WO2006035532A1

WO2006035532A1 - Display and its image displaying method

Info

Publication number: WO2006035532A1
Application number: PCT/JP2005/010983
Authority: WO
Inventors: Hisanobu Matsuzoe
Original assignee: Fukuoka Technoken Kogyo, Co., Ltd.
Priority date: 2004-09-27
Filing date: 2005-06-15
Publication date: 2006-04-06
Also published as: JPWO2006035532A1; JP3993884B2

Abstract

A display which provides both large screen and high definition, exhibiting excellent practicality and visibility, and further, exhibiting excellent energy saving performance by eliminating the need for conduction at the time of displaying a still image. The display comprises (a) a print section mounted with a thermal discharge print head, which has a discharge section having a discharge electrode and a heating means having a heat generating section for heating the discharge electrode, and controls discharge generation by controlling the temperature of each discharge electrode whereupon a discharge control voltage is applied, and (b) a display medium from which a visible image emerges through discharge from the thermal discharge print head.

Description

Specification

Display device and image display method thereof

Technical field

TECHNICAL FIELD [0001] The present invention relates to a display device for writing and displaying an image with a heat-discharge type print head on a display medium on which a visible image appears by the action of electric discharge and which can be repeatedly recorded, and an image display method thereof.

Background art

[0002] In recent years, along with the practical application of high-intensity blue light-emitting diodes, display devices using light-emitting diodes (LEDs) of three primary colors (R, G, B) are commonly used for advertising displays installed outdoors. It is reaching. However, a display device using a light-emitting diode can easily be enlarged, but is not suitable for high-definition because the pixels are coarse. On the other hand, a display device using liquid crystal (LCD) with extremely fine pixels can be made high-definition, but it is difficult to make a large screen, so it is not suitable for advertising displays installed outdoors.

As described above, a display medium used for a screen of a conventional display device is suitable for a large screen, but is not suitable for a high-definition, and conversely, a display medium suitable for a high-definition is suitable for a large screen. For this reason, there was a problem that there was a trade-off between large screen and high-definition.

Further, in a conventional display device, it is necessary to energize to display an image on a screen, whether it is a moving image or a still image. For this reason, even if it is only necessary to sequentially display the power of the still image as necessary, if the same power is consumed as in the case of displaying the moving image, there is a problem in terms of V and power saving.

[0003] On the other hand, the present applicant filed (Patent Document 1), “The ion generator selectively irradiates a rewritable recording medium by an electric field, and statically irradiates the surface of the recording medium. An image forming apparatus that forms an electrostatic latent image and selectively displays the image is disclosed.

An application of an electrostatic latent image forming method using an ion irradiation method, which is one form of such a heating and discharging method, is a static image in which a visible image appears inside due to the action of the electric charge of the electrostatic latent image formed on the surface. Direct formation of electrostatic latent image by ion irradiation on electro-development type recording media Therefore, in order to write in a non-contact manner on an electrostatic development type recording medium of a recording medium generally called a digital paper, it is an optimal image forming apparatus that can be considered at present.

In FIG. 4 of (Patent Document 1), the ion generator for performing ion irradiation is fixed, and the recording medium can be used as printing paper by transporting the recording medium. Therefore, this is an image forming apparatus (printer). is there. However, if rewriting is performed repeatedly with an ion generator without replacing the recording medium (not used as printing paper), this is a kind of display device. As described above, a display device using a recording medium as a display medium for a screen can display a still image while sequentially rewriting it as necessary. Therefore, if it is downsized, it is called an electronic book. It can also be used as a device that can be used as an advertising display installed outdoors.

Incidentally, as a digital paper at the present time, a minute ball is color-coded into two colors (for example, black and white), and the ball is rotated to display an arbitrary color depending on the electrical characteristics of each color. Electrostatic system, liquid crystal plate or liquid crystal block liquid crystal shutter that displays two colors (for example, black and white) of fine powder mixed in the ball, and displays only one color floating due to the difference in electrical characteristics of the fine powder of each color There is a liquid crystal system that displays the background color of the part where the shutter is opened by opening and closing.

Patent Document 1: Japanese Patent Laid-Open No. 2003-326756

Disclosure of the invention

Problems to be solved by the invention

[0004] However, Patent Document 1 discloses an image forming apparatus compatible with a digital paper equipped with an ion generator, and an image forming apparatus compatible with plain paper of an electrostatic latent image forming method that does not require an optical system. However, no specific configuration for use as a display device, an image forming method, a display method, or the like has been disclosed. In particular, there has been a demand for specific examination of a configuration for color display, a display screen switching method, and the like.

[0005] The present invention solves the above-described conventional problems, and it is possible to achieve both a large display screen and a high-definition display screen, which is excellent in practicality and visibility, and in displaying a still image. Necessary for providing a display device that does not require energization and has excellent energy savings, and for switching display screens. It is an object to provide an image display method for a display device with excellent functionality that can reduce the time required for image display.

Means for solving the problem

In order to solve the above problems, a display device and an image display method thereof according to the present invention have the following configurations.

The display device according to claim 1 of the present invention includes: (a) a discharge part having a discharge electrode; and a heating unit having a heat generating part for heating the discharge electrode, to which a discharge control voltage is applied. And a printing unit equipped with a heating and discharging type print head that controls the generation of discharge by controlling the temperature of each of the discharge electrodes, and (b) a visible image appears due to the discharge from the heating and discharging type print head. And a display medium.

This configuration has the following effects.

(1) Since a printing unit equipped with a heat discharge type print head is provided, an image can be formed and displayed on a display medium such as a digital paper on which a visible image appears by discharge.

(2) The image written on the display medium with the heat-discharge type print head can be held without any power consumption as well as printed on the printing paper, and is excellent in energy saving.

(3) In a heat-discharge type print head, a discharge control voltage (which means a voltage range in which discharge does not occur when applied only because of low voltage, but discharge occurs when heated) is applied to heating means. By controlling the heating in this way, thermoelectrons are emitted from the heated discharge electrode and discharge and light emission occur, and the ion generation amount can be controlled in an atmosphere where ions can be generated. Can be recorded on display media such as digital paper.

(4) Since the amount of ions generated and the intensity of light emission associated with the discharge from the heat-discharge type print head can be controlled by heating control, the area gradation on the display medium becomes easy and the image quality can be improved. Monkey.

[0007] Here, in the discharge part of the heat discharge type print head, one end of a plurality of discharge electrodes divided in a comb shape is connected by a common electrode, or both ends of a plurality of discharge electrodes are connected by a common electrode. It can be formed like a ladder. By providing a common electrode in the vicinity of the discharge electrode, it is possible to reduce the cooling effect of the discharge electrode and stop heating by increasing the heat dissipation area of the discharge electrode and increasing the heat capacity. Responsiveness is improved, and a stable voltage can always be applied by reducing the resistance value, so that the stability of discharge can be further improved.

In particular, when the width of the common electrode is wider than the width of the discharge electrode, the cooling effect of the discharge electrode, which is temporarily heated to 200 to 300 ° C., can be improved and heat can be prevented. Discharge can be stopped in response to heat off quickly, and the discharge time interval can be shortened to enable or disable discharge. In addition, the resistance value of the common electrode can be reduced, and the potential difference generated between the discharge electrodes connected by the common electrode can be suppressed as much as possible. Therefore, variation in the discharge amount in each discharge electrode can be reduced, Excellent discharge stability.

Further, a conductive material layer may be formed on at least the surface of the common electrode in the discharge part. As a result, the resistance value of the common electrode can be further reduced, the potential difference generated between the discharge electrodes can be reliably reduced, and the discharge stability is excellent. As long as the conductive material layer has conductivity superior to that of the discharge part, it can be easily formed by screen printing of silver paste or silver plating. By increasing the thickness of the conductive material layer, the resistance value of the common electrode can be reduced, and the discharge stability can be improved.

When the discharge electrode is formed in a comb shape, the discharge electrode can be formed in a substantially rectangular shape, a trapezoidal shape, a bullet shape, a semicircular shape, or a combination thereof. Further, the peripheral length around the edge of the discharge electrode can be increased by dividing a part of the discharge electrode with a slit or the like, or by forming an uneven portion on the peripheral edge. Since the discharge electrode has a large amount of discharge from the periphery of the edge, it is possible to increase the amount of discharge from the discharge electrode by increasing the peripheral length of the periphery of the edge, increasing the amount of irradiated ions and light emission intensity. The discharge control device is excellent in energy saving and efficiency. In addition, since the voltage applied to the discharge electrode can be set small,

Also, the long life of the discharge electrode is excellent.

Instead of dividing the end portion of the discharge electrode or forming the concavo-convex portion on the peripheral edge portion, the discharge hole portion may be formed corresponding to the heating position of the heating element. As a result, a discharge can be generated from the periphery of the edge of the discharge hole, and the same effect as that obtained by dividing the end of the discharge electrode can be obtained. The shape of the discharge hole can be formed in various shapes such as a substantially circular shape, a substantially elliptical shape, a polygon such as a quadrangle and a hexagon, and a star shape. In addition, the discharge hole per heating location These numbers and sizes can be appropriately selected and combined.

[0009] As the discharge electrode, an electrode in which a metal such as gold, silver, copper, or aluminum is formed by vapor deposition, sputtering, printing, etc., and then etched to form a pattern is suitably used. In addition, a conductive material such as carbon may be used.

Since the discharge control voltage can be applied to the discharge electrode and the generation of the discharge can be controlled by heating, it is possible to easily generate the discharge selectively from any discharge electrode by selecting the heating location by the heating means. be able to.

When the discharge electrode is made of aluminum, the thickness is preferably 0.1 μπι to 100 / ζ m. As the thickness of the discharge electrode becomes thinner than 0.1 μm, it tends to be affected by wear, and the life of the discharge electrode tends to be shortened, and as it becomes thicker than 100 μm, the heat capacity increases and the heating is turned on and off. There is a tendency that the responsiveness tends to decrease, both of which are not preferable.

[0010] The discharge electrodes of the discharge part may be arranged in a plurality of rows with a plurality of discharge electrodes formed at the same basic pitch as a single row. By arranging in a staggered manner so as to interpolate between the basic pitches, the minimum pitch between the discharge electrodes can be made narrower than the basic pitch, and the overall resolution can be improved. Since the basic pitch between the discharge electrodes in each row can be formed widely, processing is easy, the mass production is excellent, and the yield can be improved.

When a common electrode for connecting a plurality of discharge electrodes is provided, the common electrode may be independent for each column arranged in parallel! /, Or may be common for multiple columns! /.

In addition, when the entire array of discharge electrodes formed at the basic pitch is inclined, the pitch in the arrangement direction of the discharge electrodes projected on the horizontal plane (the pitch during image formation) must be narrower than the basic pitch. It is possible to improve the resolution by mounting at high density without any processing restrictions.

[0011] When the induction electrode is formed so as to be separated from the discharge electrode and insulated from the discharge electrode, the gap between the discharge electrode and the induction electrode is always kept constant, so that there is a voltage between the discharge electrode and the induction electrode. By applying, discharge can be generated efficiently. In addition, by covering the induction electrode with the induction electrode insulating film, the induction electrode can be reliably insulated and the occurrence of a short circuit can be prevented. The material of the induction electrode insulation film is glass, ceramic My strength, synthetic resin, and the like can be preferably used, and can be formed by screen printing, vapor deposition, sputtering, or the like.

In addition, on the back side of the display medium on which recording is performed by irradiation of ions accompanying discharge from the heat discharge type print head, a ground electrode portion for applying an electric field between the discharge electrode of the heat discharge type print head and the display medium or It is preferable to provide a positive voltage application unit that applies a positive voltage.

. By providing the ground electrode portion, the discharge electrode force of the heat discharge type print head can be irradiated with ions toward the display medium regardless of the presence or absence of the induction electrode. In addition, when irradiating negative ions, by providing a positive voltage application section, a positive voltage can be applied to the display medium side, and the same effect can be obtained. Thereby, unit dots in the printing unit of the display device can be miniaturized, the irradiation position accuracy can be improved, and high-definition recording can be performed.

If no induction electrode is provided, the process of forming the induction electrode can be omitted, resulting in excellent productivity, and the discharge control device can be miniaturized and mounted at a high density. The resolution can be increased.

Of the discharge part, the vicinity of the heating position by the heat generating part of the heating means becomes the discharge generation part, but it is preferable to cover the discharge part except for the discharge generation part. When the discharge part has a common electrode and a discharge electrode, the coating film is covered on the common electrode and on the discharge electrode except for the discharge generation part. By forming the coating film excluding the discharge generation part of the discharge electrode, a step can be formed between the surface of the discharge generation part and the surface of the coating film. For this reason, the gap between the discharge electrode and the display medium or the like disposed opposite to the discharge electrode can be kept constant, so that the discharge having the discharge electrode force can be stabilized. It is possible to prevent the display medium from coming into contact with the discharge generation part of the discharge electrode.

More specifically, the coating film has an opening formed in a substantially circular shape, a substantially elliptical shape, a substantially rectangular shape, or the like in the discharge generating portion of the discharge portion (near the heating position by the heat generating portion of the heating means). The opening may be formed independently for each of the plurality of discharge generation portions, or may be formed in a continuous long hole shape so as to extend over the plurality of discharge generation portions.

The coating film is made of an insulator and is made of glass, synthetic resin such as aramid polyimide, SiO

A material such as 2nd ceramic or My strength is preferably used. The coating film can be screen printing, vapor deposition, It can be formed by a knotter or the like.

In addition, when an uneven | corrugated | grooved part is formed in the surface of a coating film, the surface distance of a coating film can be extended and surface resistance can be increased. For this reason, it is possible to prevent electric leakage from the discharge generation part of the discharge electrode to the surroundings, so that the adverse effect on the driver IC of the heating means does not occur and the stability of discharge control can be improved. In addition, since there is no electric leakage, the stability and efficiency of the discharge are excellent because the applied voltage applied to the discharge electrode does not decrease.

[0013] According to the heat-discharge type print head, it is possible to form an electrostatic latent image or an image by an oxidation-reduction reaction. Further, according to the light emission of discharge, a digital paper or the like using a photochromic compound that forms an image with ultraviolet rays or visible rays can be used as a display medium.

When the display device has either one of the printing unit moving unit that moves the printing unit or the display medium conveyance unit that conveys the display medium, the display unit moves relative to the display medium by moving the printing unit and the display medium relatively. Images can be written.

As the display medium, an endless loop (closed loop) shape in which both ends of the sheet are connected or a finite length sheet (open loop) shape can be used. When the display medium has a sheet (open loop) shape, the display medium is not limited to a flat shape, and may be arranged in a curved shape. In addition, when the display medium is in an endless loop (closed loop) shape, a cylindrical shape can be arranged in various shapes.

In addition, when a display medium holding unit for detachably holding a display medium is provided as a display device, a user or the like can easily attach and detach the display medium and replace it, which is excellent in maintainability. Even if the display device does not have a display medium from the beginning, it is possible to select an arbitrary display medium capable of forming an image with the heat-discharge type print head and mount it later. And can be widely used as a display device

[0014] The heat generating part of the heating means may be one that can be heated in close contact with the discharge electrode as long as it can selectively heat a plurality of discharge electrodes, or one that is heated away from the discharge electrode. Good.

When the heating means has a heat generating part insulating film that is covered with the heat generating part and is in close contact with the discharge electrode In this case, the heat generating part of the heating means can be formed in close contact with the discharge electrode through the heat generating part insulating film, the heating means and the discharge part can be handled integrally, and the heat discharge type print head is easy to handle, Excellent assembly workability of display device. Further, since the heat generating portion insulating film is covered with the heat generating portion of the heating means, the heat generating portion can be brought into close contact with the discharge electrode, and the power consumption required for image recording can be reduced, resulting in excellent energy saving.

[0015] As the heating means having a heat generating part that is heated in close contact with the discharge electrode, a configuration similar to that of a thermal print head used in a conventional thermal facsimile can be suitably used. Specifically, the heat generation of the heat generating element is controlled by a driver IC electrically connected to the heat generating part having the heat generating element. For example, it is possible to selectively generate heat at an arbitrary portion of one heating element disposed across a plurality of discharge electrodes or a plurality of heating elements individually disposed corresponding to a plurality of discharge electrodes. Some generate heat.

By electrically connecting the heating elements with electrodes formed in a comb-like or matrix pattern, one heating element can correspond to any discharge electrode or to each discharge electrode. It is possible to generate heat by selectively energizing an arbitrary heating element among a plurality of heating elements.

As the heating element, TaSiO, RuO or the like is preferably used.

twenty two

A heat generating part insulating film is formed to protect and insulate the heating element and the electrodes connected to the heating element. As the material of the heat generating part insulating film, SiAl, SiO, SiC, which has high thermal conductivity capable of efficiently transferring heat from the heating element to the discharge electrode is preferred.

2, lead glass, My strength, etc. are preferably used. The heat generating portion insulating film is formed by screen printing, vapor deposition, sputtering, or the like.

[0016] When the heat generating portion insulating film is formed of glass, the film thickness is suitably 2 m to 50 m, preferably 4 μm to 40 m. As the film thickness of the heat generating part insulating film becomes thinner than m, the insulation tends to decrease, and as it becomes thicker than 40 m, it is necessary to increase the applied voltage applied to the discharge electrode and the heat generation amount of the heating element. There is a tendency that energy-saving performance tends to decrease. Also, the resolution tends to decrease as soon as heat is diffused. In particular, as the thickness of the heat-generating part insulating film becomes thinner than 2 m, the surface of the heating element and the electrode connected to the heating element cannot be reliably covered, and pinholes are likely to occur and reliability tends to be lacking. As the thickness exceeds 50 m, the stability of the discharge tends to decrease and mass production There is a tendency to lack in nature, both are not preferred. By setting the film thickness of the heat generating part insulating film to 2 m to 50 m, preferably 4 / z πι to 40 / ζ m, both insulation and thermal conductivity can be harmonized and both are excellent and discharge stability is excellent. . In particular, even if pinholes are generated by each coating, the possibility of pinholes overlapping can be reduced by forming the heat-generating part insulating film by multiple coatings. In addition, the heat generating part can be insulated, so it has excellent reliability.

[0017] When the induction electrode described above is formed on the heat generating portion insulating film by being horizontally separated (offset) from the end portion (edge) on the heat generating portion side of the discharge electrode, the discharge electrode is formed on the heat generating portion insulating film. Instead of forming the induction electrode, an induction electrode insulating film covering the induction electrode may be extended to the heat generating portion insulating film, and the discharge electrode may be formed thereon. In addition, the induction electrode can be formed by being laminated on the discharge electrode via an induction electrode insulating film.

A head board is a hard board made of ceramic or other material with a discharge part or heating means heating part, and a driver IC for controlling heat generation is electrically connected to the heating part of the head board. Is a discharge control device. The heating means includes a driver IC that selectively energizes the heating element to control the heating of the heating element, so that the heating of the heating element can be controlled at a low voltage and applied to the discharge electrode. The voltage itself can be lowered, and the heat discharge type print head can be reduced in size and extended in life. In addition, it is excellent in mass productivity and reliability as a display device.

[0018] The driver IC is wire-bonded to the lead pattern extending from the heat generating portion with a gold wire, and the connecting portion is sealed with an IC protective resin such as epoxy resin. The print head is obtained by disposing a printed wiring board having a connector for electrically connecting to the outside together with a discharge control device on a heat sink formed of a material such as aluminum. The heat generated in the heat generating part can be quickly absorbed by the heat radiating plate and radiated from the heat radiating plate, so that the heat generating part can be rapidly cooled. For this reason, the responsiveness of the discharge stop corresponding to a heating stop can be improved. In addition, the driver IC can be protected from heat and has excellent reliability. When irregularities are formed on the surface of the heat sink by grooves or the like, the surface area of the heat sink can be increased, and the efficiency of heat dissipation can be improved.

An IC cover may be placed on the surface of the driver IC to protect the driver IC. . As a result, the driver IC and the display medium can be reliably prevented from coming into contact with each other, and the reliability is excellent.

[0019] In addition to forming the discharge electrode on the same plane as the substrate on which the driver IC is disposed, the discharge electrode is protruded from the end surface portion of the substrate substantially perpendicular to the surface of the substrate on which the driver IC is disposed, and the surface of the substrate. It can be disposed on a raised portion of a mold or the like, or an edge portion of a substrate that forms an obtuse angle with the surface of the substrate.

When the discharge electrode is arranged in an end face type in which the discharge electrode is placed on the end face of the substrate on which the driver IC is placed, the driver IC and the discharge electrode form a substantially right angle so that the display medium is connected to the driver IC. It is preferable because it can be conveyed linearly without causing interference. Note that the substrate may be formed in a substantially L shape, a substantially rectangular shape, or the like by bending the end surface portion of the substrate to the surface side of the substrate.

If the discharge electrode is of an edge type in which the discharge electrode is arranged on the edge of the substrate on which the driver IC is arranged, the driver IC can be obtained by arranging the discharge electrode on the edge of the substrate that is chamfered in an inclined manner. The discharge electrode forms an obtuse angle, and the same action as the end face type can be obtained without being bulky in the height direction.

When the discharge electrode is placed on the raised surface of the raised part formed on the surface of the substrate on which the driver IC is placed, the discharge electrode is placed on the raised surface of the raised part, near the top of the raised part or on the opposite side of the driver Ic. By disposing the discharge electrode on the raised surface, the same effect as that of the edge type wedge type can be obtained without being bulky in the height direction.

[0020] When the heat generating part is disposed separately from the discharge electrode !, the discharge part and the heating means can be separately manufactured and assembled, so that the manufacturing yield can be improved and the defect It can be easily disassembled when a fault occurs, and repairs and replacement of worn electrodes (discharge parts) can be performed easily. In addition, since the heat generating portion and the discharge electrode are spaced apart to ensure insulation, there is no need to form a heat generating portion insulating film for insulating the heat generating portion and the discharge electrode. The manufacturing man-hours can be reduced and the mass productivity is excellent.

For the heating means having a heat generating part that heats away from the discharge electrode, a method of irradiating a laser beam or a method of irradiating infrared rays can be suitably used as the heat generating part.

[0021] The invention according to claim 2 is the display device according to claim 1, wherein the printing unit includes: The display device includes a restorer that initializes display content of the display medium and performs a restoration process.

With this configuration, in addition to the operation of claim 1, the following operation is provided.

(1) The display medium can be blanked by the restoring unit of the printing unit, and preprocessing when rewriting the display contents of the display medium is easy and practical.

[0022] As the restoring device, a charging roller, a charging brush, or the like is preferably used. As a result, the surface of the display medium on which a visible image appears due to the action of electric charges inside the device can be uniformly charged to initialize the display medium, and rewriting to the display medium can be repeated. Instead of providing a restorer, unnecessary recording can be erased by irradiating a display medium on which an image has been formed from a heat-discharge type print head with ions having a polarity opposite to that at the time of image formation.

[0023] The invention according to claim 3 is the display device according to claim 1 or 2, wherein the display medium is disposed on a surface opposite to a surface facing the heating-discharge type print head. A ground electrode portion or a positive voltage application portion.

With this configuration, in addition to the operation of the first or second aspect, the following operation is provided.

(1) Between the discharge electrode of the heat discharge type print head and the display medium on the surface opposite to the surface of the display medium on which recording is performed by irradiating ions accompanying discharge from the heat discharge type print head (the back side of the display medium) By providing a ground electrode part for applying an electric field to the electrode or a positive voltage application part for applying a positive voltage, it is possible to reliably irradiate ions from the discharge electrode of the heat discharge type print head toward the display medium. In addition, since the ion irradiation position accuracy can be improved, the unit dots in the display medium can be miniaturized and high-definition image display can be performed.

[0024] Here, when the ground electrode portion and the positive voltage application portion of the display medium are on the display screen side (the surface viewed by a person) of the display device, the ground electrode portion and the positive voltage application portion must be transparent. When the display medium has a liquid crystal shutter function, the ground electrode part and the positive voltage application part can be made transparent to respond to transmitted light instead of reflected light.

[0025] The invention according to claim 4 is the display device according to any one of claims 1 to 3, wherein the display device is disposed on either the front surface side or the back surface side of the display medium. Was It has a light source section and has a configuration.

With this configuration, in addition to the operation of any one of claims 1 to 3, it has the following operation.

(1) When the display screen side (surface viewed by a person) of the display device is on the surface (medium substrate) side of the display medium, a light source unit is arranged on the surface side of the display medium, so that the reflected light of the light source unit force is reflected. You can use it to display images.

(2) The display screen side of the display device (the surface viewed by a person) is the back side of the display medium (the ground electrode section or the positive voltage application section) side, and the medium substrate has a liquid crystal shutter function (a function that transmits and blocks light). If equipped, it can be used as a backlight by disposing a light source on the surface side of the display medium, and keeps the brightness of the display screen at low power using transmitted light from the light source even at night be able to.

(3) The display screen side of the display device (the surface viewed by a person) is the back side of the display medium (the ground electrode section or the positive voltage application section) side, and the medium substrate has a liquid crystal shutter function (a function that transmits and blocks light). When not provided, the display screen can be illuminated by using the reflected light from the light source unit by disposing the light source unit on the back side of the display medium.

[0026] The invention according to claim 5 is the display device according to any one of claims 1 to 4, wherein the display primary color of the display medium is at least the three primary colors (R, G in the additive color mixing method). , B).

With this configuration, in addition to the operation of any one of claims 1 to 4, the following operation is provided.

(1) Since the display primary colors are at least the three primary colors (R, G, B) in the additive color mixture method, the display screen can be colorized by the additive color mixture method using transmitted light.

[0027] Here, when the medium substrate of the display medium has a liquid crystal shutter function and the ground electrode part and the positive voltage application part are transparent, the transmitted light is used by providing a color filter having colors of the three primary colors. Thus, the display screen can be colorized by an additive color mixing method. The display primary color must include at least the three primary colors in the additive color mixing method. Black may be included as necessary.

[0028] The invention according to claim 6 is the display device according to any one of claims 1 to 4, wherein The display primary color of the display medium is at least the three primary colors (Υ, M, C) in the subtractive color mixture method.

(1) By adopting a configuration in which the display primary colors are at least the three primary colors (Y, M, C) in the subtractive color mixture method, the display screen can be colorized by the subtractive color mixture method using reflected light.

Here, reflected light can be used when the display medium includes a reflective layer having the colors of the three primary colors. Irrespective of the presence or absence of the liquid crystal shutter function on the medium substrate of the display medium, irradiation with the medium substrate side force light can cope with the colorization of the display screen by the subtractive color mixture method using the reflected light.

Since the media substrate side is the display screen side of the display device (the surface seen by people), the ground electrode and positive voltage application unit may be transparent or opaque.

The display primary colors must be at least the three primary colors in the subtractive color mixing method, but black or the like may be included as necessary.

[0030] The invention according to claim 7 is the display device according to claim 5 or 6, wherein each of the display primary colors is arranged in a striped pattern on the display medium. And speak. With this configuration, the following actions are taken in addition to the actions of the fifth or sixth aspect. (1) By disposing the display primary colors in a striped pattern, it is possible to easily control the display colors (by combining the respective colors) in the display primary color pixels and prevent color misregistration.

Here, one pixel is divided into three, and the three primary colors (R, G, B) in the additive color mixing method or the three primary colors (Y, M, C) in the subtractive color mixing method are arranged in a striped pattern as a display primary color. Yes.

[0031] The invention according to claim 8 is the display device according to claim 7, wherein the display medium has little in a direction parallel to or orthogonal to a longitudinal direction of the display primary colors arranged in a striped pattern. At least, it has a configuration including an indicator disposed on one of the two sides.

With this configuration, in addition to the operation of the seventh aspect, the following operation is provided.

(1) When an indicator is provided in a direction parallel to the longitudinal direction of the display primary color arranged in a striped pattern, the inclination of the stripe pattern of the display primary color can be known by reading the inclination of the indicator. Color shift can be reduced by strictly controlling the display color (by combining each color) in the pixel.

(2) When the indicators are provided in the direction perpendicular to the longitudinal direction of the display primary colors arranged in a striped pattern, it is possible to know the inclination of the tip of each display primary color when serially scanning the heat-discharge type print head. The occurrence of color misregistration due to serial scanning can be reduced.

(3) When both the indicator arranged in the direction parallel to the longitudinal direction of the display primary color and the indicator arranged in the direction orthogonal to the longitudinal direction of the display primary color are included in each serial scan of the heat discharge type print head Control can be performed in consideration of the inclination of the stripe pattern of the display primary color, and the accuracy of preventing color misregistration can be improved.

Here, the index can be provided in a blank portion of the display medium.

The scanning of the heat-discharge type print head is usually performed along the stripe pattern of the display primary color.

If the inclination of the index is read by moving the heating / discharge type print head in advance before scanning the heating / discharge type print head, the control considering the inclination of the stripe pattern of the display primary color is possible at the actual scanning stage. Become.

In order to read the inclination of the index, for example, a reading device such as a scanner should be provided in conjunction with the movement of the heating / discharge type print head.

[0033] The invention according to claim 9 is the display device according to any one of claims 1 to 4, wherein the entire surface of the display medium or each block unit obtained by dividing the display medium is monochromatic. It has a structure to display.

(1) Instead of using the display colors obtained by combining the colors of the display primary color pixels, the display primary color pixels are displayed by performing a single color display (monocolor display) on the entire surface of the display medium or in units of blocks obtained by dividing the display medium. Compared with the display color by combining each color in, the sharpness of the image can be improved.

Here, the display medium may perform monochromatic display on the entire surface of the display medium, or may perform monochromatic display of different colors in units of blocks obtained by dividing the display medium. The display colors for single color display are the display primary colors (R, G, B) in the additive color mixture method and the display primary colors (in the subtractive color mixture method ( Y, M, and C) can be arbitrarily selected. Since the monochrome display includes black (monochrome) display, it can be said that the monochrome display is obtained by replacing the color of the black display with another color.

When performing single color display in each block unit, the display medium is divided into a plurality of blocks, and an arbitrary display color is assigned in each block unit. For example, when the entire display medium is divided into three, the display primary colors (R, G, B) in the additive color mixing method and the display primary colors (Y, M, C) in the subtractive color mixing method are assigned to each block one by one. Single color display can also be performed in units.

The invention according to claim 10 is the display device according to any one of claims 1 to 9, wherein the printing unit moving means for moving the printing unit or the display medium conveying means for conveying the display medium At least one of these is provided with a configuration having one of them.

With this configuration, in addition to the operation of any one of claims 1 to 9, the following operation is provided.

(1) When the printing unit moving means is provided, the image can be written at an arbitrary position on the fixed display medium by moving the printing unit.

(2) When the display medium is fixed and the printing unit is moved, the display device only requires a sheet-type display medium having a display screen size, so that the display medium can be saved.

(3) In the case of having a display medium transport means, it is possible to write an image while moving the display medium, and display the image by moving the area on the display medium where a new image is formed to the display screen. can do.

(4) When both the printing unit moving unit and the display medium conveying unit are provided, the relative conveying speed can be improved by moving the printing unit and the display medium in the opposite directions, and the time required for image formation can be increased. It can be shortened.

(5) When both the printing unit moving unit and the display medium conveying unit are provided, the image is switched when the printing unit is moved and the writing of the image to the fixed display medium is completed. It can be performed. In particular, if a display medium formed in an endless loop (closed loop) shape of infinite length or a sheet (open loop) shape of finite length equal to or larger than the size of the display screen is used, images are displayed on the display screen. In the meantime, the next image to be displayed can be written in the non-display area of the display medium. Here, as the printing unit moving unit, the same moving unit as used in the conventional image forming apparatus is preferably used.

If the heat-discharge type print head or restorer has a width that can accommodate the width of the display medium, the print medium moving means can scan the display medium in a direction that moves the print section relative to the display medium. You can write an image on When the display screen of the display device is enlarged, if the width of the heat discharge type print head or the restoring device is narrower than the width of the display medium, the printing unit moving means is caused to perform serial scanning on the printing unit. As a result, the problem of the width of the heat discharge type print head and the restoring device can be solved, and an image can be formed over the entire width of the display medium.

As the display medium transporting means, any means that can move the display medium relative to the printing unit is used. An image can be formed by rotating an endless loop (closed loop) display medium or sliding a finite-length sheet (open loop) display medium.

[0037] The invention according to claim 11 is the display device according to claim 10, wherein (a) the display medium conveying means includes at least two rollers and at least one of the rollers. And (b) the display medium is wound around in an endless loop around the roller.

With this configuration, in addition to the operation of the tenth aspect, the following operation is provided.

(1) Since the display medium transport means includes at least two rollers and a roller driving unit that rotates at least one of the rollers, an endless loop-shaped display medium wound around the rollers is provided. The image can be revolved and moved, and the image can be rewritten by the fixed printing unit and the formed image can be moved.

(2) Since the display medium is wound in an endless loop around the roller, if it has a printing unit moving means to move the printing unit, it is used for switching to the non-display area of the display medium during image display. The image can be written.

[0038] Here, as the display medium transporting means, one that can transport the display medium by an arbitrary amount of movement by rotating a roller by a roller driving unit such as a motor is preferably used. Since the display medium is arranged in an endless loop, an image is displayed on the display device. In the meantime, it is possible to write an image on the display medium on the back side of the display device or inside the ring of the endless loop display medium.

The image can be switched, for example, by a timer or at the end of writing of the heat discharge type print head. When switching images using a timer, it is possible to automatically switch images by setting an image switching interval that is longer than the time required to write an image with a heating and discharging type print head. When switching the image at the end of writing of the heating and discharging type print head, if the movement of the heating and discharging type print head by the printing unit moving means is monitored, the image will be immediately displayed at the end of writing of the image. Switching can be performed and waiting time can be shortened.

Note that the image switching can be performed so that the entire display screen can be switched at once after writing of the entire image is completed, or writing is completed each time the heating / discharge type print head writes one or more lines. It is possible to move only part of the display intermittently so that the display screen is gradually changed.

An image display method for a display device according to claim 12 includes: (a) an image forming step of writing an image for switching on the display medium during image display of the display device according to claim 11; And an image switching step of switching between the image being displayed on the display device formed on the display medium and the image for switching.

This configuration has the following effects.

(1) Since it has an image forming step of writing an image for switching on the display medium during image display of the display device, it is possible to write an image on a stopped display medium that is displaying an image. .

(2) Since there is an image switching step for switching between the image being displayed on the display device formed on the display medium and the image for switching, the switching image formed in the image forming step of the previous step is displayed on the display device. Images can be switched by moving to the screen side.

(3) By repeating the image forming process and the image switching process, it is possible to sequentially switch still images, so that even if the display device has a large screen, power saving and quick switching of still images are possible. If it is used instead of a movie sign, a still image of a representative scene can be rewritten and displayed periodically or irregularly. The invention's effect

[0040] As described above, according to the display device and the image display method of the present invention, the following advantageous effects can be obtained.

According to the invention described in claim 1, the following effects are obtained.

(1) To provide an energy-saving display device that can hold an image written on a display medium with a heat-discharge-type print head and retains the image without consuming any power just as it is printed on printing paper. be able to.

(2) In a heat-discharge type print head, the discharge electrode to which a discharge control voltage (a voltage range in which discharge does not occur but is generated by heating only) is applied is controlled by calorie heating means. As a result, when thermoelectrons are emitted from the heated discharge electrode, discharge and light emission occur, and the ion generation amount can be controlled in an atmosphere where ions can be generated. It is possible to provide a display device excellent in energy saving that can perform recording on a display medium such as a digital paper.

(3) Since the amount of ions generated and the emission intensity associated with the discharge from the heat-discharge type print head can be easily controlled by the heating control, the area gradation on the display medium can be easily performed, and the image of the display medium A high-quality and highly reliable display device that can improve quality can be provided.

[0041] According to the invention described in claim 2, in addition to the effect of claim 1, the following effect is obtained.

(1) It is possible to provide a display device excellent in practicality that can perform blanking of the display medium with the restoring unit of the printing unit and can easily perform pre-processing when rewriting the display content of the display medium.

[0042] According to the invention of claim 3, in addition to the effect of claim 1 or 2, it has the following effect.

(1) Between the discharge electrode of the heat discharge type print head and the display medium on the surface opposite to the surface of the display medium on which recording is performed by irradiating ions accompanying discharge from the heat discharge type print head (the back side of the display medium) By providing a ground electrode part for applying an electric field to the electrode or a positive voltage application part for applying a positive voltage, it is possible to reliably irradiate ions from the discharge electrode of the heat discharge type print head toward the display medium. Can improve the accuracy of ion irradiation position and make it a display medium. It is possible to provide a high-definition display device capable of miniaturizing unit dots.

[0043] According to the invention of claim 4, the effect of any one of claims 1 to 3 is achieved, and the following effects are obtained.

(1) Images can be displayed using reflected or transmitted light from the light source unit depending on the type of display medium and whether the display screen side (the surface viewed by a person) is front or back of the display medium! A display device with excellent practicality can be provided.

[0044] According to the invention of claim 5, the effect of any one of claims 1 to 4 is reduced, and the following effects are obtained.

(1) Since the display primary colors are at least the three primary colors (R, G, B) in the additive color mixture method, a display device with excellent functionality that can support colorization of the display screen by the additive color mixture method using transmitted light. Can be provided.

[0045] According to the invention of claim 6, the effect of any one of claims 1 to 4 is reduced, and the following effects are obtained.

(1) By configuring the display primary colors to be at least the three primary colors (Y, M, C) in the subtractive color mixture method, it has excellent functionality that can support colorization of the display screen by the subtractive color mixture method using reflected light. A display device can be provided.

[0046] According to the invention of claim 7, in addition to the effect of claim 5 or 6, it has the following effect.

(1) By arranging the display primary colors in a striped pattern, it is easy to control the display colors (by combining each color) in the display primary color pixels, and it has excellent reliability and practicality that can prevent color misregistration. A display device can be provided.

[0047] According to the invention described in claim 8, in addition to the effect of claim 7, the following effect is obtained.

(1) It is possible to know the inclination of the stripe pattern of the display primary color by the index provided in the direction parallel to the longitudinal direction of the display primary color arranged in a striped pattern, and the display color in the display primary color pixel (by combining each color) It is possible to provide a display device excellent in reliability and practicality capable of reducing color misregistration by strictly controlling the above.

(2) Each indicator is provided by an indicator provided in the direction perpendicular to the longitudinal direction of the display primary colors arranged in a striped pattern. It is possible to provide a display device with excellent reliability and practicality that can know the inclination of the leading edge of the display primary color and can reduce the occurrence of color misregistration due to serial scanning of the heat-discharge type print head.

(3) When both the indicator arranged in the direction parallel to the longitudinal direction of the display primary color and the indicator arranged in the direction orthogonal to the longitudinal direction of the display primary color are included in each serial scan of the heat discharge type print head It is possible to provide a display device with excellent reliability and functionality that can perform control in consideration of the inclination of the stripe pattern of the display primary color and can improve the accuracy of color misregistration prevention.

[0048] According to the invention of claim 9, the effect of any one of claims 1 to 4 is reduced, and the following effects are obtained.

(1) The entire surface of the display medium is a single color display (mono-color display) for each block obtained by dividing the display medium, thereby combining the colors in the display primary color pixels of the additive color mixing method and subtractive color mixing method. Compared with the display color by, a display device with clear images and excellent visibility can be provided.

[0049] According to the invention of claim 10, the effect of any one of claims 1 to 9 is as follows.

(1) Practicality that the display medium can be moved relatively by driving at least one of the printing unit moving means and the display medium conveying means, and the image can be written on the display medium. A display device with excellent functionality can be provided.

(2) In the case of having both the printing unit moving means and the display medium transport means, the display medium is formed into an infinitely long endless loop (closed loop) shape or a finite length sheet (open loop) shape that is equal to or larger than the size of the display screen By using, the image to be displayed next can be written in the non-display area of the display medium by moving the print part while the image is displayed on the display screen, and the display medium is displayed after the writing is completed. It is possible to provide a display device excellent in practicality and functionality that can switch images by moving the screen.

[0050] According to the invention of claim 11, in addition to the effect of claim 10, the following effect is obtained.

(1) The endless loop display medium can be moved by the display medium transport means. Thus, the switching image can be written in the non-display area of the display medium that is displaying the image, and when the image writing is completed, the display medium can be transported to display the switching image. It is possible to provide a display device that is practical and versatile.

[0051] According to the invention of claim 12, it has the following effects.

(1) By repeating the image forming process and the display medium moving process, it is possible to switch still images in sequence, so that even if the display device has a large screen, power saving and quick switching of still images are possible. If it is used instead of a movie signboard, it is possible to rewrite and display a still image of a representative scene regularly or irregularly. Can be provided.

Brief Description of Drawings

[0052] FIG. 1 is a schematic diagram of a main part showing a configuration of a display device in a first embodiment.

2A is a schematic side view showing a heat discharge type print head of the display device in Embodiment 1. FIG. 2B is a schematic perspective view showing a main part of the heat discharge type print head of the display device in Embodiment 1. is there.

FIG. 3 is a plan development view of the main part of the head substrate of the heat discharge type print head of the display device in the first embodiment.

4 is a cross-sectional view taken along line AA in FIG. 3 (b) is a cross-sectional view taken along line BB in FIG.

FIG. 5 is an exploded perspective view of the main part of the head substrate of the heat discharge type print head of the display device in the first embodiment.

FIG. 6 is a configuration diagram of a discharge control device for a heat discharge type print head of the display device in the first embodiment.

FIG. 7 is a perspective view showing a heating part forming step of the head substrate of the heat discharge type print head of the display device in the first embodiment.

FIG. 8 is a perspective view showing a discharge portion forming step of the head substrate of the heat discharge type print head of the display device in the first embodiment.

FIG. 9 is a schematic cross-sectional view of the relevant part showing the display device in the first embodiment.

FIG. 10 (a) Schematic exploded view showing the configuration of one pixel of the display medium of the display device in the first embodiment (b) Display primary colors and indices of the display medium of the display device in the first embodiment It is a plane perspective view which shows arrangement | positioning.

FIG. 11 is a schematic exploded view of a main part of one pixel showing a first modification of the display medium of the display device in the first embodiment.

圆 12] A schematic plan view showing a second modification of the display medium of the display device in the first embodiment.

FIG. 13] A schematic rear view of a main part showing a modification of the display device in the first embodiment.

FIG. 14 (a) Schematic cross-sectional view of relevant parts showing a display device in the second embodiment (b) Embodiment

2 is a schematic exploded view of a main part showing a configuration of one pixel of a display medium of a display device in FIG. FIG. 15 is a schematic cross-sectional view showing a main part of a display device in a third embodiment.

FIG. 16 is a schematic cross-sectional view showing a main part of a display device in a fourth embodiment.

FIG. 17 is a schematic cross-sectional view of a relevant part showing a modification of the display device in the fourth embodiment. Explanation of symbols

1, la, lb, lc, Id, le display

2 Print section

3 Heating discharge type print head

4 Restorer

5, 5a, 5b, 5c Display media

6 Media substrate

6a Media substrate surface

6b Media board body

6c color filter

6d reflective layer

7, 7b Ground electrode

7a Ground electrode surface

8a, 8b indicator

10 Heat sink

11 Board

11a End face 12 Head substrate

13 Discharge section

13a Discharge electrode

13b Common electrode

14 Driver IC

15 Discharge control device

16 Printed circuit board

17 Connector

18 IC cover

18a High voltage substrate

19 Common conductor for heating

19a Comb electrode for heating

19b Common electrode for heat generation

20 Individual electrode for heat generation

20a Bonding pad I

21 Heating part

21a Heating element

21b Heat-generating part insulation film

22 Discharge generator

23 Heating means

24a, 24b Light source

25a, 25b roller

26 Control unit

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1)

A display device and an image display method thereof according to Embodiment 1 of the present invention will be described below with reference to the drawings.

FIG. 1 is a main part schematic diagram showing the configuration of the display device in the first embodiment. In FIG. 1, 1 is a display device according to Embodiment 1 of the present invention, 2 is a printing unit of the display device 1, 3 is a heat-discharge type print head of the printing unit 2, 4 is a medium substrate 6 of a display medium 5 described later, Medium Restoration device for printing section 2 that uniformly charges substrate surface 6a, 5 is a display medium for display device 1 such as a digital paper in which a visible image appears due to the action of electric charges generated by the discharge of heating discharge print head 3 , 7 is a ground electrode portion for applying an electric field between the heating discharge type print head 3 and the display medium 5 disposed on the back side of the display medium 5 (the side opposite to the side facing the heating discharge type print head 3). 7a is a surface of the ground electrode portion.

The heat-discharge type print head 3 forms an image by moving relative to the display medium 5. If the display medium 5 is a finite-length sheet (open loop), the heat-discharge type print head 3 It is preferable to move the display medium 4 if the display medium 4 is in an endless loop (closed loop) of infinite length. Although FIG. 1 shows the case where the display medium 5 is in the form of a sheet (open loop) and the heating / discharge type print head 3 moves, an image is displayed on the display medium 5 even when the display medium 5 is moved. The principle of formation is the same. Depending on the polarity of the applied voltage, the heat-discharge type print head 3 can irradiate either positive or negative ions during discharge, but here, writing is performed from the medium substrate surface 6a side of the display medium 5 by negative ion irradiation. The case will be described.

According to the heat-discharge type print head 3, it is possible to form an image by oxidation-reduction reaction in addition to the formation of an electrostatic latent image. In addition, light emission accompanying discharge can be recorded on a digital paper or the like using a photochromic compound that forms an image with ultraviolet rays or visible rays.

Next, a procedure for rewriting an image written on the display medium 5 will be described.

First, the restorer 4 of the printing unit 2 uniformly charges the surface of the display medium 5 with a polarity opposite to that at the time of image writing. As a result, it is possible to perform a restoration process in which all the display contents of the display medium 5 are erased and initialized (returned to a blank sheet state). As the restoring device 4, a charging roller, a charging brush, or the like is preferably used.

Next, when ion irradiation is performed by the heat-discharge type print head 3, a visible image appears on the display medium 5 due to the effect of electric charges.

In order to apply an electric field to the display medium 5 connected to the heating / discharge type print head 3, the display medium 5 A ground electrode portion 7 is provided on the back side (the side opposite to the image writing side). It seems that applying an electric field promotes the effect of electric charge, and in the portion of the display medium 5 where the electric field is strong, it is possible to make a visible image appear on the display medium 5 reliably using the energy of the electric charge. wear.

[0057] As described above, as a pre-processing for rewriting the display content of the display medium 5, instead of using the force restorer 4 that needs to perform the restoration process of the display medium 5, the heating discharge type print head 3 The display medium 5 may be traced by irradiating positive ions having a reverse polarity to that during image formation. As a result, the image being displayed on the display medium 5 can be blanked (initialized) and erased. As a measure to prevent misalignment when tracing using the heat-discharge type print head 3, a region wider than the region of the image once written, for example, an extended tracing region expanded by a certain width is reversed. Just follow the polarity.

Next, details of the heat-discharge type print head will be described.

FIG. 2 (a) is a schematic side view showing the heat discharge type print head of the display device in the first embodiment, and FIG. 2 (b) shows the heat discharge type print head of the display device in the first embodiment. It is a principal part model perspective view.

In FIG. 2, 10 is a heat dissipation plate of the heat-discharge type print head 3 made of a material such as aluminum, 12 is a substrate 11 made of ceramic, etc. The head substrate of the heated discharge type print head 3, 13 a is a plurality of discharge electrodes of the discharge part 13 formed in a comb-teeth shape, 13 b is a common electrode of the discharge part 13 connecting one end of the discharge electrode 13 a, 15 is Heat discharge type print head 3 discharge control device with head substrate 12 and driver IC14, 16 is a printed wiring board disposed on heat sink 10 with connector 17 for electrical connection to the outside, 18 is driver An IC cover 18a is provided to protect the IC 14 and the printed wiring board 16. The discharge electrode is connected to the common electrode 13b of the discharge part 13 by electric wiring (not shown) disposed on the back surface of the IC cover 18. This is a high voltage substrate that supplies high voltage to 13a.

Next, details of the structure of the head substrate will be described.

FIG. 3 is a plan development view of the main part of the head substrate of the heat-discharge type print head of the display device according to Embodiment 1, and FIG. 4 (a) is a cross-sectional view taken along line AA in FIG. (b) is shown in Fig. 3. FIG. 5 is a cross-sectional view taken along the line B-B, and FIG. 5 is an exploded perspective view of the main part of the head substrate of the heat discharge type print head of the display device in the first embodiment.

In FIGS. 3 to 5, 19 is a heating common conductor pattern formed on the upper surface of the substrate 11 connected to the plurality of heating comb electrodes 19a, and 19b is arranged on the upper surface of the heating common conductor pattern 19. Common electrode for heat generation, 20 is an individual electrode for heat generation formed on the upper surface of the substrate 11 alternately with the comb-shaped electrode for heat generation 19a, 20a is a bonding pad formed at the end of the individual electrode for heat generation 20, and 21 is a discharge Heat generating part of the control device 15, 21a is a heating element of the heat generating part 21 formed by being electrically connected to the upper part of the comb electrode 19a for heating and the individual electrode 20 for heating, 21b is a common electrode 19b for heating and an individual for heating A heat generating portion insulating film 22 covered on the upper surface of the substrate 11 except for the end portion of the electrode 20, 22 is a discharge generating portion of the discharge electrode 13a that generates a discharge when heated by the heat generating element 21a.

The above-described discharge part 13 is insulated from the heat generating element 21a by the heat generating part insulating film 21b, and a plurality of discharge electrodes 13a are formed to face the heat generating element 21a corresponding to the position of the individual electrodes 20 for heat generation.

Next, the configuration of the discharge control device will be described in detail.

FIG. 6 is a configuration diagram of the discharge control device for the heat discharge type print head of the display device according to the first embodiment.

In FIG. 6, the head substrate 12 has a discharge part 13 and a heat generation part 21. The heating means 23 controls the heat generation of the heating element 21a of the heat generating portion 21 by the driver IC 14 electrically connected to the heat generating portion 21. It is the discharge control device 15 of the heat discharge type print head 3 that controls the discharge from the discharge electrode 13a by controlling the heating of the discharge portion 13 to the discharge electrode 13a by the heating means 23.

In addition, by disposing the heat radiating plate 10 on the head substrate 12, the heat generated in the heat generating portion 21 can be quickly absorbed by the heat radiating plate 10 and radiated from the heat radiating plate 10. As a result, the heat generating portion 21 can be rapidly cooled to improve the response to the heating stop. In addition, the driver IC 14 can be protected from heat and has excellent reliability. When irregularities are formed on the surface of the heat sink 10 by grooves or the like, the surface area of the heat sink 10 can be increased, and the efficiency of heat dissipation can be improved. Next, a method for manufacturing the head substrate will be described in detail.

FIG. 7 is a perspective view showing a heating part forming step of the head substrate of the heat discharge type print head of the display device in the first embodiment, and FIG. 8 is a diagram of the heat discharge type print head of the display device in the first embodiment. It is a perspective view which shows the discharge part formation process of a head substrate.

First, the heating part forming step will be described.

In FIG. 7, a plurality of heat generating comb-teeth electrodes connected by a heat generating common conductor pattern 19 after printing a conductor such as a gold paste on the surface of a substrate 11 formed in a long plate shape with ceramic or the like, by etching. 19a and individual electrodes 20 for heat generation are formed. After that, a strip shape is printed by printing TaSiO, RuO, etc. on top of the comb electrode 19a for heating and the individual electrode 20 for heating.

twenty two

The heating element 21a is formed. Further, the heat generating common electrode 19b is formed on the upper surface of the heat generating common conductor pattern 19 by printing silver paste or the like.

[0062] Bonding pads 20a were formed on the end portions of the individual heating electrodes 20. This facilitates connection to the driver IC 14 by wire bonding.

The heating means 23 is preferably configured in the same manner as a thermal print head used in a conventional thermal facsimile. In this case, the manufacturing process of the existing thermal print head can be followed, and the discharge control device 15 can be manufactured at low cost by diverting the manufacturing device.

In the present embodiment, the heating element 21a of the heating part 21 is formed in a strip shape, the heating comb electrodes 19a and the heating individual electrodes 20 are alternately arranged, and one heating individual electrode 20 in each center. Between the heat generating comb electrodes 19a on both sides of the discharge electrodes 13a, and selectively generate heat at any part of the heating element 21a corresponding to the position of the discharge generating part 22 of each discharge electrode 13a. The force for heating 13a is not limited to this, and any structure that can selectively heat the discharge generating portion 22 of each discharge electrode 13a may be used. In addition to the heating means 23 that heats the heat generating portion 21 by insulating and intimately contacting the discharge electrode 13a, it is also possible to use a heating means that uses a laser or infrared ray that heats the discharge electrode 13a apart from the discharge electrode 13a as the heat generating portion 21. The

Next, the discharge part forming step will be described.

In FIG. 8, the bases except for the ends of the heating common electrode 19b and the heating individual electrode 20 are the same. The heat generating portion insulating film 21b is formed on the surface of the plate 11 by printing an insulator such as glass, ceramic, My strength, or synthetic resin. The heat generating part insulating film 21b may be any material that can protect and insulate the heat generating common electrode 19b, the heat generating individual electrode 20, the heat generating element 21a, etc., but efficiently transfer the heat of the heat generating element 21a to the discharge electrode 13a. Can be SiAl, SiO, SiC, polyimide, aluminum

2

Those having high thermal conductivity such as imide are preferably used.

The optimum film thickness of the heat-generating portion insulating film 21b depends on the material, but when it is made of glass, it is formed to 4 m to 40 μm. Insulation tends to decrease as the thickness of the heat-generating part insulating film 2 lb becomes thinner than 4 μm, and as the thickness exceeds 40 m, the applied voltage applied to the discharge part 13 and the heating value of the heating element 21a are reduced. This is because it is necessary to increase the energy consumption and it tends to decrease the energy saving performance. By setting the thickness of the heat generating part insulating film 2 lb to 4 m to 40 m, the insulation and thermal conductivity are harmonized and both are excellent and the discharge stability is excellent. If it is performed in multiple steps, even if pinholes are generated by each application, the possibility of pinholes overlapping can be reduced, and the heat generating part 21 can be reliably insulated, so it is reliable. Excellent in properties.

[0064] Next, a plurality of discharge electrodes 13a facing the heat generating individual electrodes 20 of the heating means 23 and a common electrode 13b connecting them are formed on the heat generating portion insulating film 21b. For the formation of the discharge electrode 13a and the common electrode 13b, a metal such as gold, silver, copper, or aluminum formed by vapor deposition or sputtering printing and then etched to form a pattern is suitably used. In addition, a conductive material such as carbon may be used.

In the present embodiment, the discharge electrode 13a is formed in a substantially rectangular shape, but it can be formed in a trapezoidal shape, a shell shape, a semicircular shape, or a combination thereof. Further, since the discharge generating portion 22 of the discharge electrode 13a has a large amount of discharge from the periphery of the edge, a plurality of uneven portions may be formed on the outer peripheral edge of the discharge electrode 13a so that the peripheral length of the periphery of the edge becomes long. The amount of ion irradiation can be increased by increasing the amount of discharge generated by the discharge generator 22, and the discharge controller 15 is excellent in energy saving and efficiency. In addition, since the voltage applied to the discharge electrode 13a can be set small, the life of the discharge electrode 13a is excellent.

[0065] Of the discharge part 13, the vicinity of the heating position by the heat generating part 21 of the heating means 23 is the discharge generating part 22. However, the discharge part 13 may be covered with a coating film except for the discharge generation part 22. By forming the coating film excluding the discharge generating portion 22 of the discharge electrode 13a, a step can be formed between the surface of the discharge generating portion 22 and the surface of the coating film. Therefore, the gap between the discharge electrode 13a and the display medium 5 disposed so as to be opposed can be kept constant, so that the discharge from the discharge electrode 13a can be stabilized. It is possible to prevent the display medium 5 from coming into contact with the discharge generation part 22 of the discharge electrode 13a, and the reliability is excellent.

The end face type heat discharge type print head 3 shown in FIG. 2 is characterized by being on the end face portion 1 la of the substrate 11 on which the discharge generating portion 22 1S driver IC 14 of the discharge electrode 13a is disposed. Even when the heat-discharge type print head 3 is arranged so that the surface of the discharge electrode 13a is substantially parallel to the display medium 5, the display medium 5 and the driver IC 14 or IC cover 18 do not interfere with each other. Since an image can be written in a state orthogonal to the display medium 5, it can be said that it has an optimum shape for use in the display device 1.

In addition, when forming an image by scanning the heat-discharge type print head 3, the heat-discharge type print head 3 and the high-voltage board 18a can be moved together. Can be reduced.

In this embodiment, the substrate 11 is formed in a flat plate shape. However, the substrate 11 is formed in a substantially L shape or a square shape by bending the end surface portion 11a of the substrate 11 to the surface side of the substrate 11 or the like. But ヽ. Further, the arrangement of the discharge electrodes 13a may be an edge type in which the discharge electrodes 13a are arranged on the edge of the substrate 11 on which the driver ICs 14 are arranged. Since the discharge electrode 13a is arranged on the edge of the substrate 11 which is chamfered in an inclined manner, it is easy to manufacture and excellent in productivity, and the driver IC 14 and the discharge electrode 13a form an obtuse angle, so that the end face is not bulky in the height direction. The same effect as the mold can be obtained.

[0067] Next, details of the display device will be described.

FIG. 9 is a schematic cross-sectional view of a main part showing the display device in the first embodiment. In FIG. 9, 24 a is a light source unit disposed on the medium substrate 6 side of the display medium 5, and 24 b is a light source unit disposed on the ground electrode unit 7 side of the display medium 5.

The display device 1 shown in FIG. 9 has a configuration in which a sheet type display medium 5 is fixed and the printing unit 2 is moved to form an image on the display medium 5. When the display medium 5 is fixed as described above, A display medium transport means for transporting the display medium 5 is not required, and the display device 1 can be downsized, and the entire display medium 5 having a size substantially the same as the display screen of the display device 1 can be effectively used without waste. Images can be written and the display medium 5 can be saved. In the display device 1, since the ground electrode portion 7 of the display medium 5 is on the display screen side (a surface viewed by a person) of the display device 1, the ground electrode portion 7 must be transparent. As will be described later, when the medium substrate 6 has a liquid crystal shutter function (function of passing and blocking light), the light source 24a is placed behind the display screen of the display medium 5 (medium substrate 6 side) as shown by the solid line. If used as a backlight, the brightness of the display screen can be maintained at low power by using the transmitted light from the light source 24a even at night. If the display medium 5 does not have a liquid crystal shutter function, the light source unit 24b is installed on the display screen side (ground electrode unit 7 side) of the display medium 5 as shown by the broken line. The display screen can be illuminated using the reflected light.

In addition, since the printing unit 2 is arranged on the back side of the display screen of the display device 1 (the side opposite to the surface seen by humans), the printing unit 2 can be hidden inside the display device 1 so that no external force can be seen. The appearance of the display device 1 can be improved.

Next, details of the display medium will be described.

First, the configuration of the pixels of the display medium will be described.

FIG. 10 (a) is a schematic exploded view of the main part showing the configuration of one pixel of the display medium of the display device in the first embodiment.

In Fig. 10 (a), 6b is the substrate body of the medium substrate 6 having a liquid crystal shutter function, and 6c is a striped pattern of the three primary colors (R, G, B) in the additive color mixing method as one display pixel divided into three pixels. This is a color filter of the medium substrate 6 arranged in the above. The ground electrode portion 7 is transparent. Since the ground electrode portion 7 is transparent, the liquid crystal shutter function of the substrate body 6b can be utilized to control the passage and blocking of light in the entire display medium 5. This is the same as the method of colorizing the liquid crystal, and a desired color can be displayed using the transmitted light from the light source unit 24a in units of pixels.

When using transmitted light, at least the three primary colors in the additive color mixing method are required as the display primary color, but black or the like may be included as necessary. Of course, if it becomes four colors, it can be placed on the media substrate 6. Each pixel is divided into four, and a color filter in which four display primary colors are arranged is made to correspond.

In this embodiment, by arranging the display primary colors in a striped pattern, it is easy to control the display colors (by combining the colors) in the display primary color pixels, and the power of the display primary colors is prevented. The arrangement is not limited to this, and other arrangement methods such as a staggered pattern may be used.

[0069] Next, the arrangement of display primary colors and indices on the display medium will be described.

FIG. 10 (b) is a plan perspective view showing the arrangement of display primary colors and indices on the display medium of the display device in the first exemplary embodiment.

In FIG. 10B, 8a and 8b are arranged in the marginal part of the substrate surface 6a of the substrate body 6b in the display medium 5 in the longitudinal direction parallel to the longitudinal direction of the display primary color of the color filter 6c and in the orthogonal direction to the longitudinal direction of the display primary color, respectively. This is an index for alignment of the installed heat-discharge type print head 3.

Here, the three primary colors (R, G, B) in the additive color mixing method are taken as the display primary colors, such as four primary colors including black, and the display primary colors are those of the three primary colors (Υ, M, C) in the subtractive color mixing method. In the case, etc., the arrangement of the indicators 8a and 8b is the same.

The reason why the indicator 8a is provided along the stripe pattern of the display primary color in the margin of the substrate surface 6a of the display medium 5 is to know the inclination of the stripe pattern of the display primary color by reading the slope of the indicator 8a. In order to read the inclination of the index 8a, for example, a scanner should be provided in conjunction with the movement of the heating / discharge type print head 3.

[0070] Scanning of the heat-discharge type print head 3 for writing an image on the display medium 5 is usually performed along a stripe pattern of the display primary color. Prior to scanning of the heating / discharging print head 3, if the inclination of the index 8a is read by moving the heating / discharging print head 3 in advance, the inclination of the stripe pattern of the display primary color is taken into account at the actual scanning stage. Control becomes possible. Since the display color (by combining each color) can be controlled precisely in the display primary pixel, color shift can be prevented as much as possible.

By providing the index 8b perpendicular to the stripe pattern of the display primary colors, the inclination of the tip of each display primary color can be corrected when the heating / discharge type print head 3 is serially scanned. By providing both the indicators 8a and 8b, it is possible to perform control in consideration of the inclination of the stripe pattern of the display primary color for each serial scanning of the heating / discharge type print head 3, and improve the accuracy of color misregistration prevention. be able to.

Next, a modified example of the display medium will be described.

The display medium 5a of the first modified example in FIG. 11 is different from the first embodiment in that the medium substrate 6 has a liquid crystal shutter function (function to pass / block light)! / One pixel is divided into three on the substrate 6 and the three primary colors (Y, M, C) in the subtractive color mixing method are arranged in a striped pattern as display primary colors. The ground electrode portion 7 may be transparent or opaque as in the first embodiment.

The display medium 5a displays the color of the entire display medium 5a using the reflected light of the medium substrate 6. The display primary colors (Y, M, C) of the medium substrate 6 are formed by, for example, a twist ball capsule or an electrophoretic capsule having the colors of the three primary colors. Then, a desired color using reflected light from the light source unit 24b is displayed in pixel units.

[0072] When using reflected light, at least the three primary colors in the subtractive color mixing method are necessary as the display primary colors, but black or the like may be included as necessary. Of course, if four colors are used, the pixels on the medium substrate 6 are divided into four to correspond to the medium substrate on which the four display primary colors are arranged. If the size of a pixel such as a twist ball capsule or an electrophoretic capsule with a color larger than that of one pixel is coarse, the resolution of the heat-discharge type print head 3 matches the size of one pixel of the display medium 5a. A plurality of twist ball capsules, electrophoresis capsules, or the like may be arranged per pixel.

FIG. 12 is a schematic plan view showing a second modification of the display medium of the display device in the first embodiment.

The display medium 5b of the second modified example in FIG. 12 is different from the first modified example in that the entire display medium 5b is replaced with three instead of using the display colors obtained by combining the colors of the display primary color pixels. As shown by hatching, different display colors for monochromatic display (monochromatic display) are assigned to the entire pixels of each block as shown by hatching. Black display (monochrome display) is a type of monochromatic display, and monochromatic display can be said to be a black display (monochrome display) with a different color.

By making the entire pixel a single color display, the sharpness can be improved compared to the display color obtained by combining the colors of the display primary color pixels.

In Fig. 12, the display medium 5b is divided into three blocks and different display colors are arranged for each block. The number of divisions of the display medium 5b and the display color displayed in each divided block can be arbitrarily selected. it can. For example, each block unit is assigned the same display color (Y, M, C) as the display primary color in the subtractive color mixture method, or the same display color (R, G, B) as the display primary color in the additive color mixture method. Mono-color display can also be performed in block units. Further, a single color display with the same display color may be performed on the entire surface of the display medium 5b.

Next, a modified example of the display device will be described.

FIG. 13 is a schematic rear view of an essential part showing a modification of the display device in the first embodiment. The display device la of the modified example in FIG. 13 is different from the first embodiment in that it includes two printing units 2.

By providing two printing sections 2, it is possible to write in parallel with a plurality of heat discharge type print heads 3 and to improve the writing speed of the image on the display medium 5. Display of display device la The time required for screen rewriting can be shortened, and the switching time of still images can be shortened.

Also, one heating / discharging print head 3 can be used for image writing, and the other heating / discharging print head 3 can be used for erasing images. In that case, the restorer 4 can be dispensed with.

As described above, the display device according to Embodiment 1 has the following effects.

(1) Since the print unit 2 includes the heat-discharge type print head 3, an image can be recorded on a display medium 5 such as a digital paper where a visible image appears due to the action of discharge. (2) The image written on the display medium 5 by the heat-discharge type print head 3 can be held without any power consumption as in the case of printing on the printing paper, and is excellent in energy saving.

(3) In the heat-discharge type print head 3, the discharge means 13a is applied by the heating means 23 to which a discharge control voltage (which means a voltage range in which discharge does not occur but is generated by heating) is applied. By controlling the heating, thermoelectrons are emitted from the heated discharge electrode 13a, and discharge and light emission occur. In an atmosphere where ions can be generated, the amount of ions generated can be controlled. Recording can be performed on a display medium 5 such as a paper.

(4) Since the amount of ions generated and the light emission intensity associated with the discharge from the heat-discharge type print head 3 can be controlled by the heating control, the area gradation on the display medium 5 becomes easy and the image quality is improved. Can do.

(5) Since the heating means 23 includes the heat generating part 21 having the heat generating element 21a and the driver IC 14 for controlling the heat generation of the heat generating element 21a, the heat generating element 21a generates heat by controlling the heat generation at a low voltage. The discharge electrode 13a corresponding to the heating element 21a can be heated, and image recording can be easily controlled and has excellent practicality.

(6) Since the heat generating part 21 of the heating means 23 is in close contact with the discharge electrode 13a via the heat generating part insulating film 21b, the heating means 23 and the discharge part 13 can be handled as one body, and the heat discharge type printing The handle 3 is easy to handle and the display device 1 is easy to assemble.

(7) Since the heat generating part insulating film 21b is covered with the heat generating part 21 of the heating means 23, the heat generating part 21 can be brought into close contact with the discharge electrode 13a, and the power consumption required for image recording can be reduced and energy saving can be achieved. Excellent in properties.

(8) Since it has the heating means 23, it can be discharged by always applying a discharge control voltage to the discharge part 13 and applying a low heat generation temperature of the heating element 2 la to the discharge electrode 13a. Excellent energy saving.

(9) By having the high voltage substrate 18a electrically connected to the discharge part 13, the electric wiring for applying the discharge control voltage can be shortened, and the reliability can be improved. In particular, when an image is formed by scanning the heat-discharge type print head 3, the heat-discharge type print head 3 and the high-voltage substrate 18a can be moved together, so that there is no load on the electric wiring. It is possible to reduce the occurrence of poor conduction that is difficult to apply.

(10) The high-voltage board 18a can be handled integrally with the heat-discharge type print head 3, and since it is not necessary to handle the electrical wiring, it can be easily incorporated into the display device 1 and has excellent mass productivity.

(11) The display medium 5 can be blanked by the restoring unit 4 of the printing unit 2, and preprocessing when rewriting the display contents of the display medium 5 is easy and practical.

(12) By making the ground electrode part 7 on the back side of the display medium 5 on which the image is written transparent, the ground electrode part 7 side can be the front side of the display screen, so the print part 2 on the writing side is externally connected. It can be hidden inside the display device 1 so that it cannot be seen, and has excellent functionality and practicality.

(13) Since the display medium 5 is fixed and the heat-discharge type print head 3 is moved and the image is written on the display medium 5, only the display medium 5 having the size of the display screen is required, and the entire display device 1 is also downsized. It is excellent in productivity and space saving.

(14) When the substrate body 6b of the display medium 5 has a liquid crystal shutter function and the ground electrode portion 7 is transparent, the transmitted light can be used with the light source portion 24a included in the display device 1 as a backlight.

(15) When the substrate body 6b of the display medium 5 has a liquid crystal shutter function and the ground electrode portion 7 is transparent, the display medium 5 includes a color filter 6c having at least three primary colors (R, G, B) in the additive color mixing method. As a result, the display screen can be colorized by an additive color mixing method using transmitted light.

(16) —When the color filter 6c is used, in which one pixel is divided into three and the display primaries are arranged in a striped pattern, the display color (by combining each color) of the display primaries can be easily controlled and the color shift can be reduced. A high-quality display screen can be obtained.

(17) The color filter 6c has the index 8a arranged in the direction parallel to the longitudinal direction of the display primary color and the index 8b arranged in the direction orthogonal to the longitudinal direction of the display primary color, so that the calorie heat discharge type printing can be easily performed. Since the head 3 can be aligned and the color of each display primary color can be controlled precisely, the accuracy of color misregistration prevention can be improved and the reliability is excellent.

(18) When the display medium 5a that does not have the liquid crystal shutter function is used, the reflected light from the light source unit 24b can be used. (19) In the case of the display medium 5a having a liquid crystal shutter function, the display primary color is at least the three primary colors (Y, M, C) in the subtractive color mixture method, so that the subtractive color mixture using reflected light is used. The display screen can be colorized by the law.

(20) When the display medium 5b capable of monochromatic display in each divided block unit is used, monocolor display is possible in each divided block unit.

(21) When a plurality of heating / discharging print heads 3 are provided in the printing unit 2, images can be written to the display medium 5 in parallel with each heating / discharging print head 3 and the display screen is rewritten. Can be shortened.

[Embodiment 2]

A display device according to Embodiment 2 of the present invention will be described below with reference to the drawings.

FIG. 14 (a) is a schematic cross-sectional view of the relevant part showing the display device in the second embodiment.

In FIG. 14 (a), the display device lb in the second embodiment of the present invention is different from the first embodiment in that the printing unit 2 is outside the display medium 5c formed in an endless loop and is opposite to the display screen side. The display medium 5c is wound around the rollers 25a and 25b of the display medium transport means and is pivotally arranged! It is.

In addition, a roller driving portion (not shown) of a display medium conveying means for rotating the rollers 25a and 25b is connected to either one of the rollers 25a and 25b.

[0077] The printing unit 2 is formed while the display medium 5c is moved by the rollers 25a and 25b of the display medium transporting means to move the display medium 5c and fixed to face the substrate surface 6a of the medium substrate 6. The displayed image can be moved and displayed on the display screen side.

By placing the display medium 5c in an endless loop shape, the ground electrode 7b is placed inside the ring of the display medium 5c (the side located behind the display screen), so that the medium substrate 6 side is the display screen side of the display device lb. The ground electrode portion 7b may be opaque because it is a (viewed by human).

If the ground electrode portion 7b is opaque, light is not transmitted. Therefore, the light source portion 24a is installed on the display screen side of the display medium 4 (the front side of the display device lb), and incident light from the light source portion 24a is transmitted to the medium substrate 4 Reflect the light with a and illuminate the display screen with the reflected light.

Next, details of the display medium will be described.

FIG. 14B is a schematic exploded view of the main part showing the configuration of one pixel of the display medium of the display device in the second embodiment.

In FIG. 14 (b), the display medium 5c of the display device in the second embodiment is different from the display medium 5 of the display device in the first embodiment in that the medium substrate 6 has one pixel instead of the color filter 6c. Is a reflection layer 6d in which the three primary colors (Y, M, C) in the subtractive color mixture method are arranged in a striped pattern as a display primary color.

[0079] The substrate body 6b of the display medium 5c has a liquid crystal shutter function (function to pass and block light), but since the ground electrode portion 7b is opaque, it controls the passage and blocking of light in the entire display medium 5c. It is not possible. Therefore, the display screen is on the substrate surface 6a side of the same medium substrate 6 as the image writing side. In the display medium 5c, since the liquid crystal shirt function of the substrate body 6b can be utilized, the color of the entire display medium 5c is displayed using the reflected light of the medium substrate 6.

Light incident on the medium substrate 6 from the light source unit 24a is reflected inside the substrate body 6b when the shutter of the substrate body 6b is closed and displays white, and when the shutter is opened, the substrate body 6b is opened. The color of the reflected light reflected by the reflective layer 6d at the back of the is displayed. Since the medium substrate 6 includes the reflective layer (background color) 6d having the colors of the three primary colors in units of pixels, a desired color using the reflected light from the light source unit 24a can be displayed in units of pixels.

The display primary colors must be at least the three primary colors in the subtractive color mixing method, but black or the like may be included as necessary. Of course, if the four colors are used, the pixels on the medium substrate 6 are divided into four to correspond to the reflective layers of the four display primary colors.

[0080] As described above, the display device according to the second embodiment has the following effects in comparison with the first embodiment.

(1) By arranging the display medium 5c into an endless loop, the ground electrode 7b side is placed inside the ring of the display medium 5c (the side that is located behind the display screen) and the outside of the ring of the display medium 5c (The surface exposed on the display screen side during image display) can be written to the display medium 5c. Therefore, the transparency of the ground electrode portion 7b is not necessarily required. The width can be expanded, and design flexibility and productivity are excellent.

(2) Since the media substrate 6 includes the reflective layer 6d in which one pixel is divided into three and the three primary colors (Y, M, C) in the subtractive color mixing method are arranged as a display primary color in a striped pattern, the reflected light is reflected. The display screen can be colorized by the subtractive color mixture method used.

(3) An area where a new image (switching image) is formed in the display medium 5c, while the display medium 5c can be moved by the rollers 25a and 25b of the display medium transport means. Can be moved to the display screen to display an image.

[0081] (Embodiment 3)

A display device according to Embodiment 3 of the present invention will be described below with reference to the drawings.

FIG. 15 is a schematic cross-sectional view showing a main part of the display device in the third embodiment. In FIG. 15, the display device lc in the third embodiment of the present invention is different from the second embodiment in that the printing unit 2 and the light source unit 24a are fixed inside the ring of the display medium 5 formed in an endless loop shape. And the medium substrate 6 side of the display medium 5 is disposed inside the ring, and the ground electrode portion 7 side is disposed outside the ring.

Note that the configuration of the display medium 5 is the same as that of the first embodiment and is as shown in FIG.

Since the ground electrode part 7 is transparent and the medium substrate 6 also has a liquid crystal shutter function, the light source part 24a is installed inside the ring of the endless loop-shaped display medium 5c together with the printing part 2, and transmitted light from the light source part 24a Just illuminate the display screen.

As described above, the display device in the third embodiment has the following operation in addition to the first or second embodiment.

(1) Since the printing unit 2 and the light source unit 24a can be installed inside the ring of the endless loop-shaped display medium 5c, the display device lc can be made compact, and the display device lc can be easily handled without irregularities. Excellent installation flexibility.

[0083] (Embodiment 4)

A display device according to Embodiment 4 of the present invention will be described below with reference to the drawings. FIG. 16 is a schematic cross-sectional view of a main part showing the display device in the fourth embodiment.

In FIG. 16, the display device Id in the fourth embodiment of the present invention is different from the second embodiment in that the printing unit 2 is rotated with respect to the display medium 5c by the printing unit moving means (not shown). It is the point arrange | positioned. Reference numeral 26 denotes a control unit of the display device Id.

Since the configuration of the display medium 5c is the same as that of the second embodiment and is as shown in FIG. 14 (b), the detailed description is omitted.

[0084] Since the printing unit 2 is movable with respect to the display medium 5c, the control unit 26 moves the printing unit 2 on the back side of the display device Id while displaying an image on the display screen side of the display device Id. The image for switching to be displayed next can be written by the heat discharge type print head 3 by moving the print head.

The control unit 26 rotates the rollers 25a and 25b of the display medium transport means after the image writing by the heating / discharge type print head 3 is completed, and displays the area where the image for switching the display medium 5c is formed on the display screen side. The image can be switched.

The switching of the image can be performed by the timer of the control unit 26 or in accordance with the end of writing of the heating / discharge type print head 3. When switching images using a timer, it is possible to automatically switch images by setting an image switching interval longer than the time required for image writing by the heat-discharge type print head 3.

When the image switching is performed in accordance with the end of writing of the heat-discharge type print head 3, the image can be switched immediately at the end of the image writing, and the waiting time can be shortened.

Note that the image switching can be performed so that the entire image is switched at once after the entire switching image has been written, or each time the heating / discharge type print head 3 performs writing of one or more lines. It is also possible to change the image little by little by intermittently moving only the part where writing has been completed to the display screen side.

An image display method of the display device Id according to the fourth embodiment of the present invention configured as described above will be described.

First, in the image forming process, the image for switching is written by the heating / discharge type print head 3 while moving the printing unit 2 during the image display of the display device Id. Display media If an image has already been formed in 5c, the image for switching is written after initialization by the decompressor 4.

When the printing unit 2 is moved in the direction of the arrow shown by the broken line in FIG. 16, it is possible to write the image for switching by the heating / discharge type print head 3 following the initialization by the restoring device 4. The printing unit 2 can be moved in the direction opposite to the direction of the arrow shown by the broken line. At that time, the image can be written by the heating / discharge type print head 3 and the initialization by the restoring unit 4 can be performed.

Next, in the image switching step, one of the rollers 25a and 25b is rotated by a roller drive unit (not shown) of the display medium transport means, and the display medium 5c is conveyed in the direction of the arrow indicated by the solid line. Then, the image being displayed on the display device Id and the switching image formed in the previous image forming process are switched.

By repeatedly performing the image forming process and the image switching process by the control unit 26, it is possible to sequentially switch the still image and display the image on the display device Id.

Next, a modification of the display device will be described.

FIG. 17 is a schematic cross-sectional view of the relevant part showing a modification of the display device in the fourth embodiment. In FIG. 17, the display device le according to the fourth embodiment of the present invention is different from the fourth embodiment in that the printing unit 2 and the light source unit 24a are fixed inside the ring of the display medium 5 formed in an endless loop shape. And the medium substrate 6 side of the display medium 5 is disposed inside the ring, and the ground electrode portion 7 side is disposed outside the ring.

Further, since the image display method of the display device le is the same as that of the fourth embodiment, detailed description thereof is omitted.

The control unit 26 can also be disposed inside the ring of the display medium 5 together with the printing unit 2 and the light source unit 24a, so that the display device le can be made compact.

[0087] When the heat-discharge type print head 3 or the restoring device 4 has a width that can correspond to the widths of the display media 5 and 5c, the direction of the arrow that moves the print unit 2 relative to the display media 5 and 5c. Images can be written on the display media 5 and 5c only by scanning. Display device Id If the width of the heating / discharge type print head 3 or restorer 4 is narrower than the width of the display media 5, 5c when the display screen of, le is enlarged, etc., it is serialized to the print unit 2 by the print unit moving means. By performing the scribing, it is possible to rewrite the image over the entire width of the display media 5 and 5c.

In the display device Id, le that uses an image display method for switching still images by repeatedly performing the image forming process and the image switching process, it is sufficient if writing of the image for switching is completed before the image is switched. Therefore, there is no problem with waiting time even if an image is formed while performing serial scanning with a small heating discharge print head 3. The heat-discharge type print head 3 can be downsized and has excellent mass productivity.

As described above, the display device according to the fourth embodiment has the following operation in addition to the second or third embodiment.

(1) By moving the heat-discharge type print head 3 and the restoring device 4 by the printing unit moving means, it is possible to perform image writing and restoration processing on the stopped display media 5 and 5c.

(2) While the image of the display device Id, le is being displayed, the switching image can be written to the display media 5 and 5c in a portion hidden from the display screen side (the front side of the display device Id, le). When the images are switched, the endless loop-shaped display media 5, 5c are simply moved by the rollers 25a, 25b of the display medium transport means, and the still image can be quickly switched like a picture-story show.

(3) The control unit 26 can automatically repeat the image writing and restoration processing by the printing unit 2 and the conveyance of the display media 5 and 5c by the rollers 25a and 25b, and the display screen can be displayed regularly or irregularly. The image to be displayed can be switched.

As described above, according to the image display method of the display device in the fourth embodiment, the following operations are provided.

(1) The display device Id, le has an image forming process for writing a switching image to the display medium 5, 5c during image display. It is possible to write an image on.

(2) Since the display device Id, le formed on the display medium 5, 5c has an image switching step for switching between the image being displayed and the switching image, the cut formed in the previous image forming step It is possible to switch the image by moving the replacement image to the display screen side of the display device Id, le.

(3) By repeating the image forming process and the display medium moving process, it is possible to switch still images in sequence, which saves power and switches still images even if the display devices Id and le are large screens. If it is used instead of a movie signboard, a still image of a typical scene can be rewritten and displayed periodically or irregularly. Industrial applicability

The present invention can provide both a large display screen and a high-definition display screen, and is excellent in practicality and visibility. In addition, when a still image is displayed, it does not require energization, and provides a display device that is excellent in energy saving. In addition, it is possible to provide an image display method of a display device with excellent functionality that can reduce the time required for switching the display screen, and it can be suitably used as an advertisement display medium.

Claims

The scope of the claims

[I] (a) a discharge part having a discharge electrode and a heating means having a heat generating part for heating the discharge electrode, and controlling the temperature of each discharge electrode to which a discharge control voltage is applied And (b) a display medium on which a visible image appears by discharge from the heating / discharge type print head. Display device.

[2] The display device according to [1], wherein the printing unit includes a restorer that initializes display content of the display medium and performs a restoration process.

3. The display medium according to claim 1, wherein the display medium includes a ground electrode portion or a positive voltage application portion disposed on a surface opposite to the surface facing the heating / discharge type print head. The display device described in 1.

[4] The display device according to any one of [1] to [3], further comprising a light source unit disposed on either the front side or the back side of the display medium.

5. The display device according to any one of claims 1 to 4, wherein the display primary color of the display medium is at least three primary colors (R, G, B) in an additive color mixing method.

6. The display device according to any one of claims 1 to 4, wherein a display primary color of the display medium is at least three primary colors (Y, M, C) in a subtractive color mixture method.

7. The display device according to claim 5, wherein each color of the display primary colors is arranged in a striped pattern on the display medium.

[8] The claim, wherein the display medium includes an indicator arranged in at least one of a direction parallel to or orthogonal to a longitudinal direction of the display primary colors arranged in a striped pattern. The display device according to 7.

[9] The display device according to any one of [1] to [4], wherein monochromatic display is performed on the entire surface of the display medium or in units of blocks obtained by dividing the display medium.

10. The apparatus according to any one of claims 1 to 9, further comprising at least one of a printing unit moving unit that moves the printing unit and a display medium conveyance unit that conveys the display medium. The display device described.

[II] (a) The display medium conveying means includes at least two rollers and at least one of the rollers. A roller driving unit that rotates any one of the rollers, and (b) the display medium force is wound around the roller in an endless loop shape.

10. The display device according to 10.

(a) an image forming step of writing a switching image on the display medium during image display of the display device according to claim 11, and (b) a display on the display device formed on the display medium. An image display method for a display device, comprising: an image switching step of switching between an image and the switching image.