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We propose an artificial iris to tackle sensitivity caused by photophobia. This artificial iris is made with a twisted nematic cell sandwiched between two linear polarizers. The light attenuation performance of a commercial TNC was compared with TNCs made for smart contact lenses. 

We report the theory, construction, and testing of a flexible ocular, on-the-eye microsystem used for ultra-low power object distance sensing suitable for smart adaptive contact lenses. The microsystem determines object distance by vergence angle triangulation. Vergence angle is determined from passive measurements of the earth’s magnetic field at each eye. Vergence measurements were performed every 5-degree interval over 35 degrees in total for each eye to accommodate the entire human visual range. Vergence angle measurements had an RMS error of 1.74 degrees and a distance ranging RMS error of 14.04 mm. The energy requirement per magnetic field measurement was estimated to be approximately 2 μJ per eye. 

We demonstrate fabrication of tunable flexible refractive Fresnel liquid-crystal lens using PET for Smart Contact Lens System. We show focus tunability of 1.9D at 1.1V_RMSusing voltage and pulse width modulation lens tuning techniques. 

One of the essential requirements of any flexible substrate electronic system is the availability of reliable, high density, fine pitch interconnects between components. In this work, we demonstrate a high-toughness two-layer (aluminum, N-doped polysilicon) composite wiring scheme. The top aluminum layer carries most of the current while the polysilicon underlayer electrically bridges any cracks present on the top aluminum induced by flexing thus maintaining electrical conductivity even at very high stresses. When composite and Al control wires on a flexible tape were subject to 4000 cycles of bending, we observed that Al control wires fracture at a 2.5 mm radius of curvature but the composite wires maintain electrical conduction with an increased resistance. 

We report a thin film wearable aluminum-air battery that utilizes the flow of a biological fluid (eye tear) as a moving electrolyte. When the eye blinks, the eye-tear fluid comes into contact with two metal electrodes, and it produces spontaneous redox reactions, which generate an electric current when connected to a load. In this paper, we demonstrate that a 5×5 mm2 tear-activated Al-air battery is capable of providing maximum energy of 45 μJ per eyeblinking cycle. Furthermore, we investigate the effect of different air-breathing electrodes, including gold, platinum, and silver, on the battery's performance. Results demonstrate that the battery's maximum voltage and current outputs are 1 V and 220 μA while using Pt as the cathode. The moving biofluid Al-air battery with the Pt cathode charges up a 10 μF capacitor in 10 s. Furthermore, load line analysis shows a maximum deliverable load power density of 64 μW·cm-2 for this device.