Reflectance modulation for energy efficient applications

소개

반사방지막과 반사막을 응용한 에너지 효율적 응용

목차

1. Introduction

2. Theory

3. Applications

4. Research

5. References

본문내용

Fig. 2. Energy efficient window system from HR coating.

Theory (@ normal incidence!)
Interference
Transfer matrix method
Anti-reflection (AR)
: Single, double, triple layer
High-reflection (HR)


Theory: Interference


Fig. 5. Constructive and destructive interference.
Fig. 6. Interference in a quarter-wave coating.
Path difference: 2 × film thickness t (at normal incidence)
Reflection phase-shifts
- Low n to high n: Phase-shift by an angle of π (180°)
- High n to low n: No phase-shift
The wavelength in the medium: λn = λ / n
Fig. 4. Light interference from a thin film.



~ The quarter-wave condition
1. Constructive interference: n0 < nf > ns (blue dots)
~> High-reflection at the targeted wavelength
2. Destructive interference: n0 < nf < ns (red dots)
~> Anti-reflection at the targeted wavelength

Theory: Transfer matrix method

Fig. 7. Reflection of a beam from a single layer.
According to the boundary conditions, the tangential components of the resultant electric and magnetic fields are continuous across the interface.
For the electric field at the two interfaces,
For the magnetic field at the two interfaces,

참고자료

· Frank L. Pedrotti, Leno S. Pedrotti, Introduction to optics, 3rd ed., Prentice Hall, 1993.
· Koohee Han, Jung Hyeun Kim, Materials Letters, 65 (2011) 2466-2469.
· Shui-Yang Lien et al., Solar Energy Materials & Solar Cells, 90 (2006) 2710-2719.
· Christopher E. Valdivia et al., Proceedings of SPIE, 7099 (2008) 709915.
· Mei-Ling Kuo et al., Optics Letters, 33 (2008) 2527-2529.
· Weidong Zhou et al., Journal of Applied Physics, 102 (2007) 103105.
· Eun Sik Kwak et al., Advanced Functional Materials, 19 (2009) 1093-1099.
· I-Kang Ding et al., Advanced Energy Materials, 1 (2011) 52-57.
· P. Spinelli et al., Nature Communications, 3 (2012) 692.