Capacitive Gaze Tracking for Auto-Accommodation in Contact Lenses
Solution Overview
Problem
Presbyopia, a progressive age-related loss of accommodative strength, affects nearly 1.7 billion people worldwide, leading to increased blur at near distances, and existing solutions fail to effectively address this issue.
Innovation Solution
A smart contact lens with capacitive gaze tracking and accommodation, embedding power supply circuitry, control electronics, a capacitive sensor system, and an accommodation actuator, which detects gaze direction/focal distance and adjusts optical power in real-time to assist with focusing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a smart contact lens with capacitive gaze tracking and accommodation actuator is implemented, then visual clarity for presbyopic individuals is improved through real-time auto-accommodation, but device complexity increases due to embedded power supply circuitry, control electronics, and sensor systems
Solution Approach 1:
The patent combines multiple functional components (capacitive sensor system, power supply circuitry, control electronics, and accommodation actuator) into a single integrated contact lens device. This merging approach enables the lens to perform gaze tracking and auto-accommodation functions simultaneously, improving visual clarity for presbyopic users while consolidating system complexity into one wearable device rather than multiple separate components.
Solution Approach 2:
The contact lens is designed with multi-functionality, serving both as a corrective lens and as a gaze-tracking device with auto-accommodation capabilities. The capacitive sensor system detects gaze direction not only for accommodation control but also potentially for other applications, making the device versatile and justifying the increased complexity through multiple useful functions.
2Reliability
If real-time gaze detection and accommodation adjustment is implemented, then focusing assistance for presbyopia is improved, but power consumption increases due to continuous operation of capacitive sensors and accommodation actuator
Solution Approach 1:
The capacitive sensor system and accommodation actuator operate in a periodic manner rather than continuously. The system detects gaze direction at regular intervals and adjusts accommodation accordingly, allowing the power supply to recharge during intervals between adjustments. This periodic operation reduces overall power consumption while maintaining effective focusing assistance for presbyopic users.
Solution Approach 2:
The power supply circuitry is designed to recharge the battery in advance during periods when accommodation adjustments are not needed. This preliminary charging action ensures that sufficient energy is available for the next accommodation event, reducing the need for high-power continuous operation and extending the device's operational capacity.
3Measurement precision
If capacitive sensor system is embedded in the contact lens, then gaze direction detection precision is improved, but manufacturing complexity increases due to integration of multiple electronic components in a contact lens structure
Solution Approach 1:
The contact lens is divided into distinct functional zones: the capacitive sensor system is positioned in specific regions of the lens to detect gaze direction, while the central optical zone maintains its corrective function. This segmentation allows each component to be optimized for its specific purpose and facilitates manufacturing by enabling separate fabrication of sensor patterns and optical zones before final assembly.
Solution Approach 2:
The contact lens utilizes thin-film technology to integrate the capacitive sensor system and electronic components into the flexible lens structure. The capacitive sensors are fabricated as thin conductive patterns on the lens surface, and the accommodation actuator is implemented as a thin-film device that can be embedded within the lens material. This thin-film approach reduces manufacturing complexity compared to integrating bulky discrete components.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The smart contact lens provides real-time auto-accommodation, enhancing visual clarity for individuals with presbyopia by dynamically adjusting optical power based on detected gaze direction/focal distance, effectively mitigating the effects of age-related focusing difficulties.
Implementation Method 1
the controller is further coupled to monitor the capacitive sensor system to identify gaze direction/focal distance
Implementation Method 2
an accommodation actuator, positioned in a central portion of the enclosure material
Data Source
AI summary
A method of capacitive gaze detection for accommodation includes monitoring at least one capacitance value of a capacitive sensor system disposed within a contact lens. The at least one capacitance value varies in response to changes in a gazing direction of a cornea upon which the contact lens is removeably mounted. The changes in the gazing direction of the cornea are detected in real-time based upon changes in the at least one capacitance value. An accommodation actuator disposed within the contact lens is manipulated to automatically change an optical power of the contact lens in response to detecting changes in the gazing direction.