Generation of high pretilt in photo-aligned polyimides

John L. West; Michinori Nishikawa; Yuri A. Reznikov

doi:10.1117/12.343868

26 March 1999 Generation of high pretilt in photo-aligned polyimides

John L. West, Michinori Nishikawa, Yuri A. Reznikov

Proceedings Volume 3635, Liquid Crystal Materials, Devices, and Applications VII; (1999) https://doi.org/10.1117/12.343868
Event: Electronic Imaging '99, 1999, San Jose, CA, United States

Abstract

Liquid crystals have been shown to align on polarized UV (PUV) exposed polyimide films with the liquid crystal director oriented perpendicular to the polarization direction. Uniform pretilt is produced by a second oblique PUV exposure. We report here the factors controlling liquid crystal alignment and pretilt on photo-exposed polyimide films. We show that the chemistry of the polyimide controls the liquid crystal aligns either parallel or perpendicular to the PUV. Also, the tilt angle of the liquid crystal can be varied continuously between 0 degrees and 90 degrees by adjusting the polyimide chemistry. Our results indicate that the liquid crystal has uniform pretilt with no preferred alignment direction on unexposed polyimide. Normal exposure aligns the director but the pretilt is degenerate, pointing in either the plus or minus direction. Oblique exposure breaks this degeneracy, producing a unique pretilt direction. We show that uniform alignment and pretilt can be produced with a single oblique exposure if the liquid crystal aligns parallel to the polarization direction.

Citation Download Citation

John L. West, Michinori Nishikawa, and Yuri A. Reznikov "Generation of high pretilt in photo-aligned polyimides", Proc. SPIE 3635, Liquid Crystal Materials, Devices, and Applications VII, (26 March 1999); https://doi.org/10.1117/12.343868

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available