Tunable MEMS etalon device

An imaging device comprising:

• a) a tunable etalon device comprising a front mirror and a back mirror, wherein the back mirror is linked to a plate
• a flexure structure,
• an anchor structure and a frame structure attached to each other by the flexure structure,
• a back stopper structure,
• wherein the front mirror is movable with respect to the back mirror along a height direction (Z),
• wherein, in an initial pre-stressed un-actuated state of the tunable etalon device:
• the front mirror is in physical contact with the back stopper structure,
• wherein a height difference between:
• a position along said height direction (Z) of a section of the anchor structure or of a section of an element linked to the anchor structure, wherein said section is in contact with said plate, and
• a position along said height direction (Z) of a section of the front mirror in contact with the back stopper structure, induces pre-stress of the flexure structure, and wherein the front and back mirrors are separated by a gap having a pre-stressed un-actuated gap size, the tunable etalon device being configured to assume at least one actuated state in which the gap has an actuated gap size gap greater than the pre-stressed un-actuated gap size;
• b) an image sensor;
• and
• c) a controller configured and operable to tune the tunable etalon device and to capture image data through the image sensor.