Frequency-addressable apparatus and methods for actuation of liquids
US8228657B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 2008 |
| Grant date | Jul 24, 2012 |
| Priority date | — |
| Expiry date | Mar 17, 2031 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01L2400/0427
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Embodiments of the invention are directed to apparatus, methods, and applications involving the actuation of a semi-insulative working fluid by electromechanical forces based on electrowetting-on-dielectric (EWOD) and liquid dielectrophoresis (liquid DEP) mechanisms that are controlled by the frequency, but not the magnitude, of an AC voltage (i.e., ‘frequency-addressable). In the various apparatus embodiments of the invention, a single, frequency-addressable electrode pair includes at least one electrode that has a spatially-varying dielectric coating thickness and thus a spatially-varying electrode gap wherein at least a portion of which a volume of a working fluid can stably reside under no influence of an applied voltage. In an exemplary aspect, a frequency-addressable, bistable apparatus includes at least one wider gap and one narrower gap associated, respectively, with a thicker and a thinner dielectric coating thickness of the electrode(s). The working fluid resides in only one of the at least two gap regions only under the influence of capillary force. A brief burst of AC voltage at a selected high frequency or low frequency will move the liquid from one gap region to anoth…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.