It is well known that cats have fascinating eyes with various colors,such as green,blue,and brown.In addition,they possess strong night vision ability,which can distinguish things clearly even in a poor light environm...It is well known that cats have fascinating eyes with various colors,such as green,blue,and brown.In addition,they possess strong night vision ability,which can distinguish things clearly even in a poor light environment.These drive us to reveal the secrets behind them.In fact,cats’ eyes can be considered as special lenses(which we would like to mimic by using a Luneburg lens).We make an analysis of the role of photonic crystals behind the lens and demonstrate that the integration of photonic crystals into Luneburg lens can be regarded as a retroreflector and greatly improve the light focusing intensity of the lens in a broad band of frequencies.This wonderful bioinspired phenomenon is expected to design more interesting and serviceable devices by combining photonic crystals with transformation optics.展开更多
基金supported by the National Key Research and Development Program of China (No. 2020YFA0710100)the National Science Foundation of China (Nos. 11874311 and 92050102)the Fundamental Research Funds for the Central Universities (No. 20720200074)
文摘It is well known that cats have fascinating eyes with various colors,such as green,blue,and brown.In addition,they possess strong night vision ability,which can distinguish things clearly even in a poor light environment.These drive us to reveal the secrets behind them.In fact,cats’ eyes can be considered as special lenses(which we would like to mimic by using a Luneburg lens).We make an analysis of the role of photonic crystals behind the lens and demonstrate that the integration of photonic crystals into Luneburg lens can be regarded as a retroreflector and greatly improve the light focusing intensity of the lens in a broad band of frequencies.This wonderful bioinspired phenomenon is expected to design more interesting and serviceable devices by combining photonic crystals with transformation optics.
