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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. 

In this paper, we present the characterization of a new range sensing approach for use in emerging smart contact lens applications. Smart contact lenses offer a promising approach to treating the most common form of vision loss by using a tunable lens to accommodate for focal errors. A range sensor is an integral component of the system because it estimates an object's distance from the user in order to determine the target focal length. We performed an empirical study with custom fabricated coils in a mock eyeball setup to understand the energy-accuracy trade-offs of a burst-mode sensing approach based on transmission and reception of square pulses between the coils. We wirelessly transmitted square pulses between the coils and estimated the range of an object by sensing the received voltages and inferring the angular relationship between the two contacts. We demonstrate a functioning range sensing approach that can be implemented with energy as low as 1.8 nJ per measurement with at least 95% accuracy. 

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. 

By stacking multiple thin, LC filled lenses based on refractive Fresnel geometry, we experimentally demonstrate a fast response, low-power, and low-profile adaptive optical system that is suitable for integration with a smart contact lens system. 

Using high-performance LC (5CB) filled microfabricated refractive Fresnel chambers, we experimentally demonstrate a thin low-profile adaptive optical system with very high analog tunability (15.5 D) that can be integrated with an adaptive smart contact-lens system. 

This article reports the fabrication, characterization, implementation, and microsystem integration of micromachined flexible silicon solar cells to supply electric power to smart contact lenses. Single silicon solar cell shows the open circuit voltage (V oc ) of 0.5 and 0.55 V Under indoor and outdoor lighting conditions, respectively. The V oc enhanced to 1.25 and 1.65 V after making series connections between three cells. The maximum power output of 50 µW and 2.7 mW are recorded under indoor and outdoor lighting conditions. Furthermore, a power management IC is used to boost up the voltage to 3.3 V and efficiently store or use the generated energy. 

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. 

Using high-performance LC (E7) filled microfabricated refractive Fresnel chambers, we experimentally demonstrate a thin low-profile adaptive optical system with high analog tunability (2.1 D) that can be integrated with an adaptive contact-lens system.