EP0237539A1 - Anlage zur steuerung einer matrixanzeigetafel mit integriertem speicher und verfahren zu deren steuerung. - Google Patents

Anlage zur steuerung einer matrixanzeigetafel mit integriertem speicher und verfahren zu deren steuerung.

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Publication number
EP0237539A1
EP0237539A1 EP86905321A EP86905321A EP0237539A1 EP 0237539 A1 EP0237539 A1 EP 0237539A1 EP 86905321 A EP86905321 A EP 86905321A EP 86905321 A EP86905321 A EP 86905321A EP 0237539 A1 EP0237539 A1 EP 0237539A1
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EP
European Patent Office
Prior art keywords
read
write
information
circuits
amplifier
Prior art date
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Granted
Application number
EP86905321A
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English (en)
French (fr)
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EP0237539B1 (de
Inventor
Jean Dijon
Thierry Leroux
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Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
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Commissariat a lEnergie Atomique CEA
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Publication of EP0237539A1 publication Critical patent/EP0237539A1/de
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Classifications

    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/36Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
    • G09G3/3611Control of matrices with row and column drivers
    • G09G3/3618Control of matrices with row and column drivers with automatic refresh of the display panel using sense/write circuits

Definitions

  • the present invention relates to a device for controlling a matrix imager with integrated memory and its control method.
  • the invention applies in particular to any matrix imager with active matrix comprising an electro-optical display material of which an optical property such as an opacity, a refractive index, a transparency, an absorption, etc., can be changed with any excitation.
  • the invention applies particularly well to matrix imagers with liquid crystals without gray level, used for example as converters of electrical information into optical information, for the processing of optical images in real time, for analog display.
  • FIG. 1a represents, diagrammatically, a matrix imager with an active matrix, known and FIG. 1b, the control circuit associated with an elementary image point of this imager.
  • FIG. 1a In FIG. 1a are shown first and second insulating walls 1, 3 facing each other, kept apart and sealed by a seal 2 disposed around their periphery. Between these walls 1, 3 is inserted a display material 4 having an optical property.
  • n parallel row conductors denoted L i and m parallel column conductors, denoted C j , crossed with the row conductors, i and j being integers such as 1 ⁇ i ⁇ n and 1 ⁇ j ⁇ m; the row conductors and the column conductors convey electrical signals suitable for the excitation of the material 4.
  • a switch 5 such as a field effect transistor connected to an electrode E ij and to the conductors L i and C j .
  • the internal face of the other wall 3 is covered with a conductive material serving as a counter electrode 10.
  • This counter electrode is brought to a reference potential.
  • An image point I ij is defined in this imager by the region of overlap of an electrode E ij with the counter electrode 10, the electrode E ij and the counter electrode 10 respectively forming the two armatures of a capacitor whose display material, in particular liquid crystal, interposed between these frames forms the dielectric.
  • the counter-electrode 10 is brought to a reference potential V R whose value is periodically inverted and the conductors lines and the conductors columns convey electrical signals, for example of rectangular shape.
  • FIG. 1b represents in a known manner the electrical diagram of a control circuit associated with an image point I ij , this being represented by a capacitor.
  • a control circuit associated with an image point I ij , this being represented by a capacitor.
  • a field effect transistor 5 connected to one of the armatures of the capacitor corresponding to the electrode E ij ; the other armature of this capacitor corresponding to the counter-electrode is brought to the reference potential V R.
  • This capacitor allows the memorization of information to display at image point I ij .
  • the column electrical signal transmitted to the electrode E ij creates an electric field between the armatures of the capacitor constituted by the electrode E ij and the counter electrode.
  • This field causes a collective orientation of the liquid crystal molecules included between the armatures of the capacitor, when the transmitted signal is higher than a certain voltage, called threshold, corresponding to the minimum value necessary to excite the liquid crystal.
  • document FR-A-2,553,218 describes another type of matrix imager, with active matrix.
  • line conductors l connected by transistors to electrodes distributed in a matrix opposite the column electrodes, said transistors being further connected to a reference potential V R.
  • An image point of this imager is defined by the area of overlap of an electrode with a column electrode, these two electrodes respectively forming the two plates of a capacitor.
  • the electrical diagram of the control circuit associated with an image point of such an imager differs from that shown in FIG. 1b by the position of the capacitor.
  • the capacitor is in this case connected between the column conductor and the transistor, the latter being moreover connected to the corresponding line conductor and to the reference potential V R.
  • a control device comprises, in known manner, an image memory external to the imager connected via interfaces to control means such as a computer, an image controller connected to the image memory external, by means of logic circuits, circuits for processing serial video signals connected to the image controller and circuits for processing video signals connected to these processing circuits.
  • the computer manages the various elements of the control device and transmits the information to be displayed to the external image memory.
  • the image controller scans the information stored in the external image memory.
  • the processing circuits transmit to the signal processing circuits vi deo, developed from the signals provided by the image controller. These processing circuits make it possible to transcribe the video signals from means such as shift registers, into line signals and into column signals. The latter are transmitted respectively to the line conductors and to the column conductors, so as to obtain a point-by-point display of the imager.
  • This control device only allows information to be written to the image points of the imager. To refresh information at an image point, it is rewritten by taking the corresponding information from the external image memory and not from the image point itself. The refresh is carried out every 20 milliseconds and therefore the frequency of the video signal which contains the information to be displayed in series must be fast of the order of 5 MHz. Consequently, the control device must be produced in rapid technology, that is to say in monocrystalline silicon, which has the drawbacks of making its manufacture complex and its high manufacturing cost.
  • control devices whose image memory is integrated into the imager, making it possible to write but also to read and refresh information in image points of the imager.
  • Such a device is for example described in the document GB-A-2 113 444.
  • the subject of the invention is a new control device, the image memory of which is integrated into the imager, making it possible in particular to remedy the aforementioned drawbacks and in particular to be achievable in technology both fast and slow.
  • control device of the invention applies to all matrix imagers, with matrix active, and in particular to those described above.
  • the invention relates to a device for controlling a matrix imager comprising nm image points arranged in a matrix, a first family of n row conductors and a second family of m column conductors carrying signals suitable for excitation of an electrooptical display material, each image point of the imager, formed of a capacitor whose dielectric consists of the display material, being associated with a line conductor, a column conductor and a switch, each image point constituting an imager point memory in which one can write, read and refresh information, characterized in that this control device comprises m read / write circuits each connected to a column conductor for writing, reading and refreshing information at the image points associated with said column conductor, said read / write circuits being grouped into k packets, each packet uet comprising at most l read / write circuits, with m, l and k integers such as 1 ⁇ l ⁇ m and 1 ⁇ k ⁇ m, the read / write circuit packets being connected to a bidirectional data bus of l
  • the control device comprises processing means comprising k processing circuits each connected to a packet of read / write circuits, the read, write and refresh operations performed by the read circuits / write being selected via the processing circuits receiving the control signals and sending selection signals to the read / write circuits.
  • control device comprises a first selection circuit such as a decoder connected at the input to n 'address lines and at the output to the n line conductors with n ⁇ 2 n' , for selecting a single line conductor to that time.
  • a first selection circuit such as a decoder connected at the input to n 'address lines and at the output to the n line conductors with n ⁇ 2 n' , for selecting a single line conductor to that time.
  • control device comprises a second selection circuit such as a decoder connected at the input to k 'address lines and at the output to the k processing circuits with k ⁇ 2 k' to select a single packet of conductors. columns by choosing one processing circuit at a time.
  • a second selection circuit such as a decoder connected at the input to k 'address lines and at the output to the k processing circuits with k ⁇ 2 k' to select a single packet of conductors. columns by choosing one processing circuit at a time.
  • each line of the bidirectional data bus comprises a single conductor capable of conveying information in two opposite directions.
  • each line of the bidirectional data bus comprises a first and a second conductor capable of conveying information respectively in a first and a second direction, said first and second directions being opposite.
  • control device does not use an external image memory, which has the consequence of simplifying its production.
  • display made in several image points at the same time allows a realization in slow technology, that is to say in amorphous silicon.
  • the switch is a transistor.
  • each read / write circuit comprises:
  • writing means comprising, in the direction of information transfer, a first processing circuit and a first amplifier linked together,
  • reading means connected in parallel to the writing means, these reading means comprising, in the direction of information transfer, a second amplifier connected both to a storage device and to a second processing circuit, the storage device being further connected to the first processing circuit to allow the refreshment of the information read and stored.
  • the role of the first processing circuit is to transmit either information from the data bus to the first amplifier, or information from the storage device to the first amplifier, as a function of the selection signals received by this circuit.
  • the role of the second processing circuit is to transmit the information read to the data bus. Furthermore, this circuit optionally makes it possible to adapt the electrical signal corresponding to the information read to an electrical signal of binary type compatible with the logic levels of the external electronics, disposed at the output of the data bus.
  • This second processing circuit comprises for example a window comparator.
  • the first processing circuit of each read / write circuit comprises a pre mier transistor connected to the first amplifier, used to transfer information to be written to this first amplifier, and a second transistor connected on the one hand to the first transistor and to the amplifier and, on the other hand, to the storage device, this second transistor used to transfer information read to refresh (in other words to rewrite) to this first amplifier.
  • the memory device for each read / write circuit comprises a transistor and a capacitor connected together, the transistor being further connected to the second processing circuit and to the second amplifier and, the capacitor being further connected to the first processing circuit.
  • one of the first and second amplifiers of each read / write circuit is an inverting amplifier used to apply an alternating signal to the image points.
  • the invention also relates to a device for controlling a matrix imager comprising nm image points arranged in a matrix, a first family of n row conductors and a second family of m column conductors carrying signals suitable for the excitation of a electrooptical display material, each image point of the imager, formed of a capacitor, the dielectric of which consists of the display material being associated with a line conductor, a column conductor and a switch, each image point constituting a memory point of the imager in which one can write, read and refresh information, characterized in that this control device comprises m read / write circuits con each connected to a column conductor to write, read and refresh information at the image points associated with said column conductor, said read / write circuits being connected to a bidirectional data bus, the read, write and refresh operations performed by the read / write circuits being selected from control signals, each read / write circuit comprising:
  • writing means comprising, in the direction of information transfer, a first processing circuit and a first amplifier linked together,
  • reading means connected in parallel to the writing means, these reading means comprising, in the direction of information transfer, a second amplifier connected both to a storage device and to a second processing circuit, the storage device being further connected to the first processing circuit to allow the refreshment of the information read and stored.
  • the first and second processing circuits of each read / write circuit have the same function as those described above; they therefore preferably include the same elements. The same is true for the other elements of the read / write circuit.
  • this control device comprises processing means connected to the read / write circuits, the read, write and refresh operations performed by the read / write circuits being selected by means of the processing means receiving the control signals and sending selection signals to the read / write circuits.
  • the m read / write circuits are grouped into k packets, each packet comprising at most l read / write circuits, with m, l and k integers such as 1 ⁇ l ⁇ m and 1 ⁇ k ⁇ m, the data bus comprising l lines, the p th read / write circuit of a packet being connected to the p th line of said bus with p integer such that 1 ⁇ p ⁇ l.
  • the device according to the invention comprises in this case, processing means comprising k processing circuits each connected to a packet of read / write circuits, the read, write and refresh operations performed by the read / write circuits being selected via the processing circuits receiving the control signals and sending selection signals to the read / write circuits.
  • this control device comprises a first selection circuit connected at the input to n 'address lines and at the output to the n line conductors, with n ⁇ 2 n' , for selecting only one line conductor at a time.
  • this control device advantageously comprises a second selection circuit connected at the input to address lines and at the output to the processing means for selecting at least one column conductor at a time.
  • this second selection circuit makes it possible to select one packet of column conductors at a time and, if not, it selects only one column conductor at a time.
  • the invention also relates to a method for controlling a device according to the invention, characterized in that to read information at an image point of the imager by transmitting it from the image point to data bus via the read / write circuit corresponding to this image point or to write information at this image point by transmitting it in the opposite direction, both the row conductor and the column conductor corresponding to this point are selected image and to read information at an image point of the imager by transmitting it from the image point to the corresponding read / write circuit or to refresh information at this image point by transmitting it in the opposite direction, at least the line conductor is selected corresponding to this image point, these read, write and refresh operations being selected from the control signals.
  • FIGS. 1a and 1b already described, show diagrammatically, respectively, a matrix imager with active matrix of known type and the electrical diagram of the control circuit of an image point of this imager,
  • FIG. 2 represents a block diagram of an example of a control device according to the invention of a matrix imager
  • FIG. 3 shows an example of a read / write circuit according to the invention of an image point of the imager, said circuit being associated with the control circuit of this image point
  • Figure 4a represents an example timing diagram of signals applied to a row conductor and to a column conductor and the resulting signal applied at the corresponding image point, during a writing operation according to the invention
  • FIG. 4b represents a timing diagram of example signals applied to a row conductor, to a column conductor and at the corresponding image point, during an operation of reading according to the invention
  • FIG. 5 shows an example of a processing circuit of the control device according to the invention.
  • FIG. 2 shows a matrix imager 9 comprising nm elementary image points. Each image point is associated with a line conductor L i , with a column conductor C j , with i and j integers such as 1 ⁇ i ⁇ n and 1 ⁇ j ⁇ m, and with a switch such as a transistor with effect of field.
  • This imager is for example of the same type as those described above.
  • each assembly constituted by an image point and the switch associated with this image point bears the reference 7. Furthermore, for simplicity, the reference potential V R has not been shown.
  • the control device shown in FIG. 2 comprises a first selection circuit 13 such as a decoder connected to n 'address lines 14 and to the n line conductors, denoted L i , with n ⁇ 2 n' .
  • the m column conductors, denoted C j are grouped for example into k packets of l column conductors each, each column conductor C. being connected to a read / write circuit 15.
  • the m column conductors and their corresponding read / write circuits 15 are grouped into k packets of l column conductors and l circuits 15, by means of processing means comprising processing circuits 17, one processing circuit 17 per packet of the column conductors and of the read / write circuits 15. There is therefore k processing circuits 17 in this control device.
  • Each read / write circuit 15 of a packet is connected to the processing circuit 17 corresponding to this packet by a bus 12. Furthermore, each read / write circuit 15 of a packet is connected to a line of a bus 21 of bidirectional data of l lines, the p th read / write circuit of a packet being connected to the p th line of bus 21, with p integer such that 1 ⁇ p ⁇ l. Each read / write circuit is connected to the corresponding line of the bus 21, by a bidirectional conductor 16 or by two conductors capable of conveying information in opposite directions from one another. In the rest of the text, we will take the particular example of a bidirectional conductor 16.
  • Each line of the bidirectional bus 21 comprises a single conductor capable of conveying information in two opposite directions or else a first and a second conductor capable of conveying information respectively in a first and a second direction, the first and second directions being opposite.
  • Each processing circuit 17 is further connected to control means (not shown) such as a computer by a bus 20 and to a second selection circuit 19 such as a decoder.
  • This second selection circuit 19 is connected at the input to k 'address lines 18 and at the output to the k processing circuits by the conductors 18', with k ⁇ 2 k ' .
  • the first and second selection circuits 13 and 19 are produced from logic gates according to known principles. These circuits are for example of the same type as those described in the document DEA-3 101 987. On the other hand, examples of processing and read / write circuits 15 will be described in more detail, with reference to FIGS. 3 to 5.
  • Each image point I ij of the imager represented smelled by a capacitor, has the capacity to memorize information. All of these capacitors constitute an image memory integrated into the imager, in which information can be written, read and refreshed.
  • Each refresh operation of the information at the image points of the imager is preceded by an operation of reading this information at these image points.
  • These read and refresh operations can be carried out simultaneously on all the image points of a line of points corresponding to a selected line conductor. During these read and refresh operations, the information is conveyed from the image points to the corresponding read / write circuits and vice versa.
  • the read operations at the image points of the imager making it possible to transmit information from the image points to the data bus 21 via the corresponding read / write circuits and the write operations at the image points of the imager making it possible to transmitting information from the data bus 21 to the image points via the corresponding read / write circuits can be carried out independently. Furthermore, these read or write operations can only be carried out at the same time in a limited number of image points corresponding to the image points associated with both a selected column conductor packet and a selected row conductor. It is understood that the read operations making it possible to transmit information from the image points to the bus 21 can be followed by operations for refreshing this information at these image points, since this information is transmitted via the circuits of readind, writing.
  • I i j + l associated with both the row conductor and the selected column conductors can be transferred to bus 21 and information from this bus can be written at these image points, in other words, the information from the p th image point can be transmitted to the p th data line 'of the bus 21 with p integer such that 1 ⁇ P ⁇ l and the information to be written, carried by the p th bus data line can be transmitted to the p th column conductor of the selected packet and displayed in this p th image point.
  • the information read at the other image points associated with the selected row conductor and the unselected column conductors can be rewritten in these image points.
  • each line conductor By periodically selecting each line conductor, it is possible to periodically read and refresh the information contained at the image points of the imager by transmitting the information from the image points to the corresponding read / write circuits, and vice versa; moreover, in the case where column conductors are selected, it is possible to read or write information at the image points corresponding to both the line conductors and the selected column conductors, by transmitting the information from the image points to the data bus or the reverse, through the read / write circuits.
  • a line conductor L i To select a line conductor L i , send, from control means such as a cal culateur (not shown), electrical signals on the n 'address lines 14 at the input of the selection circuit 13. A zero signal corresponds to the binary element "0" and a non-zero signal to the binary element "1 ".
  • the selection circuit 13 will therefore select from the n 'parallel signals of the n' address lines 14, a single line conductor L. from among the n line conductors which are connected to it.
  • the selection circuit 13 therefore sends to the selected line conductor L i an electrical signal such that the resulting potential applied to the transistors 5 connected to this conductor is greater than or equal to the threshold voltage of the transistors 5, and to the other line conductors an electrical signal such that the resulting potential applied to the transistors connected to these conductors is less than this threshold voltage. All the transistors 5 connected to the conductor lig.ne L i selected, will therefore be in the on state, while the other transistors 5 associated with the other line conductors will be blocked.
  • Each processing circuit 17 prepares read, write or refresh selection signals, as a function of the signals from the selection circuit 19 and the control signals (read / write / refresh) from the control means and conveyed by the bus 20. These selection signals are then sent to the read / write circuits 15 which are connected to it by the buses 12.
  • FIG. 3 shows in detail an example of a read / write circuit 15 connected to a control circuit of the same type as that described in FIG. 1b, it being understood, as we have seen previously, that any other control circuit an active matrix matrix imager can be used.
  • a read / write circuit 15 comprises, in the direction of transfer of information, coming from a line of the data bus 21, from the conductor 16 to the corresponding column conductor C j , during a write operation, a first processing circuit 25 connected to an amplifier 27.
  • a read / write circuit comprises in parallel, in the direction of information transfer from a column conductor C j to the corresponding conductor 16, during a read operation, an inverting amplifier 29 connected to a second processing circuit 33 and a storage device 31 connected to both the inverting amplifier 29 and to the second processing circuit 33.
  • the storage device 31 is further connected to the first processing circuit 25.
  • the information to be written, read or rewritten at an image point I ij consists of the potential difference applied between the plates of the capacitor corresponding to this image point.
  • the first processing circuit 25 is produced by two transistors 24, 26 connected so as to constitute a switch; the storage device 31 is made by a transistor 30 and a capacitor 32.
  • the second processing circuit 33 is made for example by a window comparator well known to those skilled in the art, formed for example by an amplifier against -reacted or else logic gates and dividing bridges; he can be also produced by any device making it possible, from the information read, to determine the state of the corresponding image point, in other words to transform the information read into an electrical signal of the binary type compatible with the external electronics connected to the bus 21, ( a zero electrical signal corresponds to a non-displayed state and a non-zero electrical signal to a displayed state).
  • the capacitor 32 is connected on the one hand to the transistor 30 and to the transistor 26 and, on the other hand, to ground; in addition, the transistor 30 is connected to both the processing circuit 33 and the amplifier 29, and the transistor 26 is connected to both the transistor 24 and the amplifier 27.
  • the signals for selecting a write operation or an operation for updating information at the image point I ij , and the signals for selecting a read operation at this image point I ij are produced by the circuit 17 associated with the read / write circuit 15.
  • These selection signals are constituted by electrical signals applied to the circuit 15, at E and at 37 for a write operation, at L and at 35 for a read transfer operation the image point information on the bus 21 by the read / write circuit, in R and in 37 for a refresh operation and in L for a read operation transmitting the information from the image point to the read / write circuit and more precisely to the capacitor 32 of the storage device.
  • the signal will be transmitted to the capacitor corresponding to the image point I ij , by this transistor 5.
  • this potential difference will create an electric field which will therefore excite the molecules of the liquid crystal interposed between the armatures of this capacitor.
  • the information displayed at this point I ij therefore depends on the signal transmitted by the line of the bidirectional data bus 21.
  • the transistor 30 of the storage device being in the on state, it therefore transmits to the capacitor 32 the signal read in order to temporarily store the information contained by this signal.
  • the processing circuit 33 also in the on state, will transmit the signal read to the corresponding line of the bidirectional data bus 21 via the conductor 16.
  • the information contained in, the capacitor 32 makes it possible to refresh the corresponding image point, by rewriting this stored information.
  • the transistors 24 and 30 being blocked, the information will therefore pass through the transistor 26 and through the amplifier 27 before be transmitted to the corresponding column conductor C j .
  • the information initially contained in the capacitor I ij in the form of an electrical signal, will be rewritten with reverse polarity due to the signal inversion effected by the inverting amplifier 29.
  • the amplifier 29 has been chosen inverter, but we could just as easily have taken the inverting amplifier 27 and the non-inverting amplifier 29. Each time the information is refreshed, the polarity of the corresponding signal will be reversed; the application of an alternating signal to the capacitor I ij thus makes it possible to extend the life of the display material, such as the liquid crystal, interposed between the frames of this capacitor.
  • the refresh is carried out for example over a period of approximately 20 ms.
  • FIGS. 4a and 4b show examples of excitation signals V L i , V Cj applied respectively to a row conductor L i and to a column conductor C j during a writing operation (FIG. 4a) and during of a reading operation (FIG. 4b) of information at the corresponding image point, and the resulting signals V ij at the image point.
  • the excitation signals shown in this figure are rectangular impulse signals, but other signals such as sinusoidal signals could also have been applied.
  • the signal V L i applied to the line conductor L i is not zero during a time T called line time, equal to the addressing period T divided by the number of line conductors, n, of the device. Outside this line time T L , the signal V L i is zero.
  • the transistors associated with the line conductor L i are therefore in the on state only during the non-zero pulse of the signal V Li , that is to say during a time T L.
  • the transistor 5 associated with the image point I ij corresponding to a row conductor L i and to a column conductor C j being in the on state it transmits the signal V Cj applied to column C j , to capacitor I ij corresponding to the image point.
  • the signal V Cj is not zero, it is established between the armatures of the con densifier a potential difference equal to the signal V Cr. -V R.
  • the resulting signal V ij seen by the liquid crystal therefore has an equal amplitude V Cj -V R.
  • the armatures of the capacitor remain charged, the corresponding image point therefore keeps during this time T the information written during the line time T L , except for charge leaks.
  • a refresh operation consists in writing the information read. It therefore takes place as before, the signals V Cj and V ij will be the same but of opposite polarity to that of the previous period.
  • FIG. 5 represents an example of a processing circuit 17 of a control device according to the invention.
  • This circuit 17 comprises a logic gate 51 such as an AND gate with two inputs and a logic gate 53 such as a NOR gate also with two in very.
  • the two inputs of door 51 are connected respectively by a conductor 45 'to the corresponding conductor 18' of the selection circuit 19 and to the bus 20 by a conductor 41.
  • the two inputs of door 53 are respectively connected to the output of the door 51 and to the bus 20 via a conductor 43.
  • this circuit 17 comprises a conductor 45 connected to the selection circuit 19 via the corresponding conductor 18 'and two conductors 47 and 49 respectively connected to the bus 20.
  • the conductor 45, the door 51, the door 53, the conductor 47 and the conductor 49 are connected respectively at 35, E, R, L and 37 of all the read / write circuits associated with this processing circuit.
  • the signals applied at L and at 37 conveyed by the conductors 47 and 49 do not depend on the output signal from the selection circuit 19; therefore, these signals are identical for all of the read / write circuits of the control device and depend solely on the control signals.
  • control signals conveyed by the conductors 47 and 49 do not undergo electronic processing in the circuit 17 shown in FIG. 5, but of course, this example is not limiting; one could indeed use in circuit 17 other elements to process said signals.
  • the electrical signals sent to conductors 41, 43, 47 and 49 by bus 20 depend on the operations to be validated and the signal conveyed by conductors 45 and 45 'corresponds to a high level when the processing circuit is selected and to a level low otherwise.
  • the conductor 47 To validate an operation for reading the data from the image points to the read / write circuits, the conductor 47 must convey a signal at a high level "1".
  • the conductors 47 and 45 must respectively carry a signal at the high level.
  • the signals conveyed by the conductors 45 ′ and 41 must both be high for the output signal of door 51 is at the high level.
  • the output signal from door 51 must be at the low level as well as the signal conveyed by the conductor 43 so that the output signal from door 53 is at high level.
  • the conductor 49 must convey a signal at a high level.
  • control device according to the invention can be easily integrated into a conventional imager with attached devices.
  • the device according to the invention can be produced in slow technology and in particular in amorphous silicon.
  • control device made with reference to the selection of column conductors per packet is not limiting, in fact, the control device according to the invention also applies to column conductors selected in a unitary manner.
  • the examples of the various circuits described above of the device according to the invention are not limiting. Indeed, other modifications can be made to these circuits without departing from the scope of the invention.
  • the bidirectional data bus 21 could in particular have been connected to the read / write circuits 15 via the processing circuits 17, these circuits 17 would then have transferred the information from the bus 21 to the read / write circuits 15 and vice versa.
  • the selection circuits 13, 19 described in FIG. 2 are not essential for the operation of the device according to the invention, they make it possible to reduce the number of connections.
EP86905321A 1985-09-16 1986-09-15 Anlage zur steuerung einer matrixanzeigetafel mit integriertem speicher und verfahren zu deren steuerung Expired - Lifetime EP0237539B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8513699A FR2587527B1 (fr) 1985-09-16 1985-09-16 Dispositif de commande d'un imageur matriciel a memoire integree et son procede de commande
FR8513699 1985-09-16

Publications (2)

Publication Number Publication Date
EP0237539A1 true EP0237539A1 (de) 1987-09-23
EP0237539B1 EP0237539B1 (de) 1990-11-28

Family

ID=9322938

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86905321A Expired - Lifetime EP0237539B1 (de) 1985-09-16 1986-09-15 Anlage zur steuerung einer matrixanzeigetafel mit integriertem speicher und verfahren zu deren steuerung

Country Status (6)

Country Link
US (1) US4825202A (de)
EP (1) EP0237539B1 (de)
JP (1) JPS63501319A (de)
DE (1) DE3675929D1 (de)
FR (1) FR2587527B1 (de)
WO (1) WO1987001849A1 (de)

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US5287095A (en) * 1988-12-09 1994-02-15 Hitachi, Ltd. Display device and its displaying method
US5266936A (en) * 1989-05-09 1993-11-30 Nec Corporation Driving circuit for liquid crystal display
DE3930259A1 (de) * 1989-09-11 1991-03-21 Thomson Brandt Gmbh Ansteuerschaltung fuer eine fluessigkristallanzeige
JPH03198087A (ja) * 1989-12-27 1991-08-29 Sharp Corp 表示装置の列電極駆動回路
US5751453A (en) * 1991-12-06 1998-05-12 Ncr Corporation Liquid crystal display with pen-input capability
US5610629A (en) * 1991-12-06 1997-03-11 Ncr Corporation Pen input to liquid crystal display
US5521746A (en) * 1993-02-22 1996-05-28 Engle; Craig D. Poppet valve modulator
US6798394B1 (en) * 1994-10-07 2004-09-28 Semiconductor Energy Laboratory Co., Ltd. Active matrix panel

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US4141000A (en) * 1975-02-21 1979-02-20 Data Recording Instrument Company, Ltd. Interactive displays comprising a plurality of individual display elements
GB2010560A (en) * 1977-11-22 1979-06-27 Suwa Seikosha Kk Liquid crystal display arrangements
JPS56104387A (en) * 1980-01-22 1981-08-20 Citizen Watch Co Ltd Display unit
JPS56119192A (en) * 1980-02-25 1981-09-18 Sharp Kk Method of driving liquid crystal matric display unit
GB2113444A (en) * 1982-01-05 1983-08-03 Standard Telephones Cables Ltd Matrix addressed liquid crystal displays
JPS5961818A (ja) * 1982-10-01 1984-04-09 Seiko Epson Corp 液晶表示装置
JPS59147389A (ja) * 1983-02-10 1984-08-23 シャープ株式会社 ドツトマトリツクス表示装置
US4701799A (en) * 1984-03-13 1987-10-20 Sharp Kabushiki Kaisha Image display panel drive
GB8729036D0 (en) * 1987-12-11 1988-01-27 Tweedie W A Vehicle water filling systems

Non-Patent Citations (1)

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See references of WO8701849A1 *

Also Published As

Publication number Publication date
EP0237539B1 (de) 1990-11-28
WO1987001849A1 (fr) 1987-03-26
US4825202A (en) 1989-04-25
JPS63501319A (ja) 1988-05-19
FR2587527B1 (fr) 1990-10-19
FR2587527A1 (fr) 1987-03-20
DE3675929D1 (de) 1991-01-10

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