Closed microfluidic network for strain sensing embedded in a contact lens to monitor intraocular pressure

A wearable device for measuring an intraocular pressure within an eye, the device comprising:

• a contact lens;
• a first closed microfluidic strain sensor integrated into the contact lens, the first closed microfluidic strain sensor comprising:
• a first gas reservoir containing a gas;
• a first liquid reservoir containing a liquid;
• and
• a first sensing channel connecting the first gas reservoir and the first liquid reservoir;
• wherein the first sensing channel contains a first fluid-gas interface between the first gas reservoir and the first fluid reservoir, the first fluid-gas interface moving within the first sensing channel in response to an axial strain exerted on the contact lens;
• and
• wherein an electronic component is absent from the wearable device,
• wherein the wearable device further comprises a second closed microfluidic strain sensor, the second microfluidic strain sensor comprising a second fluid reservoir, a second gas reservoir, and a second sensing channel;
• wherein the second sensing channel contains a second fluid-gas interface between the second gas reservoir and the second fluid reservoir, the second fluid-gas interface moving within the second sensing channel in response to axial strain exerted on the contact lens.