Patent Application
20060124897
1. Field of the Invention
The present invention relates to an information display system comprising mobile equipment for example and an apparatus for displaying discretionary data provided by such equipment, a display device, display device drive method and display apparatus used for such an information apparatus, and specifically to a system comprising a wireless terminal for example and a noncontact IC card, a display device and its drive method using a cholesteric liquid crystal, et cetera, capable of retaining a display even if electric power (NB simply “power” hereinafter unless otherwise noted) is cut off, and a display apparatus using electronic paper with such a memory property for example.
2. Description of the Related Art
There is a requirement of enlarged display for display information on a mobile phone, PDA, digital camera, et cetera. One method to address this has been to enlarge a part of the display of such a terminal. This method naturally precludes a single view of the whole image at once, requiring operations such as cumbersome scrolling. Another method is to send image information wirelessly to equipment such as a personal computer (PC), TV, et cetera, equipped with a large screen display and thereby display the image by furnishing a mobile terminal with a short range wireless communication means such as Bluetooth, infrared or a wireless LAN. Or a method for displaying by a large screen display by transmitting the image by using a wired interface connection function such as USB, IEEE1394, et cetera, in place of wireless transmission. Such enlarged display methods are not suitable for mobile equipment in mobile environments such as away from the office or home, since they require either an AC power supply or some kind of battery, and such apparatuses per se are heavy.
There is a concept of connecting a light weight, low power consumption enlarged display to a mobile terminal as a display method in a mobile environment while avoiding the above described inconveniences. Such attempts have been made by using lightweight low power electronic paper. Such a method, however, is disadvantageous since it is an electrical contact connection. In summary: 1) a continuous connection makes the actual size of a mobile terminal large; 2) use of a connection brings about degradation due to a fatigue of the electric contact; or 3) display loss after disconnection, or possibly equipping a battery for preventing a display loss. Equipping the display unit with a battery not only causes the inconvenience of changing the battery for the display unit or charging the battery, but also an increase in the thickness and/or weight of the display. Accordingly a mobile display system whose terminal itself is substantially small, which has an enlarged screen display, and which allows hands free operation, while solving the problems as described above is required.
In the meantime, there is a requirement for printing out discretionary display information carried by a mobile phone, PDA, digital camera, et cetera, away from home, the office, or in a the location of a visit. Battery operation mobile printer apparatuses are commercially available for meeting such a requirement, which are faced with problems such as the weight and size of such equipment as well as supply of paper or batteries, however. The expectation is to have a display a la paper print without using a printer in a state of detachment from a mobile terminal.
There are conventional techniques using a contact type IC card or an RF (radio frequency) tag, and reference documents concerned with a noncontact IC card, which utilizes short-range wireless communication as follows. A patent document 1 has disclosed an IC card capable of rewriting the display content of a display.
Each of the patent documents 2, 3 and 4 has disclosed an IC card having an electric power supply for display, with a solar battery in the patent document 2, a lithium battery in the patent document 3 and an auxiliary power supply such as solar battery in the patent document 4.
The patent documents 5 and 6 deals with a memory capable display device which retains a displaying content even after the power is cut off, hence there is no need of an auxiliary power supply such as a solar battery. The patent document 5 deals with a ferroelectric liquid crystal display (“LCD” hereinafter) device and electro-chromic display device for example, while the patent document 6 proposes a use of a cholesteric-nematic phase transition type liquid crystal (“LC” hereinafter).
[Patent document 1] Japanese utility model publication H07-30384: “IC card”
[Patent document 2] Japanese laid-open patent application publication No. S62-242592: “IC card”
[Patent document 3] Japanese laid-open patent application publication No. S63-3393: “Card processing system with display function”
[Patent document 4] Japanese laid-open patent application publication No. 2003-6590: “Information storage medium with auxiliary power supply”
[Patent document 5] Japanese laid-open patent application publication No. H10-93484: “Data carrier”
[Patent document 6] Japanese laid-open patent application publication No. 2000-113137: “Noncontact information storage display method and noncontact information storage display medium”
These kinds of short range wireless generally exchange information wirelessly with a non-powered IC card by way of an IC card reader/writer equipped with a stationary terminal. It is fundamentally possible to record or display by providing a displaying/recording unit power and display information if a card and a writer are mutually in proximity. However, there has conventionally been no well designed convenient display system linking to a mobile terminal by using a noncontact wireless technique which has actually been retarded for technical reasons, e.g., shortage of power required for recording voltage, memory retention capability and recording speed for example, hence failing to accomplish a display on a noncontact mobile terminal to date. Accordingly, what have been desired are a convenient display system and an electronic paper which are suitable for mobile usage as an enlarged display by transmitting discretionary display information from a mobile terminal by utilization of a noncontact wireless technique.
Electrophoresis, while being seen as a powerful memory capable medium, its memory holding capability fundamentally contradicts high-speed drivability and low voltage drivability because the technique consists of attracting white or black electro-statically charged particulates from among those suspended in a white liquid contained by a capsule. Therefore, it is very difficult to use the technique for non-powered recording. Electrochromic memory is a memory storage method utilizing a chemical reaction and requiring a large amount of power for recording, and hence is difficult to use in wireless recording. Meanwhile, with regards to a memory capable LC, a ferroelectric memory liquid crystal medium, while rendering high-speed recording, is faced with the problems of inadequate brightness in a reflective white display due to the use of polarization film and loss of display due to physical shock.
As a memory capable LC, there is a cholesteric-nematic phase transition type LC device which has been proposed by the above noted patent document 6. This material, utilizing light scattering, has been faced with the problems of being limited to low contrast and requiring a bias voltage for holding a display stable.
In comparison to the above, a cholesteric LC (including a chiral-nematic LC), having a selective reflectivity, i.e., reflecting light of a certain wavelength selectively, reflects an optical wavelength according to the layer pitch of a liquid crystal, thereby indicating a monochromatic color. Accordingly, a layered structure has been proposed, as with a below noted patent document 7, to make it polychromatic.
[Patent document 7] Japanese laid-open patent application publication No. H09-160066: “Reflective liquid crystal display device”
In other words, the cholesteric LC indicates a certain monochromatic color and, if two LCs are combined, the desired color cannot be reflected because the colors are mixed easily. A mixture of two or more LCs makes an intermediary color or a state of no reflectance. There is a capsule structure for sealing an LC within a capsule as a method for separating LCs, which has been faced with the problems of reduced contrast due to optical noise and an increased drive voltage, both influenced by the interface and thickness of the capsule, hence its use is disadvantageous in a display apparatus, and the difficulty in laying desired capsules for desired pixels.
Let us then describe problems associated with the power supply circuit, et cetera, in the case of using such a cholesteric LC for a non-powered display apparatus such as a noncontact type IC card and electronic paper. In a common non-powered noncontact IC card, et cetera, a method used is to display by receiving power therefor along with data from a mobile terminal, IC card reader/writer, et cetera for example, by way of short range wireless, and therefore the power value usable for a power supply is small, hence requiring current regulation, et cetera, for the power supply circuit.
In particular, the cholesteric LC requires two types of drive wave forms with different peak values for driving two stable states respectively, i.e., the planar state and the focal conic state, as described later. Moreover, a drive voltage of approximately 40 volts is required to for the planar state, which is substantially higher than other display devices. Consequently high cost of the power supply circuit has been an issue. Furthermore, the use of a common DC-DC converter requires a large capacitance capacitor (in the order of micro Farads), resulting in bringing forth a problem of extreme difficulty in designing the power supply circuit within a thickness of one millimeter.
Next, electric power supplied when driving a noncontact IC card for example only by the power supplied from an IC card reader/writer varies a great deal with the distance between the reader/writer and IC card. This has brought forth a problem of shortening the communicable distance as compared to common noncontact IC cards without a display unit or temporary shortage of power required for the noncontact IC card chip during communication if the display unit is continuously operated, resulting in unstable operation. A display control in accordance with power supply is required for concerned with such a problem.
Meanwhile, the required power for driving a passive matrix type cholesteric LC is relatively small except for when starting up, making it possible to drive it adequately by the power supplied from a noncontact IC card reader/writer, with a low power output, equipped with a PDA, et cetera. However, an existing driver LSI designed for a display of moving pictures has a low impedance transistor on the last stage and therefore a start-up transition state will see an extremely large in-rush current (e.g., five to ten times the steady state). This has lead to the problem of existing drivers being unable to start up even with a supply of power several times that of the steady state.
Preparing a large capacity power supply just for startup is exceptionally disadvantageous in terms of cost, and besides it is truly impossible to supply power five to ten times the steady state by using a reader/writer with a low power output, equipped with a PDA, et cetera. This makes development of a control method for starting an existing driver LSI stably with a supply power close to the power consumption at the steady state vital.
Furthermore, the cholesteric LC requires two kinds of drive waveforms with different peak values corresponding to the planar drive and focal conic drive, respectively, as described above, additionally the peak values are required to be changed with temperature. This has then created the problem of a peak value for the planar drive at high temperatures and that for the focal conic drive at low temperatures becoming too close to secure a margin for the peak value when a larger temperature range of operation is tried. A method for securing a margin for the peak value over a wide operating temperature range is desired in order to widen the usable range of the cholesteric LC.
The next description is of problems of the cholesteric LC associated with a high-speed drive. As described above, there are two ways of driving the cholesteric LC, that is, planar drive and focal conic drive, using an AC pulse voltage in general, in which writing at higher speed than about a cycle of 20 ms, that is, 20 ms/line, causes an inadequate transition to the focal conic state as shown by
Drive methods have been developed as described below for a high speed drive method attempting to solve the above described problems, such methods, however, have been faced with various problems in application to a wireless drive using a low power electromagnetic wave, such as a noncontact IC card, which the present invention aims at. The following lists representative high speed drive methods and the related problems assuming the use of a cholesteric LC:
The patent document 8 listed below has disclosed a writing method called the FCR (focal conic reset) method which first applies a reset voltage to all scanning electrodes for a transition to the focal conic state, followed by applying a selection voltage sequentially by one scanning electrode at a time. A bulk reset by selecting all the scanning electrodes, however, requires very large power consumption due to selecting all the scanning electrodes, and hence is not suitable to a wireless drive. The power consumption is particularly large for transition to the focal conic state.
The patent document 9 also uses a method of full-line homeotropic reset, requiring very large power consumption as with the above and precluding use for a wireless drive.
A DDS (dynamic drive scheme) method disclosed by the patent document 10, et cetera, while giving a high speed scan, describes a complex drive wave form which complicates its drive circuit and hence increases cost. Furthermore, a long elapsed time before the display state of pixels settles itself (i.e., reset period to holding period) is so long as to increase the power consumption, also precluding use for a wireless drive.
Meanwhile, an MLA (multi-line access) method widely known in association with a STN drive also drives many lines in bulk, requiring large power consumption and hence is unsuitable to use for wireless drive. Furthermore a complicated drive circuit makes cost high.
An image with high spatial frequency such as a checkered pattern makes the power consumption remarkably large, hence drive methods as described above are all the more unsuitable to a wireless drive.
A planar reset leaves a residual image.
The patent document 11 has disclosed a method for detecting a plurality of lines including the data the same as writing line data, for example, and writing the plurality of lines simultaneously, but a method for determining the maximum number of lines to be written simultaneously is unknown.
[Patent document 8] Japanese laid-open patent application publication No. H11-326871; “Drive method for liquid crystal display device
[Patent document 9] Japanese laid-open patent application publication No. 2002-6287; “Drive method for memory capable cholesteric liquid crystal display apparatus and its drive apparatus”
[Patent document 10] Japanese laid-open patent application publication No. 2002-55327; “Liquid crystal display apparatus and drive method for liquid crystal display device”
[Patent document 11] Japanese laid-open patent application publication No. H10-20809; “Image display method and apparatus”
When concerned with a drive associated with a noncontact IC card for example as with the present invention it does not particularly require a high speed drive of the order of microseconds, but rather requires a unique method with a high speed drive of high quality corresponding to the low power of wireless.
Last but not least in this section, let us describe a problem about a display apparatus using an electronic paper which utilizes the above described cholesteric LC, et cetera. That is, while a display apparatus using an electronic paper with a characteristic of two kinds of properties, i.e., a display will not disappear soon after cutting off the power and the display content is discretionarily rewritable, which are well integrated, has been in development, there has been the problem of such conventional apparatus not comprising the function of automatic display, however.
In other words, such display apparatus lacks the characteristic of automatic display apparatus as a result of not possessing information about when, where or how data to be displayed shall be acquired and/or information about a displaying form for the acquired display data, and therefore, an automatic display apparatus, which would acquire display data automatically based on the information about the acquisition method, or carry out a display automatically based on information about the displaying form followed by transitioning itself to a ready state automatically, has not been provided. Such has been another problem.
A first purpose of the present invention is to provide an information display system as a whole by enabling mechanical detachment between an information display apparatus without a power supply for example and a wireless terminal, which sends discretionary display data and power thereto.
The second purpose is to provide a display device capable of accomplishing a high contrast with a low cost by using a cholesteric liquid crystal in a plurality of colors and a display apparatus using such a display device.
The third purpose is to provide a power supply circuit capable of operating an IC card stably by using various control methods, even if the electric power supplied for a noncontact IC card for example is small.
The fourth purpose is to provide a device drive method, and an image display method, with the smallest possible power consumption in a display apparatus using a cholesteric liquid crystal for example.
The fifth purpose is to provide an automatic display apparatus capable of storing information relating to an acquisition method for data to be displayed and information relating to a displaying form for the display data, acquiring external data automatically, both displaying the data, and subsequently returning to a ready state automatically, and suitable to a wide range of applications.
An information display system according to the present invention comprises a display apparatus and display data retention apparatus. The display apparatus comprises a display unit capable of continuing data display even if the power is cut off, a short range communication unit for carrying out a short range communication in order to receive discretionary external data to be displayed, and a display control unit for controlling display performed by the display unit in response to received data by the short range communication unit.
The display data retention apparatus comprises a storage unit for holding display data, and a transmission unit for transmitting display data over to the display apparatus at least within a short range in response to storage content of the storage unit.
A mechanical quick release unit can be comprised for attaching the display apparatus to the display data retention apparatus detachably, and data displayed on the display data retention apparatus, such as a display in a mobile terminal, may be transmitted to the display apparatus for performing an enlarged display.
A display device according to the present invention, in the display device having two substrates, between which liquid crystal is injected, comprises partition walls with a structure for keeping plural colors of liquid crystals, which are injected between the two substrates, from touching one another.
Meanwhile, the display apparatus according to the present invention, comprises a first display device having transmission and reflection modes, and capable of switching display content, and a reflective second display device for displaying a fixed image or character and enabling the viewing of the display content through the first display device.
The display apparatus according to the present invention comprises a temperature compensation unit for changing a peak value of each drive voltage waveform corresponding to the planar and focal conic states of cholesteric liquid crystal for example responding to a temperature. The display apparatus according to the present invention has a coil furnished for receiving an external high frequency magnetic field, wherein the coil comprises an intermediary tap with one end of the coil being grounded and a for-resonance capacitor being connected between the intermediary tap and ground, a logic-use power supply unit for supplying circuits other than the one for display use with a voltage by rectifying a high frequency voltage generated across the resonating capacitor, and a display-use power supply unit for supplying a display-use voltage by rectifying a high frequency voltage generated between the other end of the coil and intermediary tap.
As a device drive method according to the present invention, in a matrix type display apparatus using a cholesteric liquid crystal, the device drive method comprises the steps of setting some scanning electrodes for reset and writing lines to a selection state and a pause line to a non-selection state, respectively; and providing a writing data signal to a signal electrode side while shifting the reset, pause and writing lines respectively.
Also as a display device drive method according to the present invention, in the above described matrix type display apparatus, the drive method comprises the steps of detecting a plurality of lines on which data patterns to be displayed are the same from among a plurality of lines on a display screen; and writing the same pattern in bulk by selecting the detected plurality of lines simultaneously and applying data of the same pattern to the signal electrodes.
A display apparatus according to the present invention comprises a display unit capable of continuing data display for example even if power is cut off; a storage unit for storing information relating to an acquisition method for data to be displayed and one relating to a displaying form for acquired display data; and a control unit for controlling acquisition of display data externally, and display of the display data in the display unit, both in accordance with the storage content of the storage unit.
As described above, according to the present invention, a display apparatus is configured by using a cholesteric liquid crystal display device, et cetera, capable of continuing data display even if the power supply is cut off for instance; and an information display system is configured by using the display apparatus, display data retention apparatus, such as a mobile terminal, for supplying the display apparatus with display data and power.
The display apparatus 1 comprises a display unit 3 capable of continuing data display even if the power is cut off for example, a short range communication unit 4 for carrying out short range communication in order to receive data to be displayed provided externally, and a display control unit 5 for controlling display performed by the display unit 3 in response to discretionary data received by the short range communication unit 4.
The display data retention apparatus 2 such as a mobile terminal comprises a storage unit 6 for holding display data, and a communication unit 7 for transmitting display data to the side of display apparatus 1 at least within a short range according to a storage content of the storage unit 6.
The display data retention apparatus 2 may further comprise a long range communication unit, being capable of long range communication unlike the communication unit 7, for acquiring display data provided externally so that the communication unit 7 transmits display data acquired by the long range communication unit to the display apparatus 1 side.
The display apparatus 1 may further comprise a mechanical quick release unit for mounting the said apparatus onto a human body or clothing.
The display data retention apparatus 2 may further comprise a display unit with a smaller display area than that of the display unit 3 comprised by the display apparatus 1 and a mechanical quick release unit for mounting the display apparatus 1 onto the said apparatus; or the display data retention apparatus 2 may further comprise the display unit itself as described above and at the same time the display apparatus 1 may further comprise a mechanical quick release unit for mounting the display data retention apparatus 2 onto the said apparatus.
Meanwhile, the short range communication unit 4 comprised by the display apparatus 1 is enabled to receive not only data to be displayed but also power for displaying and display control information, all from the display data retention apparatus 2 side.
A display device according to the present invention comprises partition walls with a structure for keeping plural colors of LCs, which are injected between two substrates, from touching one another.
A surface of the partition wall facing the substrate may be configured to possess an adhesive property, the plural colors of LCs may be cholesteric LCs, or the additive colors of the plural colors of LCs may be white.
Meanwhile, the display apparatus according to the present invention, having transmission and reflection modes, comprises a first display device capable of switching display contents, and a reflective second display device for displaying a fixed image or character and enabling viewing of display content through the first display device.
The second display device may be a printed material or a material written in characters or as an image by hand and detachably attached to the first display device, or the first display device may have the function of changing a display area corresponding to the position and shape of the fixed image or character on the detachably attached second display device.
The display apparatus according to the present invention also comprises a temperature compensation unit for respectively changing peak values of two kinds of drive voltage waveforms corresponding to the two stable states of an LC in response to a temperature.
The aforementioned LC is a cholesteric LC and the temperature compensation unit may also be configured to be capable of changing the peak value of drive wave form applicable to the focal conic state along the straight line connecting two points, i.e., the average of the upper and lower limit values of the peak value of the drive wave form at the lower temperature limit and that of the upper and lower limit values of the peak value of the drive wave form at the higher temperature limit.
The display apparatus according to the present invention has a coil furnished in order to receive an external high frequency magnetic field and comprises a display-use power supply unit for supplying a display-use voltage by rectifying a high frequency voltage induced by the coil, and a logic-use power supply unit for supplying circuits other than the one for display use with a voltage by rectifying a high frequency voltage induced by the coil.
In this case, the coil may comprise an intermediary tap with one end of the coil being grounded, a for-resonance capacitor may be connected between the intermediary tap and ground, the logic-use power supply unit may rectify a voltage across the for-resonance capacitor, and the display-use power supply unit may rectify a voltage across the other end of the coil and intermediary tap.
The display apparatus also comprises a display unit for performing data display by using power supplied externally by noncontact means, and a display function control unit for controlling a display function of the display unit in response to the externally supplied electric power.
The display apparatus also comprises a display-use power supply which uses a part of the power supplied externally without a contact, and a logic-use power supply for supplying circuits other than the display unit with power by using a part of the power supplied externally without a contact, and a current regulation unit for regulating an output current of the display-use power supply in response to a voltage drop of the logic-use power supply.
In the meantime, a display device drive method according to the present invention, for use in a matrix type display apparatus using a cholesteric liquid crystal, comprises the steps of setting some scanning electrodes for a reset and writing lines in a selection state and for a pause line in a non-selection state, respectively; and applying a writing data signal to a signal electrode side while shifting the reset, pause and writing lines, respectively.
In this case, a writing alternate signal applied to a reset and writing lines may reverse polarities within a time corresponding to one line and also have a period corresponding to two lines.
Next, the display device drive method according to the present invention, for use in the matrix type display apparatus, also comprises the steps of detecting a plurality of lines, on which data patterns to be displayed are the same, from among a plurality of lines on a display screen; and selecting the detected plurality of lines simultaneously and writing the same pattern data in bulk by applying data of the same pattern to signal electrodes, in which the maximum number of the plurality of lines on which a writing in bulk is carried out may be inversely proportional to the spatial frequency of the same pattern data.
Furthermore, the display device drive method according to the present invention comprises the steps of converting image data to be written in an LC device into image data having n-number of gray scales; extracting a pixel of each gray scale level after conversion; and forming, for the extracted pixels: a sub-image 1 which is formed by converting the pixels on the least bright gray scale level 1 (i.e., on the black level) and n-th least bright gray scale level n (i.e., on the white level) into black and white levels, respectively, a sub-image 2 which is formed by converting the ones between the least bright gray scale level 1 and the second least bright gray scale level 2 into a black level followed by combining with the gray scale level n, and so on and so forth . . . , and a sub-image (n−1) which is formed by converting the ones between the least bright gray scale level 1 and (n−1)-th least bright gray scale level (n−1) into a black level followed by combination with the gray scale level n, in which a display of the n-number of gray scales is obtained by starting writing the sub-image 1, followed by the sub-image 2, and so on and so forth, and sub-image (n−1) in that order. Also, the display device drive method comprises the steps of converting image data to be written in an LC device into image data having n-number of gray scales; extracting a pixel of each gray scale level after conversion; and forming, for the extracted pixels: a sub-image 1 which is formed by converting the pixels on the brightest gray scale level 1 and n-th least bright gray scale level n into a white and black levels, respectively,
a sub-image 2 which is formed by converting the ones between the brightest gray scale level 1 and the second brightest gray scale level 2 into a white level followed by combining with the gray scale level n, and so on and so forth . . . , and a sub-image (n−1) which is formed by converting the ones between the brightest gray scale level 1 and (n−1)-th brightest gray scale levels (n−1) into a white level followed by combining with the gray scale level n, in which display of the n-number of gray scales is obtained by starting writing the sub-image 1, followed by the sub-image 2, and so on and so forth, and sub-image (n−1) in that order.
In the display apparatus 10 shown by
Also, the display apparatus may further comprise a data acquisition unit for acquiring yet-to-be acquired display data at a communication restart if a communication is interrupted in the middle of acquiring display data provided externally, an overwriting inhibit unit for inhibiting overwriting of data displayed by the display unit 11, and a nonvolatile storage unit for storing data for no less than one page of displaying by the display unit 11.
Preferred embodiments of the present invention will now be described by categorizing them into some embodiments in the following. To begin with, the description will deal with a first embodiment, that is, an information display system for carrying out display on the display apparatus side by using power transmitted from a wireless terminal side, such as a noncontact IC card, along with data, while an information display apparatus, that is, a display panel has no power.
The wireless terminal 20 comprises a power supply unit 25, a control unit 26, an antenna 27 for performing short range communication with the wireless display panel 21 side, a noncontact transmission/reception unit 28 for controlling communication by using the antenna 27, a memory unit 29 for storing display data, et cetera, to be transmitted to the wireless display panel 21, a display unit drive circuit 30 for controlling a data display over at the wireless terminal 20, a display unit 31 and a speaker 32.
The wireless display panel 21 comprises an antenna 36 for short range communication with the wireless terminal 20, a transmission/reception unit 37 for carrying out the aforementioned communication, a control unit 35 for controlling the whole, a memory unit 38 for storing for-display data and for-control data, a display unit drive circuit 39 for performing data display, memory capable display unit 40, and a mechanical mounting mechanism 41 for enabling the wireless terminal 20 to be detachably attached to the wireless display panel 21.
The wireless terminal 20, such as a mobile phone, is usually furnished with a small display. Use of the wireless display panel 21 as a non-powered display card is for enlarging the screen display and displaying the whole image in a larger screen, while a comprisal of the mechanical mounting mechanism 41 as a mechanical quickly detachable attachment unit for mounting the wireless display panel 21 onto a mobile phone makes it possible to integrate it with the mobile phone. In configuring this, installed nearby the mechanical mounting mechanism 41 is the transmission/reception unit 37 used for short range communication whose system has the functions of supplying power for a display at the wireless display panel 21 as well as communication of the display data. This function enables a short-range wireless communication function such as an IC card or RF (radio frequency) tag for example.
The memory capable display unit 40 can take advantage of a device which for instance retains the display state semi-permanently even after the power supply is cut off, such as a later described cholesteric LC, or alternatively a display media capable of retaining the display state for a certain period of time if not for semi-permanently, or a display unit in association with a commonly used buffer memory and its memory content.
For example, mounting a display card on an arm, listening to a voice by holding a mobile phone close to an ear and bringing the arm close to the mobile phone make it possible to have a phone conversation while looking at the screen display on the card. By this method it is possible to take advantage of a large screen display of lightweight and compact size, et cetera, without any need of a battery due to non-powered card. Furthermore, it is possible to leave a mobile phone in a breast pocket and bring a display card close to the chest to have the display card detected and thereby carry out data transmission and the resultant screen display.
Note here that the display of a still image is preferred for the one on the wireless display panel 21, that is, the non-powered display card. The reasons are that a device capable of continuing the display after the power is cut off for example has a property of low writing speed to begin with, that a large display screen is often used for a still image, taking advantage of its large information capacity, and that displaying moving images on a screen with a large information capacity requires very large power consumption. Moreover, generally speaking, transmission of a display to a non-powered display card should preferably be conducted intermittently in order to minimize the power consumption. For example, transmission and display of data in 50 ms followed by a pause of 100 sec greatly saves display power.
Note also here that in claims of the present invention, a display unit corresponds to the memory capable display unit 40, a short range communication unit corresponds to the antenna 36 and transmission/reception unit 37, a display control unit corresponds to the control unit 35 and display unit drive circuit 39, a storage unit corresponds to the memory unit 29, and a communication unit corresponds to the antenna 27 and non-contact transmission/reception unit 28, all of the above relating to claim 1, with all the aforementioned numbered components being listed by
In the claim 2, a long-range communication unit corresponds to the external wireless transmission/reception unit 23. In the claim 3, a mechanical detachable attachment unit corresponds to the mechanical mounting mechanism 41; and in the claim 4, a display unit corresponds to the display unit 31, with all the numbered components above being listed by
As described so far, the first embodiment enables the displaying of a screen furnished with mobile equipment by a large screen or multi-screens in hands-free and also the use of display results of the remaining display through the utilization of a memory function even after detaching the large screen from the mobile equipment by mounting a non-powered large screen display, which is usually separated from a mobile equipment, et cetera, integrally with a mobile terminal or a mobile equipment such as a digital camera at the time of usage.
Specifically, the use of a cholesteric LCD device allows acquisition of a low cost and easy-to-make film based, passively driven, high resolution, memory capable color display. It is possible to accomplish not only the same resultant effect as printing by a mobile printer without ever using one, but also a color display or large screen display which is hardly achievable by a mobile printer. Especially for a terminal required to be of compact design such as a mobile phone, the actual effect of a large screen display is substantial.
It is also possible to obtain reference materials, catalog information, et cetera, by using the wireless communication function comprised by a mobile terminal to store it as a display record for a large screen display. Holding a display panel with a memory capable display function in a pocket or brief case enables instantaneous easy viewing of a large screen. Also, mounting a non-powered display card onto a person makes it possible to solve the conventional shortcomings of weight, bulkiness and need to recharge, et cetera, caused by a wearable display using a battery.
What follows here is the description of a cholesteric LCD device as a representative display medium capable of continuing display in a state of the power supply being cut off and a display apparatus using the display device as a second embodiment of the present invention.
First, let a characteristic of the cholesteric LC be described in general terms. The cholesteric LC has a property of reflecting light in a certain wavelength range selectively; among such materials chiral-nematic LC is the result of nematic LC forming a cholesteric phase by adding a chiral material thereto. The cholesteric LC provides two stable states, i.e., the planar state as a reflective state and the focal conic state as a transmissive state, by electrical control, having the characteristic of memory property in holding the planar and focal conic states, respectively, semi-permanently unless a certain kind of external force is applied.
λ=n*p
The reflectance band Δλ increases with a refraction index anisotropy Δn of the LC.
In
In
The next description is of a comprisal of a display device using cholesteric LC. A cholesteric LC basically indicates a monochrome color of a certain color tone and, if two LCs mix, they end up mingling easily, resulting in an inability to reflect a desired color tone. That is, a mixture of two or more LCs makes either an intermediary color or a non-reflective state. Therefore, it is necessary to set up partition walls in a pair of facing matrix substrates so as to make a structure isolating adjacent pixels or in the unit of dots in order to keep a plurality of LCs from mixing with one another and inject the respective LCs from different inlets.
Although a capsule structure, to contain an LC in a capsule is being used as a method for separating LCs, the influences of the borders between capsules and thickness thereof bring forth a reduced contrast by optical noise and an increase in drive voltage, making them disadvantageous for a display apparatus. It is also very difficult to place desired capsules in desired pixels, whereas it is possible to accomplish a high contrast at a low cost by adopting a separation structure using partition walls as in the second embodiment.
Accordingly as shown by
Furthermore in
The next description is of a display apparatus combining a display device using a cholesteric LC with a printed media using paper and/or a photograph. As described before, a cholesteric LC has two stable states, i.e., a planar state as a selective reflective state and a focal conic state as a substantially transparent state. A common display type has provided a bright display in the reflective state and a dark display in the transmissive state by placing a light absorption layer (i.e., black layer) under the LC element.
The cholesteric LC, however, allows a transparent state, that is, vision of a background in the focal conic state if a light absorption layer is not placed thereunder. Accordingly, utilization of the transparent state in the focal conic state and integration with a printed medium, e.g., generally a paper medium, enables a provision of an LCD apparatus capable of a wide application.
There have been proposals for restaurant menus, et cetera, as application examples for an electronic paper capable of a semi-permanent display, but where there is no need to change the display of the entire menu area. An image of merchandize for example can usually be a fixed display, while it is desirable to use a photograph for improving the image. The accompanying price and advertisement of “today's special” for example should preferably be a variable display. Accordingly, the second embodiment is configured to accomplish an overlapping display form as a whole by combining an electronic paper media, such as a display device using a cholesteric LC, with a printed medium such as a photograph. An image of merchandize as printed material has a high degree of reality, while the price or advertisement content of today's special can be changed by using electronic paper, thus enabling an integration of paper and electronic paper.
It is possible to accomplish a display suitable to the display content of the printed material by adopting for example a matrix display type for the electronic paper, which uses a cholesteric LC. Diverse application forms can be conceived by making printed materials as templates. For example, a use of a calendar as a printed material accomplishes a variable schedule chart by an overlapping display of the electronic paper with the calendar.
The LCD displays color in accordance with its layer pitch. This sometimes causes a reduced visibility of the printed material laid underneath, depending on the color thereof, requiring a consideration of the area for carrying out a variable display. Black is preferred for the area of printed material in order to improve the visibility by increased contrast. Also, the use of gray for reducing reflections will enable better visibility. Alternatively, coloring the area for changing the reflected light 78 to a specific color will make an additive color with the display device reflected light 79, thereby enabling a change of color. For example, setting the reflected light 79 of a display device to orange and the color of printed material to blue will make the displayed color white. Through various refinements of printed material, various colors can be given to each area. White is the most favored color. Setting the colors of printed material and reflected light of the display device with the relation of complementary colors with each other accomplishes a white display. Orange and blue are complementary.
As described so far, the second embodiment enables accomplishment of multi-color display by injecting a plurality of color LCs in a matrix display device using a cholesteric LC. The use of simplified components having a reduced number of border surfaces and a high contrast makes it possible to accomplish a cost reduction.
Also, the combination of a cholesteric LC matrix display device, as a variable display device, with a printed material, as a fixed display device, integrates an electronic paper with paper, making it possible to bring out the characteristics of the electronic paper and paper to the largest extent. Making printed material as a template and only replacing content thereof with new content by detaching from, and attaching to, the variable display device enables the development of various applications. A database storing the templates for printing materials enables layout change, content change and update of the display device instantly. The variable display device is durable enough for many times of use, hence reducing cost. The fixed display device may be hand-written, in place of printed material, and an overlapping display is also possible by placing a cholesteric liquid crystal display device on a picture painted on a wall of building.
The next description is of a third embodiment. In using a non-powered display card as described in the first embodiment for accomplishing a semi-permanent data display for example in the present embodiment, various control methods are required for a power supply circuit since electric power supplied from a noncontact IC card reader/writer for example is small. Such a control for the power supply circuit is described as the third embodiment.
As described in relation to
Accordingly, the third embodiment is configured to use a power supply circuit for generating a high voltage of about 40 volts by an ultra-thin circuit through utilizing a high frequency magnetic field used to supply a signal and power for a noncontact IC card or RF tag, instead of using a DC/DC converter.
The configuration shown by
Next, a passive matrix drive circuit for example requires the application of voltages to LC cells on the selected level scanning line for the planar and focal conic drives, respectively, while a voltage to LC cells on the unselected level scanning line so as to keep a state of writing at selection independent of the segment line level. That is, the applied voltage is to suppress a common cross talk, thus requiring five kinds of voltage values in the application of commercially available STN LCD driver LSI for example.
Next, when using a noncontact IC card for example as a non-powered display card, the supplied electric power from a noncontact IC card reader/writer varies greatly depending on the type thereof, the distance between the noncontact IC card reader/writer and the noncontact IC card. This may bring forth the possibility of shortening a communicable distance substantially as compared to that of a common noncontact IC card without a display unit, or the operation becoming unstable due to power shortage during communication, if the display unit on the card is operated continuously. The third embodiment accordingly limits a display function in response to supplied electric power as a countermeasure to the above-described problem.
In
The next description is of current limiting for a display-use power supply. It is possible to drive a passive matrix type cholesteric LCD panel by an existing driver LSI used for a passive matrix type STN LCD by using the above described power supply circuit. Power supplied from a noncontact IC card reader/writer having a very small output power can operate the aforementioned passive matrix type cholesteric LCD panel, except for when starting up. Such an existing driver LSI, however, assuming use for displaying a moving picture, has a transistor on the last stage with a low conductive impedance so as to allow an extremely large surge current (i.e., a magnitude of five to ten times the steady state) in a transition state at the start. Due to this, it may not be possible to start an existing driver LSI even with a current several times the steady operation state.
But, preparing a large power supply just for starting is tremendously disadvantageous in terms of cost. Besides, it is just impossible to supply electric power of the magnitude of five to ten times the steady state operation by way of an existing noncontact IC card reader/writer having a very small output power. Accordingly the third embodiment is configured to limit the current for a display-use power supply in order to start up an existing driver LSI stably by supplying power as close to the power consumption in the steady state as possible.
Meanwhile, at startup, stopping clock output until the voltage value of the display-use power supply exceeds a prescribed value by using the same circuit as
In an existing common LCD driver LSI, a display-use power supply current may sometimes exceed the average current for the steady state operation depending greatly on the display pattern, not just at the startup. An interruption of display panel drive until the display-use power supply voltage recovers to a prescribed value by regulating the current as with the startup will enable stable operation of the existing driver LSI.
The next description is of temperature compensation of the drive characteristic for the cholesteric LC according to the third embodiment. The cholesteric LC requires two drive waveforms with different peak values corresponding to the planar and focal conic states, in which the peak values further changes with temperature. Consequently, a temperature compensation for changing a peak value corresponding to temperature is necessary for widening an operating temperature range. The third embodiment is configured to secure a margin of peak values in a wide operating temperature range by changing the peak value of the drive waveform linearly with temperature.
Referring to
Compared to the above, it is known that the margin of peak values for the focal conic drive becomes wider with pulse width.
The third embodiment is basically configured to use the centerline for changing the peak value of the drive waveform in terms with respect to temperature for the focal conic state. The new margin of the peak value, required to fall between the upper and lower values for the focal conic state as shown by
In
A sensor output at a certain temperature is computed by an arithmetic circuit, not shown, and so the output values thereof at 0° C. and 50° C. are equal to the indication value of the average of the three lines for the focal conic drive described in
The TR1 and TR2 each constitute an emitter follower circuit for adequately lowering the output impedance, with each emitter voltage, that is, the output value for the planar voltage for one, and the focal conic voltage for another, are lower than the respective transistor base voltages by about 0.7 volts. Therefore, the planar voltage output value at 0° C. is about 48.6.volts (=49.3−0.7) and at 50° C. is about 33.0 volts (=33.66−0.7) which are adequately higher than the minimum value of the peak value of the drive voltage waveform for the planar state, that is, the minimum voltage, i.e., 43.3 volts at 0° C. and 30.9 volts at 50° C., for the planar state described in association with
The base voltage of TR2 is the value R4 times the output voltage of AMP1 divided by (R3+R4). The value of this coefficient is equal to 1/1.7 which is the emitter voltage of TR2, that is, the output value of the focal conic voltage being 28.3 volts (=29.0−0.7) at 0° C., and about 19.1 volts (=19.8−0.7) at 50° C. These values are represented by the three lines described in association with
While the descriptions of the third embodiment have so far been ranging from the power supply circuit, display function limit circuit, and display-use power supply current regulation circuit for a noncontact IC card, to the temperature compensation circuit for a cholesteric LC drive voltage, these circuits will actually be used in combination of some of them, rather than as individual circuits independently. Such combinations can be made possible by selecting some circuits on an as required basis.
It is also possible to determine the values of devices and reference voltages for each circuit relatively easily. While a detailed description such as the determination of resistance values has been given herein for the temperature compensation circuit shown by
As described above, the third embodiment accomplishes a substantial cost reduction and slimming of power supply circuit for a display panel using a cholesteric LC for example, avoidance of shortening a communicable distance or operational instability by limiting the display function in response to the supplied electric power and stable and quick startup of an existing driver LSI through regulating the current of a display-use power supply at startup, thereby increasing applicable ranges of mobile equipments greatly.
The subsequent description is of a fourth embodiment concerned with a drive method for an LCD device and an image display method used in a display apparatus using a semi-permanent memory capable display device such as a cholesteric LC device. In the fourth embodiment, the ensuing description deals with a drive method and image display method for carrying out an LC device drive and image display with the smallest possible power consumption in order to use a display apparatus, for which a cholesteric LC is utilized for example, in a non-powered condition.
Referring to
The matrix type LC device 84 comprises a scanning electrode for commonly selecting a line and a signal electrode for providing data, with the scanning electrode receiving a polarity reversed signal FR for the purpose of making a drive signal an alternating signal for the LC device, an Eio signal as a line selection signal, an Lp signal for the purpose of latching data over at the signal electrode and shifting a scanning line, et cetera; and with the signal electrode receiving a data signal used for writing in addition to the aforementioned FR signal and Lp signal.
The scanning electrode usually receives the Eio signal for selecting a scanning electrode for the purpose of writing data line by line from the top line, whose mode is called a common mode herein. Comparably, it is also possible to provide data to be called a segment mode for the purpose of writing data on a discretionary line in lieu of writing data line by line from the top line and also a signal for switching these two modes.
Accordingly, the fourth embodiment is configured to reset in units of several lines such as by four lines to repeat the operation of writing data for one line simultaneously with rewriting the screen, thereby suppressing the power consumption; and use rewriting data per se as the reset-use data for resetting, rather than using specific reset data such as converting all the pixels to white.
Referring to
Referring to
The subsequent pause line setup period is only inputted by an Lp signal, thereby shifting one line, thus the second through fifth lines in the screen assume the state of being selected.
In the beginning part of the subsequent writing period, Eio and Lp signals are simultaneously inputted to shift the previously selected second through fifth lines by one line respectively so that the third through sixth lines assume the state of being selected and at the same time input of an Eio signal makes the first line in the screen, that is, the first line also assumes the state of being selected. Providing data meant for the first line in this state causes the data itself to be written therein and at the same time the same data meant for the first line is provided to the third through sixth lines for resetting the previously displayed data therein. In this event, the second line is now a pause line set up by the pause line setup period so that no data will be written therein.
In response to the next Lp pulse input, the previously selected line is shifted so that the second line and the fourth through seventh lines assume the state of being selected. Providing data meant for the second line in this state causes writing therein with the data to be written therein and at the same time resets the previously displayed data in the fourth to seventh lines.
A further input of the next Lp pulse selects the third line and the fifth through eighth lines for writing data in the third line. While the data meant for the first line was written to the third line as a result of inputting an Lp pulse two pluses prior, the response time of the cholesteric LC is generally on the order of tens of milliseconds (10 s ms), with some variance due to material characteristics. At the time of inputting an Lp pulse as the timing for writing data to the second line, the third line is in a pause period so that the pixels in the second line are in the focal conic state, or in a state of transitioning to the planar state in this period (e.g., 50 ms or less) and that a decision will be made for either the focal conic state as an actual writing state or the planar state at the time of actually receiving data for the third line. Thus these operations will be repeated until data is written to the 240th line for example, that is, the bottom line of the screen.
The next description is of a different power suppression method according to the fourth embodiment while referring to
The upper part of
The next description is of a skip drive method as an image writing method according to the fourth embodiment while referring to
Referring to
Next, the scanning electrode side selects parts for writing with the same pattern, that is, a “white background” herein, and writes in bulk to electrodes in these parts. This makes it possible to write a white background pattern in a plurality of lines simultaneously, thereby enabling a shortened drive time.
The aforementioned same pattern is not specifically limited, but a pattern with a high spatial frequency, such as checkers, increases the power consumption, and therefore it is necessary to limit the number of lines to write in bulk according to the pattern. In other words, the number of lines to be selected in bulk will be reduced with the spatial frequency of the pattern.
There is a low possibility of the same pattern existing in an image if the image is of random patterns as a result of image processing by using an error diffusion method which diffuses an error of a certain pixel to the neighboring pixels, whereas there is a possibility of the same pattern existing in an image processed by a systematic dither method as one kind of a binary dither method which adds noise to a density signal of a halftone image to binarize through threshold processing, or in a halftone image using a dot pattern. The skip drive system, however, is particularly effective for an image with many white background areas such as text display.
Returning to
The flow chart on the right side of
The next description is of a multi-value writing method according to the fourth embodiment while referring to
First, let the case of three-value writing be described. The first operation is to run a screening process with three values, for example, 0, 128 and 255 for an image with a 8 bit 256-step gray scale. Although the kind of such processing is not specifically limited herein, to use of the above described error diffusion method or a blue noise mask method as image processing for a larger image area it be possible to generate a pseudo-halftone image with a high resolution.
Following the three-value screen processing, extract pixels of black (i.e., “0”) level, that is, pixels to be basically written as black, and run an initial scan for such pixels only, thereby writing a halftone image. That is, driving the LC device faster than usual carries out image writing of halftone level in a state of fixed output voltage of the driver. An adjustment of drive speed can obtain an image with halftone data being written in pixels for which black is supposed to be written as shown by
Subsequently, the second scan, that is, writing data which is converted from a black (0) level and intermediate level (128) to the black (0) level changes pixels which were a gray halftone before, as shown by
As described above, the fourth embodiment makes it possible to suppress the power consumption a great deal of driving and display a high quality image in a short time without allowing a residual image or a reduced contrast in a non-powered display apparatus using a display device which has a semi-permanent memory property such as a cholesteric LC.
The description now proceeds to a fifth embodiment. In the fifth embodiment, the description concerns a more detailed comprisal and wider range of application of the display apparatus with a semi-permanent memory property such as a cholesteric LC for example. In the fifth embodiment, an automatic display apparatus, at least comprising a display medium having a semi-permanent memory property which retains display content even if power is shut off, memory for retaining information relating to an acquisition method for data to be displayed and information relating to a display form of the acquired data, an Internet connection unit, for example, for acquiring display data based on the data acquisition method, and a control unit for displaying the acquired data according to the retained display form, acquires display data after being started in response to an instruction given externally or internally and carries out data display on a display medium with a semi-permanent memory property by adjusting a display form.
In
Note here that, in claims herein, a display unit corresponds to the memory capable display unit 40, a storage unit corresponds to the nonvolatile memory 95 and a control unit corresponds to the control unit 35 and display unit drive circuit 39, all of which are noted by claim 25. Also, in claim 30, a nonvolatile storage unit corresponds to the nonvolatile memory 95 which can store display data for a plurality of pages to rewrite the content of the memory capable display unit 40 and to restore a content which has been displayed by the memory capable display unit 40 by using the content of the nonvolatile memory 95 if the content is erased by some cause.
When the distance from the communication terminal 97 becomes a prescribed value or less, the automatic display apparatus 90 is started up to operate in the same way as in the case of
The fifth embodiment is capable of carrying out not only data display but also displaying an update date and time of data.
Further description continues for another example comprisal of the automatic display apparatus according to the fifth embodiment. First, while the memory capable display unit 40 shown by
In this case, it is possible to have a size equivalent to one page or plural pages of nonvolatile memory. In the case of a display device having a semi-permanent memory property, such buffer memory is not necessarily required, but equipping of one of page buffer memory will make it possible to restore display content instantly if a part, or the entirety, of the display content of the display device disappears due to exceeding the upper temperature limit of the memory property for example. The equipment of buffer memory for plural pages also makes it possible to switch the display contents instantly.
The automatic display apparatus is also capable of inhibiting rewriting of the data displayed by the memory capable display unit 40 shown by
Meanwhile, if a communication with an external entity is interrupted in the middle of the automatic display apparatus operating to acquire display data provided externally, it is also possible to acquire a part of the display data yet to be acquired when the communication with the external entity resumes. Such a method is widely put into practice by way of a download manager such as are available as freeware. A resume function included in such a download manager can be used for acquiring the data yet to be acquired.
Furthermore, the automatic display apparatus according to the fifth embodiment may comprise a storage function for a history relating to a display data acquisition method. While such a function is not necessarily required, equipment with such a function can easily reference past display data. Such a history can of course be stored in the nonvolatile memory 95 shown by
Last but not least, the descriptions are of diverse applications of the automatic display apparatus according to the fifth embodiment. In summarizing such applications, it is possible to transmit not only a mobile terminal screen as is to the automatic display apparatus, but also high resolution large screen data specifically built and transmit it to the automatic display apparatus.
The automatic display apparatus may also comprise an installer for a mobile terminal in order to install a driver for the automatic display apparatus on a mobile terminal from the automatic display apparatus. A mobile terminal generally has a small memory size, which can be used effectively by installing the driver only on as required basis and discarding it as soon as the necessity ends.
The automatic display apparatus may also be formed as a refill corresponding to replaceable pages for a day organizer, both sides of which can display data. In this case, installing antennas on both sides, comprising a magnetic shield layer in the middle, and comparing the voltages generated for the two antennas to rewrite the display data first for the side on which the higher voltage antenna is installed.
The automatic display apparatus may further allow the display unit containing the display panel and driver LSI to be detached thereof, comprise the function of erasing data of the display panel and buffer memory, or let a part of the display screen be a fixed advertisement display area so as to display in the area by downloading advertisement data at the time of updating the display data by a prescribed procedure.
Further descriptions of these example applications will be given while referring to the accompanying drawings. An automatic display apparatus shown by
Just moving a sheet type material close to a mobile phone displays an enlarged map, the entirety of a long mail message or content to be memorized, thereby providing a real convenience. A driver for the automatic display apparatus for a mobile phone can also be installed from the automatic display apparatus.
When positioning an automatic display apparatus shown by
An automatic display apparatus may be formed as a refill for a day organizer, which may be configured as capable of duplex display. Installing antennas on both sides with a magnetic shield in the middle, it is possible to identify on which side an IC card reader/writer is located. It is desirable to assign priority of data processing to the side where the IC card reader/writer is located.
The fact that the use of a plurality of displays increases the efficiency of work is well known. One can use four or five of the automatic display apparatus in taking advantage of the aspects thereof such as: its being thinner, lighter and taking less space than the conventional display; allowing use in a free layout; and is less expensive as compared to the usual display. It is a required item for comfortably reading an online manual with deep nesting.
Next, an automatic display apparatus according to the present embodiment is equipped with a wireless LAN interface and a battery. The automatic display apparatus starts up automatically when the owner's desktop PC is started up followed by completing authentication of the owner. The automatic display apparatus requests the desktop PC to transmit personnel schedule chart data. The desktop PC, having a driver for the automatic display apparatus installed, transmits the personnel schedule chart data. The automatic display apparatus displays a personnel schedule chart in the display panel, followed by transitioning itself automatically to the ready state in which the display unit of the automatic display apparatus can be detached.
Quite a few personnel print a personnel schedule chart every day, consuming approximately 250 sheets of paper a year per person. A use of the automatic display apparatus not only saves the time and effort required to print a personnel schedule chart but also reduces paper consumption and paper waste volume.
An automatic display apparatus according to the present embodiment is equipped with a noncontact IC card reader/writer (i.e., antenna and IC chip). When positioning the automatic display apparatus close to a mobile phone equipped with an IC card reader/writer, the automatic display apparatus requests transmission of a newspaper article. The mobile phone, having a driver for the automatic display apparatus installed, downloads the newspaper article from the newspaper home page to transmit to the automatic display apparatus which carries out display drive control in response to the power supplied by the mobile phone to display the newspaper article in the display panel, followed by transitioning itself to the ready state.
Just positioning a sheet shaped object close to the mobile phone enables a reading of the latest newspaper article, providing great convenience. The same technique can be applied to an electronic book. There is no need of a pre-download, hence making it possible to start reading a paperback book or magazine on hanging poster in trains, which has caught the eye right then and there. This practice is much more convenient and comfortable as compared to an electronic book by the method for downloading onto a secure digital (SD) card for the purpose of protecting a copyright.
An automatic display apparatus according to the present embodiment is equipped with a wireless LAN interface and a battery. The automatic display apparatus starts up automatically when starting up the owner's desktop PC, and requests the desktop PC to transmit a newspaper article. The desktop PC, having a driver for the automatic display apparatus installed, downloads the newspaper article from the newspaper home page to transmit to the automatic display apparatus which then displays the newspaper article according to the size of display panel (i.e., A6 through a two-page spread of A3 sizes), followed by transitioning itself to the ready state. The automatic display apparatus allows the display unit to be detached in the ready state.
Use of the automatic display apparatus eliminates printing, delivery or distribution to each subscriber (including private homes), providing news at a less expensive subscription fee, as well as much more timely news articles, as compared to conventional newspapers, while reducing paper consumption and paper waste volume.
Many automatic display apparatuses shown by
A use of the automatic display apparatus reduces printing costs, installation costs, paper consumption and paper waste volume. A continued installation of a PC in a train car will enable switching of advertisements in response to the time of day, running zone of the train service, et cetera. The same technique can be applied to merchandize price displays at a store such as a supermarket.
Next, many automatic display apparatus used for a building wall advertisement are hung on a building wall, with each comprising a Bluetooth interface and a battery. A Bluetooth enabled laptop PC is installed in the building and connected with antennas installed in a plurality of places on the wall. One of the automatic display apparatuses starts up because of a startup instruction issued by the laptop PC to request for transmission of advertisement data. The laptop PC, being installed by a driver for the automatic display apparatus, transmits the advertisement data to be displayed by the started automatic display apparatus which then displays the advertisement in the display panel, followed by automatically transitioning itself to the ready state. A series of operations will be repeated until completion of display content update for all the applicable automatic display apparatus. In the case of a plurality of automatic display apparatuses displaying a large screen, each display requires only the image data for the assigned part, and therefore image cutout processing is easy.
Use of the automatic display apparatus reduces printing and installation costs. It is also possible to switch the advertisement contents entirely depending on the time of day. The same technique can be applied to the train schedule at a station.
Many automatic display apparatuses for use as a handout at a conference shown by
Use of the automatic display apparatus reduces printing costs, book binding costs, paper consumption and paper waste volume. Suddenly required material during the meeting can be distributed in no time. Furthermore, the use of the automatic display apparatus improves security by taking advantage of the capability to erase the display panel and buffer memory data of any classified material as soon as the meeting is adjourned.
The next description is of a usage example of a mobile display having an advertisement display function. This is similar to the screen enlargement display for mobile equipment as shown by
As described above, the fifth embodiment is comprised to accomplish an automatic display apparatus using a convenient electronic paper which highly integrates the characteristics of starting up the automatic display apparatus without operating a PC, et cetera, having the latest information displayed by positioning a noncontact IC card close to an IC card reader/writer equipped in a PC or PDA for example and retaining the display even if the power supply is cut off with the characteristic of the display content being discretionarily rewritable.
The present invention is applicable to not only industries producing IC cards, electronic papers, liquid crystal display devices and mobile equipments including mobile terminals and digital cameras, but also all industries using these display apparatuses, display devices and mobile equipment.
This application is a continuation of PCT application No. PCT/JP2003/011314, which was filed on Sep. 4, 2003.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP03/11314 | Sep 2003 | US |
| Child | 11276173 | Feb 2006 | US |
