply / control circuit of the refrigerator body 1 and the liquid crystal display 10. The circuit of the main body 1 includes a power distributor 31 of a commercial power supply, and the power distributor 31.
32, a charging control circuit 33,
It comprises an input / output device 34 such as a compressor. The CPU 32 exchanges signals with the charge control circuit 33 and the input / output device 34.

The circuit of the liquid crystal display 10 includes a secondary battery 35 charged by the charging control circuit 33,
6, a central processing unit (CPU) 40 supplied with electric power from the power distributor 36, and an input / output device 43. The central processing unit 40 exchanges signals with the input / output device 43.

FIG. 5 shows the circuit of the liquid crystal display 10 in more detail. The distributor 36 is further provided with the LCD controller 5.
2. The power is also supplied to the other control circuit 42 and the booster circuit 51. The booster circuit 51 supplies power of a predetermined specification to the driving IC 53. The LCD controller 52 is a central processing unit 4
0 to operate the drive IC 53, and the liquid crystal display element 1
00 is drive-controlled.

The central processing unit 40 starts operating when the battery 35 is mounted or when the battery 35 is charged to a required amount. Further, the booster circuit 51 can be turned on / off by a command from the central processing unit 40, and when the booster circuit 51 is off, power consumption can be extremely reduced.

As shown in FIG. 6, the central processing unit 40
ROM 45 storing various programs and data, nonvolatile RAM 46 storing various data including display information
A signal from the light detection sensor 12 and the writing switch 16 is input, and further, a signal from a data transmission device provided in the refrigerator body 1 and a signal from the bar code reader 17 with the transmitter are transmitted to a data reception unit. 13. Further, a signal from a touch panel 140 provided on the surface of the liquid crystal display element 100 is also input. Also,
The central processing unit 40 has a built-in calendar function described below, and exchanges signals with a read / write device 47, an image processing device 55, and an image memory 56 of a card inserted from the insertion slot 14. The image processing device 55 performs necessary image processing on image data transmitted from the data receiving unit 13 or the card reading / writing device 47 and performs image processing on the image memory 5.
6 and the information written on the touch panel 140 is also sent to the image memory 56 as image data. This image memory 5
LCD controller 5 based on the data stored in
2 controls the drive IC 53, sequentially applies a voltage between each scanning electrode and the signal electrode of the liquid crystal display element 100, and writes an image on the liquid crystal display element 100. The image data stored in the image memory 56 is read out via the image processing device 55, subjected to necessary image processing, and transmitted to the card reading / writing device 47. Further, the central processing unit 4
0 controls the illumination light 11 via the illumination control unit 48.

By the way, communication (telephone) is provided to the refrigerator body 1.
Information such as weather forecasts, traffic information, event information, circulars, advertisements, and incoming e-mails is input via the line.
These pieces of information are input to the data receiving unit 13 using a wireless communication means such as infrared rays,
Can be displayed above. Therefore, the refrigerator can be used as a base for transmitting various information at home. Of course, the liquid crystal display 10 can maintain the display with zero power consumption except when it is necessary to rewrite, does not increase the power consumption of the refrigerator, and always supplies power from the refrigerator main body connected to the commercial power supply. Therefore, power can be supplied to the drive circuit of the liquid crystal display 10 whenever rewriting is necessary.

The power supply / control circuit is connected to the refrigerator body 1
The liquid crystal display 10 and the circuit of the liquid crystal display 10 are configured independently of each other. However, the liquid crystal display 10 may be integrated into the refrigerator main body 1 and both circuits may be integrated.

(Display Examples) Next, various display examples on the liquid crystal display element 100 will be described. Various display examples can be adopted in addition to the display examples shown in FIGS. 7 to 10 below.

FIG. 7 is a display example of food inventory management, which is a list display of the contents read from the bar code attached to the food by the bar code reader 17 with the transmitter and transmitted to the central processing unit 40. . Touch panel 1 on the right
Switch key 2 for switching to another screen (see FIGS. 8 to 9) by 40
01, up and down scroll keys 202, 203
Is displayed. Also, to rewrite the information of each item,
By touching the frame of the desired item, the item to be rewritten can be specified.

FIG. 8 is a display example of a recipe. in this case,
Keys 202 and 203 are used as UP / DOWN keys for switching a menu to a previous page and a subsequent page.

FIG. 9 shows a display example of the message board.
5 shows a state in which characters, images, and the like written on the touch panel 140 using the number 5 are displayed. The OK key 204 displayed in the upper part is for storing the contents written on the screen in the memory card. The key 205 is used to execute new writing, and the key 206 is used to execute screen erasing.

FIG. 10 shows a display example of a calendar. Each of the keys 201 to 206 has the same function as described above.
Further, since information is recorded in each date frame, a date to be written or erased can be designated by touching a desired date frame.

(Control Example) A control procedure of the liquid crystal display 10 by the central processing unit 40 will be described below with reference to flowcharts of FIGS.

FIG. 11 shows a main routine. When the battery 35 is loaded in the liquid crystal display 10 or the battery 35 is charged to a required amount, the central processing unit 40 is activated, and first,
In step S1, an internal RAM, a register, a timer, and the like are initialized. Then, display 1 (initial calendar) is executed in step S2, and brightness detection by the sensor 12 is executed in step S3. Thereafter, a power saving timer is started in step S4, and a sleep mode (power saving mode) is set in step S5.

In the sleep mode, supply of a clock to internal circuits such as a memory, a register, and a counter is stopped by itself except for a minimum necessary part. As a result, power supply to each input / output device is also stopped, and power consumption is reduced to a very small level. When the central processing unit 40 is in the sleep mode, it shifts to the wake-up mode and executes a predetermined process when receiving an interrupt signal. The power-saving timer can continue counting even when the central processing unit 40 is in the sleep mode.

FIG. 12 shows a brightness detection subroutine executed in step S3. Here, step S
At 11, data of the brightness around the liquid crystal display element 100 is input from the sensor 12, and at step S12, based on the data, whether or not the screen of the liquid crystal display element 100 is bright (whether or not it can be identified by human eyes). Judge. If it is bright, the process returns. If it is dark, the light 11 is turned on in step S13.

FIG. 13 shows a timer interrupt subroutine. This subroutine is executed when the power saving timer counts a predetermined time (for example, 5 minutes).
Is automatically started with an interrupt. First, it is determined whether or not the light 11 is turned on in step S21, and if so, the light 11 is turned off in step S22. Next, in step S23, “1” is added to the variable N, and the process proceeds to step S27 until the variable N exceeds “300”.
To enable all interrupts. Further, step S28
Resets and starts the power saving timer, and enters the sleep mode in step S29.

The variable N reaches "300" approximately one day when the count-up time of the power saving timer is set to 5 minutes. When the variable N reaches "300", that is, when the liquid crystal display When one day has passed without any change in the element 100, the screen currently displayed is written again in step S25, and the variable N is reset to "0" in step S26. This is performed for the purpose of automatically restoring the information after a lapse of one day, since the user may touch the liquid crystal display element 100 without knowing it and the display content may be partially damaged.

FIGS. 15 and 16 show an interrupt subroutine. This interruption may be caused by operating the touch panel 140, inputting data by infrared communication from the bar code reader 17 with a transmitter, or
The central processing unit 40 is put into a wake-up state and is executed.

Here, first, in step S30, the same brightness detection processing as described above with reference to FIG. 12 is performed.
As a result, there are operations on the touch panel 140, data input by infrared communication from the barcode reader 17 with a transmitter, insertion into the memory card insertion slot 14, and
When the surroundings are dark, the lighting is turned on. Then, the power saving timer is reset and started in step S31 so that an interrupt by the power saving timer does not occur while the operator operates the screen. In step S32, it is determined whether or not a key operation of the liquid crystal display 10 has been performed. judge. If there is a key operation, interruption by this operation is prohibited in step S33. Next, in step S34, it is determined whether or not the key operation is an operation on the touch panel 140,
If so, the process proceeds to step S35. Otherwise, it is determined that the write switch 16 has been operated, and the process proceeds to step S37 described later to perform rewriting. In step S35, it is determined whether or not the key operation is the operation of the display switching key 201. If so, step S3
In step 6, the display mode is cyclically changed from the currently displayed mode in a predetermined order, and in step S37, the entire display is rewritten. To change the display mode: Calendar, 2. Picture, 3. Message board, 4. 4. Food inventory management; Recipe, 6. This is the order of the received information (step S4
9 to S54).

When the power saving timer started in step S31 has counted a predetermined time, the above-described timer interrupt subroutine of FIG. 13 is executed, the central processing unit 40 enters the sleep mode, and the illumination light 1
The power supply to each of the input / output devices including No. 1 is stopped.
The power saving timer started in the following step S64 and the like is used for the same control.

By the way, the rewriting process in the step S37 is executed in order to restore the disturbance since there is a possibility that the display of the liquid crystal is disturbed when a part of the liquid crystal screen is pressed by the key operation. Normally, a display using a liquid crystal having no memory, such as a TN liquid crystal, updates the screen periodically in a short period of time. Therefore, it is not particularly necessary to provide such a process of rewriting the entire display. However, since the chiral nematic liquid crystal used in the present embodiment has a memory property in which the display is maintained even when the power supply is cut off, the screen is not updated in a short time, and the display update or restoration is not performed. Rewrite (update) all displays only when necessary. That is, at the time of image writing, the boosting circuit 51 is turned on to perform the boosting operation, and after the writing is completed, the power supply is stopped to turn off the boosting circuit 51. The same applies to rewriting performed in the following step S65 and the like.

Next, in step S48, the mode numbers 1 to 6 to be displayed are confirmed, and according to the numbers, step S49 is performed.
In S54, a predetermined display mode is executed. That is, number 1
Is the calendar mode of step S49, the picture mode of number 2 is step S50, the message board mode of number 3 is step S51, and the food inventory management mode of number 4 is step S50.
At 52, the recipe mode of No. 5 is executed at step S53, and the reception information mode of No. 6 is executed at step S54. The details will be described later.

On the other hand, if there is no key operation (N in S32)
O) In step S38, it is determined whether or not the memory card has been inserted into the insertion slot 14. If inserted, a data code indicating the type of card is input from the read / write device 47 in step S43. Then, in step S44, it is determined whether or not the data code has already been stored in the RAM 46. If the data code has been stored (if there is the same data code), the display mode number is changed to the data code of this card in step S45. I do. In this case, it is a card such as a picture or a recipe, and the display process is executed in any of steps S49 to S53 according to the display mode number.

If the same data code is not stored (YES in step S44), the contents of the card are inputted in step S46 and stored in the image memory 56, and the contents are displayed on the liquid crystal display element 100 in step S47. I do.

On the other hand, when the card is not inserted (NO in step S38), it is determined that the data receiving unit 13 has received data. If it is determined in step S39 that information has been received from the communication line, the display mode number is changed to 6 in step S40. Otherwise, it is determined that a barcode is to be transmitted from the barcode reader 17 with a transmitter. In S41, the data (food name, number and weight, date of manufacture, expiration date, etc.) is added, and the display mode number is changed to 4 in step S42.

FIGS. 16 and 17 show a subroutine for calendar display executed in step S49. In this calendar display, as shown in FIG.
OK key 2 in addition to P / DOWN keys 202 and 203
04, a new key 205, and an erase key 206 are displayed.

Here, first, a monthly display is performed in step S61, and the UP / DOWN key 20 is displayed in step S62.
Then, it is determined whether or not the operations of 2,203 have been performed. If the operation has been performed, the display is changed to the next month or the previous month in step S63, the power saving timer is reset and started in step S64, and the entire display is rewritten in step S65.

Next, after confirming that the erase key 206 has been operated in step S66, the stored contents and display of the image memory 56 are erased in step S67. When it is confirmed in step S68 that the new key 205 has been operated, a new creation is processed in step S69. The processing in steps S67 and S69 will be described with reference to FIG.

Next, at step S70, the display switching key 20
It is determined whether or not 1 has been operated, and if not, the process returns to step S62. If so, the power saving timer is reset and started in step S71, the display mode number is changed to 1 in step S72, and this subroutine ends.

As shown in FIG. 17A, the memory and display erasure process executed in step S67 is first performed.
In step S81, the process waits for the day specified by the pen 15, and when specified, only the scan line including the cell on the day specified in step S82 is driven and rewritten, and the frame of the specified day is indicated by a thick line. indicate. Further, step S8
In step 3, the power saving timer is reset and started, and in step S84, all the displays are rewritten. in this way,
By rewriting the entire screen after performing partial screen rewriting, it is possible to avoid the problem that the color is slightly different between the rewritten part and the non-rewritten part. Then, in step S85, the OK key 20
When the operation of No. 4 is confirmed, the display and the contents stored in the image memory 56 written in step S86 are deleted.

As shown in FIG. 17 (B), the new creation processing executed in step S69 is performed first in step S69.
At 91, it waits for the designation of the day by the pen 15, and when it is designated, at step S92, only the scanning line including the cell of the designated day is driven and rewritten, and the frame of the designated day is displayed by a thick line. I do. Further, in step S93, the power saving timer is reset and started, and in step S94
To rewrite all displays.

Further, in step S95, it waits for writing of a character by the pen 15, and when written, the power saving timer is reset and started in step S96, and the written content is stored in the image memory 56 in step S97. Rewriting of all the displays is performed based on the stored contents. Next, when the operation of the OK key 204 is confirmed in step S98, R is added as new data in step S99.
The data is stored in a predetermined area of the AM 46, and when a memory card is mounted, the data is stored in the memory card and the entire display is rewritten.

FIG. 18 shows a picture display subroutine executed in step S50. Here, first, the latest image, such as a picture or a photograph, displayed previously in step S101 is displayed. Next, in step S102, UP
It is determined whether the / DOWN keys 202 and 203 have been operated. If the operation has been performed, step S1
In step S104, the display of pictures, pictures, and the like stored in the RAM 46 or the memory card in advance is sequentially changed.
Resets and starts the power saving timer, and rewrites all displays in step S105.

Next, in step S106, the display switching key 2
01 is operated or not, and if not operated,
The process returns to step S102. If operated,
In step S107, the power saving timer is reset and started. In step S108, the display mode number is changed to 1, and the subroutine ends.

In the case of displaying a picture, the display of each picture may be made as small as possible or displayed inconspicuously so as not to obstruct the display of the picture as much as possible. Each key may be displayed by operating the touch panel 140.

FIGS. 19 and 20 show a message board display subroutine executed in step S51. In this message board display, as shown in FIG.
OWN keys 202 and 203, an OK key 204, a new key 205, and an erase key 206 are displayed.

Here, first, at step S111, the latest message content displayed last time is displayed. Next, in step S112, the UP / DOWN key 202,2
It is determined whether or not the operation No. 03 has been performed. If the operation has been performed, the message contents stored in the RAM 46 or the memory card in advance are sequentially changed in step S113,
In step S114, the power saving timer is reset and started, and in step S115, all the displays are rewritten.

Next, at step S116, the erase key 206
When it is confirmed that has been operated, the memory and the display are deleted in step S117. If it is confirmed in step S118 that the new key 205 has been operated, a new creation is processed in step S119. This step S
The processing in 119 will be described with reference to FIG.

Next, in step S120, the display switching key 2
01 is operated or not, and if not operated,
The process returns to step S112. If operated,
In step S121, the power saving timer is reset and started, and in step S122, the display mode number is changed to 1, and the subroutine ends.

As shown in FIG. 20, the new creation process executed in step S119 is performed first in step S13.
1 waits for a character to be written by the pen 15, and when written, resets and starts the power saving timer in step S132, and stores the written content in the image memory 56 in step S133, based on the stored content. Rewrite all display. Next, when the operation of the OK key 204 is confirmed in step S134, step S13
In step 5, the new data is stored in a predetermined area of the RAM 46. If a memory card is mounted, the new data is stored in the memory card and the entire display is rewritten.

FIG. 21 shows a subroutine of food stock management display (see FIG. 7) executed in step S52.
Here, first, an operation by pen-down is waited for in step S141, and when the operation is performed, the power saving timer is reset and started in step S142.
At 143, the entire display is rewritten. Next, step S
The key operation is determined in 144, and if the UP / DOWN key or the switching key has been operated, the process proceeds to step S141.
Return to step S145, if any other key is operated, identify the place where the pen is down in step S145, drive only the operation line including the cell of the designated item, perform rewriting, and display a frame with a thick line I do.

Next, in step S146, UP / DOWN
It is determined whether or not the operation of the keys 202 and 203 has been performed. If the UP key 202 is operated, the value of the location specified in step S147 is increased, and if the DOWN key 203 is operated, the value of the location specified in step S148 is decreased. Display element 1
00 is partially driven to perform rewriting. The processing here is for changing the numerical value of the item specified by the user.
For example, referring to FIG. 7, "number 2" of "carrot"
Is instructed and the DOWN key 203 is operated, the number is changed to “number 1”.

Next, in step S149, the power saving timer is reset and started, and in step S150, all the displays are rewritten. Further, the key operation is determined in step S151. If the UP / DOWN key or the switching key has been operated, the process returns to step S142. If any other key has been operated, step S15 is performed.
In step 2, it is determined whether or not the display switching key 201 has been operated.
If not, the process returns to step S146. If it has been operated, the display mode number is changed to 1 in step S153, the power saving timer is reset and started in step S154, and this subroutine ends.

FIG. 22 shows a recipe display subroutine (see FIG. 8) executed in step S53. Here, first, the recipe of "curry" which is the menu 1 is displayed in step S161, and the UP / DO is displayed in step S162.
It is determined whether the WN keys 202 and 203 have been operated. If the operation has been performed, the display is changed to the next menu stored in step S163, the power saving timer is reset and started in step S164, and the entire display is rewritten in step S165.

Next, at step S166, the display switching key 2
01 is operated or not, and if not operated,
The process returns to step S162. If operated,
In step S167, the power saving timer is reset and started. In step S168, the display mode number is changed to 1, and the subroutine ends.

FIG. 23 shows a reception information display subroutine executed in step S54. Here, first,
In step S171, the latest received information is displayed.
At 172, it is determined whether or not the UP / DOWN keys 202 and 203 have been operated. If the operation was performed,
In step S173, the display is sequentially changed, and in step S17
In step S4, the power saving timer is reset and started, and in step S175, all the displays are rewritten.

Next, at step S176, the display switching key 2
01 is operated or not, and if not operated,
The process returns to step S172. If operated,
In step S177, the power-saving timer is reset and started, and in step S178, the display mode number is changed to 1 and the subroutine ends.

(Liquid crystal display element and touch panel)
The liquid crystal display element 100 and the touch panel 140 each having a built-in liquid crystal exhibiting a cholesteric phase used in the liquid crystal display 10 will be described.

(Structure) FIG. 24 shows an example of a reflection type liquid crystal display device. In this liquid crystal display element 100, a red display layer 111R for displaying by selectively reflecting red and switching between transparent states is disposed on a light absorbing layer 121 provided on a support plate 130 made of a hard material for preventing bending. Then, a green display layer 111G for performing display by switching between green selective reflection and a transparent state is laminated thereon, and a blue display layer 111B for performing display by switching between blue selective reflection and a transparent state is further laminated thereon. It was done.

The touch panel 140 is a liquid crystal display element 100
Is provided on the surface of the liquid crystal display device 100 via a protective layer 148 made of a hard resin material. The protective layer 148 is provided to prevent a partial pressure from acting on the liquid crystal display element 100. The configuration of the touch panel 140 is conventionally known. The touch panel 140 is provided with strip-shaped transparent electrodes 143 and 144 on the opposing surfaces of the transparent substrates 141 and 142 to constitute a matrix sensor. A predetermined gap is maintained between the substrates 141 and 142 by a particulate spacer 146 and a surrounding sealing material 147, and an air layer 145 is sealed. A portion where the strip-shaped transparent electrodes 143 and 144 intersect is a sensing portion, and the sensing portion includes the display layers 11 described below.
It corresponds to each pixel of 1R, 111G, 111B.

Each display layer 111R, 111G, 111B
Has a structure in which a resin columnar structure 115, a liquid crystal 116 and a spacer 117 are sandwiched between transparent substrates 112 on which transparent electrodes 113 and 114 are formed, respectively. Transparent electrode 11
An insulating film 118 and an orientation control film 119 are provided on the 3, 114 as needed. Further, a sealing material 1 for sealing the liquid crystal 116 is provided on an outer peripheral portion (outside the display area) of the substrate 112.
20 are provided.

The transparent electrodes 113 and 114 are driven
C53 (131, 132) (see FIGS. 5, 6, and 27)
, And a predetermined pulse voltage is applied between the transparent electrodes 113 and 114, respectively. In response to the applied voltage, the display is switched between a transparent state in which the liquid crystal 116 transmits visible light and a selective reflection state in which visible light of a specific wavelength is selectively reflected.

Each color display layer 111R, 111G, 111B
Are formed of a plurality of strip-shaped electrodes arranged in parallel at a fine interval, and are opposed to each other so that the direction in which the strip-shaped electrodes are arranged is perpendicular to each other. Current is sequentially applied to these upper and lower strip electrodes. That is, display is performed by sequentially applying a voltage to each liquid crystal 116 in a matrix. This is called matrix driving. By performing such matrix driving sequentially or simultaneously for each color display layer, a full-color image is displayed on the liquid crystal display element 100.

More specifically, in a liquid crystal display device in which liquid crystal exhibiting a cholesteric phase is sandwiched between two substrates, display is performed by switching the state of the liquid crystal between a planar state and a focal conic state. When the liquid crystal is in the planar state, assuming that the helical pitch of the cholesteric liquid crystal is P and the average refractive index of the liquid crystal is n, light of wavelength λ = P · n is selectively reflected. Also,
In the focal conic state, the light is scattered when the selective reflection wavelength of the cholesteric liquid crystal is in the infrared light range, and transmits visible light when the wavelength is shorter than that. Therefore, by setting the selective reflection wavelength in the visible light range and providing the light absorbing layer on the side opposite to the observation side of the element, it is possible to display the selective reflection color in the planar state and display black in the focal conic state. In addition, by setting the selective reflection wavelength in the infrared light range and providing a light absorption layer on the side opposite to the observation side of the element, light in the infrared light range is reflected in the planar state, but the wavelength in the visible light range is reflected. Is transmitted, so that a black display and a white display due to scattering in the focal conic state are possible.

(Full Color Display) Each color display layer 111R,
The liquid crystal display element 100 in which 111G and 111B are stacked is
Red display can be performed by setting the blue display layer 111B and the green display layer 111G in a transparent state in which liquid crystals are in a focal conic arrangement, and setting the red display layer 111R in a selective reflection state in which liquid crystals are in a planar arrangement. Further, yellow display is performed by setting the blue display layer 111B in a transparent state in which liquid crystals are in a focal conic arrangement, and setting the green display layer 111G and the red display layer 111R in a selective reflection state in which liquid crystals are in a planar arrangement. Can be. Similarly, red, green, blue, white, cyan, magenta, yellow, and black can be displayed by appropriately selecting the state of each color display layer between a transparent state and a selective reflection state. Further, each color display layer 111R, 111G, 111
By selecting an intermediate selective reflection state as the state B, display of an intermediate color becomes possible, and it can be used as a full-color display element.

Each color display layer 1 in the liquid crystal display element 100
The stacking order of 11R, 111G and 111B is shown in FIG.
Cases other than those shown in FIG. However, considering that the transmittance of the light in the long wavelength region is higher than that in the short wavelength region, the selective reflection wavelength of the liquid crystal contained in the upper layer is changed to that of the liquid crystal contained in the lower layer. When the wavelength is shorter than the wavelength, more light is transmitted to the lower layer, so that a bright display can be performed. Therefore, the blue display layer 111B and the green display layer 111 are sequentially arranged from the observation side (the direction of arrow A).
It is most preferable to form the G, red display layer 111R, and this state provides the most preferable display quality.

(Various Materials of Display Element) As the transparent substrate 112, a colorless and transparent glass plate or a transparent resin film can be used. As a material for the transparent resin film,
Polycarbonate resin, polyether sulfone resin,
Polyethylene terephthalate resin, norbornene resin,
Polyarylate resins, amorphous polyolefin resins, modified acrylate resins, and the like are included. The characteristics of the resin film include high translucency, no optical anisotropy, dimensional stability,
It has surface smoothness, friction resistance, bending resistance, high electrical insulation, chemical resistance, liquid crystal resistance, heat resistance, moisture resistance, gas barrier properties, etc., and has the necessary characteristics according to the environment and application used. You just have to choose what you have.

The transparent electrodes 113 and 114 are made of ITO.
(Indium Tin Oxide) and other transparent electrodes can be used, and metal electrodes such as aluminum and silicon, or amorphous silicon and BSO (Bismuth Silicon Oxid) can be used.
A photoconductive film such as e) can also be used. Further, as for the lowermost transparent electrode 114, a black electrode can be used including the role as a light absorber.

As the insulating film 118, an inorganic film such as silicon oxide or an organic film such as a polyimide resin or an epoxy resin is used so as to function also as a gas barrier layer.
12 to prevent short circuit and improve the reliability of the liquid crystal. In addition, polyimide is a typical example of the orientation control film 119.

The liquid crystal 116 preferably exhibits a cholesteric phase at room temperature. In particular, a chiral nematic liquid crystal obtained by adding a chiral dopant to a nematic liquid crystal is preferable.

The chiral dopant is an additive having a function of twisting the molecules of the nematic liquid crystal when added to the nematic liquid crystal. By adding a chiral dopant to a nematic liquid crystal, a helical structure of liquid crystal molecules having a predetermined twist interval is generated, thereby exhibiting a cholesteric phase.

The chiral nematic liquid crystal has the advantage that the pitch of the helical structure can be changed by changing the addition amount of the chiral dopant, whereby the selective reflection wavelength of the liquid crystal can be controlled. In addition,
In general, as a term representing the pitch of the helical structure of liquid crystal molecules, a “helical pitch” defined by a distance between molecules when the liquid crystal molecules rotate 360 degrees along the helical structure of the liquid crystal molecules is used.

As a material used for the columnar structure 115, for example, a thermoplastic resin can be used. For this purpose, a material which is softened by heating and solidified by cooling, is desired not to cause a chemical reaction with a liquid crystal material to be used and to have appropriate elasticity.

As specific examples, for example, polyvinyl chloride resin, polyvinylidene chloride resin, polymethacrylate resin, polyacrylate resin, polyvinyl acetate resin, polystyrene resin, polyamide resin, polyethylene resin, polypropylene resin, fluorine resin Resins, polyurethane resins, polyacrylonitrile resins, polyvinyl ether resins, polyvinyl ketone resins, polyvinyl pyrrolidone resins, polycarbonate resins, chlorinated polyether resins, saturated polyester resins, and the like.

The columnar structure 115 may be formed from a material containing at least one of them or a mixture thereof, or a material containing at least one or a mixture thereof.

The above-mentioned substance is printed by a known printing method as shown in FIG.
As shown in the figure, printing is performed using a pattern so as to form a dot columnar shape. Depending on the size of the liquid crystal display element and the pixel resolution, the size of the cross-sectional shape, the arrangement pitch, and the shape (such as a cylinder, a drum, and a polygon) are appropriately selected. It is more preferable to arrange the columnar structures 115 preferentially between the electrodes 113 because the aperture ratio is improved.

The spacer 117 is preferably a particle made of a hard material that does not deform when heated or pressed. For example, finely divided glass fibers, inorganic materials such as ball-shaped silicate glass and alumina powder, or organic synthetic spherical particles such as divinylbenzene-based crosslinked polymers and polystyrene-based crosslinked polymers can be used.

As described above, the hard spacer 117 for maintaining the gap between the two substrates 112 at a predetermined size and the pair of substrates 112 adhered and supported in the display area according to the predetermined arrangement rule. By providing a resin structure 115 mainly composed of a thermoplastic polymer material,
2, the two substrates 112 are firmly supported, there is no uneven arrangement, and the generation of bubbles can be suppressed in a low-temperature environment.

(Production Example of Liquid Crystal Display Element) Here, a production example of the liquid crystal display element 100 will be briefly described.

First, a plurality of strip-shaped transparent electrodes are formed on two transparent substrates, respectively. The transparent electrode is an IT
After an O film is formed by a sputtering method or the like, patterning is performed by a photolithography method.

Next, a transparent insulating film or an orientation control film is formed on the transparent electrode forming surface of each substrate. The insulating film and the orientation control film can be formed by a known method such as a sputtering method, a spin coating method, or a roll coating method using an inorganic material such as silicon oxide or an organic material such as a polyimide resin. Note that a rubbing treatment is not usually performed on the alignment control film. Although the function of the alignment control film is not yet clear, it is considered that the presence of the alignment control film can give a certain degree of anchoring effect to the liquid crystal molecules, and the characteristics of the liquid crystal display element change over time. Can be prevented. In addition, a function as a color filter may be provided by adding a dye to these thin films to improve color purity and contrast.

Thus, a resin structure is formed on the electrode forming surface of one of the substrates provided with the transparent electrode, the insulating film, and the alignment control film. The resin structure is a printing method in which a paste-like resin material obtained by dissolving a resin in a solvent is extruded with a squeegee through a screen stencil or a metal mask, and printing is performed on a substrate mounted on a flat plate, a dispenser method, or an inkjet method. For example, it can be formed by a method in which a resin material is discharged onto a substrate from the tip of a nozzle, or a transfer method in which a resin material is supplied onto a flat plate or a roller and then transferred to the substrate surface. . It is desirable that the height at the time of forming the resin structure is larger than the desired thickness of the liquid crystal display layer.

On the electrode forming surface of the other substrate, a sealing material is provided using an ultraviolet curable resin, a thermosetting resin, or the like. The sealant is arranged in a continuous ring at the outer edge of the substrate. The arrangement of the sealing material, like the resin structure described above, a method of forming a resin by discharging a resin from the tip of a nozzle onto a substrate, such as a dispenser method or an inkjet method, a screen plate, a printing method using a metal mask, or the like, After the resin is formed on a flat plate or a roller, the resin may be transferred onto a transparent substrate by a transfer method or the like. Further, spacers are sprayed on the surface of at least one of the substrates by a conventionally known method.

Then, the pair of substrates are overlapped so that the electrode forming surfaces face each other, and heated while pressing from both sides of the pair of substrates. Pressing and heating are performed, for example, as shown in FIG. 26, by placing the substrate 112a on which the resin structure 115 is formed on the flat plate 150, and stacking the opposing substrate 112b,
The heating can be performed by passing between the roller 151 and the flat plate 150 while applying heat and pressure by the heating / pressing roller 151 from the end. By using such a method, a cell can be manufactured with high accuracy even using a flexible substrate having flexibility such as a film substrate. When the resin structure is formed from a thermoplastic polymer material, the resin structure is softened by heating and solidified by cooling, so that the two substrates can be bonded by the resin structure. When a thermosetting resin material is used as the sealing material, the sealing material may be cured by heating when the substrates are superposed.

In this superposition step, a liquid crystal material is dropped on one of the substrates, and the liquid crystal material is injected into the liquid crystal element simultaneously with the superposition of the substrates. In this case, the spacer may be included in the liquid crystal material in advance, and the spacer may be dropped on at least one of the substrates on which the strip-shaped electrode is formed.

The liquid crystal material can be filled in the entire area of the substrate by dropping the liquid crystal material on the edge of the substrate and spreading the liquid crystal material to the other end while overlapping the substrates with a roller. By doing so, it is possible to reduce the entrapment of bubbles generated when the substrates are overlapped with each other in the liquid crystal material.

Thereafter, the substrate is continuously pressed until the temperature of the substrate falls to at least the softening temperature of the resin material constituting the resin structure, and then the pressing is stopped. Further, a photo-curable resin material is used as a sealing material. If so, light irradiation is performed thereafter to cure the sealing material.

In the same procedure, the liquid crystal material is changed to one having a different selective reflection wavelength, and cells for blue display, green display, and red display are manufactured. The cells thus manufactured are stacked in three layers, these are attached with an adhesive, and a light absorbing layer is further provided as a lowermost layer to obtain a full-color liquid crystal display device.

(Driving Circuit and Driving Method of Display Element) As shown in FIG. 27, the pixel configuration of the liquid crystal display element 100 includes a plurality of scanning electrodes R1, R2 to Rm and a signal electrode C.
1, C2 to Cn (n and m are natural numbers). The scanning electrodes R1, R2 to Rm are connected to the scanning drive IC 13
1, and the signal electrodes C1, C2 to Cn are connected to the output terminals of the signal drive IC 132.

The scan driving IC 131 includes scan electrodes R1, R
A selection signal is output to a predetermined one of 2 to Rm to be in a selected state, and a non-selection signal is output to other electrodes to be in a non-selected state. The scan driving IC 131 sequentially switches the scan electrodes R1, R2 to R2 while switching the electrodes at predetermined time intervals.
A selection signal is applied to Rm. On the other hand, the signal drive IC 1
32 simultaneously outputs a signal corresponding to image data to each of the signal electrodes C1, C2 to Cn in order to rewrite each pixel on the scanning electrodes R1, R2 to Rm in the selected state. For example,
When the scanning electrode Ra is selected (a is a natural number satisfying a ≦ m), the scanning electrode Ra and each of the signal electrodes C1, C2 to Cn
, The pixels LRa-C1 to LRa-Cn at the intersection with are rewritten simultaneously. Thereby, the voltage difference between the scanning electrode and the signal electrode in each pixel becomes the rewriting voltage of the pixel,
Each pixel is rewritten according to the rewriting voltage.

The driving circuit is the above-mentioned central processing unit 40, LC
D controller 52, image processing device 55, image memory 5
6 and driving ICs 131 and 132, the LCD controller 52 controls the driving ICs 131 and 132 based on the image data stored in the image memory 56, and sequentially applies a voltage between each scanning electrode and signal electrode of the liquid crystal display element 100. To write an image on the liquid crystal display element 100.

Here, assuming that the first threshold voltage for untwisting the liquid crystal exhibiting the cholesteric phase is Vth1, after applying the voltage Vth1 for a sufficient time, the voltage is changed to the second threshold voltage lower than the first threshold voltage Vth1. When the voltage is lowered to the threshold voltage Vth2 or less, a planar state is set. Further, when a voltage of Vth2 or more and Vth1 or less is applied for a sufficient time, a focal conic state is established. These two states are stably maintained even after the voltage application is stopped. Also, Vth1 to Vth
By applying a voltage between the two, halftone display, that is, gradation display is possible.

When partial rewriting is performed, only specific scanning lines may be sequentially selected so as to include a portion to be rewritten. As a result, only necessary parts can be rewritten in a short time.

Rewriting of each pixel can be performed by the method described above. However, when an image is already displayed, all the pixels are reset to the same display state before rewriting in order to eliminate the influence of the image. Is preferred. The reset may be performed for all pixels at once or for each scan electrode. For example, it has been found that when resetting each pixel to the focal conic state, a relatively long time is required to obtain a sufficient transparent state. Therefore, it is preferable to collectively reset all the pixels to the focal conic state before rewriting because the rewriting time can be shortened as compared with the case where resetting is performed for each scanning electrode.

When partial rewriting is to be performed, resetting may be performed for each scanning line or may be collectively reset only between specific scanning lines including a portion to be rewritten.

In any case, when a write command is issued from the central processing unit 40, the boosting circuit 51 is turned on to apply the boosted voltage to the driving ICs 131 and 132, and the LCD controller 52 controls the driving ICs 131 and 132. Thus, writing is performed on the liquid crystal display element 100. Then, upon completion of the writing, at least the booster circuit 51 is turned off to immediately reduce the power consumption, or the power supply to the LCD controller 52 is stopped to stop the power supply to the drive circuit.

(Other Liquid Crystal Display Elements) In the liquid crystal display element 100, the element configuration in which the resin columnar structure is included in the liquid crystal display layer has been described. With such a configuration, it is possible to manufacture a light-weight liquid crystal display element having excellent display characteristics using a film substrate, and at the same time, it is easy to increase the size, the driving voltage is relatively small, and various excellent properties such as impact resistance are obtained. It has features and is particularly useful. However, the memory-like liquid crystal itself is not necessarily limited to this configuration, and the liquid crystal is dispersed in a conventionally known polymer three-dimensional network structure, or the polymer three-dimensional network structure is present in the liquid crystal. The liquid crystal display layer can be formed as a so-called polymer dispersed liquid crystal composite film. Further, as the liquid crystal having a memory property, a bistable liquid crystal exhibiting a cholesteric phase has been described as an example. However, the present invention is not limited to this, and a ferroelectric liquid crystal can be used.

[Brief description of the drawings]

FIG. 1 is a front view showing a refrigerator according to an embodiment of the present invention.

FIG. 2 is a perspective view showing the refrigerator, with a liquid crystal display removed.

FIG. 3 is a perspective view showing another embodiment of the liquid crystal display.

FIG. 4 is a block diagram showing a first example of a power supply / control circuit.

FIG. 5 is a block diagram showing more details of the first example.

FIG. 6 is a block diagram showing a second example of the control circuit.

FIG. 7 is an explanatory diagram showing a display example of food inventory management.

FIG. 8 is an explanatory diagram showing a display example of a recipe.

FIG. 9 is an explanatory view showing a display example of a message board.

FIG. 10 is an explanatory diagram showing a display example of a calendar.

FIG. 11 is a flowchart showing a main routine of a control procedure of the liquid crystal display.

FIG. 12 is a flowchart illustrating a subroutine of brightness detection processing.

FIG. 13 is a flowchart showing a subroutine of a timer interrupt process.

FIG. 14 is a flowchart illustrating a subroutine of interrupt processing.

FIG. 15 is a flowchart showing a subroutine of interrupt processing, and is a continuation of FIG. 14;

FIG. 16 is a flowchart illustrating a subroutine of calendar display processing.

FIG. 17 is a flowchart showing a subroutine of memory, display deletion and new creation during calendar display processing.

FIG. 18 is a flowchart showing a subroutine of picture display processing.

FIG. 19 is a flowchart showing a subroutine of message board display processing.

FIG. 20 is a flowchart showing a subroutine for new creation during message board display processing.

FIG. 21 is a flowchart showing a subroutine of food stock management display processing.

FIG. 22 is a flowchart showing a subroutine of a recipe display process.

FIG. 23 is a flowchart showing a subroutine of a reception information display process.

FIG. 24 is a cross-sectional view illustrating an example of a liquid crystal display element used as a display.

FIG. 25 is a plan view showing a state in which a columnar structure and a sealing material are formed on a film substrate of the liquid crystal display element.

FIG. 26 is an explanatory view showing a manufacturing process of the liquid crystal display element.

FIG. 27 is a block diagram showing a matrix drive circuit of the liquid crystal display element.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Refrigerator 6 ... Contact of a charge control circuit 10 ... Liquid crystal display 35 ... Secondary battery 40 ... Central processing unit (CPU) 51 ... Booster circuit 100 ... Liquid crystal display element 140 ... Touch panel

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] January 17, 2000 (2000.1.1)
7)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0032

[Correction method] Change

[Correction contents]

FIGS. 14 and 15 show an interrupt subroutine. This interruption may be caused by operating the touch panel 140, inputting data by infrared communication from the bar code reader 17 with a transmitter, or
The central processing unit 40 is put into a wake-up state and is executed.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0043

[Correction method] Change

[Correction contents]

Next, at step S70, the display switching key 20
It is determined whether or not 1 has been operated, and if not, the process returns to step S62. If so, the power saving timer is reset and started in step S71, the display mode number is changed to 2 in step S72, and this subroutine ends.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0048

[Correction method] Change

[Correction contents]

Next, in step S106, the display switching key 2
01 is operated or not, and if not operated,
The process returns to step S102. If operated,
In step S107, the power saving timer is reset and started. In step S108, the display mode number is changed to 3 , and the subroutine ends.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0053

[Correction method] Change

[Correction contents]

Next, in step S120, the display switching key 2
01 is operated or not, and if not operated,
The process returns to step S112. If operated,
In step S121, the power saving timer is reset and started, and in step S122, the display mode number is changed to 4 , and the subroutine ends.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0057

[Correction method] Change

[Correction contents]

Next, in step S149, the power saving timer is reset and started, and in step S150, all the displays are rewritten. Further, the key operation is determined in step S151. If the UP / DOWN key or the switching key has been operated, the process returns to step S142. If any other key has been operated, step S15 is performed.
In step 2, it is determined whether or not the display switching key 201 has been operated.
If not, the process returns to step S146. If so, the display mode number is set in step S153.
5 , the power saving timer is reset and started in step S154, and this subroutine is terminated.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0059

[Correction method] Change

[Correction contents]

Next, at step S166, the display switching key 2
01 is operated or not, and if not operated,
The process returns to step S162. If operated,
In step S167, the power saving timer is reset and started. In step S168, the display mode number is changed to 6 , and the subroutine ends.

[Procedure amendment 7]

[Document name to be amended] Drawing

[Correction target item name] Fig. 4

[Correction method] Change

[Correction contents]

FIG. 4

[Procedure amendment 8]

[Document name to be amended] Drawing

[Correction target item name] Fig. 6

[Correction method] Change

[Correction contents]

FIG. 6

[Procedure amendment 9]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG. 16

[Procedure amendment 10]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG.

[Procedure amendment 11]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG.

[Procedure amendment 12]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG. 21

[Procedure amendment 13]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shuichiro Kaneko 2-3-13 Azuchicho, Chuo-ku, Osaka-shi, Osaka Inside Osaka International Building Minolta Co., Ltd. (72) Inventor Katsuhiko Asai Azuchi-cho, Chuo-ku, Osaka-shi, Osaka No. 2-313 Osaka International Building Minolta Co., Ltd. F-term (reference) 2H088 EA22 GA03 GA17 HA01 HA03 HA06 HA07 JA17 MA20 2H093 NC02 NC28 NC50 NC72 ND39 NE01 NE04 NF17 5G435 AA16 BB12 EE13 LL03

Claims (10)

[Claims] 1. A refrigerator comprising a liquid crystal display configured using liquid crystal having memory properties. 2. The refrigerator according to claim 1, wherein the liquid crystal is a chiral nematic liquid crystal exhibiting a cholesteric phase at room temperature. 3. The refrigerator according to claim 1, wherein the liquid crystal display is detachably provided on the refrigerator main body. 4. A rechargeable battery as a driving source for the liquid crystal display, a contact connected to a power supply unit of a refrigerator body and capable of contacting an electrode of the rechargeable battery, and charging the rechargeable battery. 4. The refrigerator according to claim 1, further comprising a charging circuit. 5. The information displayed on the liquid crystal display is at least one of calendar information, recipe information, message information, stock information in a warehouse, image information for appreciation, and received information. The refrigerator according to claim 1, 2, 3, or 4. 6. The refrigerator according to claim 5, further comprising means for switching the display information to an arbitrary type. 7. The refrigerator according to claim 1, further comprising a touch sensor on a surface of the liquid crystal display. 8. The liquid crystal display according to claim 1, further comprising a pen input unit for inputting display information to said liquid crystal display. Or the refrigerator according to claim 7. 9. A control means for supplying power to the driving circuit of the liquid crystal display to write information in the liquid crystal display, and stopping the power supply to the driving circuit when the writing of information to the liquid crystal display is completed. Claim 1, Claim 2, Claim 3, Claim 4,
The refrigerator according to any one of claims 5, 6, 7, and 8. 10. A booster circuit for boosting a voltage from a power supply and supplying the boosted circuit to a drive circuit of the liquid crystal display, wherein the power supply to the drive circuit is stopped by disabling the booster circuit. The refrigerator according to claim 9, characterized in that: