U.S. patent application number 09/112497 was filed with the patent office on 2001-06-14 for integrated circuit card with liquid crystal display for viewing at least a portion of the information stored in the card.
Invention is credited to GAUTHER, DOMINIQUE, GOODELL, JOHN L., GOZLAN, GILLES, MUNCH, MARK R., TOMITA, AKIRA.
Application Number | 20010003445 09/112497 |
Document ID | / |
Family ID | 22344223 |
Filed Date | 2001-06-14 |
United States Patent
Application |
20010003445 |
Kind Code |
A1 |
GAUTHER, DOMINIQUE ; et
al. |
June 14, 2001 |
INTEGRATED CIRCUIT CARD WITH LIQUID CRYSTAL DISPLAY FOR VIEWING AT
LEAST A PORTION OF THE INFORMATION STORED IN THE CARD
Abstract
An integrated circuit card contains a liquid crystal display for
displaying at least a portion of the information stored therein.
The displayed information is stored in a first, or reserved,
memory. A second, or additional, memory is used to store further
information. The use of a reserved memory for storing the displayed
information permits the use of very low power electrical energy
sources for driving the display and the electronics controlling the
pixels of the display, such as piezoelectric sources, pyroelectric
sources, photovoltaic cells, and very small batteries. The first
and second memories may be integrated into a single IC chip, or
they may be separate components.
Inventors: |
GAUTHER, DOMINIQUE;
(LEVALLOIS-PERRET, FR) ; MUNCH, MARK R.; (PALO
ALTO, CA) ; TOMITA, AKIRA; (REDWOOD CITY, CA)
; GOODELL, JOHN L.; (SUNNYVALE, CA) ; GOZLAN,
GILLES; (LEMESNIL THERIBUS, FR) |
Correspondence
Address: |
TYCO ELECTRONICS CORPORATION
MAIL STOP R20/2B
307 CONSTITUTION DRIVE
MENLO PARK
CA
94025
US
|
Family ID: |
22344223 |
Appl. No.: |
09/112497 |
Filed: |
July 9, 1998 |
Current U.S.
Class: |
345/87 |
Current CPC
Class: |
G06K 19/07 20130101;
G06K 19/07703 20130101; G06K 19/077 20130101 |
Class at
Publication: |
345/87 |
International
Class: |
G09G 003/36 |
Claims
What is claimed is:
1. An integrated circuit card capable of displaying at least a
portion of information stored therein, comprising: a. a card-shaped
support; b. a reprogrammable nonvolatile first memory on the
support, for storing information to be displayed; c. an integrated
circuit chip on the support, comprising i. a reprogrammable
nonvolatile second memory for storing additional information; and
ii. a serial port on said support for interfacing the integrated
circuit chip with an external controller device; and d. a liquid
crystal display on the support, the liquid crystal display having
plural pixels wherein, when the liquid crystal display is driven,
the optical state of each pixel is determined by the state of a
corresponding bit of information stored in the first memory; e.
plural parallel output ports connecting each pixel of the liquid
crystal display to the corresponding bit of information stored in
the first memory; and f. an electric energy source on the support,
for driving the first memory and the liquid crystal display, the
electrical energy source driving the first memory without affecting
information stored in the second memory.
2. An integrated circuit card according to claim 1, wherein the
liquid crystal display comprises a liquid crystal composite as
electrooptically active material.
3. An integrated circuit card according to claim 1, wherein the
electric energy source is a piezoelectric energy source.
4. An integrated circuit card according to claim 1, wherein the
electric energy source is a photovoltaic cell.
5. An integrated circuit card according to claim 1, wherein the
electric energy source is a battery.
6. An integrated circuit card according to claim 1, wherein the
electric energy source is a pyroelectric cell.
7. An integrated circuit according to claim 1, wherein the
information to be displayed is redundantly stored in the second
memory.
8. An integrated circuit card according to claim 1, wherein the
information stored in the first and second memories is
non-overlapping.
9. An integrated circuit card according to claim 1, wherein the
first memory is an EEPROM.
10. An integrated circuit card according to claim 1, wherein the
first memory is a flash memory.
11. An integrated circuit card according to claim 1, wherein the
integrated circuit chip further comprises logic circuits.
12. An integrated circuit card according to claim 1, wherein the
first memory is integrated with the integrated circuit chip.
13. An integrated circuit card according to claim 1, wherein the
first memory is separate from the integrated circuit chip.
14. An integrated circuit card according to claim 2, wherein the
electric energy source is a piezoelectric energy source.
15. An integrated circuit card according to claim 2, wherein the
electric energy source is a photovoltaic cell.
16. An integrated circuit card according to claim 2, wherein the
electric energy source is a battery.
17. An integrated circuit card according to claim 2, wherein the
electric energy source is a pyroelectric cell.
18. An integrated circuit according to claim 2, wherein the
information to be displayed is redundantly stored in the second
memory.
19. An integrated circuit card according to claim 2, wherein the
information stored in the first and second memories is
non-overlapping.
20. An integrated circuit card according to claim 2, wherein the
first memory is an EEPROM.
21. An integrated circuit card according to claim 2, wherein the
first memory is a flash memory.
22. An integrated circuit card according to claim 2, wherein the
integrated circuit chip further comprises logic circuits.
23. An integrated circuit card according to claim 2, wherein the
first memory is integrated with the integrated circuit chip.
24. An integrated circuit card according to claim 2, wherein the
first memory is separate from the integrated circuit chip.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to an integrated circuit card having
a liquid crystal display for viewing at least a portion of the
information stored therein.
[0003] 2. Description of Related Art
[0004] Integrated circuit (IC) cards are finding increasing
popularity as compact, highly portable information storage
articles. Also known as smart cards or chip cards, IC cards
typically are credit card sized and contain an integrated circuit
element that provides electronic data storage and/or logic function
capability. Information stored on an IC card can be widely ranging,
from financial to medical to personal identification information.
Additionally, IC cards usually contain input/output connections for
connection to an external control device that retrieves, updates,
and/or displays the stored information.
[0005] A drawback with most IC cards is that the stored information
is not immediately viewable by the bearer. While the IC card may
contain information on the bearer's bank account balance, the
bearer may not be able to see conveniently what is that balance.
One solution has been to provide a separate IC card reader that
"reads" the stored information and displays it. But such a solution
has the limitation of requiring an additional component that may
not be immediately accessible or readily portable, for example
requiring the bearer to go to the nearest bank branch or ATM
machine or to remember to bring the reader along on a trip.
[0006] Some constructions in which a display is integrated into an
IC card have been proposed, such as Jachimowicz et al., U.S. Pat.
No. 5,734,154 (1998) entitled "Smart Card With Integrated Reader
And Visual Image Display." As IC cards increase in popularity and
find applications in more and more areas of daily life, bearer
access to the stored information becomes increasingly important. At
the same time, their ubiquitousness means that IC cards are
approaching commodity item status, meant to be disposed of after a
finite number of uses, imposing strong economic pressure reduce
their cost. Further, size, weight, and ruggedness permitting an IC
card to be carried around in a wallet is an important
consideration. Lastly, due to its limited size and thickness, an IC
card offers limited electrical power storage (or generation)
capability, so that the power consumption of a display and the
electronics associated with it must be low enough.
BRIEF SUMMARY OF THE INVENTION
[0007] Thus, it is an object of this invention provides an IC card
having an integrated display for viewing at least a portion of the
information stored therein, where the display and associated
electronics have low power consumption. Another object of this
invention is to provide an IC card capable of displaying such
stored information autonomously. An IC card of this invention
preferably comprises a display employing a liquid crystal composite
(as described further hereinbelow) as electro-optically active
material, such material being especially adaptable for use in
combination with plastic substrates and leading to a flexible and
rugged IC card. These and other objects are achieved by an
integrated circuit card according to this invention,
comprising:
[0008] a. a card-shaped support;
[0009] b. a reprogrammable nonvolatile first memory on the support,
for storing information to be displayed;
[0010] c. an integrated circuit chip on the support, comprising
[0011] i. a reprogrammable nonvolatile second memory for storing
additional information; and
[0012] ii. a serial port on said support for interfacing the
integrated circuit chip with an external controller device; and
[0013] d. a liquid crystal display on the support, the liquid
crystal display having plural pixels wherein, when the liquid
crystal display is driven, the optical state of each pixel is
determined by the state of a corresponding bit of information
stored in the first memory;
[0014] e. plural parallel output ports connecting each pixel of the
liquid crystal display to the corresponding bit of information
stored in the first memory; and
[0015] f. an electric energy source on the support, for driving the
first memory and the liquid crystal display, the electrical energy
source driving the first memory without affecting information
stored in the second memory.
BRIEF DESCRIPTION OF THE DRAWING(S)
[0016] FIG. 1 shows schematically an IC card of this invention.
[0017] FIGS. 2a, 2b, and 2c show electric energy sources for an IC
card of this invention.
[0018] Reference numerals repeated from one figure to another
denote the same or like elements.
DETAILED DESCRIPTION OF THE INVENTION
[0019] An integrated circuit (IC) card 10 of this invention is
shown in FIG. 1, which is typically credit card sized, although its
size is not especially critical and it may be somewhat larger or
smaller. Preferably, IC card 10 is less than 100 mm wide (more
preferably less than 90 mm wide), less than 70 mm high (more
preferably less than 60 mm high), and less than 2 mm (more
preferably less than 1 mm) thick. Typical ISO dimensions for an IC
card are 85.5.times.54.times.0.76 mm. IC card 10 comprises a card
shaped support 11 on which the other elements of IC card 10 are
supported, for example by being partially or wholly embedded
therein or by being surface mounted thereon. Support 11 may be made
of flexible plastic, for example by molding or lamination.
[0020] On support 11 is a reprogrammable nonvolatile first memory
12a, which may be, for example, an EEPROM (electrically erasable
programmable read-only memory) or a flash memory. Also on support
11 is an IC chip 13 including a reprogrammable nonvolatile second
memory 12b. IC chip 13 is not restricted to being a memory-only
chip; it may additionally have ptional logic circuits 14 for
performing calculations on the stored data. First memory 12a is a
reserved memory, for storing the information to be displayed by IC
card 10. If IC card 10 is used, by way of illustration, for a bank
account, the information in first memory 12a may be key information
such as the account balance. Second memory 12b, normally larger in
size than first memory 12a, may store additional, less key
information (such as, continuing the illustration, recent deposits
and withdrawals, interest earned, etc.). The information stored in
first memory 12a may be redundantly stored in second memory 12b, or
the information stored in first and second memories 12a, 12b may be
non-overlapping, i.e., mutually exclusive. IC chip 13 includes a
serial input/output (I/O) port 18 for communicating with an
external interface unit 19 (also known in the art as a card
reader/writer), for updating the information stored in first and
second memories 12a, 12b. Alternatively, the information destined
for first memory 12a can be stored in second memory 12b first (or
computed there, if IC chip 10 is equipped with logic circuits 14)
and then transferred to first memory 12a. Communication between IC
card 10 and interface unit 19 may be with contact or without
contact, for example through an RF antenna system. Most existing
protocols, including ISO 7816, may be used for communication
between IC card 10 and interface unit 19.
[0021] Plural parallel ports (outputs) 15 link first memory 12a
with a liquid crystal display 16, one port per pixel of the latter.
A local electrical energy source 17 powers IC chip 13 and liquid
crystal display 16. In a preferred embodiment, local energy source
powers 17 only first memory 12a. Alternatively, local electrical
energy source 17 powers IC chip 13, but only first memory 12a is in
the "read" mode, while the rest of IC chip 13 is in the stand-by
mode. According to the state of each bit of information in first
memory 12a (0 or 1), the corresponding pixels in liquid crystal
display 16 will be powered on or not, thus causing a pattern to be
displayed. Segregation of the displayed information in memory 12a
prevents the information of second memory 12b from being corrupted
accidentally.
[0022] It is to be understood that the terms "first" and "second"
memories are used to identify which of the memory components in
integrated circuit card 10 have a parallel port 15 connected
thereto or not. There are no rigid numerical limitations on the
(digital) size of memories 12a, 12b, but first memory 12a should
have at least as many memory cells as there are parallel ports 15.
First memory 12a may be separate from IC chip 13--i.e., a separate
component on card 10 distinct from IC chip 13--or it may be
integrated therewith. Further, where integrated, first memory 12a
may be "dispersed" within second memory 12b or it may occupy a
segregated block within IC chip 13.
[0023] Because the information content of first memory 12a is
limited, very little power is required to drive the system. When IC
card 10 is in communication with interface unit 19, interface unit
can provide more power, driving the entire IC chip 13, and
information on both first and second memories 12a, 12b can be
addressed. Thus, an IC card of this invention permits substantial
amounts of information to be stored, with key portions thereof
always available for viewing by the bearer, even when the card is
in its autonomous mode, i.e. not in communication with another
device or an external power source. When the card is connected to
interface unit 19, or is inserted into a separate reader unit (not
shown) having more power, all the information stored in the IC card
may be viewed on an appropriate display (liquid crystal,
electrochromic, plasma, etc.) associated with interface unit 19 or
the reader unit. Driving a liquid crystal display with conventional
driver IC's requires significant electrical power. In the
invention, driving liquid crystal display 16 via a memory chip
alone (or a memory component alone of a logic-plus-memory chip)
allows one to reduce drastically power consumption, thus enabling
the use of a much smaller power source. Moreover, by bifurcating
the total information stored and the information displayed in the
autonomous mode, power consumption can be further reduced.
[0024] Besides requiring very little power, the present invention
is advantageous in its simplicity. No separate driving circuit is
required; rather, first memory 12a and liquid crystal display 16
are directly driven by electric energy source 17. The absence of a
need to power a separate driving circuit also contributes to
reduced power consumption. The minimal power requirements mean a
wide range of electric energy sources 17 can be used with IC card
10, including power sources incompatible with IC cards not
according to this invention. Such "local" power sources include
piezoelectrically actuated energy sources, pyroelectric energy
sources, batteries, and solar cells.
[0025] FIG. 2a shows the circuit diagram of an exemplary
piezoelectric energy source 20 that can be used as an electric
energy source 17, comprising a piezoelectric element 21, a
rectifier 22, and a capacitor 23. Electric energy is generated by
inputting mechanical work energy, for example by pressing down on a
diaphragm made of piezoelectric material. Suitable piezoelectric
elements 21 include piezoelectric diaphragms of the external
drive/self drive type available from Murata Manufacturing Co.,
Ltd., of Kyoto, Japan (http://www.murata.co.jp/), for instance as a
25 mm disk of piezoelectric material on a brass disk (product no.
VSB41D25-07AR0, 140 nF capacitance). Rectifier 22 may be a
rectifier bridge such as Multicomp DB 103G. Capacitor 23 may be a
0.1 .mu.F metallized polyester film capacitor (Philips, no.
222237011104). The rectifier 22/capacitor 23 combination serves to
supply first memory 12a and liquid crystal display 16 with DC
voltage. In an alternative embodiment, the rectifier bridge may be
replaced by a single diode. In yet another alternative embodiment,
capacitor 23 may be omitted. In yet another alternative embodiment,
piezoelectric element 21 may be directly connected to first memory
12a, if the latter supports reverse polarity.
[0026] FIG. 2b illustrates an alternative electric energy source
17, in the form of a battery 25, which can be for example a lithium
polymer battery or a button cell. In such instance, a switch 26
controls the driving (or not) of first memory 12a and liquid
crystal display 16. Because of the low power requirements, a much
smaller battery can be used, compared to other designs.
[0027] FIG. 2c shows yet another alternative electric energy source
17, in the form of a photovoltaic (solar) cell 27, also controlled
by a switch 26. The latter is optional, because a photovoltaic
cell, unlike a battery, is not susceptible to being drained.
[0028] Where electric energy source 17 is a pyroelectric cell, it
may be based on certain piezoelectric materials that also display a
pyroelectric effect or on thermocouples displaying a Seebeck
effect.
[0029] As noted above, first memory 12a may be an EEPROM, for
example product no. 84041P available from Xicor, Inc., Milpitas,
Calif. (http://www.xicor.com/) or product no. 28C16A available from
Microchip Technology, Inc., Chandler, Ariz.
(http://www.microchip.com/).
[0030] One type of liquid crystal display for which the present
invention is especially suitable employs a liquid crystal composite
comprising plural volumes (or droplets) of liquid crystals
contained (i.e., dispersed, encapsulated, or embedded) within a
polymer matrix, as the electro-optically active material. Such
composites have been referred to in the art alternatively as
encapsulated liquid crystal material, nematic curvilinear aligned
phase (NCAP) materials or as polymer dispersed liquid crystal
(PDLC) materials. Exemplary disclosures include Fergason, U.S. Pat.
No. 4,435,047 (1984); West et al., U.S. Pat. No. 4,685,771 (1987);
Pearlman, U.S. Pat. No. 4,992,201 (1991); Andrews et al., U.S. Pat.
No. 5,202,063 (1993); Kamath et al., U.S. Pat. No. 5,233,445
(1993); Reamey, U.S. Pat. No. 5,328,850 (1994); Reamey et al., U.S.
Pat. No. 5,405,551 (1995); Wartenberg et al., U.S. Pat. No.
5,427,713 (1995); Reamey et al., U.S. Pat. No. 5,543,944 (1996);
Havens et al., U.S. Pat. No. 5,585,947 (1996); Cao et al., U.S.
Pat. No. 5,738,804 (1998); Raychem WO 96/19547 (1996); and
Dainippon Ink, EP 0,313,053 (1989); the disclosures of which are
incorporated herein by reference. Generally, such composites are
light scattering and/or absorbing in the absence of a sufficient
electric field (the field-off state), but are substantially light
transmissive in the presence of such electric field (the field-on
state). Displays made with encapsulated liquid crystal material are
especially suitable for the present invention, because they are
field-effect devices, consuming very low amounts of power. Also,
they can be made by lamination between two pieces of plastic (as
opposed to glass) substrates, so that they are flexible and rugged.
A membrane switch can be integrated with the display, for example
where the electric energy source is a battery.
[0031] However, other types of liquid crystal displays should be
suitable, including twisted nematic (TN) displays. Generally, any
type of liquid crystal display that is amenable to being driven
directly and tolerates short term exposure to DC current may be
used.
[0032] The foregoing detailed description of the invention includes
passages that are chiefly or exclusively concerned with particular
parts or aspects of the invention. It is to be understood that this
is for clarity and convenience, that a particular feature may be
relevant in more than just the passage in which it is disclosed,
and that the disclosure herein includes all the appropriate
combinations of information found in the different passages.
Similarly, although the various figures and descriptions herein
relate to specific embodiments of the invention, it is to be
understood that where a specific feature is disclosed in the
context of a particular figure or embodiment, such feature can also
be used, to the extent appropriate, in the context of another
figure or embodiment, in combination with another feature, or in
the invention in general.
[0033] Further, while the present invention has been particularly
described in terms of certain preferred embodiments, the invention
is not limited to such preferred embodiments. Rather, the scope of
the invention is defined by the appended claims.
* * * * *
References