JP2916894B2 - Address device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data element addressing device using an ionizable gas.

[0002]

2. Description of the Related Art Systems using a data storage device include, for example, a video camera and an image display device. Such systems write data to storage elements,
It has an address device for reading data from now on. An apparatus of this type that is particularly relevant to one embodiment of the present invention is a general purpose flat panel display, the storage element or display element of which stores light pattern data. Flat panel displays include a number of display elements arranged in a viewing area on a display surface. Flat panel displays are desirable because they do not require a cathode ray tube to form the displayed image. This is because the cathode ray tube has a large shape, is easily broken, and requires a high voltage driving circuit.

One type of flat panel display employs an address device in which a large number of liquid crystal cells or display elements are arranged and multiplexed directly. Each of the liquid crystal cells is disposed between a pair of conductors, and these conductors selectively apply a selection voltage signal and a non-selection voltage signal to the liquid crystal cell, and change the optical state of the liquid crystal cell. Thereby, the luminance can be changed and an image can be formed. Display devices of this type can be said to be "passive". This is because "active" electrical elements do not cooperate in changing the electro-optical properties of the liquid crystal cell. Such display devices have the disadvantage that the number of address lines for providing video information, ie, data, used to form the display image is limited (eg, about 250).

As a measure for increasing the number of data address lines of a liquid crystal display device, a separate electric element cooperating with each liquid crystal cell requires an electro-optical response of the liquid crystal cell to a selection voltage signal and a non-selection voltage signal. Is to use an addressing device that corrects the substantial non-linearity of the address. Some of the "two-terminal" element addressing techniques are characterized by this method. Increasing the substantial non-linearity of the display element increases multiplexing capability in binary display, but there are many difficulties in achieving gray scale with this technique.

[0005] To obtain a liquid crystal matrix display with sufficient gray scale performance requires an addressing device that does not rely on obtaining a non-linear function from the liquid crystal material. To accomplish this, addressing devices using a matrix of electrical "active" elements employ electronic switches that are separate from the liquid crystal material for each pixel. This active matrix is
The required non-linearity and insulation of the display element are obtained by using a two- or three-terminal solid element associated with each liquid crystal cell. An address device constituted by a two-terminal element can use various types of diodes, and an address device constituted by a three-terminal element can use various types of thin film transistors (TFs) made of different semiconductor materials.
T) can be used.

[0006]

One of the problems with two-terminal or three-terminal active elements is that the very large number of active elements makes it very difficult to produce large numbers of matrices at high yields. is there. Another problem, particularly with respect to TFT devices, is that it is difficult to manufacture thin film transistors with sufficiently high "off-resistance". If the "off resistance" is relatively low, the display element cannot hold the charge generated there for a predetermined time. Further, at this time, the ratio between the “off resistance” and the “on resistance” decreases. This ratio is preferably greater than 10 for the proper operation of the TFT matrix. TF
The T matrix sometimes employs separate storage capacitors (capacitances) with each display element to eliminate the effect of "off resistance" not being sufficiently high. However, with the use of a separate storage capacitor, the cooperating TF
It seems that the T matrix becomes more complicated and the yield decreases. Another potential problem with TFT active matrices is that the need to come from the "on" current makes the TF
Since the size of the T element tends to be large, the size of the TFT is relatively large as compared with the size of the display element. This affects the light efficiency of the device.

[0007] The active element made by the TFT element is
It has the ability to form black and white and color images. To form a color image, the active matrix uses a color filter that is spatially aligned with the display element and contains many groups of spots of different colors. Thus, a group of display elements aligned with differently colored spots thus forms a single image pixel.

[0008] The flat panel display device can be implemented by using a display element using ionized gas or plasma, and forms a light emitting region of a color determined by what kind of gas is used on a display surface. These light emitting areas are selectively driven to form a display image.

Other flat panel display devices employ plasma that emits electrons, and these electrons are accelerated and collide with a phosphor to generate a bright spot. Although such a flat panel display device has improved luminance efficiency, it is difficult to form a wide display surface, and a complicated drive circuit is required. Such flat panel displays can be composed of phosphors excited by electrons with different spectral characteristics to form a multicolor image.

[0010] Gas plasma flat panel displays are intentionally mitigated by using a plasma-sac type gas discharge display. In such a display device, the plasma sack generated on the cathode side of the insulator provided with the opening moves from one opening to another opening and affects raster scanning. The production process of this plasma sack type gas discharge display device is complicated, and the yield is likely to decrease.

An object of the present invention is to provide an address device which can be manufactured at low cost and with high yield. It is another object of the present invention to provide an addressing device that uses ionized gas to write or read data to or from a data storage element (storage element). It is still another object of the present invention to provide an addressing device for an electro-optical device having a high addressing speed and high contrast characteristics. It is yet another object of the present invention to provide an addressing device that is capable of addressing portions of the dielectric layer in cooperation with ionized gas.

[0012]

According to the present invention, there is provided an addressing apparatus comprising a plurality of first devices formed on one main surface substantially in parallel with each other.
A first substrate having electrodes; and a plurality of groove-shaped recesses formed on the main surface opposite to the main surface of the first substrate and intersecting with the first electrodes and substantially parallel to each other and filled with an ionizable gas. A second substrate having; a second and a third electrode formed in each of the plurality of groove-shaped recesses on the main surface of the second substrate and substantially parallel to a longitudinal direction of the groove-shaped recess; And a dielectric layer provided between the second substrate and the dielectric layer and the second substrate
The dielectric layer can be ionized in the groove
A dielectric material layer for shielding from various gases; a first electrode and a third electrode
A first signal applying means for selectively applying a first signal between the electrodes; and a second signal applying means for selectively applying a second signal between the second electrode and the third electrode. A second signal is selectively supplied between the second electrode and the third electrode to ionize a gas in the groove-shaped recess having the second electrode and the third electrode that has received the second signal. Then, the portion of the dielectric layer corresponding to the intersection of the groove-shaped recess containing the ionized gas and the first electrode to which the first signal is selectively supplied is addressed.
Further, in the address device of the present invention, a plurality of adjacent groove-shaped recesses (N is an integer of 2 or more) are set as one set, and the second electrodes of the corresponding groove-shaped recesses of different sets are commonly connected, The third electrodes in the N groove-shaped concave portions are commonly connected to each other in each set .
The second signal applying means sequentially applies the first strobe signal to each set of commonly connected third electrodes, and applies the first strobe signal commonly to the third electrodes in the groove-shaped recesses of each set. During this period, a second strobe signal is sequentially applied to each second electrode in each set of groove-shaped concave portions.

The first embodiment of the present invention is an address device for a high-resolution flat panel display device used for either a direct-view type or a projection type. This display device includes a display panel constituted by display elements which are data storage elements arranged over the entire visual area. Each display element includes one in which a predetermined amount of an ionizable gas such as helium is sealed, and one in which a predetermined amount of an electro-optical material such as nematic liquid crystal is sealed, and the display elements are provided in cooperation with each other. Modulate the light that propagates through the electro-optic material where it is and emits outward.

A second embodiment of the present invention is an address device for a memory device, in which analog information is electrically written or read. The memory device includes a data storage element (storage element) or an array of memory elements, each of which is an ionizable gas such as helium, a dielectric material such as glass, plastic, and the like. A photoconductor (photoconductive material layer) is included. The ionizable gas and the dielectric material cooperate to provide a method of addressing the memory element to read a signal previously written to the memory element in some manner.

[0015] In both embodiments, the storage elements are arranged in rows and columns. In the first embodiment, the rows represent one row of video information or data; in the second embodiment, the rows represent two sets of discrete amounts of analog information or data. (In each embodiment, the information addressed is referred to as "data"
I will call it. ) The column electrodes receive the data, and the data strobe circuit addresses the column electrodes row by row by row scanning.

The display panel according to the first embodiment or the memory device according to the second embodiment includes first and second substrates which are spaced from each other and face to face. A number of non-overlapping conductive paths extending in a first direction along the inner surface of the first substrate form column electrodes for data drive signals applied thereto. A number of non-overlapping grooves (groove-shaped recesses) carved inside the second substrate extend inward along a direction substantially transverse to the first direction. This first and second
Are preferably the vertical direction and the horizontal direction, respectively. The reference voltage electrode and the row electrode are electrically insulated from each other, extend along the longitudinal direction inside each groove, and receive a data strobe signal applied thereto. Each groove is filled with an ionizable gas.

In the display panel of the first embodiment, a layer of a material having electro-optical properties and a layer of a dielectric material are disposed between the inner surfaces of the first and second substrates. The overlying dielectric material layer forms a barrier between the layer of electro-optic material and the ionizable gas. The shape of the display element is determined by the area where the column electrode and the groove overlap, and appears as a spot on the display screen. The spots are small enough and close together that they are indistinguishable under normal viewing conditions.

The display panel is constructed as described above, and the gas that can be ionized for each display element is in a conductive plasma state and a non-conductive ionized state in accordance with the applied data strobe signal. It functions as a switch that electrically switches between a non-existent state and a non-existent state. The strength of the data drive signal of the column electrode corresponds to the brightness of the display image.

Whenever the device is conducting, the region of ionized gas allows a data voltage representing the voltage of the data drive signal to be applied to the liquid crystal material region. The liquid crystal material region is spatially aligned with the ionized gas region. Whenever the device is non-conducting, the region of non-ionized gas allows the spatially aligned region of the liquid crystal material to hold the voltage across it for a predetermined time. The ionizable gas therefore serves to select the data stored in the liquid crystal material, thus providing a gray scale luminance display.

By switching the ionizable gas between the conducting state and the non-conducting state in the display panel, the light passing through the display element can be modulated. The transmitted light is
It depends on the strength of the applied data drive signal. A monochrome or black-and-white display device having a gray scale luminance function can be used for the display panel. A full-color display device with controllable color intensity can be realized by placing a color filter containing a group of spots of the three primary colors spatially aligned with the display element in a monochrome display device. . The group of three display elements that are aligned to form a group of spots will be one image pixel of a color determined in relation to the intensity of the spots in this group.

A display device using the addressing device of the present invention is capable of providing an entirely dynamic, gray-scale image over a wide range of field rates, providing a high quality display. This display device is particularly advantageous because of its simple and uneven structure.
At a field rate of 60 Hz on the display screen, at least 3000 data lines can be addressed.

In the memory device according to the second embodiment using the address device of the present invention, only one dielectric material layer is provided between the first and second substrates.
The shape of the memory element is determined by the region where the column electrode and the groove overlap. Because the memory device is shaped as described above, for each memory element, the ionizable gas is an electrical switch that switches between a conductive state and a non-conductive state in response to an applied data strobe signal. Function as a typical switch. The amplifier supplying the data drive signal functions as an amplifier for driving the column electrodes during the data write mode, and functions as an amplifier for detecting the column electrodes during the data read mode.

Whenever the device is conducting, the region of ionizable gas allows a data voltage with a predetermined intensity to be applied. This voltage represents the strength of the data drive signal generated in the dielectric material in the region spatially aligned with the region of the ionized gas.
This represents the data write mode of the memory device. Whenever the device is non-conducting, the region of the non-ionized gas allows the spatially aligned region of the dielectric material to hold the voltage applied thereto for a predetermined time. . The column electrode sense amplifier, which is the sensing means associated with this region, applies a reference voltage to the surface of the layer of dielectric material opposite the surface that is spatially aligned with the region of the ionized gas. When returning to the conducting state,
The region of the ionized gas changes the voltage applied to the dielectric material. This change is proportional to the previously written data voltage and appears at the output of the column electrode sense amplifier. This indicates a data read mode of the memory device.

By making some changes to the above addressing device, other means for applying data voltages to the memory elements of the memory device can be employed. For example, if a photoconductive material is used instead of a dielectric material and a light transmissive column electrode is used, incident light is proportional to its intensity,
The intensity of the data voltage applied to the memory device can be modulated. Such an addressing device could be used as a part of an image sensor or an optical processing device.

Other objects and advantages of the present invention will become apparent from the following description with reference to the drawings.

[0026]

FIG. 1 is a diagram showing a schematic configuration of a general flat panel display device 10 using an address device of the present invention. Referring to FIG. 1 and FIG. 2 showing details of the panel, the flat panel display bag holder 10 includes a display panel 12 having a display surface 14. This display surface 14
Includes a pattern of a rectangular planar array of display elements 16 which are individual data storage elements, that is, storage elements, which are separated from each other at predetermined intervals along the vertical direction and the horizontal direction. Each display element 16 in this arrangement is an overlapping intersection of thin and narrow electrodes 18 arranged in a vertical column and elongated grooves 20 arranged in a horizontal direction. In addition, the groove 20 becomes a groove-shaped concave portion as can be seen from the drawing. (Hereinafter, the electrode 18 will be referred to as the column electrode 1
Let's call it 8. The display element 16 in each groove 20 corresponding to a row) represents one row of data.

The width of the column electrode 18 and the width of the groove 20 determine the size of the display element 16, which is substantially rectangular. Column electrode 18
Is disposed on the main surface of the first substrate that is non-conductive and optically transparent, and the groove 20 is carved on the main surface of the second substrate that is non-conductive and optically transparent. This will be described later in detail. One skilled in the art will appreciate that in systems such as direct-view or projection-type reflective display bags, either substrate may be optically transparent.

The column electrode 18 receives a data drive signal of an analog voltage generated on a parallel output conductor 22 'by each one of the output amplifiers 22 of the data driver 24 (see FIGS. 2-6). The data driver 24 and the output amplifier 22 constitute a first signal applying unit. Groove 20
Receives a data strobe signal of a pulse voltage generated on a parallel output conductor 26 'by a respective one of the output amplifiers 26 of the data strobe circuit 28 (see FIGS. 2-6). The data strobe circuit 28 and the output amplifier 26 constitute a second signal applying unit. A reference electrode 30 (FIG. 2) passes through each groove 20, and a reference voltage (ground voltage) common to each groove and the data strobe circuit 28.
Is applied to the reference electrode 30.

In order to form an image over the entire display surface 14, the display device 10 includes a scanning control circuit 32. This adjusts the function of the data drive circuit 24 and the data strobe circuit 28 to sequentially address all columns of the display elements 16 of the display panel 12 from row to row. Different types of electro-optic materials may be used for the display panel 12. For example, as this material, the incident light 33 is used.
If a material that changes the polarization state is used, the display panel 12 is placed between the polarizing filters 34 and 36 (see FIG. 2). The filters 34 and 36 correspond to the display panel 1
2 and changes the brightness of the light passing through them.
If a liquid crystal cell that scatters light is used as the electro-optic material, the polarizing filters 34 and 36 are not required. Although not shown, a color filter may be disposed in the display panel 12 to form a multicolor image whose color intensity can be controlled.
For projection display, colors may be formed by using three separate single color panels. In this case, each panel controls one primary color.

Referring to FIG. 2 to FIG.
Comprises addressing means, which is separated by an electro-optic material layer (dielectric layer) 44 such as a nematic liquid crystal and a thin dielectric material layer (dielectric layer) 46 such as glass, mica or plastic. A roughly parallel one
A pair of electrode structures 40 and 42 are included. Electrode assembly 40
Comprises a dielectric substrate 48 made of glass, on which a column electrode 18 made of an oxide of indium and tin is provided.
0 is provided by vapor deposition. It is optically transparent and forms a strip pattern. Adjacent column electrodes 18 are separated by a spacing 52 and define a horizontal spacing between adjacent display elements 16 on a row.

The electrode assembly 42 is made of a dielectric substrate 5 made of glass.
4, the inner surface 56 of which is provided with a plurality of grooves 20 having a trapezoidal cross section. The depth 58 of the groove 20 is measured from the inner surface 56 to the bottom 60. Groove 2
0, a pair of thin and narrow nickel electrodes 30 and 62 extending along the bottom 60 and an inner surface 5 from the bottom 60.
6, there is a pair of side walls 64 extending divergently.
The reference electrode 30 of the groove 20 is connected to a common reference voltage. This is fixed to the ground potential as shown. The electrode 62 of the groove 20 is connected to the data strobe circuit 28.
Output amplifiers 26 (three and five of these are
And FIG. 3 respectively. ) Are connected to different ones. (The electrode 62 is hereinafter referred to as a row electrode 62.) To ensure that the addressing means operates, the reference electrode 30 and the row electrode 62 are connected to the display panel 12 as shown in FIGS. 4, 11A and 11B. On the opposite side, they are connected to the reference potential and the output 26 'of the data strobe circuit 28, respectively.

The adjacent side wall 64 of the adjacent groove 20 is
Reference numeral 6 denotes a support structure 66 that supports the dielectric material layer 46. The adjacent grooves 20 are spaced from one another by a width 68 at the top of each support structure 66. This width 68 determines the vertical distance between adjacent storage elements 16 in a column. The portion 70 where the column electrode 18 and the groove 20 overlap each other becomes the storage element 16, that is, the storage element, as shown in FIGS. FIG. 3 more clearly shows the arrangement of the storage elements 16 and their horizontal and vertical distances.

The gap 52 for insulating adjacent column electrodes 18 is determined according to the magnitude of the voltage applied to the column electrodes 18. Spacing 52 is typically much smaller than the width of column electrode 18. The width 68 is determined according to the inclination of the adjacent side wall 64 of the adjacent groove 20. Width 68 is typically much smaller than the width of groove 20. The width of the column electrode 18 and the width of the groove 20 are typically the same and are a function of the desired image resolution. This depends on the application to the display. It is preferable that the gap 52 and the width 68 be as small as possible. In the current model of the display panel 12, the groove depth 58 is half the width of the groove.

Each of the grooves 20 is filled with an ionizable gas, which preferably includes a helium gas, as described below. Dielectric material layer 46
Functions as an insulating barrier layer between the ionizable gas contained in the groove 20 and the layer 44 of the liquid crystal material. If the dielectric material layer 46 is not provided, the liquid crystal material may flow into the groove 20, or the ionizable gas may contaminate the liquid crystal material. Dielectric material layer 46 may not be needed in displays employing solid or encapsulated electro-optic materials. The principle of the operation of the display panel 12 is as follows: (1) Each display element 16 functions as a sampling capacitor for an analog data voltage applied to a column electrode 18 forming a part of the display element. (2) The ionizable gas functions as a sampling switch.

FIG. 6 is an equivalent circuit for explaining the operation of the display device 10. 6, each of the display elements 16 of the display panel 12 can be considered as a capacitor 80 (hereinafter, referred to as a capacitor model 80). This top plate 82 represents one of the column electrodes 18. Also, its bottom plate 86 represents a free surface 88 (FIG. 2) of the dielectric material layer 46. Capacitor model 80 represents a capacitive liquid crystal cell formed by the overlap of column electrode 18 and groove 20. The operation method of the display device 10 will be described using the capacitor model 80.

According to the basic address procedure, data
Driver 24 captures the first line of data. The captured data represents discrete values of the voltage of the time-varying analog data signal sampled at predetermined time intervals. The sampling of the intensity of the data signal at a particular event within this time interval is performed by the capacitor model 8 at the corresponding column position of the row electrode 62 receiving the strobe pulse.
It represents the intensity of the analog voltage applied to 0. The data driver 24 generates an analog voltage at its output amplifier 22 and applies it to the column electrode 18. In FIG. 6, four representative output amplifiers 22 of a data driver 24 are shown.
Represents a positive analog voltage with respect to the reference electrode 30,
The voltage is applied to each of the connected column electrodes 18. Column electrode 1
Applying a positive voltage to 8 causes a voltage at free surface 88 (FIG. 2) of dielectric material layer 46 to be substantially equal to the applied voltage. Therefore, there is no change in the potential difference applied to the capacitor model 80, and in FIG.
2 and the bottom plate 86 are depicted with a white surface.

In this case, the gas in the groove 20 is not ionized, and the voltage generated on the plates 82 and 86 of the capacitor model 80 is equal to the potential of the reference electrode 30 in the groove. Positive for me. When the data strobe circuit 28 generates a negative voltage pulse on the row electrode 62 in the groove 20, the gas in the groove 20 becomes ionized. The groove 20, whose row electrode is receiving the strobe pulse,
In FIG. 6, it is indicated by a thick line. Under these conditions, the grounded reference electrode 30 and the strobed row electrode 62 function as an anode and a cathode, respectively, for the plasma in the groove.

Electrons in the plasma neutralize the positive charge induced on plate 86 at the bottom of capacitor model 80.
Strobed row capacitors. Model 80 is
It is charged by the data voltage applied to it. This state is shown in FIG. 6 in which the plate 82 at the bottom has a white surface and the plate 86 at the bottom has a line. When the storing (accumulation) of the data voltage applied to the capacitor model 80 is completed, the data strobe circuit 28
The second negative voltage pulse ends. This terminates the strobe pulse and also extinguishes the plasma.

Each of the row electrodes 62 is strobed in a similar manner until the entire addressing of the display surface 14 is completed and the image field of data is stored. The voltage remains stored in each of the strobed row capacitor models 80 for at least the duration of the image field. And, it is not affected by subsequent changes in the data voltage applied to the top plate 82 of the capacitor model 80. The voltage stored in each of the capacitor models 80 varies according to the analog data voltage representing the display data of a subsequent image field.

In the display device 10, when the image field is of the non-interlaced type, the analog data voltage applied to the column electrode 18 in the next image field has the opposite polarity. In the long run, the DC voltage component is net zero by reciprocating between positive and negative polarities when transitioning from one image field to the next image. This is particularly required for long-term use of liquid crystal materials. The liquid crystal material produces a gray scale effect depending on the effective value of the applied analog data voltage. For this reason,
The image created is not affected by the polarity alternation of the analog data voltage. In the display device 10, when the image field is of the interlace type, the analog data voltage applied to the column electrodes 18 of successive image frames has a polarity such that the DC voltage component becomes net zero in the long term. Be the opposite. Each image frame consists of two image fields, each image field consisting of half the number of addressable lines.

As is evident from the above description, the ionizable gas filling each groove 20 changes the contact position between the two switching states depending on the voltage applied by the data strobe circuit 28. Function as an electrical switch 90 that changes. In FIG. 6, switch 90 in the open position is connected to reference electrode 30 and is driven by a strobe pulse applied to row electrode 62. Without the strobe pulse, the gas in groove 20 would be non-ionized and thus non-conductive. When the switch 90 shown in FIG. 6 is closed, the switch 90 is connected to the reference electrode 30, is applied to the row electrode 62, and is driven by a strobe pulse strong enough to ionize the gas in the groove 20. As a result, the state becomes conductive. In FIG. 6, the data strobe circuit 28
Of the three output amplifiers strobes a row of capacitor models 80, which applies and stores the display data voltage.

To function as a switch, the ionizable gas contained in the groove 20 below the glass electrode assembly 40 cooperates with the dielectric material layer 46 to remove the reference electrode from the dielectric material layer 46. A conductive path is provided to 30. The plasma in the groove 20 with the row electrode 62 subjected to the strobe pulse provides a ground path to a capacitor model 80 that represents a portion of the liquid crystal material located adjacent to the plasma. As a result, the analog data voltage applied to the column electrode 18 is transferred to the capacitor model 8
0 can be sampled. When the plasma disappears, the conductive path disappears. Therefore, the sampled data is held in the display element. The voltage remains stored in the electro-optic material layer 44 until a voltage is generated in the electro-optic material layer 44 representing a new line of data in a subsequent image field. The above-described addressing apparatus and techniques provide a substantially 100% duty cycle signal for each of the display elements 16.

FIG. 7 is a time chart for determining the limit of the number of data lines that can be addressed by the display device 10 during the image field period. In FIG. 7, after row electrode 62 of strobed groove 20 receives a strobe pulse, a representative data line n requires time 92 to generate a plasma. This plasma generation time 92 is not substantially a factor in limiting the number of addressable lines in the image field by initiating a strobe pulse prior to the previous line n-1. In the preferred embodiment, the plasma generation time in helium (He) gas is nominally 1.0 microsecond.

The data setup time 96 represents the time during which the data driver 24 changes state between data values on two adjacent data lines, causing the output amplifier 22 to generate an analog voltage signal, Applied to the column electrode 18. The data setup time 96 is
It is a function of the electronic circuit used to configure the driver 24. Setup times of less than 1.0 microsecond are achievable.

The data acquisition time 98 depends on the conductivity of the ionizable gas in the groove 20. FIG. 8 depicts the data capture time 98 as a function of the plasma current flowing between the reference electrode 30 and the row electrode 62 in the groove 20. The curve in FIG. 8 represents the time required for the display element to acquire 90% of the voltage corresponding to the data. FIG.
Shows that the ions generated by the helium gas plasma have a shorter data acquisition time compared to neon (Ne). The plasma electron flow flows from the cathode (row electrode 62) to the anode (reference electrode 30).

The preferred operating point is to achieve the shortest data acquisition time for positive ion current. In the particular case shown in FIG. 8, at such an operating point, the helium
Using a gas at a pressure of 40 mbar and a current of 7.5 milliamps, a data acquisition time of about 0.5 millisecond is achieved. Helium can achieve shorter data acquisition times than neon because helium is a lighter ion and more mobile. The optimum values of the pressure and the voltage depend on the size and shape of the groove 20.

The plasma extinction time 94 represents the time required for the plasma in the groove 20 to return to a non-ionized state after the removal of the strobe pulse from the row electrode 62. FIG. 9 shows the plasma extinction time with no more than 3% interference as a function of the anode / cathode current in the display panel 12. FIG. 9 shows that the plasma extinction time 94 increases as a function of the current flowing in the plasma from the row electrode 62 to the reference electrode 30. Row electrode 62
The amount of current flowing through the plasma is determined by the intensity of the strobe pulse applied to the. FIG. 9 shows that the reduction of the plasma extinction time 94 is achieved by applying a continuous bias voltage of about +10 OV. FIG. 9 further shows that when a bias voltage of +10 OV is applied, the plasma disappearance time 94 is reduced to about one tenth as compared with the case where the bias voltage is zero.

The time required to address a data line is equal to the sum of the data setup time 96, data acquisition time 98, and plasma extinction time 94. The number of lines that can be addressed during an image field is equal to the image field time divided by the time required to address a data line. For a non-interlaced 60 Hz frame rate,
The number of data lines of the display device 10 can exceed 9000 with the simple addressing technique described above. Note that the number of addressable data lines is not the same as the resolution of display device 10. The resolution is
It is a function of the width of the groove 20 and the width of the column electrode 18.

The use of priming techniques has the advantage of ensuring the ability to address a relatively large number of lines in an image frame. Priming involves introducing ions to initiate a gas discharge. Priming of the display device 10 is achieved by passing a current through a priming groove (not shown). This priming groove is the groove 20
And each of the grooves terminates at the edge of the display panel 12. By priming
If that were not the case, the plasma could be generated without an initial statistical delay that would make the plasma generation time unpredictable.

FIGS. 1OA and 1OB show an alternative circuit of the data driver 24, and the corresponding components between them are indicated by subscripts a and b, respectively. FIG. 10
At A, the data driver 24a samples the data signal and stores it in the buffer memory 100. The data signal is in analog or digital form. The buffer memory 100 includes a charge-coupled device (CC
D) or a sample-and-hold type, which stores analog data signals. Buffer memory 100
May be in digital form for storing digital data signals. Element 22 may be a buffer amplifier or a digital-to-analog converter, depending on whether buffer memory 100 holds analog voltages or digital data. Element 22 allows for parallel transmission of the analog voltage to the column electrodes. The data driver 24a can operate at high speed. Because CC
This is because D and the sample-and-hold circuit can capture data at high speed, and the analog voltage is simultaneously transmitted to the column electrode 18a in parallel.

In FIG. 1OB, the data driver 24
b samples the analog data signal serially by closing and opening each one of the switches 104 sequentially. Switch 104 is connected to capacitor 106. The capacitor 106 is
When the switch is closed, it stores charge from the data signal. As a result, an analog voltage sample of the data signal is supplied from one end to the other end of one column electrode 18b. The sampling clock signal applied to the control electrode of switch 104 sets the sampling rate. The data setup of the circuit in FIG.
Time 96 is the data setup time 9 of the circuit in FIG. 10A by a multiplier equal to the number of column electrodes 18b.
Greater than 6.

For proper operation within display device 10, it is necessary for data driver 24b that the horizontal blanking time from row to row exceeds the sum of data capture time 98 and plasma extinction time 94. It is.

FIGS. 11A and 11B illustrate the number of data strobe outputs required for a typical display panel 12 in which each reference electrode 30 has a fixed reference voltage and nine grooves for receiving strobe signal pulses. Comparing. The display panel of FIG. 11A has a grounded reference electrode 30 and 9
It has two different strobe output amplifiers 26 and a data strobe circuit 28 driving different row electrodes 62. The display panel shown in FIG. 11B has three sets of reference electrodes 30 and another three sets of row electrodes 62. The groove 20 (FIG. 4) having a reference electrode forming any one of the set of reference electrodes includes any one electrode 62 of the row electrode set. The display device 10 displays one of the sets of the reference electrodes 30 for a predetermined time interval.
Strobe only one. During the strobe time interval,
The display 10 addresses the display elements 16 by driving the column electrodes 18 and strobes a set of row electrodes 62 contained within the groove 20 having the reference electrode 30 that receives the strobe pulse. The row electrode 62 of the groove 20 whose reference electrode 30 has not received a strobe pulse is thus not activated.

That is, in FIG. 11B, a plurality of adjacent groove-shaped concave portions (N is an integer of 2 or more) are set as one set, and the second electrodes (row electrodes 62) of the corresponding groove-shaped concave portions of different sets are connected to each other. Are commonly connected, and the third electrodes (reference electrodes 30) in the N groove-shaped concave portions are commonly connected to each other in each set. The signal applying means sequentially applies the first strobe signal to each set of commonly connected third electrodes, and simultaneously applies the first strobe signal to the third electrodes in the groove-shaped recesses of each set. During this period, the second strobe signal is sequentially applied to each second electrode in each set of groove-shaped concave portions. Therefore, the number of output amplifiers 26 of the data strobe circuit 28 of the address device can be reduced by electrically connecting the output amplifier 26 of the data strobe circuit 28 to the reference electrode 30 and the row electrode 62 in the groove 20. . In the exemplary display panel 12 of FIG. 11B, the number of data strobe output amplifiers 26 is reduced from nine to six.

FIG. 12 shows the display panel 12 of FIG. 11B with respect to the number of addressable data lines that can be mounted in an addressing device of the type implemented.
5 is a graph showing a required minimum number of drivers. FIG.
2 shows that a substantial reduction in drivers is achieved in a display having a relatively large number of data lines.

The address device of the present invention is a self-scan (Self-Scan: Developed by Burroughs).
The use of other technologies similar to those implemented in the trademark) display can help reduce the number of drivers. A display device using such a technique employs display cells that can be viewed by an observer and scan cells that cannot be viewed by an observer. The scan cell controls the state of the display element by sending activated priming particles to a cell of ionizable gas. In the grooves of the scan cells, the plasma discharge sequentially moves to the next display cell and generates priming particles that activate the adjacent display cell.

The display panel 12 could provide an ion source that moves sequentially from one groove to the next by electrical splitting of the priming grooves that are orthogonal. With respect to the techniques described above, wall charge coupling or other known techniques could be employed to further reduce the number of drivers.

The addressing technique of applying data voltages of positive and negative polarities in the alternating image field is easy to use in the embodiment of the display device 10 employing the driver reduction technique described with reference to FIGS. 11B and 12. . The addressing speed can be further increased by an alternative addressing technique in which only a positive polarity data voltage is applied. Such alternative technologies are:
An erasure field is introduced at the end of each image field.

In this type of addressing technique, while scanning the erase field, the data strobe circuit 28 applies a relatively short period of positive and negative pulses to the row electrodes 62 of the groove 20 in a continuous manner. The driver 24 applies a substantially ground potential voltage to the column electrode 18. During the application of the positive pulse, reference electrode 30 and row electrode 62 act as the cathode and anode of the plasma, respectively. Since the previously required data voltage is positive, the charge stored on the storage element 16 causes a negative charge on the surface 88 of the dielectric material layer 46. Therefore, it functions as a cathode. The cathode is surrounded by a relatively high concentration of ions, which rapidly neutralizes the negative charge on the dielectric material layer 46. As the potential of the dielectric material layer 46 approaches that of the anode, residual positive charges can accumulate and reach significant levels. During the application of the negative pulse, the ground potential applied to the column electrode 18 forces residual positive charge to ground in a manner similar to that applied during writing of the image field.

If no positive pulse is used, the speed at the address is limited by the positive ion charging phenomenon described above. However, this alternative addressing technique is not compatible with the driver reduction technique described in connection with FIGS. 11B and 12.

In another addressing technique of this type, the data strobe circuit 28 has two or more (eg, 10
), A negative pulse is applied to the row electrodes 62 to simultaneously erase data in one row. In this technique, a small duty cycle non-uniformity occurs across the display surface 14 of the display panel 12.

The flat panel display 10 may be modified to form a versatile analog data memory device 110, including an array of memory elements.
This embodies the address device and is a second embodiment of the present invention. Such a modification removes the polarizing filters 34 and 36 and allows the liquid crystal material layer 44 of FIGS. 2, 4 and 5 to be removed.
May be removed if present.

FIG. 13 shows an equivalent circuit of the memory device 110. Except as noted above, the devices shown in FIGS. 6 and 13 are similar. Therefore, corresponding components in FIGS. 6 and 13 have the same reference numerals. In the memory device 110, the dielectric 46 functions as a dielectric element of the capacitor model 80, which represents a memory element. The column electrode 18 does not need to be made of an optically transparent material, but may be made of aluminum or another conductive material. The data drive output amplifier 22 of the memory device 110 functions as a column electrode drive amplifier in a data write mode, and functions as a column electrode detection amplifier in a data read mode. The drive output amplifier 22 and the data drive circuit 24 serve as signal application / readout means. Data of the device of FIGS. 6 and 13
The strobe output amplifier is similar.

In FIG. 13, each output amplifier 22 of the data drive circuit 24 includes a high-speed operational amplifier 112. The parallel circuit of the feedback capacitor 118 and the switch element 120 is connected to the inverting input terminal 114 and the output terminal 11 of the amplifier 112.
6 is connected. The amplifier 112 is selectively connected to the switch element 12 in the data write mode.
By driving 0 and making it conductive, it constitutes a voltage follower, and in the data read mode, by driving the switch element 120 and making it non-conductive, it constitutes an integrator. The non-inverting input terminal 122 of the operational amplifier 122 is connected to the movable contact 124 of the switch element 126.
Connected to. This switch element selectively connects the non-inverting input terminal 122 to the reference voltage Vr or the output signal conductor of the data drive circuit 24.

Whenever in the write mode, the output amplifier 22 supplies a data drive signal to the column electrodes 18 forming the memory elements of the memory device 110. This means
The operational amplifier 112 is configured as a voltage follower, and the movable contact 124 of the switch element 126 for supplying the data drive signal is arranged from the data drive circuit 24 to the non-inverting input terminal 122 of the operational amplifier 112. Therefore, when the amplifier 112 is in a voltage follower in the write mode, the voltage of the non-inverting input terminal and the voltage of the inverting input terminal become equal, so that the non-inverting input terminal functions as a data drive signal input terminal, and Functions as an output terminal for the data drive signal. During this period, the row strobe pulse applied to the row electrode 62 in the groove 20 constituting the memory element 110 excites the ionizable gas in the groove to bring it into an ionized state. This allows the capacitor model 80 to be used in the manner described in connection with FIG.
To generate a data voltage. The magnitude of the voltage applied to the capacitor model 80 represents a data drive signal.

In the data read mode, data amplifier 22 detects a current in column electrode 18 constituting a memory element of memory device 110. This is achieved through a two-step procedure.

First, the movable contact 12 of the switch element 126
Reference numeral 4 is arranged to input the reference voltage Vr to the non-inverting input terminal 122 of the operational amplifier 112. this period,
The row strobe pulse is inactive to maintain the ionizable gas in a non-ionized state. Therefore, the reference voltage Vr is applied to the output terminal 116 of the operational amplifier 112, the column electrode 18, and the capacitor model 80.
And the top plate 82 of Feedback capacitor 118
Is neutralized to 0.0 volts for this purpose. However, the memory device 110 can be configured to operate with an offset voltage between the input and output of each operational amplifier 112.

Second, after the voltage applied to the feedback capacitor 118 becomes 0.0 volt, the operational amplifier 112
Are configured as semi-integrators whose input 114 receives a current from the column electrode 18. The potential difference between the bottom plate 86 of the capacitor model 80 and the reference electrode 30 is a function of Vr and the previously described data voltage across the capacitor model 80. When the row strobe pulse again ionizes the ionizable gas,
The bottom plate 86 of the capacitor model 80 is
0 is electrically connected. Therefore, capacitor model 8
The voltage applied to 0 changes. The operational amplifier 112 configured as an integrator detects this voltage change and supplies a voltage proportional to the above-mentioned data voltage applied to the capacitor model 80 to the output terminal 116.

There are other ways to generate a data voltage on the capacitor model 80 to facilitate its function as a memory element. For example, by using an optically transparent column electrode 18 and replacing the dielectric material layer 46 with a photoconductive material and exposing the memory device 110 to visible light, the memory device 110
The voltage applied to the capacitor model 80 is modulated in proportion to the intensity of light incident on the capacitor model 80. The change in voltage across the capacitor model 80, which is proportional to the intensity of the incident light, is recovered in the data read mode, as described above. Photoconductive material layer 46 and optically transparent column electrode 1
8 is an image detecting device corresponding to the characteristics of the analog data memory.

In the image sensing device described above, providing a plurality of layers of photoconductive material 46 as electrically insulated bands would avoid conduction between adjacent capacitor models 80. Providing a metal strip or other conductive material along the edge of the optically transparent electrode reduces data correction time in the data read mode by reducing the time required to read the data voltage across the capacitor model 80. Efficiency is improved.

The above-described image detecting device utilizes the photoconductive property of the layer 46 of the photoconductive material during the data reading mode. It is also possible to directly utilize the photoconductivity of the layer 46 of photoconductive material. In this case, the data element 16 will be more preferably characterized as a sensing element, and the capacitor model 80 will also be more preferably a current modulating element. This means that between the strobe electrode 62 and the reference electrode 30, the row strobe
This can be achieved by applying a voltage to the column electrode 18 that causes a voltage gradient to occur in the layer 46 while the pulse is being applied. The current flowing from the reference electrode 30 through the layer 46 and the column electrode 18 to the output 116 of the operational amplifier 112 is
Output signal. When the feedback capacitor 118 is replaced by a resistor, the voltage appearing at the output 116 of the operational amplifier 112 is proportional to the current flowing through the layer 46.

Although the preferred embodiment of the present invention has been described above, it is easy for those skilled in the art to make various modifications without departing from the gist of the present invention.

[0073]

According to the present invention, it is possible to provide an inexpensive and high-yield addressing device using an ionized gas for a display device and a memory device. In each of the groove-shaped recesses of the second substrate, a second electrode and a third electrode substantially parallel to the longitudinal direction of the groove-shaped recess are formed.
A strobe signal (second signal) is selectively supplied between the electrode and the third electrode. This allows for relatively low voltage,
An electric field having a uniform gradient is formed in a direction crossing the groove-shaped concave portion, and uniform gas ionization occurs, and a uniform and good switching operation by the ionizable gas is obtained in each cell. After ionizing the gas, a data signal (first signal) for display or accumulation is supplied between the first electrode and the third electrode used for the strobe signal. Therefore, since the third electrode is also used to supply both the data signal and the strobe signal, the structure of the address device can be simplified. Further, a plurality of adjacent groove-shaped recesses (N is an integer of 2 or more) are set as one set, and the second electrodes of the corresponding groove-shaped recesses of different sets are commonly connected to each other. By commonly connecting the third electrodes in the groove-shaped recess,
The number of output amplifiers of the signal applying means for supplying the strobe signal can be reduced.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram illustrating the concept of the present invention.

FIG. 2 is a partially sectional perspective view of a display panel using the present invention.

1. FIG. 3 is a plan view showing the display panel shown in FIG.

FIG. 4 is a sectional view taken along lines 4-4 in FIG. 3;

FIG. 5 is a sectional view taken along line 5-5 in FIG. 3;

FIG. 6 is a circuit diagram showing an equivalent circuit of FIG. 2;

FIG. 7 is a diagram showing a timing chart for determining the maximum number of addressable data lines used in the present invention.

FIG. 8 is a graph comparing the relationship between the neon gas and helium gas data capture times as a function of the current flowing between the electrodes provided in the grooves of the display panel shown in FIGS.

FIG. 9 is a diagram showing a relationship between current flowing through a cathode and an anode in helium gas and plasma extinction time.

FIG. 10 is a diagram showing an alternative circuit of the data driver shown in FIG. 1;

FIG. 11 is a diagram showing an alternative circuit of the data strobe shown in FIG. 1;

FIG. 12 is a diagram showing a relationship between the number of drivers and the number of addressable data lines in FIG. 11;

FIG. 13 is a diagram showing an equivalent circuit of the memory device of the present invention.

[Explanation of symbols]

 Reference Signs List 18 first electrode 20 groove-shaped concave portion 22, 24 first signal applying means 26, 28 second signal applying means 30 third electrode 44 electro-optic material layer (dielectric layer) 46 dielectric material layer (dielectric layer) 48 1 substrate 54 2nd substrate 62 2nd electrode

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁶ Identification code FI G09G 3/36 G09G 3/36 // H04N 5/66 102 H04N 5/66 102B (72) Inventor Paul Sea Martin United States Oregon State 97225 Portland Southwest Sirlow Drive 9950 (72) Inventor Hitch Wayne Olmsted United States 97006 Beaverton Northwest Marco La Court 16995 (72) Inventor John Jay Horn United States 97123 Hillsboro, Oregon Southwest Tohand Dread and Thirty-Eight Avenue 765 (56) Reference JP-A-1-217396 (JP, A) JP-A-49-84780 (JP, A) JP-A-9-134151 JP, A) United States Patent 2847615 (US, A)

Claims (2)

(57) [Claims] A first substrate having a plurality of first electrodes formed substantially parallel to each other on one main surface, and intersecting the first electrode on a main surface of the first substrate facing the main surface. A second substrate having a plurality of groove-shaped recesses formed substantially parallel to each other and filled with an ionizable gas; and inside the plurality of groove-shaped recesses on the main surface of the second substrate. the second and the third electrodes, provided we dielectric between the first substrate and the second substrate that is substantially parallel to the longitudinal direction of the groove-shaped recess
A dielectric layer provided between the dielectric layer and the second substrate;
Shielding the body layer from the ionizable gas in the groove-shaped recess.
A dielectric material layer, first signal applying means for selectively applying a first signal between the first electrode and the third electrode, and a second signal applying means selectively between the second electrode and the third electrode. Second signal applying means for applying a signal, selectively supplying the second signal between the second electrode and the third electrode, and receiving the second signal and the second electrode. Ionizing the gas in the groove-shaped recess having three electrodes, the groove-shaped recess containing the ionized gas and the first gas;
An address device for addressing a portion of the dielectric layer corresponding to an intersection with the first electrode to which a signal is selectively supplied. 2. The method according to claim 1, wherein the plurality of groove-shaped concave portions are adjacent to each other.
Is an integer of 2 or more) as one set, and the second electrodes of the corresponding groove-shaped recesses of different sets are commonly connected to each other, and the third electrodes in the N groove-shaped recesses are connected to each other for each set. Common connection,
The second signal applying means sequentially applies a first strobe signal to each pair of the commonly connected third electrodes,
A second strobe signal is sequentially applied to each of the second electrodes in each of the sets of grooved recesses while the first strobe signal is commonly applied to the third electrodes in each of the sets of grooved recesses. 2. The addressing device according to claim 1, wherein the address is applied.