JPH06511095A - How to address matrix-aligned liquid crystal cells - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] A method of addressing a matrix-aligned liquid crystal cell Regarding the method of addressing crystal cells, there are some specific, but not unique, methods. ＼Regarding cells used for things such as display devices.

One known method of addressing a matrix-aligned liquid crystal cell is the 11K Pat ent Nu+wber GB 2,173,336B . In this method, the cell is defined as a matrix of orthogonal rows and columns of electrodes. It is processed. Individual elements can be selectively switched to a dark (no light transmitted) state or A waveform is applied to the rows and columns to create a state in which light is transmitted.

There are two types of data on the column electrodes: "on" if "unchanged" (unc). (hanged) waveform is applied. In synchronization with this waveform, the row electrode is marked with “selection J ( select), "non-select" and "blank" (blank) waveform is applied. "Select" to only one row electrode at a given time a waveform is applied, and a "blank" waveform is applied to at least one other row electrode. . “Non-selected j waveform is applied to all other row electrodes.

The configuration described above operates as follows. Data waveforms are applied to column electrodes and selected A waveform is applied to create the desired pattern on the row electrodes. In this configuration, this The electrode is blanked by a planking waveform applied to it. Ru. This configuration has the effect of setting the row electrodes to a dark (or off) waveform. This electric regardless of whether the pole is mixed with a ``1 on'' or ``non-changing'' data waveform. All of the display elements common to the row electrodes are in the dark state before the selection waveform is applied to the row electrodes. Switched.

At the same time as the data waveform is applied, a blank waveform is applied to the row electrodes. Kaichirushi The need for DC compensation and charge balancing in the stem, i.e. The need for a "non-changing" data waveform to have no DC component is obvious to those skilled in the art. That is.

However, the system exemplified by CB 2,173,336B has a planking waveform. When the selection waveform is applied to a row electrode immediately before being applied to the same row electrode, the The drawback is that the response time is slow. must be secured before a crisis occurs. Must be.

An object of the present invention is to provide an address configuration that at least reduces the delay in liquid crystal response time. There are many things. One According to the present invention, it is possible to address a matrix-aligned liquid crystal cell containing a ferroelectric liquid crystal material. the cell comprises a first electrode center member on one side of the material and a first electrode center member on one side of the material; a second electrode set member perpendicular to the first electrode center on the other side of the material; The image of the array contains multiple pixels defined by an overlapping area between In the way that the elements are accessed on a line-high-line basis after planking , a monopolar blanking pulse is applied to the first electrode cent part for blanking. a unipolar selection pulse is applied to the first material and for selectively addressing the pixel. A bipolar data pad is applied in series to the electrode center member of the pulses are applied in parallel to the second set, and the positive-going portion of the data pulses is 1 synchronized with the selection pulse for one data meaning, the negative-going portion of said data pulse; The selection and blanking pulses are synchronized with the selection pulses for other data meanings. The polarity of is opposite and unchanged, and the blanking pulse has magnitudes v s / n and The period mT, where ■ is the selection pulse voltage, T is the time length of the selection pulse, n and m is m greater than or equal to n, and any given blanking Any set pulse amplitude is less than that of any selected pulse. A method of addressing a matrix-aligned liquid crystal display is provided.

Thus, the present invention provides a blank whose amplitude and duration are deformed within the desired operating range. By using the king pulse, the potential for the response time of the liquid crystal material can be determined. Addition of matrix array type liquid crystal cell with reduced slowdown provide a response method.

An embodiment of the invention is illustrated by way of example in the drawings.

FIG. 1 shows the structure of a conventional matrix array cell, and FIG. 2 shows the structure of the conventional cell and the structure of the present invention. shows graphs of various waveforms applied to the row and column electrodes for both; Figure 3 graphically shows a comparison between the general shape of the blanking waveform and the selection waveform. That's why Is Figure 4 related to the present invention? The modified blanking waveform generated in the cell is shown graphically. and FIG. 5 shows the relationship between applied voltage and time for selected pixels.

Referring first to FIG. 1, there is shown a general matrix generally designated as 2. A box-aligned liquid crystal cell is shown, the cell comprising a liquid crystal material (not shown). contains an array that overlaps orthogonal row 4 and column 6 arranged between .

Also shown in FIG. 2 is the operation during the addressing of cell 2.

The general operating principles applied to commonly known liquid crystal displays are based on this invention. It should be recognized that this also applies to explicitly mentioned displays. Therefore , the data signal applied to the column electrode 6 has a "non-changing" waveform 8 and an "on" waveform 1. O comes out. The row electrode 4 waveform applied in synchronization with the column electrodes 8 and 1o is "selection" 12, " 14 "non-selected" and 16 "blank" waveforms. Figure 2 (a), (b), (c ), (d) are the resulting row and column voltages mixed with the selection waveform applied thereto. This is a composite waveform at the intersection of poles 4°6.

A cell defined by the overlapped area between row electrode 4 and column electrode 6 The way to address one particular pixel 3 in cell 2 is as follows: Row 4, of which one special pixel forms part, before addressing with indication data 2 must first be set to the dark state. This is the blanking waveform 1 there This is achieved by applying 6. This is a state in which all rows 4 are predetermined It is necessary to ensure that the display data is set to This is because that.

The desired display data waveform 8 or 1o, for example 8, crosses or overlaps the pixel 3. voltage is applied to the desired column electrode 8 for lamp lamp. At the same time, pixel 3 and overlay A selection waveform 12 is applied to the corresponding electrode 4. Especially with reference to Figure 2(a) , the combination of unchanged waveform 8 and selected waveform 12 at pixel 3 is a special mixture. It can be seen that a composite waveform is created. Similarly, if the on waveform 1o is an unchanged waveform 8 is selected instead, the composite waveform at pixel 3 is as shown in Figure 2(b). Become.

In any case, the row electrodes 8 overlaying the pixels 3 are addressed as described above. At the same time, the electrode for the desired next row to be addressed (the next row is in the array (although not necessary) is a blanking waveform in preparation for the address as shown above. Receive 16.

The voltage amplitude shown in Figure 2 is ■, the voltage of data waveforms 8 and 1o, and T is the voltage amplitude. It should be understood as the duration of the waveform. Similarly V.

is the amplitude of the selection waveform 12; 5 is the amplitude of the blanking waveform 16.

However, in reality, in the conventional technology, the blanking pulse is simply applied to the electrode for the next row. What displays undesirable results when the address period is applied only before the selected waveform If this happens, the response time of the liquid crystal will be slow and the temporal width T of the waveform will not be able to fully display the function. and as illustrated by this example, as shown in FIG. As described above, the present invention solves this problem without slowing down the response time of the LCD. By providing a blanking waveform 16 that is temporarily applied next to the waveform 12, lightening can be achieved. It has been decreasing.

This is achieved by modifying the shape of the blanking pulse 16. this strange The shape reduces the amplitude of the blanking pulse 16 and increases it to the amplitude of the next selection pulse 12. ■Achieved by making it smaller than 8.

However, the period of this blanking pulse 16 is longer than the period of 1H)J(pulse 12). It is preferable that the

However, if the areas defined by selection 12 and blanking pulse 16 are equal, Although it is not essential that the area defined by the selection pulse be It is desirable that it is not smaller than that of the king pulse.

The above is shown in FIG. In FIG. 3, the blanking pulse 16 has an amplitude of ■5. Compared to the selection pulse 12 whose duration is T at can be seen. In this example m=n=2.

The reduction in the amplitude of the blanking waveform 16 has advantages as previously stated. This can also be explained by looking at FIG. Figure 5 shows the switching characteristics of cell 2. is a plot of the relationship between the applied voltage and the time during which this voltage is applied. It is. The magnitude of the blanking pulse 16 generally sends each pixel 3 into the dark state. It is well known to those skilled in the art that this is often larger than is actually necessary.

For this purpose, a relaxation period immediately following the application of the blanking pulse is used to generate the address. required before. Thus, in accordance with the present invention, the amplitude of the blanking waveform 16 is Reducing the width also eliminates relaxation periods within the switching boundaries of FIG. There remains a need to

The amplitude reduction and temporal expansion limit of the blanking waveform 16 requires: V, /n>V= It is understood that it is managed by

In principle, any value can be used for n and m, but integer values are convenient. I understand. It is not necessary that n and m be equal, but m must be greater than or equal to n. No.

However, if n and m are chosen equal, then the value is greater than or equal to 2. Preferably, the amplitude of the blanking waveform 16 is less than 2. This is because the period and period approach the case of FIG. 1(a) in which switching does not occur.

Finally, referring also to FIG. 4, it also shows the blanking pulse 16 according to the invention. A typical waveform that appears at pixel 3 when addressed is shown. This diagram is requested V s / n > V 4, if blanking pulse 16 When the amplitude V/n becomes less than V, the blanking period occurs when the voltage changes polarity. There is a period in between, and this change in polarity creates the desired blank (or dark) state. This is because it causes switching in the opposite direction away from . Thus limited V, / n>V.

exists.

The amplitude of blanking pulse 16 may be greater than that of data pulse 8.10. It will be appreciated that the values must be equal to or equal to each other. Therefore blanking During application of pulse 16, blanking pulse 16 and data pulse 8 or 10 The difference between the blanking pulses 16 and the opposite polarity does not occur.

Thus, the present invention provides a matrix array type liquid crystal cell with a modified blanking waveform. of the liquid crystal, thereby preserving the response time of the liquid crystal.

In the present invention, the pixels between the blanking pulse 1G and the selection pulse 12 are The number of lines can be eight or less.

For the embodiments described above, it is within the scope of the present invention to Deformations and changes are possible for the blanking that occurs to leave the bright state. It is obvious to those skilled in the art that this is possible.

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Claims (7)

[Claims] 1. A method of addressing matrix-aligned liquid crystal cells containing ferroelectric liquid crystal materials. so that the cell has a member of the first electrode set on one side of the material and the other part of the material. There is an opening between the member of the second electrode set orthogonal to the first electrode set on one side. Contains multiple pixels bounded by an area that overlaps, and the pixels of the array are blank. In a way that is accessed on a line-by-line basis after king, unipolar bra A blanking pulse is applied to a member of the first electrode set for blanking. and a unipolar selection pulse is applied to said first electrode set for selective addressing of pixels. A charge-balanced bipolar data pulse applied in series to the a second set of data pulses is applied in parallel, and the positive-going portion of said data pulse is one data pulse. synchronized with the selection pulse for the meaning of the data pulse, and the negative direction part of the data pulse is The polarity of the selection and blanking pulses is reversed. pairwise invariant, the blanking pulse has a magnitude Vs/n and a duration mT, where Vs is the selection pulse voltage, T is the time length of the selection pulse, and n and m are m greater than n. If the amplitude of any given blanking pulse is greater than or equal to What will be any value you set, to be less than that of the selected pulse? Characteristic address method of matrix array type liquid crystal display. 2. Since n and m are equal and the selection and blanking pulses are equal, A charge bar is attached to each member of the first electrode set by an area defined by a 2. A method according to claim 1, characterized in that a lance is maintained. 3. Claim 1 or Claim 2, wherein n and m are integer values. the method of. 4. 4. Method according to claim 3, characterized in that the values of n and m are 2. 5. 2. The method of claim 1, wherein m is granted a value greater than n. 6. 6. A method according to claim 5, characterized in that n and m have integer values. 7. The blanking pulse triggers the selection pulse for a given line of pixels in the array. The number of lines between the blanking and selection pulses is less than 8. A method according to any of the preceding claims, characterized in that: or equal to: