Liquid-crystal indicator driving system

Claim 2

In an electronic computer which includes signal entry means, means for executing an operation in response to a signal entry and means for controlling the operation of said executing means; the combination of a liquid crystal indicator for displaying an information located in said computer, said liquid crystal indicator having at least one common electrode and a plurality of pattern electrodes opposed to said common electrode between which a liquid crystal material is interposed to carry out a displaying operation by applying a voltage between said common electrode and pattern electrodes; means for selecting said pattern electrodes including independent switch elements each connected in circuit with a different one of said pattern electrodes to control the application of voltage across said common electrode and pattern electrodes in response to application of switching signals to said switch elements, said switch elements being arranged such that said switching signals are retained for a duration following application thereof whereby to maintain application of voltage across said electrodes; and a liquid crystal indicator driving system, comprising means for applying a voltage of one polarity between said common electrode and the opposed pattern electrodes, which have been selected by said selecting means, while said computer is in a display indicating mode of its operation and for applying a voltage of a reverse polarity between said common electrode and the opposed pattern electrodes while said computer is in another mode of its operation.

Claim 3

In an electronic computer which includes signal entry means, means for executing an operation in response to a signal entry and means for controlling the operation of said executing means; a liquid crystal indicator driving apparatus comprising the combination of; a liquid crystal indicator comprising a plurality of indicating units for displaying plural digits of information located in said computer, each of said indicating units having one common electrode and a plurality of pattern electrodes opposed to said common electrode between which a liquid crystal material is interposed for displaying one digit of information; a first junction for commonly connecting said common electrode of each of said indicating units; a second junction for commonly connecting said pattern electrodes of each of said indicating units through first switching elements having respective control terminals for controlling a switching operation thereof; a pattern selection means for selecting said pattern electrodes of each of said indicating units; means for connecting to said pattern selection means said control terminals of said first switching elements, which are commonly connected with the corresponding pattern electrodes of said indicating units, through second switching elements having respective control terminals for controlling a switching operation thereof; a digit selection means for selecting at least one digit to be indicated in said liquid crystal indicator; means for connecting to said digit selection means said control terminals of said second switching elements which are connected to the respective control terminals of said first switching elements and which are commonly connected in each of said indicating units, said first and second switching elements being arranged such that signals applied to the control terminals of the first switching elements are maintained thereon for a duration following application of signals to the control terminals of their associated second switching elements; and means for applying a voltage of one polarity across said first and second junctions when said computer is in one mode of its operation and for applying a voltage of another polarity across said first and second junctions while said computer is in another mode of its operation.

Claim 4

In an electronic computer which includes signal entry means, means for executing an operation in response to a signal entry and means for controlling the operation of said executing means; a liquid crystal indicator driving apparatus comprising the combination of; a liquid crystal indicator comprising a plurality of indicating units for displaying plural digits of information located in said computer, each of said indicating units having one common electrode and a plurality of pattern electrodes opposed to said common electrode between which a liquid crystal material is interposed for displaying one digit of information; a first junction for commonly connecting said common electrode of each of said indicating units; a second junction for commonly connecting said pattern electrodes of each of said indicating units through first switching elements having respective control terminals for controlling a switching operation thereof; a pattern selection means for selecting said pattern electrodes of each of said indicating units; means for connecting to said pattern selection means said control terminals of said first switching elements, which are commonly connected with the corresponding pattern electrodes of said indicating units, through second switching elements having respective control terminals for controlling a switching operation thereof; a digit selection means for selecting at least one digit to be indicated in said liquid crystal indicator; means for connecting to said digit selection means said control terminals of said second switching elements which are connected to the respective control terminals of said first switching elements and which are commonly connected in each of said indicating units, said first and second switching elements being arranged such that signals applied to the control terminals of the first switching elements are maintained thereon for a duration following application of signals to the control terminals of their associated second switching elements; and means for applying a voltage of one polarity across said first and second junctions when said computer is in one mode of its operation and for applying a voltage of another polarity across said first and second junctions while said computer is in another mode of its operation.

Claim 5

A combination according to claim 2, wherein said voltage applying means comprises a voltage supply applying a voltage across said first and second junctions and means for reversing polarities of the voltage applied across said first and second junctions by said voltage supply in response to changes in the operational mode of said computer.

Claim 6

A combination according to claim 2, wherein said voltage applying means comprises a parallel circuit arranged between said first and second junctions, said parallel circuit in turn comprising a first voltage source, a first switch connected in series with said first voltage source, a second voltage source of reversed polarity with respect to said first voltage source and a second switch connected in series with said second voltage source; and means for establishing a voltage from said first voltage source across said parallel circuit by closing said first switch and opening said second switch while said computer is in one mode of its operation and for establishing a voltage of said second voltage source across said parallel circuit by opening said first switch and closing said second switch while said computer is in another mode of its operation.

Claim 7

A combination according to claim 4, wherein said first and second voltage sources have different absolute values of voltage.

Claim 8

A combination according to claim 3, wherein the voltage reversal means comprises a third switching element having a control terminal and disposed between one terminal of said voltage supply and said first junction; a fourth switching element having a control terminal and disposed between said one terminal of said voltage supply and said second junction; a fifth switching element having a control terminal and disposed between the other terminal of said voltage supply and said first junction; a sixth switching element having a control terminal and disposed between the other terminal of said voltage supply and said second junction; means for commonly connecting said control terminals of said third and sixth switching elements; and means for commonly connecting said control terminals of said fourth and fifth switching elements.