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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 18, Iss. 16 — Aug. 2, 2010
  • pp: 16507–16512

Nanoparticle-doped polyimide for controlling the pretilt angle of liquid crystals devices

Shug-June Hwang, Shie-Chang Jeng, and I-Ming Hsieh  »View Author Affiliations

Optics Express, Vol. 18, Issue 16, pp. 16507-16512 (2010)

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The pretilt angles of liquid crystal molecules can be controlled by using conventional polyimide (PI) alignment material doped with different concentrations of Polyhedral Oligomeric Silsequioxanes (POSS) nanoparticles, which have been observed to spontaneously induce vertical alignment. The addition of POSS in the homogenous PI changes the surface energy of the alignment layer and generates a variable pretilt angle. Experimental results demonstrate that the pretilt angle θp is a function of the POSS concentration, and can be tuned continuously over the range of 0°<θp<90°. The polar anchoring energy of POSS/PI alignment layer is almost constant regardless of the POSS concentration. This technique is very simple and is compatible with methods familiar in the current LCD industry.

© 2010 OSA

OCIS Codes
(160.3710) Materials : Liquid crystals
(220.1140) Optical design and fabrication : Alignment
(160.4236) Materials : Nanomaterials

ToC Category:
Optical Devices

Original Manuscript: June 22, 2010
Revised Manuscript: July 13, 2010
Manuscript Accepted: July 14, 2010
Published: July 21, 2010

Shug-June Hwang, Shie-Chang Jeng, and I-Ming Hsieh, "Nanoparticle-doped polyimide for controlling the pretilt angle of liquid crystals devices," Opt. Express 18, 16507-16512 (2010)

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