Liquid lenses have many advantages with respect to their classical glass counterparts (size, speed, lifetime…).
Nonetheless, they had a clear disadvantage in the fact that the optical quality degraded when the lenses were in a tilted position (i.e. optical axis other than vertical). Due to its liquid nature, gravity generates a deformation on the lenses introducing optical aberration in form of coma.
The new architecture developed for the iToBoS project solves this issue by the addition of a secondary liquid reservoir that compensates the deformation suffered by the primary membrane. This solution acts passively and in all orientations, as it is produced by the same gravity force that generates the initial deformation. The gravity coma compensation opens the door to many applications in which the liquid lenses could, previously, offer only a limited optical quality. Now the same high performance can be obtained in any configuration.