Demonstration of an optically actuated ferrule-top device for pressure and humidity sensing

Ferrule-top micro mechanical sensors are an alternative platform for point measurements in critical environments, where standard micro-electro-mechanical systems are prone to failure. To fully benefit from the all-optical character of this design, it is important to demonstrate that the mechanical pieces fabricated on top of the ferruled fiber can be actuated with light. In this paper we propose a convenient, all-optical actuation scheme that can be applied without any additional modification of the sensor design. The scheme relies on the photo thermal effect, which is proven to be sufficient both for inducing significant static bending and for exciting the sensor to resonance. We also demonstrate that this mechanism can be successfully used to implement ferrule-top resonant sensors for humidity and pressure measurements. (C) 2012 Elsevier B.V. All rights reserved.