So, I'm waiting for the battery cap for the detector. While it wings it's way to me, I am concentrating on fibers. Yuqiang spent this afternoon showing me how to pull fibers with the heat rig and then glue the tapers to glass slides.
- Total number of fibers broken: 6
- Number of fibers broken during pulling: 3
- Number of successful tapers: 2
- Number of fibers that caught fire: 1
I don't think these are very encouraging statistics. Jonathan described fiber-pulling as a black art. It seems very unpredictable - the same set of parameters giving you different results each time. After I had broken 3 fibers on the pulling rig, Jonathan suggested reducing the gas flow. This worked perfectly - my last taper was a beauty. Had to break it and throw it away though because tapers are basically poisonous needles.
I've noted down the frequency and time settings for pulling and reversing the rig for next time. I have to pull a shorter taper tomorrow or next day so that the cladding can be glued (or nail-varnished) onto the glass slide.
Gluing the fiber to the slide isn't as horrible as I thought it would be. After clamping the slide to a movable stage, it's purely an eyeball alignment process. After raising the slide up to a fiber mounted across two posts, you finely adjust it until the fiber and slide are within a millimetre of each other. If I wanted to be more accurate, I could use the focus dial of the microscope and see how many rotations are needed to focus the fiber and slide, in turn, at either end. Each rotation is calibrated in terms of distances. But, I'm only fixing a fiber to a slide which doesn't require extreme precision so that detail is unecessary.
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