Living organisms such as fishes¹, cephalopods² and clams³ are cryptically coloured with a wide range of hues and patterns for camouflage, signalling or energy regulation. Despite extensive efforts to create colour-changing materials and devices⁴, it is challenging to achieve pixelated structural coloration with broadband spectral shifts in a compact space. Here, we describe pneumatically inflating thin membranes of main-chain chiral nematic liquid crystalline elastomers that have such properties. By taking advantage of the large elasticity anisotropy and Poisson’s ratio (>0.5) of these materials, we geometrically program the size and the layout of the encapsulated air channels to achieve colour shifting from near-infrared to ultraviolet wavelengths with less than 20% equi-biaxial transverse strain. Each channel can be individually controlled as a colour ‘pixel’ to match with surroundings, whether periodically or irregularly patterned. These soft materials may find uses in distinct applications such as cryptography, adaptive optics and soft robotics.

诸如鱼类¹、头足类动物²和蛤蜊³之类的活生物体被隐蔽地着色，具有用于伪装、信号传递或能量调节的各种色调和图案。尽管在创造变色材料和设备方面付出了巨大的努力⁴，在紧凑的空间中实现具有宽带光谱偏移的像素化结构着色具有挑战性。在这里，我们描述了具有这种特性的主链手性向列液晶弹性体的气动膨胀薄膜。通过利用这些材料的大弹性各向异性和泊松比（> 0.5），我们对封装空气通道的尺寸和布局进行几何编程，以实现从近红外到紫外波长的颜色转换，当量小于 20%双轴横向应变。每个通道都可以作为一个颜色“像素”单独控制，以与周围环境相匹配，无论是周期性的还是不规则的图案。这些软材料可以在不同的应用中找到用途，例如密码学、自适应光学和软机器人。