A coherent fiberoptic bundle is one in which the position of any given fiber on one end of the bundle corresponds to its position on the other end of the bundle. This is useful for transmitting images optically from one end of the bundle to the other:
I’m wondering how these bundles are made. Once you’ve got the fibers correctly positioned I expect it’s easy to lock down both ends of the bundle, but while you’re initially laying a bunch of highly flexible glass fibers together, how do you assure that the fibers never cross at oddball angles and result in the transposition of pixels in the transmitted image?
Copy machines, scanners, and the like don’t need a bundle with a round cross section because they are only imaging a one fiber thick line at a time. They start with the fibers laid out flat and retained at both ends or all along like a ribbon cable.
Sorry that I can only follow with a guess, but if a bundle or cable is needed I would do the same to start with. The flat cable can then be rolled up into a circle to terminate in the lens and the imaging receiver, or maybe just using software to correct the positioning at the receiver end. If the entire cable can’t be rolled and it must be twisted in the middle for strength and flexibility then only the ends would be retained in the flat form.
My understanding is that you start with fiberoptic loops bundled together and then you cut it. It doesn’t matter what the individual fibers do during the transit, just where they end up, and by cutting the loop, you’ll end up with the same fiber at the same place on both ends.
And of course any factory that makes spools of thread, rope, cable, whatever has the feed mechanisms to wind the product neatly in layers on the spool, which would avoid a chaotic in-between
Yeah, there’s lots of ways to do it. A lot depends on how big you want the input/output surface to be. I recall one method, where they stacked fiber optic pre-forms (basically over-sized fiber optic type devices, with all the necessary layers and such, just a lot bigger in cross-section) in a fixed array, and then used that fixed array to draw out the fibers, so they were effectively drawing out multiple fibers at once. You heat the thing up so it’s just soft enough to stretch, and then pull on one end fast enough to thin it out into a flexible fiber, like pulling copper wire from a copper block. The array of the pre-forms transferred to the final product.
I came in to answer this, but I see it’s already been answered.
The biggest problem is not breaking the fibers. I’ve seen lots of fiberoptic conduits with dark holes where individual fibers were broken.
One cute idea is to make your fiber bundle into a solid block , then heat it and pull it down so that one end is larger than the other. Then cut and polish the ends flat. This gives you a coherent fibertbundle that can expand or contract an image. Incom in Southbridge made a specialty of such Fiber Optics Tapers