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A multilayer film with high reflection wavebands and specific visible appearance has been designed based on principles of photonic crystals and optical interference. The angle and thickness sensitivities of this film, which is fabricated with germanium and zinc selenide, were studied and discussed. This multilayer film possesses a high average reflectance between 3 and 5 μm (92.1%) and 8–14 μm (84.2%) wavebands, thereby contributing to a low emissivity in those wavebands according to Kirchhoff's law of thermodynamics. As a result, IR energy from a hot object covered with this film would be suppressed, and low IR signature is expected to be realized. Chromaticity diagram shows that the chromaticity coordinates of this film is close to those of real green plants, which will make it more difficult to distinguish this film from green plant background. Combining the above features, this photonic crystal based film is promising to realize low IR and visible signatures under appropriate conditions. • 1-D PC with specific spectrum was designed and fabricated. • The 1-D PC present a specific color that visibly similar to green plant. • Color blending of this film and green plant background can be realized. • High average reflectance between 3-5 μm and 8–14 μm wavebands. [ABSTRACT FROM AUTHOR]

Infrared stealth requires low emissivity in atmospheric windows. However, low emissivity throughout the infrared band may result in heat accumulation and thus deteriorate the performance of equipment. Photonic crystal films, owing to their selectivity in spectral reflectance, can be used to achieve both infrared stealth and heat dissipation. In this paper, the 5–8 μm band emissive power of different surfaces was calculated first. Then a heat dissipation experiment was carried out to compare the heat dissipation efficiency of a photonic crystal film and a low emissivity film, which showed that the photonic crystal film was cooler thanking to its higher heat emission. The thermal images showed that the film had a better infrared stealth performance than the low emissivity film. This study reveals that photonic crystals are promising to be applied in the infrared stealth field. • This paper studies the effect of increasing the emissivity of the 5-8μm band on the improvement of heat dissipation efficiency by calculation. • The photonic crystal film with higher emissivity in the 5-8μm band exhibits higher heat dissipation efficiency than the low emissivity film. • Compared with the low emissivity film, the photonic crystal film exhibited better infrared stealth performance due to its higher heat dissipation. The results highlight the advantage of photonic crystal films and provide an effective solution for infrared stealth technology. [ABSTRACT FROM AUTHOR]