| 摘要 |
<p>A video display device comprises
- a plurality of light emitting elements (1-1, 1-2, ..., 1-n) arranged in a matrix having rows and columns;
- a plurality of first current modulators (2-1, 2-2, ..., 2-n), each of which is associated to one of said light emitting elements(1-1, 1-2, ..., 1-n), for drawing a feed current of programmable intensity (ID1, ID2, ..., IDn) for the associated light emitting element (1-1, 1-2, ..., 1-n) from a circuit node (3) associated to each of said columns;
- a current generator (11) controlled by video data representative of desired luminosities (D1, D2, ..., Dn) of said light emitting elements for supplying a first current (IDATA) to said circuit node (3), the intensity of which is representative of a desired luminosity (D1, D2, ..., Dn) of at least one of said light emitting elements (1-1, 1-2, ..., 1-n);
the circuit node (3) having a specific voltage level when the intensity supplied by said current generator (11) is drawn from the current node (3) by the first current modulator (2-1, 2-2, ..., 2-n) associated to said at least one light emitting element(1-1, 1-2, ..., 1-n);
- a second current modulator (10) for supplying a second current (I10) to said circuit node (3);
- a comparator (7) having inputs connected to said circuit node (3) and to a reference terminal which is constantly held at said specific voltage level and an output connected to a control input of said second current modulator (10), whereby the second current (I10) from said second current modulator (10) is controlled so as to yield said specific voltage level at the circuit node (3).
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