JPS59119320A - Liquid crystal display input and output device - Google Patents

Abstract

PURPOSE:To obtain a liquid crystal display device having digitizer functions by superposing an input board part formed by forming longitudinal and lateral transparent electrodes on a substrate with an insulating layer between upon a dot matrix liquid crystal display part formed by forming longitudinal and lateral transparent electrodes on an upper and a lower substrate and sandwiching a liquid crystal material. CONSTITUTION:A liquid crystal display input/output device consists of longitudinal transparent electrodes 2(13) for input detection which are formed on the glass substrate of the input board part with the insulating layer 14 between, lateral transparent electrodes 3(15) for input detection, longitudinal transparent electrodes 6 for display on the upper glass substrate 4 of the liquid crystal display part, lateral electrodes 7 for display on the lower glass substrate 5, an upper linear polarizing film 8, a liquid crystal layer, a liquid crystal sealing part 10, a lower linear polarizing film 11, and a reflecting plate 12. Scanning signals are applied to the longitudinal and lateral detection electrodes 13 and 15 in line order and a conductive pen is brought into contact to detect an input position. Consequently, the liquid crystal display device having digitizer functions is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a digitizer and a liquid crystal display device that allows handwritten input.

An object of the present invention is to provide a simple input means for a liquid crystal display device that is suitable for low power consumption type display, and to enable a hand belt digitizer display device and a handwriting display device for two-way communication. There is a particular thing. Also, in the same H・Personal'C
It is possible to toss an AD system.

Conventionally, a capacitive sensing type digitizer is well known as a digitizer capable of handwriting input, and a CRT scanning light detection system, so-called light pen, is also well known as a CAD system. However, both of these systems are complicated systems, large in size, and expensive.The present invention uses a liquid crystal display device as a display means, and displays the planar structure that liquid crystal originally has. The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a two-dimensional drawing of an example of the structure of the liquid crystal display input/output device of the present invention, in which an input board is placed exactly over one of the display panels. In the figure, 1 indicates the glass substrate of the input board section, 2 indicates a transparent electrode for vertical input detection, 6 indicates a horizontal transparent electrode for detecting human power, 4 indicates the upper glass substrate of the liquid crystal display section, and 5 indicates the lower glass. In the substrate, 6 is a vertical transparent electrode for display, and 7 is a horizontal transparent electrode for display. As is clear from FIG. 2, which is a sectional view of the structure of this embodiment, the human force detection electrodes 2, 3 and the display electrodes 6, 7 are arranged to overlap when viewed from above. That is, the dot matrix of the display line element and the detected dot matrix overlap.

As a result, the vertical and horizontal intersection dots of the detection transparent electrodes can be detected, and the picture elements below can be lit. This will be discussed in more detail later. In FIG. 2, 1 to 7 are the same as in FIG. 1, 8 is an upper linear polarizing film, 9 is a liquid crystal layer, 10 is a liquid crystal sealing part, 11 is a lower linear polarizing film, 12
is a reflector. In this example, a reflective field effect type liquid crystal display section is used, but it is also possible to use a transmissive type or a guest host type display section. Of course, it is possible to use a color display device, but in that case, a color filter is required, and a set of three primary color display pixels must be arranged so that one of the detection dots corresponds to the other. There is.

The configuration of the detection electrode will be explained in more detail with reference to FIGS. 6 to 5.

In Figure 5, 16 is a vertical transparent lightning pole for detection, 14
15 is an insulating layer, 15 is a horizontal transparent electrode for detection, 16 is a glass substrate, 17 in FIG. 4 is the position of a horizontal display electrode, 18
indicates the position of the vertical display electrode. Since the insulating layer 14 separates the vertical and horizontal electrodes and prevents false detection due to wraparound of position detection signals, it is necessary to make the insulating layer relatively thick and suppress the influence of capacitive coupling as much as possible. As described below, the input position is detected by applying a scanning signal to the vertical and horizontal sensing electrodes in line sequence, and then touching the signals with a special pen with a conductive tip. do.

Therefore, the surfaces of both the sensing electrodes 13 and 14 must be sufficiently exposed so that they can be easily contacted, but on the other hand,
To reduce the probability of accidentally touching adjacent sensing electrodes,
Appropriate space is required between the electrodes. Show this point!
In order to make the picture element as large as possible, it is desirable to narrow the gap between the electrodes to the limit of processing technology. The input position detection of the present invention detects an intersection point by contact and lights up the display picture element below it, so the shape of the intersection of the detection electrodes and the relative position with the display picture element are important. This prevents the picture elements from being turned on accidentally. FIGS. 5(a), (b), and (c) show three examples of how the shape of the intersection of the sensing electrodes and the relative position with respect to the display picture elements are set to desirable states.
This is an example.

As these examples show, contacting with a conductive pen on the sensing board opposite the center of the display picture element results in reliable contact with the vertical and horizontal lines of the sensing electrodes at the same time.

Figure 6 is an illustration of the tip of a conductive ηL pen for detection, including one with a structure with several thin lines sticking out, as shown in 19, and one with a conductive net at the tip, as shown in 20. Conceivable. Since the tip of these conductive pens is always in physical contact with the sensing electrode, the material and structure must have sufficient mechanical strength and be resistant to damaging the electrode.

In this respect, it is preferable to use conductive plastics, which have been widely used recently. These conductive pens are divided into types that require a lead wire to pick up the detection signal by wire, and types that simply short-circuit the vertical and horizontal electrodes, depending on the detection signal processing method, as will be described later.

FIG. 7 is an illustrative drawing of how the conductive pen comes into contact with the detection electrode on the human-powered board.

FIG. 8 is a diagram illustrating an example of the use of software effects when using the liquid crystal display input/output device of the present invention. 21
-23 all indicate display pixels, but 21 is an area where handwriting input is possible, 1) is a pixel that has not yet been input, and 22 is a pixel that has already been manually lit. o2
3 is a picture element used exclusively for display in the input-prohibited area even in the handwriting input use mode. The picture element 21 is driven to a half-lit state, so that the input possible area and the display-only area can be seen at a glance. For example, when the liquid crystal display input/output device of the present invention is used in a terminal of a two-way communication system using an optical cable, and it is possible to display input and output at the same time as the other party, the display area for signals from the other party is This is an effective method because it can prevent display confusion by dividing the input area so that it can be seen at a glance. That is, in the input mode of the input board section used as a digitizer, the input possible area is half-lit, and only the picture elements to which input has been received are fully lit. The advantage of this method is that you can see the half-lit pixels, so you can easily identify the location of the pixels you want to light up, and you can place the pen in the center of the pixels, which is very effective in preventing input errors. It is.

FIG. 9 shows an example of an input detection signal system, and FIG. 10 shows another similar example. Both Figures 9 and 10 are examples of the wired detection method, in which both the scanning signal of the vertical sensing electrode and the scanning signal of the horizontal sensing electrode are extracted 2 and the lighting position of the picture element is determined. be.

In this case, it is necessary to prevent the vertical and horizontal electrode scanning signals from overlapping at the same time, and in FIG. 9, the vertical scanning signals X1, X7 .・・・
・x? Signals of 25, 26, and 27 as L are applied to the vertical sensing electrodes. During the period from the x signal to the X2 signal, signals of 28, 29.30 as horizontal scanning signals YI+Y2+...Ym are applied to the horizontal sensing electrodes. Signal 61 is a timing signal for writing information picked up by a conductive pen from any of the signals X, ~Xfi into the memory as data, and signal 32 similarly writes Y, ~yt+' to the side memo IJ-. 1 is the timing signal. FIG. 10 shows a case where vertical scanning signals and horizontal scanning signals are alternately scanned, and 3
3 corresponds to X, 54 corresponds to x2, sg corresponds to X7+, 36
corresponds to Y, 37 corresponds to Y2.3B corresponds to Yga. In this example, if the number of electrodes on the X side is equal to the number of electrodes on Y
This is a timing signal for writing side position signal data into memory.

The processing circuit configuration is simply shown in Figure 11.41
is the human power part from the conductive pen, that is, the signal from the sensing electrode is input. A group of AND gates 42 to 44 determine whether the incoming signal matches any of X, to Xn, and 45 converts it into a BCD signal. In other words, the input to 45 is a manual signal of one input lead, where only X (where the lIll detection signal was located 7) and the pulse width time of the other scanning signals are level, and the rest are O level. This is converted into a BCD 17, and written to the memory 52 by the CPU 5 using the write timing signal '51 or 39.
1 is activated as an interrupt to perform memory writing. 46-4
49 is a BCD conversion circuit on the Y side, 50 data bus lines, 56 is a memory 52
control line. The operation of the CPU 51 is as follows:
It is broadly divided into One is a process of writing the signal after B c D exchange into the memory using a routine as illustrated in FIG. 12 during each scanning signal period. In other words,
Here, if there is no detection signal, the BCD output is 1
When considered in 0-base, it should be O, but considering the possibility of malfunction due to noise, it is determined that there is no detection signal when it is 0, and when it is larger than n on the Do not write to. In addition, if the data area Di on the X side and the data area Q on the Y side are secured in advance, and there is input from multiple sensing electrodes, that is, if the conductive pen is connected to the X side or two Y sides at once, It is necessary to process the memory in consideration of the above-mentioned cases of contact. The second operation of the CPU, as shown in routine 55, is interrupted by the -scan cycle signal 24 and processes the position data Di, Ql input during this scan period in a manner suitable for lighting up the liquid crystal display pixels. It is something to do. In other words, do not duplicate the position data of picture elements that are already lit in the memo IJ-, and if the position data of multiple picture elements are included in Di and Qt, pick up all the combinations. The goal is to eliminate lighting failures. The above-mentioned processing is performed every cycle, and the final lighting position data is collected at a predetermined location in the memory.The actual LCD drive circuit is well known, so I will not explain it here, but based on the memory information, the multiplex drive signal is Circuit processing will be performed. In practice, it may be necessary to rearrange the lighting position information in order of the smallest number on the Y side and further in order of the smallest number on the KX side.

FIG. 13 shows another example of this embodiment of the circuit, and is an example of a type in which the conductive pen is simply short-circuited between the X-side detection electrode and the Y-side detection electrode. 56 is a cycle signal that separates one cycle of the scanning cycle, and 57, 58, and 59 are sensing electrode scanning signals of Xl+2+xn>'so, 6
1.62 are timing signals for latching the XI + x2 + Xn signals, respectively.

Figure 14 shows an example of this circuit. ・63, 64゜65 are the input lines from the detection type t'fi Y+ l 2 1 '' on the Y side, and each has the same number of latches as the electrodes on the X side @η. Wire gate groups 69 to 77. 66° 67.68
is signal 60. -61, 62 application terminals, if Y
When the detection electrodes No. 2 and X are short-circuited by the conductive pen, the signal is latched by the latch gate 72 when Xl is scanned.

78 to 80 are memories corresponding to each ym. By applying a cycle signal to the write line 81, the picture element position data latched for each cycle is stored in the memory. This memory can be turned on by using the cent reset method. Data can be entered one after another. If you want to erase a part of a pixel that has been burnt, this circuit example cannot handle it, but you can install an external switch to set the partial erase mode, and connect the centricent in reverse in the - line erase mode. Please try to input it.

If you do this, you can easily delete a portion of it. In the example of FIG. 14, the conductive pen is simple, but the circuit tends to be larger than that of FIG. 11, and which one is more economical depends on the total number of picture elements.

FIG. 15 is an image diagram of a handwritten kanji practice device made by applying the present invention. A liquid crystal display input/output device 83 with 90×90 pixels is mounted on the main body 82, and has operation keys 84 for inputting kana characters, stroke order, abbreviations, broken characters, etc. In this example, the typeface still doesn't look natural, but the number of picture elements is reduced to 2.
By increasing the size to about 00x200, it is possible to make a calligraphy practice device using a brush made of thin metal wires.

The liquid crystal display input/output device of the present invention has been described above, including application examples. However, the present invention makes it possible to create a liquid crystal display system having a digitizer function with a relatively simple configuration.
The effect of use is great.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a configuration example of a liquid crystal display input/output device according to the present invention, in which 1 is a glass substrate of an input board section, and 2 and 3 are transparent electrodes for detection. FIG. 2 shows a cross-sectional structure, and the liquid crystal layer 9 is driven by 6.7 electrodes. - Figures 6, 4, and 5 are all enlarged views of the transparent chamber for detection, the poles i3 and 15, and the insulating layer 14 that separates them, and their relative positions with respect to the display pixels are also shown. (7) Figure 6 is an illustration of an example of the tip structure of a conductive pen for handwriting input. Figure 7 is an illustration of a contact image during input. 8 is a display pattern diagram illustrating an example of a devised display method when used in handwriting input mode. FIG. 959 and FIG. This is a signal diagram of each part to explain the circuit configuration of the system, and Fig. 11 is a block diagram of an example of a detection circuit. Fig. 12 shows a simple processing routine when a position detection signal is processed by ○pu. FIG. 13 is a signal diagram of each part explaining another embodiment of the circuit configuration, and FIG. 14 is a block diagram of another embodiment of the detection circuit. The product image when the present invention is applied to a kanji practice device is shown.

Claims (1)

[Claims] 1. Forming vertical and horizontal transparent electrodes on a glass substrate under the go7,
A dot matrix liquid crystal display section consisting of a liquid crystal material sandwiched between both electrodes, another vertical and horizontal transparent electrodes formed on a sixth glass substrate, and an input electrically separated between these latter IT electrodes by an insulating layer. A liquid crystal display input/output device comprising a board section. 2. The liquid crystal according to claim 1, wherein the area of the overlapping portion of the vertical and horizontal electrodes of the input board section is smaller than the pixel area formed by the vertical and horizontal electrodes of the dot matrix liquid crystal display section. Display input/output device. (b) The overlapping parts of the vertical and horizontal electrodes of the input board section are the above-mentioned donotomas. The liquid crystal display input/output device according to claim 1, wherein the input board section is stacked on top of the liquid crystal display section.