JP2001338273A - Laminated power generation display type ic card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated power generation display type IC card, with which a display area is expanded by laminating a solar cell on the back surface of a liquid crystal display part, concerning an IC card having the display part. SOLUTION: Concerning a laminated power generation display type IC card 10, on a display type IC card having both a reflection type liquid crystal display part 12 and a solar cell, the solar cell for power generation is provided, while being laminated on the back of the liquid crystal display part on the front side of the card and a display part driving power is generated by beams transmitted through a liquid crystal layer. By using polymer network type liquid crystal materials for the liquid crystal layer of such a reflection type liquid crystal display part, transparency can be improved and electromotive force can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a stacked power generation display type IC card. More specifically, the present invention relates to a private power generation type IC card having a solar cell, in which the solar cell is provided on the back surface of the liquid crystal display section so that the display area of the card can be increased.

[0002]

2. Description of the Related Art Data recorded on an IC of an IC card,
There are many needs for displaying content data exchanged with the outside through an IC card and a reader / writer. For example, the history and balance of electronic money in the financial industry. This is a display of credit settlement history, debit, point balance, and the like. Also,
In the distribution industry, there are graphic displays such as purchase history data and maps, and a display that makes extensive use of the entire card is required.
In addition, applications that need to be displayed, such as FSP (Frequency Shoppers Program), display product names and purchase histories, and multiple applications installed in a multi-application type IC card such as a MULTOS card or a JAVA (registered trademark) card. Need to show an outline and expiration date. In the medical field,
There is a map of the hospital and the display of the contents of the appointment for the return when using it for the medical history, medical history, and consultation ticket.

Since such display consumes power consumption, it is necessary to provide a self-generating solar cell in order to operate the IC with the power generated by itself without using a battery and to perform display. Become. Conventionally, when a display type IC card is provided with a solar cell, it is necessary to use the solar cell on the surface of the card. Therefore, the display area is limited, so that a sufficient display cannot be performed or a display that is difficult to see. Did not get.

Japanese Patent Laid-Open Publication No. 1-115690 discloses a technique for attaching a display unit and a solar cell to a card.
The solar battery is required to be exposed on the surface of the IC card, and the liquid crystal display panel is provided at a position separate from the solar battery. Therefore, the area of both the liquid crystal display unit and the solar battery is reduced, and sufficient functions cannot be exhibited.

[0005]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a liquid crystal display unit using a liquid crystal material having excellent light transmittance, particularly a polymer network type liquid crystal, so that a solar cell is laminated on the back of the liquid crystal display unit. In addition to increasing the area of the display unit, the area of the solar cell is also increased to increase the power generation capacity.

[0006]

A first aspect of the present invention to solve the above-mentioned problem is that in a display type IC card having both a reflection type liquid crystal display section and a solar cell, the solar cell for power generation is a card. There is provided a stacked power generation display type IC card which is provided so as to be laminated on the rear surface of a liquid crystal display portion and generates display portion driving power by light rays transmitted through the liquid crystal layer. Since such a display type IC card is used, it is possible to increase the area of the display unit and obtain driving power.

When a polymer network type liquid crystal material is used in the liquid crystal layer of the above-mentioned reflection type liquid crystal display portion, light contributing to electromotive force is reduced to 3 in a white scattering portion which is a non-image portion.
0-50% is obtained, and the transparency at the time of transmission is high, so that the electromotive force of the solar cell can be increased. If the solar cell also serves as the reflector of the liquid crystal display section, the reflective layer is particularly provided. It is possible to make the liquid crystal display easy to see without the need.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a stacked power generation display type I of the present invention will be described.
The C card will be described with reference to the drawings. FIG. 1 is a plan view showing an example of the display type IC card of the present invention. The overall outer shape of the stacked power generation display type IC card 10 is rectangular (85 mm × 55 mm) conforming to the card standard.
The outer frame 10f can be formed into a substantially constant thickness as a whole. For the liquid crystal display section 12, a film-like reflective liquid crystal panel is used for reducing the card thickness and facilitating lamination. The area other than the liquid crystal display section 12 may be a general print information display section 13 of the card or an emboss area 14 for specifying a user of the card. Reference numeral 17 denotes a touch panel type push button switch for switching the display on the liquid crystal display unit. A print information display section, an embossed area, and the like may be provided on the front surface of the card, and the liquid crystal display section may be provided on the back side of the card. In the liquid crystal display section, a display 15 such as a character is made by a matrix or a segment. This liquid crystal display 1
For 2, a polymer network type liquid crystal is used as described later, a non-image portion uses a white state in which the polymer network type liquid crystal exhibits an uncharged state, and an image portion shows a current-transmitted transmission state. It uses a scattered light and a transmitted light of the image area in the solar cell on the back to generate power.

Although FIG. 1 shows a non-contact type IC card having no contact terminal with an external device, the IC card may be of a contact type, in which case the contact terminal appears on the surface. In the case of the non-contact type, since the opportunity to receive power supply from the outside is limited, the power generation display type I of the present invention is used.
It is preferable to use a C card. Further, in the case of a non-contact type IC card, it is usual that the IC chip 18 is embedded and an antenna coil connected thereto is provided. In the drawing, the dotted line indicates that the antenna coil 16, the IC chip 18, the liquid crystal driving driver 20, and the like are embedded in the card base.

FIG. 2 is a diagram showing a laminated structure of the IC card of the present invention, and shows a cross section taken along line AA of FIG. The dimension in the thickness direction of the IC card is shown in an enlarged manner. The card base 11 includes a lower center core 111 having an antenna coil 16, an upper center core 112 having a button switch 17 and an IC chip 18 between itself and the lower center core, oversheets 113 and 114, and a sheet-like solar cell 19. And a liquid crystal display 111 (liquid crystal display unit) 12 in the form of a film. The oversheets 113 and 114 can be omitted. The display type IC card thus configured has an overall thickness of 0.6 to 2.
It can be about 0 mm.

The connection terminals 161 and 1 of the antenna coil 16
Reference numeral 62 is formed so as to face the IC chip embedded recess 21 of the upper center core 112, and is connected to a bump (not shown) of the IC chip. Circuit elements such as a receiving circuit and a liquid crystal drive driver 20 for driving the liquid crystal display panel 12 are also accommodated between the core sheets. The drive driver 20 and the electrode terminals of the liquid crystal display panel 12 are connected by a connector or the like,
Appropriate circuits are also formed between the solar cell, the button switch, and the IC chip. The button switch 17 performs a blinking operation of the liquid crystal display unit 12 and a switching operation of the display. When the button switch 17 is pressed, the display ON → display 1 → display 2 → display 3 → display OFF,
Works like

FIG. 3 is an enlarged sectional view showing a liquid crystal display panel and a solar cell. As shown in FIG. 3, the liquid crystal display panel 12 and the solar cell 19 are used in a stacked state. The liquid crystal display panel 12 is not limited to a color display in the present invention, but may be a display capable of displaying characters, numerals, and the like by matrix or segment display. Therefore, no color filter is used. The liquid crystal display panel 12 includes a substrate 121 made of a flexible, tough and lightweight plastic material.
The electrodes 123 and 124 are provided on the surface of the liquid crystal material 122 in contact with the liquid crystal material, and the inside is filled with a liquid crystal material 125 and a spacer material. The four circumferences of the panel are sealed with a sealant such as an adhesive.

The solar cell 19 includes a metal substrate 1 also serving as an electrode.
91, an amorphous silicon layer 194 is laminated on a substrate made of, for example, stainless steel, aluminum, chromium, etc.
What constitutes an N-type solar cell is generally used. Since sunlight (or indoor fluorescent lamp light) is generally incident from the P-type silicon layer side, I
A transparent electrode 193 such as TO is provided, and a transparent plastic substrate is further provided as a protective layer 192. Such a solar cell is a commercially available solar cell, can generate an electromotive force of about 1.5 V and 3 μA, and has a driving voltage of an LSI used for a card or a calculator.
Power suitable for the current is obtained. In this configuration, the light L incident from the card surface is reflected by the metal substrate 191 and re-transmits through the liquid crystal panel. When the metal substrate is reflective, the effect of increasing the electromotive force of the solar cell is produced. In general, the surface of a solar cell viewed from the incident light side has a unique dark coloration, so that external light reflected from the metal substrate and returned from the opaque portion (uncharged state) of the liquid crystal layer is in a white state. Although a preferable contrast is produced, the contrast with the non-image area can be further enhanced by interposing a filter having a wavelength dependency such as a hologram or a cold mirror.

The solar cell 19 is a power source that mainly supplies a voltage to the electrodes of the liquid crystal layer to switch between a transparent state and a scattering state, but can also be used for driving an LSI as described above. The liquid crystal display panel 12 utilizes reflected light and is not illuminated from the back, so that it does not require excessive power supply. On the other hand, since the display type IC card is usually used outdoors or in a brightly lit store, a sufficient electromotive force can be generated by the illumination light.

FIG. 4 is a block diagram showing an electric circuit of the stacked power generation display type IC card. The signal from the external device received from the antenna is sent to the microprocessor 18p in the IC chip via the receiving circuit 16k. The receiving circuit is a resonance circuit that forms an LC circuit with an antenna coil and a capacitor, and the microprocessor demodulates the received signal and performs input / output processing to the memory and the liquid crystal driving driver 20 and arithmetic processing.

The substrates 121 and 122 of the liquid crystal display panel 12
In addition to a polyethylene terephthalate film, a film such as a polybutylene terephthalate film, a polyethersulfone film, and a polycarbonate film is used. An electrode made of a transparent conductive film such as indium oxide or tin oxide is formed on the inner surface of the film by known means, and a spacer agent or the like is applied or sprayed. In the case of the segment type, the liquid crystal layer is provided on the entire surface, but the electrodes are provided in a pattern only on the portion where the segment to be displayed exists. However, one side of the electrode may be a planar electrode as a common electrode.

The liquid crystal is a polymer network type liquid crystal material (PN-LCD) as described in JP-A-7-333584. That is,
A light scattering type liquid crystal display in which a light control layer containing a liquid crystal material and a transparent solid substance is formed between two substrates is preferable. In this device, as shown in FIG. 5, a polymer forms a network in a transparent three-dimensional network polymer, and a liquid crystal supported by the network forms a continuous layer, so that a white-transparent display mode can be performed. .

When a voltage is applied, the liquid crystal molecules are arranged in parallel to the direction of the incident light as shown in FIG. 5B, so that the liquid crystal becomes transparent and transmits the light, or in the case of the reflection type, reflects the light in parallel. On the other hand, in the random state where no voltage is applied, (A)
As a result, the incident light is scattered. The layer having the transparent solid substance has a thickness of 1 to 30 μm. In the case of a normal liquid crystal display device, a polarizing film is used. However, in the case of the display type IC card of the present invention, since a scattered light is used, it is not necessary to use a polarizing film and a white and bright screen can be obtained. The reflectance is from 20% to 35 for high reflectance.
It is said that the percentage can be realized. PN-LCD (Polym
er Network Liquid Crystal
Display) can be produced by irradiating the raw material composition for forming a light control layer between electrode substrates with ultraviolet light.

Next, a method of manufacturing a stacked power generation display type IC card will be described. FIG. 6 is a diagram showing a manufacturing process of the stacked power generation display type IC card. Although such an IC card can employ various manufacturing methods, an example of manufacturing a non-contact type IC card using a two-layer core sheet will be described as an example. It is necessary to provide the antenna coil 16 on the lower center core 111, and a base material laminated with aluminum foil or copper foil is used. After forming an antenna pattern on the surface of the metal foil with a printing resist or a photoresist, the antenna pattern is etched to leave the antenna coil. After both connecting ends of the antenna coil are formed so as to face the IC chip embedding recess 21 of the upper center core 112, I
The bumps of the C chip 18 are mounted using an anisotropic conductive film, a conductive adhesive, or the like (FIG. 6A).

In this case, the two connection ends of the coil may be located on both sides of the coil, and the two bumps may be connected so that the IC chip straddles the coil, as shown in FIG.
A jumping circuit may be formed at any part of the coil to mount an IC chip. Since the height of the IC chip 18 can be set to 0.2 mm or less, it is not necessary to form the recess 21 for embedding the IC chip so as to penetrate the center core 112.

After the IC chip 18 is mounted, the upper center core 112 and the solar cell 19, the film-shaped liquid crystal display panel 12, the over sheet 113 when used,
114 are laminated using a transparent adhesive and laminated (FIG. 6B) to complete the laminated power generation display type IC card 10 (FIG. 6C). In this case, application of heat or excessive pressure adversely affects the solar cell or the liquid crystal panel, so that the pressure is set to a level that can maintain a planar state. The upper center core 112 provided between the solar cell and the liquid crystal panel includes:
As shown in FIG. 2, a concave portion 22 corresponding to the lamination thickness may be provided and placed.

[0022]

EXAMPLES (Example) First, 350 μm of white rigid PVC sheet was used as the upper and lower center cores of the card. The lower center core was a sheet in which aluminum foil having a thickness of 30 μm was laminated. A resist was printed on the core sheet in an antenna coil shape, and then the antenna coil 16 was formed by etching. The IC chip 18 was connected to both connection ends of the antenna coil, and a driver 20 for driving a liquid crystal, a button switch 17, a receiving circuit, and the like were mounted. The lower center core is overlaid with an upper center core provided with a connection portion for the solar cell 19 and the liquid crystal display panel 12, and pressed at 80 to 90 ° C. and 5 to 10 kg / cm ² to form an integrated card. A substrate was formed.

In another step, a liquid crystal panel was prepared.
For the liquid crystal layer of the liquid crystal display panel 12, a polymer network type high reflectance liquid crystal raw material composition ("PLN-105" manufactured by Dainippon Ink and Chemicals, Inc.) is used.
Electrodes are formed on the upper and lower substrates 121 and 122 using a polyethylene terephthalate film (manufactured by Toray Industries, Inc.) having a thickness of 40 μm, and the distance between the electrodes 123 and 124 is 11 μm.
m, the liquid crystal material composition is sandwiched between substrates coated with a glass fiber spacer agent having a diameter of 11 μm so as to be maintained at m, and then irradiated with a light-scattering ultraviolet light source to cure the polymerizable compound. Scattering type liquid crystal display device (PLN
-105) was obtained. The area between the upper and lower substrates of the liquid crystal panel
It was adhered and sealed with a liquid-curing adhesive and sealed.

On the other hand, the solar cell 19 has "Amorton AL-1406" (37.0 × 17.
0 × 0.2 mm thick). The operating voltage of the solar cell is 1.5V. The solar cell 19 was adhered to the back surface of the liquid crystal display panel 12 with a transparent adhesive, and after making necessary circuit connections, the solar cell 19 was adhered to the previously prepared card base to complete an IC card. A power generation display type IC having a thickness of about 1.2 mm by attaching an oversheet (0.1 mm thick polypropylene film) for protection to the upper and lower surfaces of this IC card.
Completed the card.

When this stacked power generation display type IC card was operated under sunlight or a fluorescent lamp, a sufficient electromotive force was obtained, and a clear liquid crystal display was obtained.

[0026]

As described above, the stacked power generation display type IC card of the present invention uses a film-type reflection type liquid crystal display element for the liquid crystal display portion of the IC card, and stacks solar cells on the back surface thereof. Therefore, it is possible to generate power in-house, and at the same time, to increase the display area to make it easier to see and to increase the amount of display information. When a PN-LCD is used for the liquid crystal, the non-charged portion of the liquid crystal is in a cloudy state, and the charged portion, which is a non-image portion, is clearly distinguished from the transparent state. The contrast of this display can be made clearer by the inherent coloring of the solar cell surface.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a display type IC card of the present invention.

FIG. 2 is a diagram showing a stacked configuration of the IC card of the present invention.

FIG. 3 is an enlarged sectional view showing a liquid crystal display panel and a solar cell.

FIG. 4 is a block diagram showing an electric circuit of the stacked power generation display type IC card.

FIG. 5 is a diagram illustrating a polymer network type liquid crystal.

FIG. 6 is a diagram showing a manufacturing process of the stacked power generation display type IC card.

[Description of Signs] 10 Stacked power generation display type IC card 11 Card base 12 Liquid crystal display panel (liquid crystal display unit) 13 Print information display unit 14 Emboss area 15 Display of characters etc. 16 Antenna coil 17 Button switch 18 IC chip 19 Solar cell 20 Liquid crystal drive driver 21 IC chip embedded recess

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02F 1/1335 520 G06K 19/00 J 5B035 G06K 19/077 K 5F051 H01L 31/04 H H01L 31/04 Q F-term (reference) 2C005 MA40 MB01 MB02 MB08 MB10 NA09 PA03 PA04 PA15 QA02 QB01 RA06 RA11 RA15 RA16 2H088 EA22 GA10 HA01 HA02 HA07 HA21 MA16 2H089 HA04 JA04 LA08 NA44 NA58 QA11 QA13 TA01 TA08 TA17 2H091 FA14 GA02 GA08 MA10 2H093 NC07 ND22 NE01 NE03 NE06 NG01 5B035 BA03 BA05 BB09 CA01 CA06 CA23 5F051 BA05 BA12 JA14 JA20

Claims (3)

[Claims] 1. A display type IC card having both a reflection type liquid crystal display portion and a solar cell, wherein a solar cell for power generation is provided on the back surface of the liquid crystal display portion on the surface of the card, and transmits through the liquid crystal layer. A stacked power generation display type IC card, wherein a display unit driving power is generated by a light beam. 2. The liquid crystal layer of the reflection type liquid crystal display section is made of a polymer network type liquid crystal material.
The stacked power generation display type IC card as described in the above. 3. The stacked power generation display type IC card according to claim 1, wherein the solar cell also serves as a reflection plate of the liquid crystal display unit.