Wave study of compound eyes for efficient infrared detection

Abstract

Improving sensitivity in the infrared spectrum is a challenging task. Detecting infrared light over a wide bandwidth and at low power consumption is very important. Novel solutions can be acquired by mimicking biological eyes such as compound eye with many individual lenses inspired from the nature. The nature provides many ingenious approaches of sensing and detecting the surrounding environment. Even though compound eye consists of small optical units, it can detect wide-angle electromagnetic waves and it has high transmission and low reflection loss. Insects have eyes that are superior compared to human eyes (single-aperture eyes) in terms of compactness, robustness, wider field of view, higher sensitivity of light intensity and being cheap vision systems. All these desired properties are accompanied by an important drawback: lower spatial resolution. The first step to investigate the feasibility of bio-inspired optics in photo-detectors is to perform light interaction with the optical system that gather light and detect it. The most common method used in natural vision systems is the ray analysis. Light wave characteristics are not taken into consideration in such analyses, such as the amount of energy at the focal point or photoreceptor site, the losses caused by reflection at the interfaces and absorption cannot be investigated. In this study, we present a bio-inspired optical detection system investigated by wave analysis. We numerically model the wave analysis based on Maxwell equations from the viewpoint of efficient light detection and revealing the light propagation after intercepting the first interface of the eye towards the photoreceptor site.