Spectral control in the liquid crystal tunable filters

Abstract

A liquid crystal is used as an electro-optical device with the advantages of low voltage driving, low power consumption, and thin flatness by utilizing its refractive index anisotropy (birefringence). In this research, a liquid crystal tunable filter (LCTF) with control of a main peak wavelength λ₀ and a full-width Δλ at half maximum is developed. The device contains two stacking liquid crystal layers with different wavelength dependences of birefringence Δn with their optical axes perpendicular to each other and controlling the light wavenumbers in a complementary manner (S-ECB).

Keywords:

• Electrically controlled birefringence mode
• full-width at half maximum
• light wavenumber
• liquid crystal
• main peak wavelength
• spectral control

Acknowledgments

In conducting this research, we gained valuable advice and cooperation from Emeritus Professor Tatsuo Uchida of Tohoku University, Professor Takahiro Isabunabe of Tohoku University, and Professor Kazuhiro Wakao of National Institute of Technology, Sendai College. We would like to express our sincere gratitude to them.

Disclosure statement

No potential conflict of interest was reported by the author(s).