Design of self-activating light intensity filter based on thermoplasmics and liquid crystals and simulation of thermal effects caused by localized surface plasmons of different metals

Light intensity filters are a new class of optical filters that are needed with the increasing use of lasers in various fields, including medicine and industry. The mechanism of these filters is such that if the light intensity increases beyond a permissible threshold, it is activated and prevents the passage of intense light, which cause casualties in devices and humans. In this report, a new type of these filters is designed based on the heat generated by plasmonic absorption of metal nanoparticles and the use of this heat to disrupt the order of liquid crystal molecules. In addition, the absorption spectra of different metal nanoparticles have been simulated to achieve the appropriate material at each wavelength. Also, the increase in temperature induced in the substrate due to the absorption of nanoparticles is simulated and based on the existing equations, it is ensured that this temperature increase can lead to the rotation of liquid crystal molecules and thus filter the intense incoming light. .