| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a solution to a problem of a high electricity consumption and a heat generation due to a increase of voltage applied to a light emitter, i.e., to an anode and a cathode of the light emitter, as in a conventional set voltage, it was necessary to set a drain to source voltage V<SB POS="POST">ds</SB>high (V<SB POS="POST">ds</SB>≤V<SB POS="POST">gs</SB>-V<SB POS="POST">Th</SB>+α) of a drive transistor in consideration of a margin of a characteristic change of the light emitter. <P>SOLUTION: In the present invention, a current value variation due to a degradation of a light emitter is fed back and means of control of a power source voltage which sets a set voltage is provided in order to adjust the set voltage. Thus, the set voltage is divided into a saturation region and a linear region (in the vicinity of a critical point)and in particular for an initial setting voltage, it is not required to make account for a voltage margin compensating a degradation. <P>COPYRIGHT: (C)2012,JPO&INPIT |
