US 7,405,711 B2Granted

Fixed-pixel display device and cold cathode field electron emission display device

AssigneeSony Corporation

InventorHiroyuki Ikeda

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Abstract

A fixed pixel display device has a construction such that the leading-edge and trailing-edge waveforms of a voltage to be applied to a data electrode can be made steep. The fixed pixel display device is provided with scanning electrodes, data electrodes connected to actuation drivers (50), and light-emitting regions. Each of the actuation drivers (50), includes a switching circuit, an output circuit (51), and a subtraction circuit (52). The switching circuit is equipped with a first switching circuit (53), a second switching circuit (54), and a comparator (55). When a difference (Dm,n-Dm−1,n) between values of data for controlling states of light emission at light-emitting regions, composed by the scanning electrodes in mth and (m−1)th rows, is not smaller than a first reference value [not greater than a second reference value], the first switching circuit (53) [the second switching circuit (54)] is maintained in an ON state to apply a first voltage V1 [a second voltage V2] to the data electrode in an nth column. When the difference is smaller than the first reference value and is greater than the second reference value, the first and second switching circuits, (53) and (54), are maintained in OFF states, respectively.

Claims9

Dependent claims

A fixed pixel display device provided with a multiple number M (M≧2) of stripe-shaped scanning electrodes extending in a first direction and another multiple number N(N≧2) of stripe-shaped data electrodes extending in a second direction different from said first direction such that light-emitting regions formed of overlap regions of said scanning electrodes and said data electrodes are arrayed in a two-dimensional matrix form of M rows×N columns, wherein:

said fixed pixel display device is provided with actuation drivers connected to the respective data electrodes to actuate said data electrodes;
each said actuation driver comprises a switching circuit, an output circuit, and a subtraction circuit;
said switching circuit is provided with:
(A) a first switching circuit for applying a first voltage V1 to the corresponding data electrode,
(B) a second switching circuit for applying a second voltage V2 (V2≠V1) to the corresponding data electrodes, and
(C) a comparator for performing on/off control of said first switching circuit and second switching circuit;
a voltage, outputted from said output circuit on a basis of a value Dm,n (m:
any one of 2, 3, . . . , M;
n:
1, 2, . . . , N) of data for controlling states of light emission at a multiple number N of light-emitting regions formed of the scanning electrode in an mth row, is applied for a fixed duration to the data electrode in an nth column;
and
a value (Dm,n−Dm−1,n), obtained by subtracting at said subtraction circuit a value (Dm−1,n) of data for controlling states of light emission at respective light-emitting regions formed of the scanning electrode in an (m−1)th row from a value (Dm,n) of data for controlling states of light emission at respective light-emitting regions formed of said scanning electrode in said mth row, is inputted as an input value in said comparator, and said input value, inputted in said comparator, is compared with a first reference value and a second reference value at said comparator;
(1) when said input value is not smaller than said first reference value, said first switching circuit is maintained in an ON state for a predetermined duration shorter than said fixed duration on a basis of an output from said comparator such that during said predetermined duration, a first voltage V1 is applied to the data electrode in said nth column;
(2) when said input value is not greater than said second reference value, said second switching circuit is maintained in an ON state for a predetermined duration shorter than said fixed duration on a basis of said output from said comparator such that during said predetermined duration, a second voltage V2 is applied to the data electrode in said nth column;
and
(3) when said input value is smaller than said first reference value but is greater than said second reference value, said first switching circuit and said second switching circuit are maintained in OFF-states, respectively.

13 more elements

A cold cathode field electron emission display device comprising a cathode panel and an anode panel joined together at peripheral edge portions thereof, wherein:

said cathode panel is composed of:
(a) a support,
(b) a multiple number N(N≧2) of stripe-shaped cathode electrodes formed on said support and extending in a first direction,
(c) an insulating layer formed over said support and cathode electrodes,
(d) another multiple number M (M≧2) of stripe-shaped gate electrodes formed on said insulating layer and extending in a second direction different from said first direction, and
(e) electron-emitting regions located at overlap regions of said cathode electrodes and said gate electrodes;
said anode panel is composed of a substrate and phosphor regions and an anode electrode formed on said substrate and arranged corresponding to the electron-emitting regions;
said electron-emitting regions are composed of electron-emitting portions located in bottom parts of holes arranged in said gate electrodes and insulating layer;
said cold cathode field electron emission display device is further provided with:
(f) actuation drivers connected to the respective cathode electrodes to actuate said cathode electrodes;
said actuation drivers each comprises a switching circuit, an output circuit, and a subtraction circuit;
said switching circuit is provided with:
(A) a first switching circuit for applying a first voltage V1 to the corresponding cathode electrode,
(B) a second switching circuit for applying a second voltage V2 (V2≧V1) to the corresponding cathode electrode, and
(C) a comparator for performing on/off control of said first switching circuit and second switching circuit;
a voltage, outputted from said output circuit on a basis of a value Dm,n (m:
any one of 2, 3, . . . , M;
n:
1, 2, . . . , N) of data for controlling states of electron emission at a multiple number N of electron-emitting regions formed of an mth gate electrode, is applied for a fixed duration to an nth cathode electrode;
and
a value (Dm,n−Dm−1,n), obtained by subtracting at said subtraction circuit a value Dm−1,n of data for controlling states of electron emission at the respective electron-emitting regions formed of an (m−1)th gate electrode from a value Dm,n of data for controlling states of electron emission at the respective electron-emitting regions composed by said mth gate electrode, is inputted as an input value in said comparator, and said input value, inputted in said comparator, is compared with a first reference value and a second reference value at said comparator;
(1) when said input value is not smaller than said first reference value, said first switching circuit is maintained in an ON state for a predetermined duration shorter than said fixed duration on a basis of an output from said comparator such that during said predetermined duration, a first voltage V1 is applied to said nth cathode electrode;
(2) when said input value is not greater than said second reference value, said second switching circuit is maintained in an ON state for a predetermined duration shorter than said fixed duration on a basis of said output from said comparator such that during said predetermined duration, a second voltage V2 is applied to the nth cathode electrode;
and
(3) when said input value is smaller than said first reference value but is greater than said second reference value, said first switching circuit and said second switching circuit are maintained in OFF-states, respectively.

22 more elements

A cold cathode field electron emission display device comprising a cathode panel and an anode panel joined together at peripheral edge portions thereof, wherein:

said cathode panel is composed of:
(a) a support,
(b) a multiple number M (M≧2) of stripe-shaped cathode electrodes formed on said support and extending in a first direction,
(c) an insulating layer formed over said support and cathode electrodes,
(d) another multiple number N(N≧2) of stripe-shaped gate electrodes formed on said insulating layer and extending in a second direction different from said first direction, and
(e) electron-emitting regions located at overlap regions of said cathode electrodes and said gate electrodes;
said anode panel is composed of a substrate and phosphor regions and an anode electrode formed on said substrate and arranged corresponding to the electron-emitting regions;
said electron-emitting regions are composed of electron-emitting portions located in bottom parts of holes arranged in said gate electrodes and insulating layer;
said cold cathode field electron emission display device is further provided with:
(f) actuation drivers connected to the respective gate electrodes to actuate said gate electrodes;
said actuation drivers each comprises a switching circuit, an output circuit, and a subtraction circuit;
said switching circuit is provided with:
(A) a first switching circuit for applying a first voltage V1 to the corresponding gate electrode,
(B) a second switching circuit for applying a second voltage V2 (V2<V1) on the corresponding gate electrode, and
(C) a comparator for performing on/off control of said first switching circuit and second switching circuit;
a voltage, outputted from said output circuit on a basis of a value Dm,n (m:
any one of 2, 3, . . . , M;
n:
1, 2, . . . , N) of data for controlling states of electron emission at a multiple number N of electron-emitting regions formed of an mth cathode electrode, is applied for a fixed duration to an nth gate electrode;
and
a value (Dm,n−Dm−1,n), obtained by subtracting at said subtraction circuit a value Dm−1,n of data for controlling states of electron emission at the respective light-emitting regions formed of an (m−1)th cathode electrode from a value Dm,n of data for controlling states of electron emission at the respective electron-emitting regions composed by said mth cathode electrode, is inputted as an input value in said comparator, and said input value, inputted in said comparator, is compared with a first reference value and a second reference value at said comparator;
(1) when said input value is not smaller than said first reference value, said first switching circuit is maintained in an ON state for a predetermined duration shorter than said fixed duration on a basis of an output from said comparator such that during said predetermined duration, a first voltage V1 is applied to said nth gate electrode;
(2) when said input value is not greater than said second reference value, said second switching circuit is maintained in an ON state for a predetermined duration shorter than said fixed duration on a basis of said output from said comparator such that during said predetermined duration, a second voltage V2 is applied to the nth gate electrode;
and
(3) when said input value is smaller than said first reference value but is greater than said second reference value, said first switching circuit and said second switching circuit are maintained in OFF-states, respectively.

22 more elements

Dependencies are inferred from the claim text.

Facts

Application: 10/567,923Filed 13 Aug 2004
Priority: JP 2003-30570629 Aug 2003
Published: US 2006/0262046 A123 Nov 2006
Granted: 29 Jul 2008
Term ends: Not estimatedThe source records don’t support an estimate.

Classification3 codes

G09G 3/22
For presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged…:…
G09G 2310/027
Details of driving circuits: details of drivers for data electrodes, the drivers handling digital grey scale data, e.g. use of D/A converters
G09G
Arrangements or circuits for control of indicating devices using static means to