Ophthalmic device with built-in self-test circuitry for testing an adjustable lens

Inventors

Lee, Shungneng

Assignees

Verily Life Sciences LLC

Abstract

An ophthalmic device includes an enclosure that is compatible for wearing in or on an eye. An adjustable lens is disposed within the enclosure. Driver circuitry is disposed within the enclosure and coupled to drive the adjustable lens and change its optical power. Built-in-self-test (BIST) circuitry is disposed within the enclosure and coupled to the adjustable lens. The BIST circuitry includes an impedance measurement circuit coupled to selectively measure an impedance of the adjustable lens. A controller is disposed within the enclosure and includes BIST control logic that measures the impedance of the adjustable lens with the impedance measurement circuit to determine a health status of the adjustable lens.

Core Innovation

An ophthalmic device includes an adjustable lens disposed within the ophthalmic device and driven via drive terminals coupled to the adjustable lens to change an optical power of the adjustable lens and provide adjustable accommodation to a user. The ophthalmic device further includes an enclosure housing electronics with an impedance measurement circuit integrated into the ophthalmic device, and the impedance measurement circuit is connected to the adjustable lens via the drive terminals used to change the optical power.

The impedance measurement circuit measures an impedance of the adjustable lens across the drive terminals disposed within the ophthalmic device. The measured impedance is correlated to a health status of the adjustable lens, where the health status includes a determination that the adjustable lens is operational or defective based upon the impedance. The impedance measurement is performed by measuring both a parallel resistance and a parallel capacitance of the adjustable lens.

The correlating of impedance to the health status includes correlating a combination of the parallel resistance and the parallel capacitance measured across the drive terminals to the health status of the adjustable lens. The disclosed approach uses circuit models in which the adjustable lens impedance includes a parallel resistance and capacitance combination with terminal resistances, and it supports comparing measured values and changes over time to expected resistance and expected capacitance ranges. Based on the comparison, the health status is determined as operational or defective, and the disclosed embodiments optionally estimate remaining lifespan of the adjustable lens.

Claims Coverage

The independent claims cover operations and methods for an ophthalmic device that drives an adjustable lens and uses an integrated impedance measurement circuit connected via the same drive terminals used to change optical power. Across the independent claims, the main inventive features total four core elements: driving the adjustable lens, measuring lens impedance across the drive terminals, determining lens health as operational or defective from the impedance, and measuring parallel resistance and parallel capacitance for correlation to health status.

The independent claims require driving the adjustable lens using drive terminals, measuring lens impedance via an impedance measurement circuit integrated within the ophthalmic device and connected through the same drive terminals, and correlating the measured impedance to a health status that classifies the adjustable lens as operational or defective. The claims further require measuring both parallel resistance and parallel capacitance across the drive terminals and correlating the combination of those values to the health status.

Stated Advantages

Documented Applications