CN1307246A

CN1307246A - Storage LCD driving method and driver

Info

Publication number: CN1307246A
Application number: CN 00101754
Authority: CN
Inventors: 陈其良; 陈绍光
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-01-22
Filing date: 2000-01-22
Publication date: 2001-08-08

Abstract

By utilizing the characteristic a storage LCD in zero electric field can store displayed content, one driver is utilized to drive several storage LCDs. The change over of the driven output port from the input port of one display to the input port of another is completed by a mechanical switch or an electronic switch. The storage LCD of the present invention is preferably linear array LCD box of cholesteric phase and when it is used as commodity price plate or other display with large amount of display content and slow update speed, great amount of dirvers and thus building cost may be saved.

Description

A kind of driving method of storage property LCD and device

The present invention relates to the driving method and the device of storage property LCD, refer to the method and apparatus of a plurality of LCD of driver drives of a kind of usefulness especially.

The development of LCD not only depends on the progress of new capability liquid crystal but also inseparable with the progress of driving method and drive unit.The research innovation great majority of driving method all are that a kind of of liquid crystal photoelectric characteristic utilized cleverly.Courage steroid one is to host and guest (GH) the type phase transformation or the ferroelectric liquid crystals box that are listed as (CH-N) phase transformation liquid crystal cell and surface-stable ferroelectric liquid crystals box (SSFLC) and are mixed with dyestuff, their electro-optical characteristic curves is that widely different line has bistable state, having bistable liquid crystal cell can become storage property LCD under suitable type of drive, liquid crystal cell can stably be stored displaying contents under zero electric field after stopping to apply drive pressure.Storage property liquid crystal cell can drive on a line one line ground one by one, thereby does not have the cross effect of common multi-thread driving, can not reduce picture quality so the capacity of display can be accomplished very big (infinitely great in principle).But increasing of pixel, the write time will increase, and makes the research of driving method concentrate on the raising writing speed.Shortened to 0.05ms the horizontal-scanning interval that recent research has made courage steroid one nematic phase become liquid crystal cell, the vertical interval of 1000 row is 50ms only, has approached Video Applications.Surface-stable ferroelectric liquid crystals box has then been realized the video demonstration already, has made high performance televisor screen, beginning and CRT competition.Storage property liquid crystal cell receives much attention as high speed, jumbo display, become the research main flow, a large amount of reports all is the application of storage property liquid crystal cell in high speed, high capacity display, storage property liquid crystal cell is not seen that as the display of low speed, low capacity original research report is arranged, obviously be to it is believed that the demonstration of low speed, low capacity is too simple, the research of being unworthy spending a lot of time and energy.In fact, public demonstrations such as many application scenarios such as banker's rate board, goods tag, share quotation, its single capacity of display is also little, and does not need to upgrade fast, how dexterously application memory liquid crystal cell, the advantage of giving full play to its storage property still are worth research.

The objective of the invention is storage property liquid crystal cell is applied to the occasion that main flow research institute is ignored, propose a kind of will storage property liquid crystal cell as the driving method and the device of low speed, low capacity display, the advantage that makes full use of storage property liquid crystal cell reduces the cost of display significantly.

Content of the present invention is in fact to the further application of the bistable characteristic of liquid crystal cell photoelectric curve.The distinctive bistable characteristic of storage property liquid crystal cell is after stopping to apply driving voltage, and its displaying contents can be removed or upgrade to the displaying contents of liquid crystal cell can just up to applying driving voltage once more under stably preserving under zero electric field.The existing driving method that utilizes bistable characteristic is with a driver each row in the storage property liquid crystal cell to be carried out line by line (or interlacing) turntable driving.The invention is characterized in: drive a plurality of storage LCD one by one with a driver, so-called a plurality of display is meant that the locus separates each other and displaying contents can mutually different N (N is greater than 1) display, in N display each all has the P road output interface of P road input interface and driver adaptive, can carry out electric switching on and off at any time, but have only a display and driver to connect any time at most.

N display is to be connected by multichannel (P road) multidirectional (1 couple of N) electronic switch with first kind of electric connecting mode between the driving, the input port of electronic switch is connected to the delivery outlet of driver with P core cable at this moment, the control mouth of electronic switch is connected to the control circuit of driver, the N of an electronic switch delivery outlet is connected respectively to the input interface of N storage property LCD with N root P core cable, and this kind mode relies on control circuit commander electronic switch to come a driving N display one by one.The time that applies driving voltage foundation (or renewal) displaying contents on each display is very short, and the zero electric field that does not add driving voltage descends the time of preservation displaying contents then much longer.If applying the time of driving voltage on each display all is 1 Δ T, if driver continuous drive N display constantly, then each display does not add driving voltage and preserves the time of displaying contents and be (N-1) Δ T, common (N-1)＞＞1.Under many situations, a driver only needs a driving N display intermittently, horse back is closed driving power after opening driving power to drive a display update displayed content, opening driving power after a period of time again drives next display and closes driving power, under this interrupted type of drive, each display do not add driving voltage preserve the time of displaying contents again can be much larger than (N-1) Δ T.In this type of drive if multidirectional electronic switch of multichannel and Drive and Control Circuit are produced within the integrated circuit block, just become a driver that N group (every group of P road) delivery outlet is arranged, control circuit (comprising clock, storer, central processing unit and program and data input port etc.) is arranged in this driving.A driver drives N display like this can be considered as timesharing and drive a virtual big display by " OK ", each of the big display that this is virtual " OK " is exactly a storage property liquid crystal display cell, the N " OK " that is virtual big display fitly is arranged in parallel, but optionally separates each place in the space.

N display is to be connected by the mechanical type electric switch with second kind of electric connecting mode between the driver, just connect on the mechanical switch close, mechanical switch disconnects, and is to make driver and display spatially separate distance, and this moment, the electric nature of going up also opened circuit.The mechanical switch of N display input port should be the identical switches that can exchange of specifications and models, just can connect with the delivery outlet mechanical switch of same driver, the pattern of mechanical type electric switch is diversified, modal universal switch is the plug switch, form by plug and two kinds of plug connectors of socket, when using the plug switch, the driver delivery outlet connects a P core plug (or socket), and then N each input port of display all connects an adaptive P core socket (or plug).By plug (socket) is plugged on the different socket (plug), drive each display respectively.The plug switch has numerous product types can supply to select for use.Another kind of mechanical type electric switch is the spring stylus switch, constitute by contact pilotage showing plate and adaptive with it contact array plate, when using the spring stylus switch, the delivery outlet of driver connects the contact pilotage array board, the input port of N display all connects adaptive contact array plate, when needs drive certain display update displayed content, the spring stylus array board on the driver is pressed on the contact array plate of this display, with regard to renewable displaying contents.Because each driving required time is extremely short, can take away at a touch, it is very simple and convenient to get up with the spring stylus switching manipulation.Also having a kind of mechanical type electric switch is that conductive adhesive tape connects folder, it is by conductive rubber strip the input port of the delivery outlet of driver and display to be electrically connected to connect, and this moment, the electrode input port of storage property LCD needn't connect lead-in wire but more directly with liquid crystal cell ITO pin row on glass.The output electrode row of lcd driver should make identically with the ITO pin row shape of liquid crystal cell and pin is corresponding one by one, and on the output electrode row of lcd driver, the conductive adhesive tape and the folder that is located by connecting are installed, it is clipped on certain display, just can make between driver and this display and realize being electrically connected, drive this display update displayed content.Conductive adhesive tape connects folder ITO pin direct and that liquid crystal cell is on glass and links to each other, and having saved goes between again picks out the trouble of input port, once pressing from both sides connection, operates also simple.Except three kinds of electric beginnings of mechanical type of above recommendation, other mechanical type electric switch as the moving switch of plate, slide switch, rotating switch etc., all can adopt as long as can realize the changing-over of 1 couple of N.

A driver drives one by one to N display, the identification problem that has display, because the display contents of different displays is inequality, drive signal must be sat in the right seat, not filling perhaps, a drive signal that hat Lee is carried i display is added on j the display, therefore which display must have way at first to discern the display that is connected be to driver, and then the drive signal of this display of taking-up is put into working storage from storer, opens the drive signal impulse that drives in the amplifying circuit output working storage at last and upgrades its displaying contents to this display.In order to discern, each display all need add the identification code electrode, and the controller in the lcd driver just can be judged by the visit identification code and connect which display.In the switching of electronic switch recognition system has been arranged, lcd driver just only needs a scan N identification code under low-voltage, is the display that needs the update displayed content when recognizing, and just opens and drives amplifying circuit, the output high-voltage pulse writes, so not only fast but also power saving.There had recognition system also to make for manual switching of mechanical type electric switch to be much simple to operation, only needs lcd driver and each display bumped one by one to connect just.If no recognition system, numbering that then will artificial first read-out display, the digital keys of operating lcd driver again makes it to export the data pulse of this numbering and writes this display, and so not only troublesome poeration is also made mistakes easily.

The method that a kind of alternative recognition system is arranged is with the put in order coding of N display by the locus, be wired to successively

electronic switch

1,2 ... the N delivery outlet, at this moment needn't discern electrode in the display, the numbering of delivery outlet is exactly the code clerk of display on the electronic switch, therefore the numbering that each delivery outlet of electronic switch was originally just arranged in the control circuit can save the program of scanning identification coding of displays number.Desire is upgraded the display of which number, and the data that the electronic switch of directly opening this number is exported this number are rushed in row and write just, and this method is more simple, is the prefered method of recommending during with the electronic switch switching display.When with mechanical type electric switch craft switching display, should on display casing, put on code clerk by the spatial disposition order of display.Lcd driver is designed to both can export one by one in order the data pulse of N group, also keys available is selected certain group data pulse of output, need renewal just to adopt the method that connects in turn N display to write one by one when N display is all or most of, then select for use single renewal of way of artificial check mark to write when only needing to upgrade the minority display.

First embodiment of the present invention sees synoptic diagram 1, and N switches to electronic switch with the P road, makes a driver be connected respectively to N display.

Second embodiment synoptic diagram 2 of the present invention has the driver on N the every delivery outlet P of delivery outlet road to be connected to N display with one.Have only one to drive discharge road output P road high-voltage pulse in the driver, by the changeable any a bite that outputs to N delivery outlet of control circuit.

The 3rd embodiment of the present invention sees synoptic diagram 3, makes a driver switching be connected to N display with common P core plug switch and writes respectively.

The fourth embodiment of the present invention is seen synoptic diagram 4, switches with the spring stylus switch to make a driver be connected respectively to N display, and two pilot holes are arranged on the contact board, and two reference columns that cooperate are with it arranged on the contact pilotage plate.

The 5th embodiment of the present invention sees synoptic diagram 5, switches with conductive rubber strip switch folder to make a driver driving N display respectively.On the switch folder spring, location-plate and conductive adhesive tape are housed, location-plate guarantees the electrode pin aligning, and spring makes conductive adhesive tape be pressed on ITO automatically and upward guarantees to electrically contact.

Lcd driver of usefulness of the present invention drives the side of a plurality of storage liquid crystal displays Method and device take full advantage of liquid crystal cell and drive applying not adding between the driving voltage for twice The characteristic of storage displaying contents under the zero electric field during the moving voltage, it is from individual monitor Drive line by line and develop into the one by one driving of N display, thereby not only have power saving Advantage and also saved (N-1) individual driver, can reduce cost significantly the spy Not for the display as price label for goods in the department stores and so on, its displaying contents Renewal does not need very fast, and quantity (N) is again very big, can save (N-1) individual driver Economic effect be considerable. Method and apparatus of the present invention, first-selected recommendation courage steroid One nematic phase becomes the storage liquid crystal cell of pattern, the contrast height of this box, and the visual angle is wide, Display effect is good, is suitable for public demonstration, and shortcoming is the driving voltage height, so that driver Price is higher, but the quantity of driver of the present invention is reduced to 1, single valency height from N A bit, total price is all much lower, and is economically still worthwhile, so be suitable for commercial Application.

Claims

1, the device that drives of a kind of liquid crystal display, zero electric field can be stored the storage LCD of displaying contents down and the interface circuit between lcd driver and display and the driver is formed by stopping to apply behind the driving voltage, it is characterized in that: drive a plurality of storage LCD separated from one another with a lcd driver respectively in different time sections, the output interface of this driver can the electric respectively input interface that is switched to each display.

2, liquid crystal display drive unit according to claim 1, it is characterized in that: the input interface of a plurality of storage LCD is plug connectors of same specifications and models, the output interface of lcd driver then is a plug connector with matching, and it can be respectively be electrically connected with the plug connector inserting of each display.

3, liquid crystal display drive unit according to claim 1, it is characterized in that: the input interface of a plurality of storage LCD is the printed-wiring board (PWB)s with same electrical contact array, the output interface of lcd driver is a spring stylus array board that matches with it, and the pressing by contact pilotage plate and contact board can make driver and arbitrary display realize electric connection.

4, liquid crystal display drive unit according to claim 1, it is characterized in that: a plurality of storage LCD have identical ITO input electrode lead-in wire row, the output interface electrode row of lcd driver is corresponding one by one with the ITO input electrode lead-in wire row's of display arrangement position, on actuator electrode row, conductive adhesive tape is housed and the folder that is located by connecting, is used for being clipped in and realizes being electrically connected between driver and display on arbitrary display.

5, liquid crystal display drive unit according to claim 1, it is characterized in that: the input interface of N storage property LCD all is wired in the N group output of the multidirectional electronic switch of multichannel, the input electrode group of electronic switch is wired to the mouth of displacing of lcd driver, make the input electrode winding lead in N the output electrode group any one group by control circuit control electronic switch, realize that a driver drives a plurality of displays one by one.

6, liquid crystal display drive unit according to claim 1, it is characterized in that: the input port of N storage property LCD all is wired on the output electrode of a lcd driver, and each display can be regarded the zonule (local) in the virtual big display as.With the local wrting method that only upgrades some ranks content in the virtual big display, the display that makes the different location is one by one by a driver drives.

7, liquid crystal display drive unit according to claim 1, it is characterized in that: the input interface of a plurality of storage liquid crystal displays, electricity coding with this display of sign, has recognition control circuit in the lcd driver, after the input port of driver delivery outlet and certain display is connected, controller in the driver just can identify the coding of the display of being connected, and Control Driver output is corresponding to the electric pulse data of this coding displaying contents.

8, liquid crystal display drive unit according to claim 1, it is characterized in that: lcd driver is made up of parts such as driving circuit, controller, storer, input/output interfaces, a plurality of storage displays have coded address separately, the update time of each display and content are input in the driver in advance and are stored in the storer in the driver, controller can connect preset program and take out content and the unlatching driving amplifying circuit that upgrades from storer when the time comes, drive the display update displayed content of prescribed coding, close the driving amplifying circuit afterwards.Arrive another predetermined time, can drive another display update content in the same way again.