CA1230436A - Card calling telephone system - Google Patents
Card calling telephone systemInfo
- Publication number
- CA1230436A CA1230436A CA000477381A CA477381A CA1230436A CA 1230436 A CA1230436 A CA 1230436A CA 000477381 A CA000477381 A CA 000477381A CA 477381 A CA477381 A CA 477381A CA 1230436 A CA1230436 A CA 1230436A
- Authority
- CA
- Canada
- Prior art keywords
- card
- telephone
- calling
- signal information
- optical
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Control Of Vending Devices And Auxiliary Devices For Vending Devices (AREA)
- Prepayment Telephone Systems (AREA)
- Meter Arrangements (AREA)
Abstract
CARD CALLING TELEPHONE SYSTEM
Abstract A card calling telephone system in which information is transformed bidirectionally between the card and the telephone by way of optical pulses. To this end, the card includes a photovoltaic cell to be illuminated by the telephone for powering the card's electronics, a photodiode for receiving optical signal pulses from the telephone, a display for generating optical signal pulses for transferring information to the telephone, and control circuits including an E2PROM and a microprocessor.
Information which can be stored in the E2PROM under control of the telephone includes a list of numbers frequently called and the amount of prepaid credit remaining on the card.
Abstract A card calling telephone system in which information is transformed bidirectionally between the card and the telephone by way of optical pulses. To this end, the card includes a photovoltaic cell to be illuminated by the telephone for powering the card's electronics, a photodiode for receiving optical signal pulses from the telephone, a display for generating optical signal pulses for transferring information to the telephone, and control circuits including an E2PROM and a microprocessor.
Information which can be stored in the E2PROM under control of the telephone includes a list of numbers frequently called and the amount of prepaid credit remaining on the card.
Description
~ ~3~36 CARD CALLIN~ TELEPHONE SYSTEM
Background of the Invention The present invention relates to a card telephone calling system and, more particularly, to one in which the calling cards are provided with built-in information to adapt them to specific functions.
In the typical card telephone calling system, information is transferred from the card, usually for control purposes, to the telephone in which the card is inserted, but there is little information transferred from the telephone back to the card because there has not been known a way to do this reliably. This has restricted the functions for which a card may be used.
The present invention relates to a card calling telephone system in which information is transferred both from and to the card.
It would be desirable to use a calling card in the following ways if each could be readily done. It would be desirable if the card would permit a call to be made without the need for any cash transfer at the time but with a minimum need for extraneous record keeping or follow-up billing. This can be accomplished if there is provided a card in which there is built in a certain calling capacity for which the owner has previously paid, and which capacity is automatically reduced by an appropriate amount as the card is used. Moreover, the calling capacity of the card should be readily reinstatable without the need for replacing the card.
Additionally, an ideal calling card system ~ould provide for the rapid-call feature in which -the subscriber stores in the card a group of telephone numbers frequently called from which a particular one can be easily selected for use in making a call automatically. Mor~over, the subscriber should have the ability to change this information at will with a minimum of inconvenience.
While the desirability of these functions has ~ ~3~3~
probably been generally recognized, systems including them are not presently available. The present invention is believed to present a novel system which is capable of such functions involving the bilateral transfer oE
information between the telephone and the card.
the Invention A card calling system in accordance with the present invention is characterized by the use of optical signals both for transferring information from the card to the telephone for transferring information from the telephone back to the card, and for powering the card.
In particular, it includes a card which is provided with photosensitive means adapted to be illuminated with light from the telephone. Such light is used both to power the electronics on the card and to transfer information in the form of optical pulses from the telephone to the card. Additionally, the card includes provision for generating appropriate light pulses when information is to be transferred from the card to the telephone. Conversely, in such a system, the telephone is provided with photosensitive means for receiving the optical pulses generated by the card for transferring information to the telephone and light source means for illuminating the card appropriately when information is being transferred to the card and for powering the card.
The card further includes the necessary electronics including, for example, a nonvolatile semiconductor memory in which is stored the information necessary for the functions expected of it and which can be programmed by information supplied by optical pulses from the telephone. Typically, the memory is adapted to store a list oE numbers frequently called, which list is under the control of the subscriber by way of the keypad of the telephone. ~dditionally, in the same or another memory there can be stored information as to the amount of credit remaining on the card, which information is adjustable under control of signals supplied by the telephone.
3~
- 2a -In accordance with an aspect of the invention there is provided a card calling telephone system including a calllng card and a telephone in which the calling card is to be inserted for making calls characterized in that the calling card comprises photovoltaic means adapted to be illuminated with light from said telephone for powering the card, photosensitive means adapted to be illuminated with optical pulses from said telephone for transEerring signal informa-tion fxom the telephone to the card, optical means for providing optical pulses for transferring signal informa-tion from the card to the telephone, and circuit means powered by the photovoltaic means for processing signal information from the photosensitive means and developing signal in:Eormation for the optical means, and the telephone comprises means for illuminating the photo-voltaic means with light, means for illuminating the photo-sensitive means with optical pulses including signal information, photosensitive means adapted to be illuminated by the optical pulses Erom the optical means in the card, and circuit means for processing signal information from the photosenstive means in the telephone and developing signal information for transfer by the optical means in the telephone.
?~:
~23~3~i Brief Descriptio,n of the Drawing The lnvention will be discussed in ~ore detail in connection with the accompanyiny drawing in which:
FIGS. 1 and 2 illustrate a card and a telephone, respectively, in which the various functional elements, important to the invention, are shown in block diagram form.
~L~
In FIG. 1, there is shown schematically a credit card of the kind contemplated for the practice of the inven-tion. It comprises a fairly rigid thin plastic sheet 11 on which the various elements would be supported.
Since the card should be of a size convenient for carrying in a wallet, the sheet would be of corresponding size, typically about two inches by three inches. Mounted on one portion of the sheet is the photovoltaic element 12 which typically comprises several silicon photovoltaic cells serially connected, so that when illuminated there is developed a voltage clearly ade~uate to power the circuitry included on the card. Mounted on another portion of the sheet is a display 13, advantageously a liquid crystal display. Its basic function is to provide the optical pulses used to transfer information from the card to the telephone. Advantageously, these pulses are binary for increased reliability. The information transferred can be of a variety of kinds. One kind can be the number being called when such number is developed from a list of numbers stored in a memory on the card. For such applications, it may be desirable to transmit a plurality of binary digits in parallel, for example eight, to represent a pair of numbers, to increase the speed of transfer. For such a case, the display should include eight discrete elements, one for each of the eight possible pulses.
The display advantageously also should be adaptable upon command to display, for the benefit of the subscriber, in numerical form, the amount of credit still unused on the card. Such a command would be an appropriate :~3~
keying of the keypad of the telephone or of a keypad on the card.
Mounted on another portion of the sheet is a nonvolatile electrically programmable and erasable semiconductor memory 14 (E2PROM) in which there can be programmed initially the amount oE credit bought for the card, which amount can be adjusted by subse~uently erasing some of the information in accordance with credit used up in making a call. ~dditionally, there can be provision for restoring credit when this is desired. The modification of the inEormation in the memory is controlled by optical signals supplied by the telephone to the card. Mounted on another portion of the sheet is another E2PROM memory 15 in which there is stored a group of telephone numbers frequently called, with provision for entering and changing these numbers under control of the subscriber by appropriately keying the keypad of the telephone. Of course, memories 14 and 15 can be integrated into a sin~le memory. Mounted on another portion of the sheet is a microprocessor chip 16 used for controlling the various elements described or achieving the functions desired. Also depicted is a photodiode 17 which is used to collect the light pulses supplied by the telephone to provide control information to the card. Alterna-tively photovoltaic element 12 could be adapted to serve this role, as discussed hereinafter~ Also distributed on the sheet, properly located and interconnected, are any other circuit elements (not shown) needed to effect the desired control functions and not conveniently included in the microprocessor chip 16. The interconnecting wiring needed also has not been shown.
It will, of course, be appreciated that separate chips may be unnecessary for each o the functional elements described and that two or more may be incorporated into a common chip. For example, it should be feasible to incorporate the microprocessor, memory, and photovoltaic as separate portions of a sin~le monolithic silicon chip.
~3~3~
The circui-t elements and wiriny advantageously are covered by a protective covering, transparent as needed to permit the passage of the useful light to and from the photosensitive and display portions.
An important advantage of the system of the invention is the absence of need for any critical direct electrical connection between the card and the telephone Eor the basic functions described. By such absence and by the use only of optical pulses for communication between the card and telephone, the reliability of the system can be greatly increased.
In FIG. 2, there are shown the basic elements needed in the telephone in which the credit card is inserted to e-ffect a credit card call in accordance with the invention. It includes a first light source 21 that would provlde the illumination on the photovoltaic element 12 used to power the card. It may also include a second light source 22 which can be used to supply control pulses to photodiode 17, or alternatively the photovoltaic element 12 if that element is used in a dual role. In this case, the function of light source 22 may be achieved by appropriately modulating the light source 21, in accordance with the desired signal information, and recovering such information by demodulation fro~ the voltage developed by element 12.
The telephone also lncludes photos~nsitive means 33 adapted to recover the optical pulses generated by the display 13 of the card. The photosensitive means should be adapted to complement the display included on the card. For example, if for communicating with the telephone the card is designed to display eight binary digits simultaneously in parallel, the means 23 advantageously comp~ises an array of eight photodiodes, one for each of the light positions of the display.
Additionally, the telephone includes the various control circuits, designated simply by box 24, which would be used in conjunction with elements 21, 22 and 23, and the 3~;
card to achieve the various functions described.
Since it i5 believed well within the skill of a worker in the telephone art to design the appropriate control circuitry, both o~ the telephone and of the card, and since the specific form oE control circuitry employed is not a part oE this invention, no specific form is being shown.
However, the circuits are intended to act in the following fashion.
To initiate a call, the subscriber would first insert the card, of the kind described, in a telephone of the kind described. Typically, such telephones would be located at airports or other locations where credit card calling is prevalent and being encouraged~ The subscriber would then key in an appropriate code on the telephone's ke~pad. This would actuate the telephone and cause it to power the card by appropriatel~ illuminating its photovoltaic source. The telephone would then interrogate the card by appropriate light pulses supplied to the card's photodiode and the card would supply information about itself to the telephone by way of optical pulses generated by its display. This information typically would include the amount of credit remaining on the card and, probably also an identification of the subscriber. Then by manipulating appropriately the keypad, the subscriber could either enter the number to be called directly or else select a number from the list stored in the card's ~emory.
The telephone would then connect the subscriber to the called party and the call would proceed. The telephone would be monitoring the cost of the call continuously. I~
the card's credit approached exhaustion, as an optional feature the telephone might initiate so~e warning signal to the subscriber. At the completion of the call, the telephone would calculate the cost of the call~ and transfer cost information to the card as a series o~
optical pulses which would be recovered by photodiode on the card. The resulting electrical signal would be ~3~3~
processed by the microprocessor on the card and the latter would develop an electrical signal which would be supplied to the mernory on the card to adjust the amount of credit remaining on the cardO Thereafter, the card could be released for removal. Provision can also be made so that, beEore complete release, the subscriber could, by an appropriate keypad entry, arrange to have the amount of the remaining balance shown on the card's display. Various alternatives are available for handling any charges in iO excess of the credit on the card.
Various other functions could obviously be performed by coaction of the card and telephone. For example, for changing numbers stored in the card's memory, an appropriate entry into the telephone's keypad could result in optical pulses to the card to erase numbers previously stored and to substitute new ones~
Background of the Invention The present invention relates to a card telephone calling system and, more particularly, to one in which the calling cards are provided with built-in information to adapt them to specific functions.
In the typical card telephone calling system, information is transferred from the card, usually for control purposes, to the telephone in which the card is inserted, but there is little information transferred from the telephone back to the card because there has not been known a way to do this reliably. This has restricted the functions for which a card may be used.
The present invention relates to a card calling telephone system in which information is transferred both from and to the card.
It would be desirable to use a calling card in the following ways if each could be readily done. It would be desirable if the card would permit a call to be made without the need for any cash transfer at the time but with a minimum need for extraneous record keeping or follow-up billing. This can be accomplished if there is provided a card in which there is built in a certain calling capacity for which the owner has previously paid, and which capacity is automatically reduced by an appropriate amount as the card is used. Moreover, the calling capacity of the card should be readily reinstatable without the need for replacing the card.
Additionally, an ideal calling card system ~ould provide for the rapid-call feature in which -the subscriber stores in the card a group of telephone numbers frequently called from which a particular one can be easily selected for use in making a call automatically. Mor~over, the subscriber should have the ability to change this information at will with a minimum of inconvenience.
While the desirability of these functions has ~ ~3~3~
probably been generally recognized, systems including them are not presently available. The present invention is believed to present a novel system which is capable of such functions involving the bilateral transfer oE
information between the telephone and the card.
the Invention A card calling system in accordance with the present invention is characterized by the use of optical signals both for transferring information from the card to the telephone for transferring information from the telephone back to the card, and for powering the card.
In particular, it includes a card which is provided with photosensitive means adapted to be illuminated with light from the telephone. Such light is used both to power the electronics on the card and to transfer information in the form of optical pulses from the telephone to the card. Additionally, the card includes provision for generating appropriate light pulses when information is to be transferred from the card to the telephone. Conversely, in such a system, the telephone is provided with photosensitive means for receiving the optical pulses generated by the card for transferring information to the telephone and light source means for illuminating the card appropriately when information is being transferred to the card and for powering the card.
The card further includes the necessary electronics including, for example, a nonvolatile semiconductor memory in which is stored the information necessary for the functions expected of it and which can be programmed by information supplied by optical pulses from the telephone. Typically, the memory is adapted to store a list oE numbers frequently called, which list is under the control of the subscriber by way of the keypad of the telephone. ~dditionally, in the same or another memory there can be stored information as to the amount of credit remaining on the card, which information is adjustable under control of signals supplied by the telephone.
3~
- 2a -In accordance with an aspect of the invention there is provided a card calling telephone system including a calllng card and a telephone in which the calling card is to be inserted for making calls characterized in that the calling card comprises photovoltaic means adapted to be illuminated with light from said telephone for powering the card, photosensitive means adapted to be illuminated with optical pulses from said telephone for transEerring signal informa-tion fxom the telephone to the card, optical means for providing optical pulses for transferring signal informa-tion from the card to the telephone, and circuit means powered by the photovoltaic means for processing signal information from the photosensitive means and developing signal in:Eormation for the optical means, and the telephone comprises means for illuminating the photo-voltaic means with light, means for illuminating the photo-sensitive means with optical pulses including signal information, photosensitive means adapted to be illuminated by the optical pulses Erom the optical means in the card, and circuit means for processing signal information from the photosenstive means in the telephone and developing signal information for transfer by the optical means in the telephone.
?~:
~23~3~i Brief Descriptio,n of the Drawing The lnvention will be discussed in ~ore detail in connection with the accompanyiny drawing in which:
FIGS. 1 and 2 illustrate a card and a telephone, respectively, in which the various functional elements, important to the invention, are shown in block diagram form.
~L~
In FIG. 1, there is shown schematically a credit card of the kind contemplated for the practice of the inven-tion. It comprises a fairly rigid thin plastic sheet 11 on which the various elements would be supported.
Since the card should be of a size convenient for carrying in a wallet, the sheet would be of corresponding size, typically about two inches by three inches. Mounted on one portion of the sheet is the photovoltaic element 12 which typically comprises several silicon photovoltaic cells serially connected, so that when illuminated there is developed a voltage clearly ade~uate to power the circuitry included on the card. Mounted on another portion of the sheet is a display 13, advantageously a liquid crystal display. Its basic function is to provide the optical pulses used to transfer information from the card to the telephone. Advantageously, these pulses are binary for increased reliability. The information transferred can be of a variety of kinds. One kind can be the number being called when such number is developed from a list of numbers stored in a memory on the card. For such applications, it may be desirable to transmit a plurality of binary digits in parallel, for example eight, to represent a pair of numbers, to increase the speed of transfer. For such a case, the display should include eight discrete elements, one for each of the eight possible pulses.
The display advantageously also should be adaptable upon command to display, for the benefit of the subscriber, in numerical form, the amount of credit still unused on the card. Such a command would be an appropriate :~3~
keying of the keypad of the telephone or of a keypad on the card.
Mounted on another portion of the sheet is a nonvolatile electrically programmable and erasable semiconductor memory 14 (E2PROM) in which there can be programmed initially the amount oE credit bought for the card, which amount can be adjusted by subse~uently erasing some of the information in accordance with credit used up in making a call. ~dditionally, there can be provision for restoring credit when this is desired. The modification of the inEormation in the memory is controlled by optical signals supplied by the telephone to the card. Mounted on another portion of the sheet is another E2PROM memory 15 in which there is stored a group of telephone numbers frequently called, with provision for entering and changing these numbers under control of the subscriber by appropriately keying the keypad of the telephone. Of course, memories 14 and 15 can be integrated into a sin~le memory. Mounted on another portion of the sheet is a microprocessor chip 16 used for controlling the various elements described or achieving the functions desired. Also depicted is a photodiode 17 which is used to collect the light pulses supplied by the telephone to provide control information to the card. Alterna-tively photovoltaic element 12 could be adapted to serve this role, as discussed hereinafter~ Also distributed on the sheet, properly located and interconnected, are any other circuit elements (not shown) needed to effect the desired control functions and not conveniently included in the microprocessor chip 16. The interconnecting wiring needed also has not been shown.
It will, of course, be appreciated that separate chips may be unnecessary for each o the functional elements described and that two or more may be incorporated into a common chip. For example, it should be feasible to incorporate the microprocessor, memory, and photovoltaic as separate portions of a sin~le monolithic silicon chip.
~3~3~
The circui-t elements and wiriny advantageously are covered by a protective covering, transparent as needed to permit the passage of the useful light to and from the photosensitive and display portions.
An important advantage of the system of the invention is the absence of need for any critical direct electrical connection between the card and the telephone Eor the basic functions described. By such absence and by the use only of optical pulses for communication between the card and telephone, the reliability of the system can be greatly increased.
In FIG. 2, there are shown the basic elements needed in the telephone in which the credit card is inserted to e-ffect a credit card call in accordance with the invention. It includes a first light source 21 that would provlde the illumination on the photovoltaic element 12 used to power the card. It may also include a second light source 22 which can be used to supply control pulses to photodiode 17, or alternatively the photovoltaic element 12 if that element is used in a dual role. In this case, the function of light source 22 may be achieved by appropriately modulating the light source 21, in accordance with the desired signal information, and recovering such information by demodulation fro~ the voltage developed by element 12.
The telephone also lncludes photos~nsitive means 33 adapted to recover the optical pulses generated by the display 13 of the card. The photosensitive means should be adapted to complement the display included on the card. For example, if for communicating with the telephone the card is designed to display eight binary digits simultaneously in parallel, the means 23 advantageously comp~ises an array of eight photodiodes, one for each of the light positions of the display.
Additionally, the telephone includes the various control circuits, designated simply by box 24, which would be used in conjunction with elements 21, 22 and 23, and the 3~;
card to achieve the various functions described.
Since it i5 believed well within the skill of a worker in the telephone art to design the appropriate control circuitry, both o~ the telephone and of the card, and since the specific form oE control circuitry employed is not a part oE this invention, no specific form is being shown.
However, the circuits are intended to act in the following fashion.
To initiate a call, the subscriber would first insert the card, of the kind described, in a telephone of the kind described. Typically, such telephones would be located at airports or other locations where credit card calling is prevalent and being encouraged~ The subscriber would then key in an appropriate code on the telephone's ke~pad. This would actuate the telephone and cause it to power the card by appropriatel~ illuminating its photovoltaic source. The telephone would then interrogate the card by appropriate light pulses supplied to the card's photodiode and the card would supply information about itself to the telephone by way of optical pulses generated by its display. This information typically would include the amount of credit remaining on the card and, probably also an identification of the subscriber. Then by manipulating appropriately the keypad, the subscriber could either enter the number to be called directly or else select a number from the list stored in the card's ~emory.
The telephone would then connect the subscriber to the called party and the call would proceed. The telephone would be monitoring the cost of the call continuously. I~
the card's credit approached exhaustion, as an optional feature the telephone might initiate so~e warning signal to the subscriber. At the completion of the call, the telephone would calculate the cost of the call~ and transfer cost information to the card as a series o~
optical pulses which would be recovered by photodiode on the card. The resulting electrical signal would be ~3~3~
processed by the microprocessor on the card and the latter would develop an electrical signal which would be supplied to the mernory on the card to adjust the amount of credit remaining on the cardO Thereafter, the card could be released for removal. Provision can also be made so that, beEore complete release, the subscriber could, by an appropriate keypad entry, arrange to have the amount of the remaining balance shown on the card's display. Various alternatives are available for handling any charges in iO excess of the credit on the card.
Various other functions could obviously be performed by coaction of the card and telephone. For example, for changing numbers stored in the card's memory, an appropriate entry into the telephone's keypad could result in optical pulses to the card to erase numbers previously stored and to substitute new ones~
Claims (5)
1. A card calling telephone system including a calling card and a telephone in which the calling card is to be inserted for making calls characterized in that the calling card comprises photovoltaic means adapted to be illuminated with light from said telephone for powering the card, photosensitive means adapted to be illuminated with optical pulses from said telephone for transferring signal information from the telephone to the card, optical means for providing optical pulses for transferring signal information from the card to the telephone, and circuit means powered by the photovoltaic means for processing signal information from the photosensitive means and developing signal information for the optical means, and the telephone comprises means for illuminating the photovoltaic means with light, means for illuminating the photosensitive means with optical pulses including signal information, photosensitive means adapted to be illuminated by the optical pulses from the optical means in the card, and circuit means for processing signal information from the photosensitive means in the telephone and developing signal information for transfer by the optical means in the telephone.
2. A card calling system in accordance with claim 1 in which the photovoltaic means and the photosensitive means in the card comprise common photodiode means.
3. A card calling system in accordance with claim 1 in which the telephone includes a keypad adapted for control of signal information transfers between the card and the telephone.
4. A system in accordance with claim 3 in which the circuit means on the card includes memory means in which there can be stored signals corresponding to lists of numbers frequently called and the keypad on the telephone can be used to select a number from the list.
5. A system in accordance with claim 3 in which the circuit means on the card includes memory means on which there can be stored signals corresponding to the amount of credit remaining on the card, and the card and telephone include cooperating means for adjusting the amount.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US60488084A | 1984-04-27 | 1984-04-27 | |
US604,880 | 1984-04-27 |
Publications (1)
Publication Number | Publication Date |
---|---|
CA1230436A true CA1230436A (en) | 1987-12-15 |
Family
ID=24421427
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA000477381A Expired CA1230436A (en) | 1984-04-27 | 1985-03-25 | Card calling telephone system |
Country Status (1)
Country | Link |
---|---|
CA (1) | CA1230436A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5412253A (en) * | 1992-04-20 | 1995-05-02 | Hough; Wayne E. | IC memory card with non-contact power and data connection |
-
1985
- 1985-03-25 CA CA000477381A patent/CA1230436A/en not_active Expired
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5412253A (en) * | 1992-04-20 | 1995-05-02 | Hough; Wayne E. | IC memory card with non-contact power and data connection |
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Legal Events
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