Display apparatus and method of driving same
AssigneePioneer Corporation
InventorMasami Tsuchida
Life of this patent
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Abstract
Disclosed is a display apparatus which can improve the characteristics of TFTs used to select and drive self-emissive elements such as OLEDs. The display apparatus has row electrodes, column electrodes, and a driving unit. The self-emissive elements are formed in regions corresponding to intersections of the row electrodes with the column electrodes. Element driving circuits are formed for driving the self-emissive elements. Each of the element driving circuits includes a selection transistor, a capacitor, and a driving transistor. The driving unit applies a reverse bias to a control terminal of the driving transistor in a non-emission period in which the self-emissive element is not supplied with a driving current.
Claims27
A display apparatus comprising row electrodes, column electrodes intersecting said row electrodes, a driving unit for supplying a scanning signal to said row electrodes and supplying data signals to said column electrodes, self-emissive elements respectively formed in regions corresponding to respective intersections of said row electrodes with said column electrodes, and element driving circuits respectively formed in regions corresponding to the respective intersections for driving said self-emissive elements in accordance with the scanning signal and the data signals, each of said element driving circuits including:
- at least one selection transistor having a control terminal connected to said row electrode and having a first and a second controlled terminal, said at least one selection transistor having a conducting channel between said first and second controlled terminals in response to a forward bias applied to said control terminal on receiving the scanning signal;
- a capacitor for accumulating charges which creates a voltage corresponding to the data signal supplied from said driving unit through said first and second controlled terminals of said selection transistor in a period in which said selection transistor has a conducting channel between said first and second controlled terminals;
- and
- a driving transistor having a control terminal connected to one end of said capacitor, and a first and a second controlled terminal, one of said first and second controlled terminals being connected to said self-emissive element, and said driving transistor supplying said self-emissive element with an amount of driving current depending on a forward bias which is applied to said control terminal in response to the voltage created on said capacitor,
- wherein said driving unit applies a reverse bias to the control terminal of said driving transistor in a non-emission period in which the driving current is not applied to said self-emissive element.
A display apparatus comprising row electrodes, column electrodes intersecting said row electrodes, a driving unit for supplying a scanning signal to said row electrodes and supplying data signals to said column electrodes, self-emissive elements respectively formed in regions corresponding to respective intersections of said row electrodes with said column electrodes, and element driving circuits formed in regions corresponding to the respective intersections for driving said self-emissive elements in accordance with the scanning signal and the data signals, each of said element driving circuits including:
- at least one selection transistor having a control terminal connected to said row electrode and having a first and a second controlled terminal, said at least one selection transistor having a conducting channel between said first and second controlled terminals in response to a forward bias applied to said control terminal on receiving the scanning signal;
- a capacitor for accumulating charges which creates a voltage corresponding to the data signal supplied from said driving unit through said first and second controlled terminals of said selection transistor in a period in which said selection transistor has a conducting channel between said first and second controlled terminals;
- and
- a driving transistor having a control terminal connected to one end of said capacitor, and a first and a second controlled terminal, one of said first and second controlled terminals being connected to said self-emissive element, and said driving transistor supplying said self-emissive element with an amount of driving current depending on a forward bias which is applied to said control terminal in response to the voltage created on said capacitor,
- wherein said driving unit applies a reverse bias to the control terminal of said selection transistor in an emission period in which the driving current is applied to said self-emissive element.
A driving method for a display apparatus including row electrodes, column electrodes intersecting said row electrodes, a driving unit for supplying a scanning signal to said row electrodes and supplying data signals to said column electrodes, self-emissive elements respectively formed in regions corresponding to intersections of said row electrodes with said column electrodes, and element driving circuits formed in regions corresponding to the respective intersections for driving said self-emissive elements in accordance with the scanning signal and the data signals,
- wherein each of said element driving circuits includes:
- at least one selection transistor having a control terminal connected to said row electrode, and a first and a second controlled terminal;
- a capacitor;
- and a driving transistor having a control terminal connected to one end of said capacitor and having a first and a second controlled terminal, one of said first and second controlled terminals being connected to said self-emissive element,
- said driving method comprising the steps of:
- (a) supplying said selection transistor with a scanning signal to apply a forward bias to the control terminal of said selection transistor to form a conducting channel between said first and second controlled terminals of said selection transistor;
- (b) supplying a data signal to said capacitor through the first and second controlled terminals of said selection transistor in a period in which said selection transistor has a conducting channel between the first and second controlled terminals, to accumulate charges which creates a voltage corresponding to the data signal on said capacitor;
- (c) supplying said self-emissive element with an amount of driving current depending on a forward bias which is applied to said control terminal of said driving transistor in response to the voltage created on said capacitor;
- and
- (d) applying a reverse bias to the control terminal of said driving transistor in a non-emission period in which said self-emissive element is not supplied with the driving current.
A driving method for a display apparatus including row electrodes, column electrodes intersecting said row electrodes, a driving unit for supplying a scanning signal to said row electrodes and supplying data signals to said column electrodes, self-emissive elements respectively formed in regions corresponding to intersections of said row electrodes with said column electrodes, and element driving circuits formed in regions corresponding to the respective intersections for driving said self-emissive elements in accordance with the scanning signal and the data signals,
- wherein each of said element driving circuits includes:
- at least one selection transistor having a control terminal connected to said row electrode, and a first and a second controlled terminal;
- a capacitor;
- and a driving transistor having a control terminal connected to one end of said capacitor and having a first and a second controlled terminal, one of said first and second controlled terminals being connected to said self-emissive element,
- said driving method comprising the steps of:
- (a) supplying said selection transistor with a scanning signal to apply a forward bias to the control terminal of said selection transistor to form a conducting channel between said first and second controlled terminals of said selection transistor;
- (b) supplying a data signal to said, capacitor through the first and second controlled terminals of said selection transistor in a period in which said selection transistor has a conducting channel between the first and second controlled terminals, to accumulate charges which creates a voltage corresponding to the data signal on said capacitor;
- (c) supplying said self-emissive element with an amount of driving current depending on a forward bias which is applied to said control terminal of said driving transistor in response to the voltage created on said capacitor;
- and
- (d) applying a reverse bias to the control terminal of said selection transistor in an emission period in which said self-emissive element is supplied with the driving current.
Dependencies are inferred from the claim text.