Light shuttering for waveguide pupil expansion

A light shuttering device comprising:

• a plurality of liquid crystal cells, wherein each liquid crystal cell is operable to switch between a first optical state or a second optical state in response to a respective first or second drive signal, and wherein individual liquid crystal cells take longer to switch from the second optical state to the first optical state than from the first optical state to the second optical state;
• a drive circuit comprising:
• (i) a plurality of switches, wherein each switch is arranged to output the respective first or second drive signal to a respective liquid crystal cell, and (ii) a drive controller arranged to sequentially update the output of each switch during an update cycle;
• and
• wherein the drive circuit is arranged to determine an order in which the switches are sequentially updated during an update cycle based on any changes to the respective drive signals that will be made during the update where the order in which the switches are sequentially updated during an update cycle comprises updating the output of switches that will be changed from the second drive signal to the first drive signal before updating the output of any other switches.