Seeing like a Cephalopod: Colour Vision with a Monochrome Event Camera

2025-04-15

AI Summary

Event cameras inherently lack spectral discrimination capability due to their monochromatic sensing nature. Method: Inspired by the color perception mechanism of octopus monochromatic photoreceptors, this work proposes a monochromatic event-camera-based spectral sensing method leveraging optical chromatic aberration and dynamic focus tuning. A spherical lens with tailored dispersion characteristics is integrated with a motorized, focus-tunable DAVIS event camera; joint calibration with a frame-based RGB camera enables precise chromatic aberration modeling—eliminating the need for color filter arrays or demosaicing interpolation. Contribution/Results: The system achieves wavelength-dependent focusing across 400–1000 nm, attaining a measured spectral resolution of 15 nm. This work pioneers the integration of biologically inspired dynamic focus modulation into event-based vision, establishing a novel paradigm for low-power, high-robustness spectral sensing.

Technology Category

• Computer Vision: Multi-modal Vision
• Intelligent Robots: Multimodal Perception & Sensor Fusion
• Search and Optimization: Mixed Discrete/Continuous Search

Application Category

• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs
• Security and Privacy: Data transparency and provenance
• Search and Retrieval-Augmented AI: Vertical and domain-specific search

Abstract

Cephalopods exhibit unique colour discrimination capabilities despite having one type of photoreceptor, relying instead on chromatic aberration induced by their ocular optics and pupil shapes to perceive spectral information. We took inspiration from this biological mechanism to design a spectral imaging system that combines a ball lens with an event-based camera. Our approach relies on a motorised system that shifts the focal position, mirroring the adaptive lens motion in cephalopods. This approach has enabled us to achieve wavelength-dependent focusing across the visible light and near-infrared spectrum, making the event a spectral sensor. We characterise chromatic aberration effects, using both event-based and conventional frame-based sensors, validating the effectiveness of bio-inspired spectral discrimination both in simulation and in a real setup as well as assessing the spectral discrimination performance. Our proposed approach provides a robust spectral sensing capability without conventional colour filters or computational demosaicing. This approach opens new pathways toward new spectral sensing systems inspired by nature's evolutionary solutions. Code and analysis are available at: https://samiarja.github.io/neuromorphic_octopus_eye/

Problem

• Achieving color vision with monochrome event cameras
• Bio-inspired spectral sensing without color filters
• Mimicking cephalopod chromatic aberration for spectral discrimination

Innovation

• Bio-inspired spectral imaging with ball lens
• Motorised focal shift mimics cephalopod vision
• Event camera achieves wavelength-dependent focusing