Tau.Neutrino said:
Tau.Neutrino said:
Imaging system allows entire eye to be examined with one instrument
Eye exams may be getting quicker and easier, plus ophthalmologists may be able to save money on equipment, thanks to a new instrument developed by scientists in Poland and Spain. Unlike existing eye-examining technology, it allows the entire eye (from front to back) to be imaged via a single lens.
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Could this system be used in microscopes and telescopes?
Maybe it could be used in cameras as well?
When in CSIRO I was looking into the possibility of using something similar, but for a different purpose. What I had in mind was a manually-tunable infinitely-tunable filter. The filter contains cavities filled with a fluid and dye, and by turning the outside ring(s) the fluid was squirted into and out of the cavity between the plates. Dial it up one way and get a neutral-density-filter, or a blue filter, red, or yellow filter or any combination in between and of any depth of colour.
It could be electrically mechanised, but that’s a different problem.
Only a couple of years after I came up with this, someone else came up with the OCT. “At the heart of it is a container filled with a clear optical fluid, sealed with a transparent polymer membrane on the front – that membrane is the lens, and it can incrementally change shape. When an electrical current is applied, the membrane gets pushed down into the container by a ring-shaped structure, causing it to bulge against the fluid. When the current ceases and the membrane moves back up, the convex bulge becomes a concave bowl.” So it’s similar to my design in that a fluid is pushed into and out of a compartment by adjusting a ring, but different in that in OCT the compartment membrane is flexible (mine is rigid) and there’s only one (mine could just have one for a neutral density filter, but would need at least three if you wanted full colour control).
What worries me about OCT for camera and telescope use (not necessarily for microscope) are two things. One is that the lens shape won’t be perfect, you won’t get an optically perfect lens by just causing a membrane to bulge. The second is that there’s going to be a lot of chromatic aberration, different wavelengths will focus at different distances.