| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve reliability by relieving reduction of a current value due to temporal change in a light emitting device employing constant voltage drive. <P>SOLUTION: Channel width W and channel length L of a drive transistor satisfy L/W≥10. A voltage V<SB>GS</SB>between a gate and a source of the drive transistor is held by a capacitive element comprising a gate electrode of the drive transistor, a semiconductor layer of the drive transistor, and a gate insulation film between the gate electrode and the semiconductor layer. A first voltage is applied on the gate electrode of the drive transistor so that the voltage V<SB>GS</SB>between the gate and the source of the drive transistor, a voltage V<SB>DS</SB>between the source and a drain, and a threshold voltage V<SB>TH</SB>satisfy 1 volt≤¾V<SB>DS</SB>¾≤¾V<SB>GS</SB>-V<SB>TH</SB>¾; and applying a second voltage on the other of a drain electrode and a source electrode of the drive transistor. <P>COPYRIGHT: (C)2007,JPO&INPIT |
