Manufacture of an optical effector using silicon micro-machining

Abstract

Using a complex micro-machined structure a novel optical-to-fluid pressure converter has been developed. The device offers immunity from electromagnetic interference and the potential for intrinsic safety. The effector, an improved version of a previous device, has been further miniaturized and fully micro-machined from silicon and glass. The device operates when light enters a sealed air-filled cell, formed within a silicon wafer, and is converted to heat by an absorber. The associated rise in temperature increases the pressure inside the cell and forces a diaphragm to move. The diaphragm movement is detected by a change in the back pressure of an impinging jet of fluid; which can be either pneumatic or hydraulic. The response time of the device, of the order of tens of milliseconds, has been further reduced as a result of miniaturization. This paper outlines the manufacturing technique and presents selected experimental test results.

Optical tweezers applied to a microfluidic system

“…[16][17][18][19] In such a microfluidic system, pressure or electroosmotic flow can be used to control the transport of the cells together with their surrounding media. [20][21][22] These shrinking laboratories have allowed smaller and smaller samples to be used. A potential limitation, however, is the difficulty in changing the media around the cells under investigation without also losing control of the cells.…”