This is fun, making a single multi-core fibre have lots of bright points along it, that we can turn on one at a time.
Hari spent lots of effort trying to get these emitting fairly evenly.
I think this might be really useful for medical sensing through the length of a human organ (see text below), as well as for our medical device placement work!
“It is possible to imagine many potential photonic applications, we consider in more detail how this fibre technology can benefit a few spanning biomedical sensing, imaging, and therapy. In photobiomodulation  or photodynamic therapy (PDT)  applications, delivering light to specific areas of tissues or organs for photophysical and photochemical effect is an essential criterion. However, guidance of in-vivo instrument insertion can be challenging. This technology would offer the possibility of fibre placement internally and post-selection of the illumination region. While results presented here demonstrate 1 cm separation between illumination points, closer separation would be easily achieved for finer control. As such specific organ regions could be illuminated, with >55% throughput offering efficient delivery of therapeutic light.
Discrete light emission (and therefore collection) provided by these fibres is also potentially enabling in medical diagnostics in the form of spectroscopic investigation at multiple points along a medical device throughout an organ or extended tissue structure. In the case of therapeutic treatment (photobiomodulation  or photodynamic therapy ) this offers determination of which emission locations should be subsequently used for treatment, for instance observing where the PDT agent has accumulated in tumours through its fluorescent properties (). Thus, the selectivity of the light emission/collection location demonstrated here removes the need for precise instrument placement.”