Nature 497, 95–99 (2013)

The eyes of insects and spiders comprise hundreds or even thousands of individual photodetectors. They are highly sensitive to motion and can achieve a remarkable depth of field. Taking this evolutionary solution as their inspiration, Young Min Song and colleagues have engineered an artificial compound eye that is compatible with modern optoelectronic technology.

Choosing materials for their mechanical resilience, the team fabricated an array of 180 microlenses in an elastomer membrane, setting a silicon photodiode at the focal point of each lens. They then moulded the membrane into a hemisphere with a radius of curvature of 7 mm, without any optical misalignment.

Sensors in digital cameras tend to be flat because planar techniques are common in semiconductor processing. But the method demonstrated by Song et al. offers a scalable and affordable way to construct hemispherical optical components — potentially leading to cameras that have an improved angular field of view and fewer aberrations to off-axis light.