Holographic optical elements(HOEs)based on polymer composites have become a research hot spot in recent years for augmented reality(AR)due to the significant improvement of optical performance,dynamic range,ease of pr...Holographic optical elements(HOEs)based on polymer composites have become a research hot spot in recent years for augmented reality(AR)due to the significant improvement of optical performance,dynamic range,ease of processing and high yield rate.Nevertheless,it remains a formidable challenge to obtain a large field of view(FOV)and brightness due to the limited refractive index modulation.Herein,we report an effective method to tackle the challenge by doping an epoxy liquid crystal termed E6M,which enables a large refractive index modulation of 0.050@633 nm and low haze of 5.0%at a doping concentration of 5 wt%.This achievement may be ascribed to the improved molecular ordering of liquid crystals within the holographic polymer composites.The high refractive index modulation can endow transmission-type holographic polymer composites with a high diffraction efficiency of 96.2%at a small thickness of 5μm,which would promise the design of thin and lightweight AR devices.展开更多
Holographic polymer/liquid-crystal composites,which are periodically ordered materials with alternative polymer-rich and liquid-crystal-rich phases, have drawn increasing interest due to their unique capabilities of r...Holographic polymer/liquid-crystal composites,which are periodically ordered materials with alternative polymer-rich and liquid-crystal-rich phases, have drawn increasing interest due to their unique capabilities of reconstructing colored three-dimensional(3 D) images and enabling the electro-optic response. They are formed via photopolymerization induced phase separation upon exposure to laser interference patterns, where a fast photopolymerization is required to facilitate the holographic patterning. Yet, the fast photopolymerization generally leads to depressed phase separation and it remains challenging to boost the holographic performance via kinetics control.Herein, we disclose that the ketyl radical inhibition is able to significantly boost the phase separation and holographic performance by preventing the proliferated diffusion of initiating radicals from the constructive to the destructive regions. Dramatically depressed phase separation is caused when converting the inhibiting ketyl radical to a new initiating radical, indicating the significance of ketyl radical inhibition when designing high performance holographic polymer composites.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.52122316,52073108 and 52233005)the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(No.B21003)。
文摘Holographic optical elements(HOEs)based on polymer composites have become a research hot spot in recent years for augmented reality(AR)due to the significant improvement of optical performance,dynamic range,ease of processing and high yield rate.Nevertheless,it remains a formidable challenge to obtain a large field of view(FOV)and brightness due to the limited refractive index modulation.Herein,we report an effective method to tackle the challenge by doping an epoxy liquid crystal termed E6M,which enables a large refractive index modulation of 0.050@633 nm and low haze of 5.0%at a doping concentration of 5 wt%.This achievement may be ascribed to the improved molecular ordering of liquid crystals within the holographic polymer composites.The high refractive index modulation can endow transmission-type holographic polymer composites with a high diffraction efficiency of 96.2%at a small thickness of 5μm,which would promise the design of thin and lightweight AR devices.
基金financial supports from the National Natural Science Foundation of China (51433002 and 51773073)HUST peak boarding program+1 种基金the National Science Foundation (NSF) of Hubei Scientific Committee (2016CFA001)the Fundamental Research Funds for the Central Universities (2019kfy RCPY089)
文摘Holographic polymer/liquid-crystal composites,which are periodically ordered materials with alternative polymer-rich and liquid-crystal-rich phases, have drawn increasing interest due to their unique capabilities of reconstructing colored three-dimensional(3 D) images and enabling the electro-optic response. They are formed via photopolymerization induced phase separation upon exposure to laser interference patterns, where a fast photopolymerization is required to facilitate the holographic patterning. Yet, the fast photopolymerization generally leads to depressed phase separation and it remains challenging to boost the holographic performance via kinetics control.Herein, we disclose that the ketyl radical inhibition is able to significantly boost the phase separation and holographic performance by preventing the proliferated diffusion of initiating radicals from the constructive to the destructive regions. Dramatically depressed phase separation is caused when converting the inhibiting ketyl radical to a new initiating radical, indicating the significance of ketyl radical inhibition when designing high performance holographic polymer composites.
