Significant advances have been made to control the iridescence and the selective reflection of left circularly polarised (LCP) light, and transmission of right circularly polarised (RCP) light of solid films prepared from cellulose nanocrystals (CNCs). However the manipulation of the photonic properties of the CNCs films, which reflect both RCP and LCP light is less investigated. Solid films prepare from natural sources as CNCs have advantageous characteristics that are absent in other synthetic structures, such as wide availability and renewability. Here we review and compare recent research activity involving the production and characterization of photonic band gap structures resulting from an anisotropic layer inserted between two cholesteric layers with different helical pitches but the same handedness. We make connections between systems existing in Nature and synthetic ones with the hope of advancing in the production and manipulation of CNCs-based photonic structures.

在控制由纤维素纳米晶体（CNC）制备的固体膜的虹彩和左圆偏振（LCP）光的选择性反射以及右圆偏振（RCP）光的透射方面，已经取得了重大进展。但是，很少研究反射RCP和LCP光的CNCs薄膜的光子特性的操纵。固态膜是由天然材料制成的，因为CNC具有其他合成结构所不具备的有利特性，例如广泛的可利用性和可更新性。在这里，我们审查和比较涉及光子带隙结构的产生和表征的最新研究活动，该光子带隙结构是由插入在具有不同螺旋间距但具有相同螺旋性的两个胆甾醇层之间的各向异性层产生的。