A system comprising: a passive matrix array of actuation devices, first signal lines and second signal lines for providing a drive signal to an actuation device; and a driver arrangement for providing at least two possible signal levels to the first signal lines and at least two possible signal levels to the second signal lines, the signals being provided such that the drive signal received by an actuation device is a combination of one signal level of the first signal lines and one signal of the second signal lines, wherein each actuation device comprises: - an actuation structure comprising a carrier and an electroactive material attached to the carrier for causing bending and/or a change of bending of at least the carrier in response to a driving of the electroactive material; and - a mechanical structure for defining at least a first stable mechanical state and a second stable mechanical state different from the first stable mechanical state of the actuation structure by mechanically constraining the actuation structure in a bent configuration in at least one of the first and second stable mechanical states, wherein upon the driving, the actuation structure can switch from the first stable mechanical state to the second stable mechanical state, wherein only one of the four possible combined signal levels provides a switching from the first stable state to the second stable state of the device, and characterized in that the actuation structure is substantially flat in one of the first and second stable mechanical states when the actuation device is not driven. a passive matrix array of actuation devices, first signal lines and second signal lines for providing a drive signal to an actuation device; and a driver arrangement for providing at least two possible signal levels to the first signal lines and at least two possible signal levels to the second signal lines, the signals being provided such that the drive signal received by an actuation device is a combination of one signal level of the first signal lines and one signal of the second signal lines, wherein each actuation device comprises: - an actuation structure comprising a carrier and an electroactive material attached to the carrier for causing bending and/or a change of bending of at least the carrier in response to a driving of the electroactive material; and - a mechanical structure for defining at least a first stable mechanical state and a second stable mechanical state different from the first stable mechanical state of the actuation structure by mechanically constraining the actuation structure in a bent configuration in at least one of the first and second stable mechanical states, - an actuation structure comprising a carrier and an electroactive material attached to the carrier for causing bending and/or a change of bending of at least the carrier in response to a driving of the electroactive material; and - a mechanical structure for defining at least a first stable mechanical state and a second stable mechanical state different from the first stable mechanical state of the actuation structure by mechanically constraining the actuation structure in a bent configuration in at least one of the first and second stable mechanical states, wherein upon the driving, the actuation structure can switch from the first stable mechanical state to the second stable mechanical state, wherein only one of the four possible combined signal levels provides a switching from the first stable state to the second stable state of the device, and characterized in that the actuation structure is substantially flat in one of the first and second stable mechanical states when the actuation device is not driven. <EOS>