Systematic fabrication of microfiber transducers for testing

posted Jun 15, 2013, 9:38 PM by Sensorica Group   [ updated Jun 17, 2013, 11:43 PM by Tiberius Brastaviceanu ]

Tibi fabricated 5 microfiber transducers to be tested at Phil's. This is in response to the "Why we should explore microfiber transducers" post.

 Optical fiber preparation

We used Infinicor300 glass fiber, 125/62.5, MM from Corning. The fiber was cut in approx. 10cm pieces. A portion was stripped from its jacket closer to one tip, and cleaned with alcohol. The stripped portion was placed within the processing region within the microsplicer (see next row below) to be pulled. The jacket on both sides of the stripped region is necessary for a better grip in the two clamps of the microsplicer.  

 Microfiber pulling

The microsplicer was powered at 9.0V and max current by an adjustable power supply. The current and timer of the microsplicer were both set to 1. During plasma discharge (fuse function) one side of the fiber was manually pulled using one of the two micrometers on the microsplicer. This procedure was repeated a few times, until a microfilament of approx. 2 to 4 mm in length and around 20 microns in diameter was obtained. The transducers are made manually, therefore there is a lot of variability from one to the other, in terms of their diameter profile. We used the microsplicer +/- 5 microns. The tip was rounded by gently melting the fiber at lower voltage. 
connecting the power supply to the splicer
 Fiber tip preparation

The tip was coated with silver using our in-house method. Coating was performed in a drop, without mixing and at room temperature. Two treatments were applied for every fiber. 

After silver coating, the tip was plunged into a clear poxy that is usually used to fuse PMMA fibers together in order to stabilize the silver coating.

Non-conclusive tests were made previously on the microfiber transducer with the LED 850nm Mosquito Prototype I.

microfiber under bending, done in SENSORICA lab, using Prototype I

In this attempt we are trying to test microfibers with the
LED 850nm Mosquito Prototype II.