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AssigneeTohoku Pioneer Corporation
InventorsTakayoshi Yoshida, Katsuhiro Kanauchi
Estimating the term…
In a drive device for an active type light emitting display panel which can apply a reverse bias voltage to an EL element, in order to be able to compensate deterioration in light-emitting efficiency of the EL element accompanied by applying of the reverse bias voltage and the like, one pixel 10 is composed of a controlling TFT (Tr1), the driving TFT (Tr2), a capacitor C1, and the EL element E1. Switching switches SW1, SW2 mutually enables a supplying state of a forward current to the EL element E1 and an applying state of the reverse bias voltage to be selected. In one control form according to the present invention, when the applying state of the reverse bias voltage shifts to the supplying state of the forward current, by switching one switch first, the anode and cathode of the EL element E1 are made to the same electrical potential to allow electrical charges to be discharged. Thus, charge of the forward current for a parasitic capacitance of the EL element E1 can be performed rapidly, and rising of the lighting operation of the EL element can be advanced.
A drive method for an active type light emitting display panel provided with a light emitting element, a driving TFT which lighting drives the light emitting element, a power supply circuit supplying a current of a forward direction to the light emitting element at a lighting operation time of the light emitting element and a circuit to apply a reverse bias voltage to said light emitting element, wherein
A drive device for an active type light emitting display panel provided with a light emitting element, a driving TFT which lighting drives the light emitting element, a power supply circuit supplying a current of a forward direction to the light emitting element at a lighting operation time of the light emitting element, and a circuit to apply a reverse bias voltage to said light emitting element, wherein there is provided either one of a discharge means to allow electrical discharge of charges accumulated in a parasitic capacitance of the light emitting element and a charge means which performs a charge for the parasitic capacitance of the light emitting element, at the timing at which the applying operation of the reverse bias voltage to the EL element shifts to the supplying operation of the forward current.
Dependencies are inferred from the claim text.