Hostname: page-component-78c5997874-g7gxr Total loading time: 0 Render date: 2024-11-05T08:22:37.715Z Has data issue: false hasContentIssue false
  • English
  • Français

Polymer-Dispersed Liquid Crystals: Boojums at Work

Published online by Cambridge University Press:  29 November 2013

J. William Doane
Get access

Extract

The idea of dispersing micron-size birefringent particles in a polymer to selectively scatter light is not new. In the 1930s Land patented a light polarizing material in which small, oriented solid crystallites were suspended in a clear polymer. The polymer material was selected so that its refractive index matched one of the principal refractive indices of the crystallites while the other did not. The resuit was a light polarizer tha t would pass one component of polarized light but scatter the other component out of the beam path.

This idea was substantially expanded by the introduction of liquid crystals as the birefringent material. The orientation of the particles (in this case droplets), and hence the refractive index match and the scattering, could be controlled by an electric field. Such a material could be used as a light shutter for either unpolarized or polarized light. In the mid-1970s this basic concept was applied by Hilsum, but having no way to disperse droplets of liquid crystals in a polymer, he did the opposite and put optically isotropic solid particles in the birefringent liquid crystal.

Although Hilsum demonstrated the concept, no commercial device was produced, probably because the shutter contrast was limited. Since then several ways have been found to disperse droplets in a polymer: filling the pores of a microfilter; emulsifying the liquid crystal in a water soluble polymer; and using phase separation methods to create a dispersion of droplets in non-aqueous polymer materials.

Type
Complex Materials
Information
MRS Bulletin , Volume 16 , Issue 1 , January 1991 , pp. 22 - 28
Copyright
Copyright © Materials Research Society 1991

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Land, E.H., U.S. Patent 2,123,902, July 19, 1938.CrossRefGoogle Scholar
2.Hilsum, C., U.K. Patent 1,442,360, July 14, 1976.CrossRefGoogle Scholar
3.Craighead, H.G., Cheng, J., and Hackwood, S., Appl. Phys. Lett. 40 (1982) p. 22.CrossRefGoogle Scholar
4.Fergason, James L., SID Digest of Technical Papers 16 (1985) p. 68.Google Scholar
5.Doane, J.W., Vaz, N.A., Wu, B.-G., and Zumer, S., Appl. Phys. Lett. 48 (1986) p. 269.CrossRefGoogle Scholar
6.Doane, J.W., in Liquid Crystals: Applications and Uses, edited by Bahadur, B. (World Scientiftc Publishers, New Jersey, 1990), Chapter 14.Google Scholar
7.Doane, J.W., West, J.L., Whitehead, J.B. Jr., and Fredley, D.S., Soc. for Information Display Digest XXI (1990) p. 224.Google Scholar
8.Dubois-Violette, E. and Parodi, O., J. Phys. (Paris) Colloque C4 (1969) p. 57.Google Scholar
9.Candau, S., LeRoy, P., and Debeauvais, F., Mol. Cryst. Liq. Cryst. 23 (1973) p. 283.CrossRefGoogle Scholar
10.Press, M.J. and Arrot, A.S., Phys. Rev. Lett. 33 (1974) p. 403.CrossRefGoogle Scholar
11.Volovikand, G.E.Lavrentovich, O.D., Zh. Eksp. Teor. Fiz. 85 (1983) p. 1997 [Sov. Phys. JETP 58 (1983) p. 1159].Google Scholar
12.Williams, R.D.J. Phys. A Math. Gen. 19 (1986) p. 3211.CrossRefGoogle Scholar
13.Žumer, S. and Allender, D.W., Bull. Am. Phys. Soc. 31 (1986) p. 691.Google Scholar
14.Drzaic, P., Mol. Cryst. Liq. Cryst. 154 (1988) p. 239.Google Scholar
15.Yang, H., Allender, D.W., and Lee, M.A., Bull. Am. Phys. Soc. 33 (1988) p. 275.Google Scholar
16.Köhler, A.E., Z. Chemie, Leipzig 259 (1988) p. 33.Google Scholar
17.Allender, D.W. and Žumer, S., Proc. Society for Photonic Instrumentation and Engineering 1080 (1989) p. 18.Google Scholar
18.Koval'chuk, A.V., Kurik, M.V., Lavrentovich, O.D., and Sagan, V.V., Zh. Eksp. Teor. Fiz. 94 (1988) p. 350.Google Scholar
19.Erdmann, J., Žumer, S., and Doane, J.W., Phys. Rev. Lett. 64 (1990) p. 1907.CrossRefGoogle Scholar
20.Žumer, S. (to be published).Google Scholar
21.Volovik, G.E., JETP Lett. 28 (1978) p. 59.Google Scholar
22.Wagner, B.G., Ondris-Crawford, R., Erdmann, J.H., Boyko, E., Žumer, S., and Doane, J.W. (to be published).Google Scholar
23.Golemme, A., Zumer, S., Doane, J.W., and Neubert, M.E., Phys. Rev. A 37 (1988) p. 559.CrossRefGoogle Scholar
24.Wu, B.-G., Erdmann, J.H., and Doane, J.W., Liq. Cryst. 15 (1989) p. 1453.CrossRefGoogle Scholar
25.Drzaic, Paul S., Liq. Cryst. 3 (1988) p. 1543.CrossRefGoogle Scholar
26.Crawford, G.P., Vilfan, M., Doane, J.W., and Vilfan, I., Phys. Rev. A (to appear).Google Scholar
27.Cladis, P.E. and Kléman, M., J. de Phys. 33 (1972) p. 591.CrossRefGoogle Scholar
28.Meyer, R.B., Phil. Mag. 27 (1973) p. 405.CrossRefGoogle Scholar
29.Williams, C.E., Cladis, P.E., and Kléman, M., Mol. Cryst. Liq. Cryst. 21 (1973) p. 355.CrossRefGoogle Scholar
30.Vilfan, M., Vilfan, I., and Žumer, S. (private communication).Google Scholar
31.Kaneko, E., Liquid Crystal TV Displays: Principles and Applications of Liquid Crystal Displays (D. Reidel Publ. Co., Boston, 1987).Google Scholar
32.Yaniv, Z., Doane, J.W., West, J.L., and Tamura-Lis, W., Soc. for Information Display Digest XX (1989) p. 572.Google Scholar
33.Kunigita, M., Hirai, Y., Ooi, Y., Niryama, S., Asakawa, T., Masumo, K., Kumai, H., Yuki, M., and Gunjima, T., Soc. for Information Display Digest XII (1990) p. 227.Google Scholar
34.Montgomery, G.P. Jr., in Large-Area Chromogenics: Materials and Devices for Transmittance Control, edited by Lampert, C.M. and Granqvist, G.G. (SPIE, to be published).Google Scholar
35.Ma, Y.D., Wu, B.-G., and Xu, G., SPIE Proc. for the Society of Optical Engineering 1257 (1990) p. 46.CrossRefGoogle Scholar
36.Drzaic, P., Soc. for Information Display Digest XXI (1990) p. 210.Google Scholar
37.West, John L., Mol. Cryst. Liq. Cryst. 157 (1988) p. 427.Google Scholar
38.Smith, G.W. and Vaz, N.A., Liquid Crystals 3 (1988) p. 543.CrossRefGoogle Scholar