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Lorne A Whitehead

Publications and source records attributed to Lorne A Whitehead.

2 recordsLinked to original sources

Modulation of retroreflection by controlled frustration of total internal reflection.

Retroreflective images are useful in outdoor application for which high legibility is required both during the day and in response to vehicular illumination. To date, all variable message retroreflective images have employed mechanical shutters as the switching mechanism. As an alternative, we propose a method for switching the total internal reflection effect used in retroreflectors by means of pneumatic actuation of surface treated polydimethylsiloxane gel. This approach is both effective and compatible with current large-scale manufacturing methods.

Journal Article↗

Electrical modulation of diffractive structures.

We present an experimental demonstration of two new methods for electronically modulating diffractive structures. The first involves the creation of periodic displacement of a liquid-air interface by application of a spatially modulated electric field produced by an array of electrodes. The second method also uses an electrode array but creates a diffraction grating by selectively attracting and repelling electrophoretic particles in a dielectric fluid. Potential areas of application of these techniques include controllable holography and wavelength division multiplexing.

Journal Article↗