ORALS

SESSION: AdvancedMaterialsWedAM-R10	6th Intl. Symp. on New & Advanced Materials & Technologies for Energy, Environment, Health & Sustainable Development
Wed. 30 Nov. 2022 / Room: Saitong
Session Chairs: Luminita Andronic; Sang-June Choi; Session Monitor: TBA

11:55: [AdvancedMaterialsWedAM02] OS
PHOTOLUMINESCENT FILMS FOR LED DISPLAY LIGHTING SYSTEMS WITH BIOLOGICALLY ADEQUATE RADIATION SPECTRUM
Lyudmila Bikova¹ ; Nina Zhelyabovskaya¹ ; Valentina Lichmanova¹ ; Polina Merkulova¹ ; Vladimir Ulasyuk² ; ¹ELTAN Corp, Fryazino, Russian Federation; ²SRC Biolumen, Fryazino, Russian Federation;
Paper Id: 287 [Abstract]

A number of studies have shown that modern LED light sources have a noticeable negative effect on human health, affecting the retina of the eye. The harm is caused by short-wave blue and violet light, which in the spectrum of such light sources has in some cases an intensity increased up to 30% compared to ordinary incandescent lamps. For example, in [1] summarized data on the sensitivity to the spectral distribution of light perceived by the eye, showing the dependences of acute UV-blue phototoxicity, spectral sensitivity of melanopsin with a maximum at 479-483 nm, and sensitivity to suppression of the generation of melatonin with a maximum at 459-464 nm, more dependent on blue light than visual functions mediated by rods (rhodopsin). In order to overcome this drawback of LED light sources, including those used in display backlight systems, the authors of [2] first proposed and developed the concept of LED light sources with a biologically adequate radiation spectrum (BALEDS) [3]. For the production of BALEDS, a technology has been developed for the production of composite photoluminescent films (PLP) from a suspension of a two-component silicone compound OE 6636 (Dow Corning) and photoluminophores based on aluminum-gallium garnets of rare-earth elements activated by cerium with a composition described by the stoichiometric formula Y3-y-zLuyCezAl5-xGaxO12, where 1.8 <x <2.1, 0≤y≤2.86, 0.12≤z≤0.15. PLP are made by applying a suspension to a polyester film using an automatic applicator, followed by annealing in air for 1 hour at a temperature of 100 °C. The PLP containing the photoluminophore (Y2.79Ce0.12Lu0.09Al3.1Ga1.9O12) and excited by an LED with a maximum radiation at a wavelength of 480 nm is used for LED backlight of the augmented reality area of a LCD for projection on a windshield [4]. This work was carried out with the partial support of the RFBR grant (project No. 20-07-01063_a).

References:
1. M.A. Mainster. Violet and blue light blocking intraocular lenses: photoprotection versus photoreception. British Journal of Ophthalmology, 90, pp. 784-792 (2006).
2. V. Ulasyuk, N. Soschin. Biologically adequate white LED lamps based on rare earth phosphors 4th International Workshop on PHOTOLUMINESCENCE IN RARE EARTHS: PHOTONIC MATERIALS AND DEVICES (PRE'12). Kyoto, Japan, 28-30 March 2012.
3. Ulasyuk V.N. LED white light source with biologically adequate emission spectrum. Patent RU2693632. Published: 03.07.2019 Bul. No. 19.
4. Ulasyuk V.N. Car head-up display. Patent RU2732340. Published: 09/15/2020 Bul. No. 26.

SESSION: AdvancedMaterialsWedPM1-R10	6th Intl. Symp. on New & Advanced Materials & Technologies for Energy, Environment, Health & Sustainable Development
Wed. 30 Nov. 2022 / Room: Saitong
Session Chairs: Daiva Sileikiene; Eduard Akim; Session Monitor: TBA

14:25: [AdvancedMaterialsWedPM106] OS
NANOPHONIC METAMATERIALS FOR PROJECTION MICRODISPLAYS
Lyudmila Bikova¹ ; Nina Zhelyabovskaya¹ ; Vladimir Ulasyuk² ; ¹ELTAN Corp, Fryazino, Russian Federation; ²SRC Biolumen, Fryazino, Russian Federation;
Paper Id: 359 [Abstract]

Modern thermoelectric devices tend to use inexpensive, environmentally friendly and CMOS compatible materials such as silicon. To improve the thermoelectric characteristics of silicon, researchers are trying to reduce its thermal conductivity using various nanostructuring techniques [1]. However, most of these methods are of limited effectiveness because they are expensive and destroy the internal structure of silicon. Considering that the calculated thermal conductivity of a system based on a thin silicon film with nanorods to about 50-60% of its initial thermal conductivity with practically unchanged electrical conductivity [2], it is proposed to use silicon nanophonic metamaterials for solution of the urgent problem of creation projection liquid crystal microdisplays with an active matrix of thin-film transistors for head up displays under direct sunlight. It was investigated in model experiments the possibility of nanophonic metamaterials creation in the form of columnar nanostructures (a periodic set of silicon pillars) on thin poly-silicon films using anisotropic plasma etching through a self-aligned mask, which is a set of gold nanodroplets which is created by vacuum deposition of a thin gold film on a silicon wafer followed by annealing at 500 °C without removal of the samples to air. The films were obtained by vacuum deposition of gold in Auto 500FL vacuum deposition unit at the substrate temperature of 200 ° C in a vacuum of 1.3 MPa [3]. The samples were etched in aqua regia and washed in deionized water. The surface morphology was studied using high-resolution scanning electron microscopes JSM 7500 and Supra 25, as well as using AIST-NT and AV 633 atomic force microscopes. As a result of the analysis of experimental data, it was determined that the optimal surface density of gold nanodroplets with a diameter of 20-50 nm is 2.7-3 * 109 cm-2. The use of the studied method of nanoscale modification of the surface of thin polysilicon films in order to implement the properties of nanophonic metamaterials in TFT fits well into the traditional microelectronic technology and, as it seems, should not have any significant effect on electrical characteristics of TFT, while reducing the heating of the liquid crystal from TFTs in projection microdisplays. This research was financially supported by the RFBR grant (Project № 19-07-00456).

References:
[1] Davis, B. L.; Hussein, M. I. Phys. Rev. Lett. 055505 (2014) 112.
[2] L. Bikova, N. Jelyabovskaya, V. Shukhtin and V. Ulasyuk. Proceedings of the 2019 International Conference on Power, Energy, Environment and Material Science (PEEMS 2019) ISBN: 978-1-60595-669-5.
[3] Bikova L.Yu., Dyatlovskaya G.S., Temiryazeva M.P., Ulasyuk V.N., Shukhtin V.I. Proceedings of the II Scientific and Technical Conference "Materials with specified properties in the transition to a new technological order: chemical technologies" - Moscow: SRC "Kurchatov Institute" - IREA (2020) 73-75.