A matrix display device comprises an array of addressable pixels (10) each
having a display element (20) and a control circuit for controlling the
operation of the display element. The control circuit includes a charge
storage capacitor (36) and a photosensitive device (40) coupled to the
storage capacitor for regulating charge stored on the storage capacitor
(36) in accordance with light falling on the photosensitive device (40).
The control circuit further comprises means for independent voltage
control (42) of a gate terminal of the photosensitive device (40),
preferably a phototransistor. In this way a more efficient and flexible
biasing of the phototransistor is possible. The means preferably comprise
a second row line (42) being connected to the gate terminal of the
photosensitive device (40). This additional line allows also the use of
transistors of the same polarity for this type of pixel circuit, saving
additional process masks (and costs). In addition, it becomes possible to
use the phototransistor as a TFT switch. This dual function
(phototransistor/TFT switch) enables the pixel circuit to provide
additional features; for example duty-cycle techniques for motion blur
compensation.