Dynamic Wavelength Adjustment for Eye Tracking Illumination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing eye-tracking systems face challenges in determining gaze direction effectively in varying ambient light conditions due to limitations in infrared illumination power, leading to poor signal-to-noise ratios and potential eye safety issues, especially in bright or dark environments.
Innovation Solution
An eye detection system that dynamically adjusts the wavelength and intensity of infrared lighting based on ambient conditions, switching between 800 nm to 900 nm and wavelengths greater than 1.2 µm, such as 1.5 µm, to optimize gaze recognition while minimizing eye exposure to radiation and energy consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the infrared illumination power is increased to improve gaze direction determination in bright ambient light, then the signal-to-noise ratio improves, but eye safety is compromised due to excessive radiation exposure
Solution Approach 1:
The patent implements dynamic adjustment of illumination wavelength between 800-900 nm and 1.5 μm based on ambient light conditions. The system switches wavelengths dynamically rather than using a fixed wavelength, allowing optimization of signal quality while maintaining eye safety limits. This resolves the contradiction by making the illumination characteristics adaptive to environmental conditions.
Solution Approach 2:
The patent changes the wavelength parameter of the infrared illumination from a fixed value to a variable parameter that can switch between two ranges (800-900 nm and 1.5 μm). This parameter change allows the system to achieve better signal-to-noise ratio in bright light by using 1.5 μm wavelength with higher permitted power, while maintaining eye safety through wavelength-based power regulation.
2Reliability
If the infrared illumination power is increased to improve signal-to-noise ratio in bright ambient light, then gaze tracking reliability improves, but energy consumption increases
Solution Approach 1:
The patent changes the wavelength parameter to optimize energy efficiency. By switching to 1.5 μm wavelength in bright ambient light, the system achieves better signal-to-noise ratio with lower energy consumption compared to increasing power at 800-900 nm wavelength. The wavelength parameter change enables reliable eye tracking while minimizing energy usage.
3Device complexity
If a fixed wavelength of 800-900 nm is used, then the system is simple to implement, but performance deteriorates in bright ambient light due to limited maximum power
Solution Approach 1:
The patent makes the illumination system multi-functional by enabling it to operate at two different wavelength ranges (800-900 nm and 1.5 μm). This allows a single illumination device to serve multiple purposes: maintaining eye safety in various conditions while achieving adequate signal-to-noise ratio in both dark and bright ambient light environments. The added functionality resolves the performance limitation without significantly increasing complexity.
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
This approach enhances eye-tracking accuracy in bright conditions, ensures eye safety by reducing radiation exposure, and conserves energy, particularly in electric vehicles, by dynamically adjusting lighting to match ambient light levels.
Implementation Method 1
a light source for illuminating at least the user's eyes, configured to emit light of a first wavelength at a first power and light of a second wavelength at a second power
Implementation Method 2
the camera tracks the reflection of that light from the eye
Data Source
Figure 1
AI summary
The invention relates to an eye tracking system for determining the viewing direction of a user, comprising: a camera for recording the eyes of the user; a light source for illuminating at least the eyes of the user, which is designed to emit light of a first wavelength having a first power and light of a second wavelength having a second power; wherein the first wavelength is shorter than the second wavelength and wherein the first power is smaller than the second power; wherein the second wavelength is in particular 1.5 µm; electronic computing means; wherein the eye tracking system is designed for the following: detecting that the illumination of the user by light of the first wavelength having the first power is insufficient for a specified quality of determining the viewing direction; in response to the detecting: illuminating the user by light of the second wavelength having the second power using the light source; determining the viewing direction of the user.