Holographic Optical Elements: Advantages and Disadvantages for Efficient Lighting, Sun Protection, and Photovoltaic Power Supply of Buildings

2021 ◽  
pp. 10-15
Author(s):  
Alexei K. Solovyov ◽  
Hong-Tham T. Pham
Keyword(s):  
High Efficiency ◽  
Sun Protection ◽  
Hot Water ◽  
Optical Elements ◽  
Advantages And Disadvantages ◽  
Holographic Optical Elements ◽  
Research Organizations ◽  
Energy Environment ◽  
Hot Water Supply

The research of holographic optical elements (HOE) was carried out very intensively in the 1980s and 1990s. They provided great advantages in high-efficiency natural light, while at the same time providing effective sun protection and did not disturb the free view from the windows. The light-directing qualities of these devices made it possible to concentrate direct and scattered solar energy on photovoltaic batteries and solar collectors for hot water supply and solar heating. However, in recent years, research in this area has become less and less frequent without any explanation. The analysis of the research carried out in the framework of one of the latest projects carried out on behalf of the European Commission under the program “Energy, Environment, and Sustainable Development” (EU Contract Number: ENK6-CT‑2000–00327) with the participation of nine research organizations, higher schools, and universities is presented. The role of each of the participants in this interdisciplinary project was to attract experienced researchers in various fields of science and use their knowledge to obtain an objective result.

High Efficiency Holographic Optical Elements For All-Optical Digital Computing

1989 ◽  
Author(s):  
M. R. Taghizadeh ◽  
I. R. Redmond ◽  
B. Robertson ◽  
A. C. Walker ◽  
S. D. Smith
Keyword(s):  
High Efficiency ◽  
Optical Elements ◽  
Holographic Optical Elements ◽  
All Optical

scholarly journals Volume Holographic Optical Elements as Solar Concentrators: An Overview

2019 ◽  
Vol 9 (1) ◽  
pp. 193 ◽  
Author(s):  
Maria Antonietta Ferrara ◽  
Valerio Striano ◽  
Giuseppe Coppola
Keyword(s):  
Tracking System ◽  
Photovoltaic Cell ◽  
Solar Panels ◽  
Optical Elements ◽  
Solar Concentrators ◽  
Advantages And Disadvantages ◽  
Holographic Optical Elements ◽  
Solar Tracking ◽  
Light Concentration ◽  
Physical Principles

Generally, to reduce the area of a photovoltaic cell, which is typically very expensive, solar concentrators based on a set of mirrors or mechanical structures are used. However, such solar concentrators have some drawbacks, as they need a tracking system to track the sun’s position and also they suffer for the overheat due to the concentration of both light and heat on the solar cell. The fundamental advantages of volume holographic optical elements are very appealing for lightweight and cheap solar concentrators applications and can become a valuable asset that can be integrated into solar panels. In this paper, a review of volume holographic-based solar concentrators recorded on different holographic materials is presented. The physical principles and main advantages and disadvantages, such as their cool light concentration, selective wavelength concentrations and the possibility to implement passive solar tracking, are discussed. Different configurations and strategies are illustrated and the state-of-the-art is presented including commercially available systems.

scholarly journals High efficiency, low cost holographic optical elements for ultracold atom trapping

2017 ◽  
Vol 25 (1) ◽  
pp. 296 ◽  
Author(s):  
Sebastien Tempone-Wiltshire ◽  
Shaun Johnstone ◽  
Kristian Helmerson
Keyword(s):  
High Efficiency ◽  
Low Cost ◽  
Ultracold Atom ◽  
Atom Trapping ◽  
Optical Elements ◽  
Holographic Optical Elements

Can trust become a factor of economic growth? Dynamic changes in the level of trust of Russian youth

2020 ◽  
pp. 92-107 ◽  
Author(s):  
A. I. Bakhtigaraeva ◽  
A. A. Stavinskaya
Keyword(s):  
Institutional Environment ◽  
Negative Effects ◽  
Dynamic Changes ◽  
Generalized Trust ◽  
Level Of Education ◽  
Advantages And Disadvantages ◽  
The Future ◽  
Analysis Of Dynamics

The article considers the role of trust in the economy, the mechanisms of its accumulation and the possibility of using it as one of the growth factors in the future. The advantages and disadvantages of measuring the level of generalized trust using two alternative questions — about trusting people in general and trusting strangers — are analyzed. The results of the analysis of dynamics of the level of generalized trust among Russian youth, obtained within the study of the Institute for National Projects in 10 regions of Russia, are presented. It is shown that there are no significant changes in trust in people in general during the study at university. At the same time, the level of trust in strangers falls, which can negatively affect the level of trust in the country as a whole, and as a result have negative effects on the development of the economy in the future. Possible causes of the observed trends and the role of universities are discussed. Also the question about the connection between the level of education and generalized trust in countries with different quality of the institutional environment is raised.

Clustering-Triggered Efficient Room Temperature Phosphorescence from Nonconventional Luminophores

2019 ◽  
Author(s):  
Shuyuan Zheng ◽  
Taiping Hu ◽  
Xin Bin ◽  
Yunzhong Wang ◽  
Yuanping Yi ◽  
...  
Keyword(s):  
Room Temperature ◽  
High Efficiency ◽  
Spin Orbit Coupling ◽  
Design Rationale ◽  
Emission Mechanism ◽  
Room Temperature Phosphorescence ◽  
Electronic Interactions ◽  
Energy Gaps ◽  
Theoretical Results

Pure organic room temperature phosphorescence (RTP) and luminescence from nonconventional luminophores have gained increasing attention. However, it remains challenging to achieve efficient RTP from unorthodox luminophores, on account of the unsophisticated understanding of the emission mechanism. Here we propose a strategy to realize efficient RTP in nonconventional luminophores through incorporation of lone pairs together with clustering and effective electronic interactions. The former promotes spin-orbit coupling and boost the consequent intersystem crossing, whereas the latter narrows energy gaps and stabilizes the triplets, thus synergistically affording remarkable RTP. Experimental and theoretical results of urea and its derivatives verify the design rationale. Remarkably, RTP from thiourea solids with unprecedentedly high efficiency of up to 24.5% is obtained. Further control experiments testify the crucial role of through-space delocalization on the emission. These results would spur the future fabrication of nonconventional phosphors, and moreover should advance understanding of the underlying emission mechanism.<br>

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