Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan.
J R Soc Interface. 2011 Jan 6;8(54):56-66. doi: 10.1098/rsif.2010.0253. Epub 2010 Jun 16.
The structural colour of the neon tetra is distinguishable from those of, e.g., butterfly wings and bird feathers, because it can change in response to the light intensity of the surrounding environment. This fact clearly indicates the variability of the colour-producing microstructures. It has been known that an iridophore of the neon tetra contains a few stacks of periodically arranged light-reflecting platelets, which can cause multilayer optical interference phenomena. As a mechanism of the colour variability, the Venetian blind model has been proposed, in which the light-reflecting platelets are assumed to be tilted during colour change, resulting in a variation in the spacing between the platelets. In order to quantitatively evaluate the validity of this model, we have performed a detailed optical study of a single stack of platelets inside an iridophore. In particular, we have prepared a new optical system that can simultaneously measure both the spectrum and direction of the reflected light, which are expected to be closely related to each other in the Venetian blind model. The experimental results and detailed analysis are found to quantitatively verify the model.
霓虹脂鲤的结构色有别于蝴蝶翅膀和鸟类羽毛的颜色，因为它可以根据周围环境光强的变化而改变。这一事实清楚地表明了产生颜色的微观结构的可变性。众所周知，霓虹脂鲤的虹彩细胞包含几叠周期性排列的光反射薄片，这可以引起多层光学干涉现象。作为颜色可变性的一种机制，百叶窗模型已经被提出，其中假设在颜色变化过程中光反射薄片会倾斜，从而导致薄片之间的间距发生变化。为了定量评估该模型的有效性，我们对虹彩细胞内的单个薄片堆栈进行了详细的光学研究。特别是，我们已经制备了一种新的光学系统，可以同时测量反射光的光谱和方向，这在百叶窗模型中预计是密切相关的。实验结果和详细分析被发现可以定量验证该模型。
