Eye‐Friendly Reflective Structural Colors with Shortwave Infrared Shielding

Abstract A large number of structural colors proposed concentrate on the optical spectral features in the visible region for improving their color gamut, purity, and brightness. However, there are few attentions on the shortwave infrared region of structural colors, detrimental to human eyes under the long‐term exposure. Here, an asymmetric Fabry–Pérot cavity‐based reflective structural color, composed of planar alternating multilayers of Ti and indium tin oxide (ITO), is proposed and demonstrated, which possesses distinguishing optical features in both visible and shortwave infrared regions. The resonant optical filter at the visible region exhibits a high‐contrast reflective peak due to the constructive interference, generating purer and brighter reflective colors. While displaying vivid colors, the designed structure can also achieve an average light absorption up to 89% across the whole shortwave infrared region to effectively prevent it entering human eyes, benefitting from destructive interference. By controlling the dielectric ITO spacer thickness, full‐color display covering the entire visible region can be realized, even including black color. Consequently, the color gamut exhibits around 135% of standard Red Green Blue (sRGB) and 100% of Adobe RGB. Meanwhile, the proposed structural colors also demonstrate an angle tolerance of 60°, a good thermal stability, and mechanical flexibility.