Sundials have gnomons, usually a triangular thing in the middle. At first thought making a gnomon out of lens glass, perhaps with something like a marble at the top would make a bright spot appear on the edge markings.

It might be a little more complicated than that though, as the day progresses the focal distance of the double-convex lens, or marble, changes.

I think with optical modelling software, A Gradient Refractive Index (GRIN) lens, or a few marbles, something could be done.
-- beanangel, May 25 2018

Sundials https://en.wikipedi...al#Unusual_sundials
Some similar to what you describe, using light instead of shadow. [neutrinos_shadow, May 28 2018]

https://www.etsy.co...&utm_content=140550 [2 fries shy of a happy meal, May 30 2018]

Luneburg lens https://en.wikipedi.../wiki/Luneburg_lens
What I think is being proposed to use [notexactly, Jun 02 2018]

Does this mean there could be a single column of glass with various internal densities that if orientated correctly, will act as a sundial?
-- wjt, May 25 2018


No, mon.
-- RayfordSteele, May 26 2018


Since the focal length is fixed, you want to use an equantorial sundial. There are other weird types; see the Wikipedia page (linky).
-- neutrinos_shadow, May 28 2018


Looking superficially at [neutrinos_shados]'s link. I got had the thought of X-ray crystallography. Could a 3D atomic arrangement of a clear marked curved vase be so arranged to act as a light concentrator displaying the hour. Because location is paramount, the vase would be individually made to locations.

The future extrapolation of the sun vase would have induction power and alter atomic structure, via powerful magic smoke, to suit season and location. Of course it would be a desktop toy as GPS would be at the micro-m scale with corresponding time.
-- wjt, May 29 2018


Ever wander into a conversation not being entirely sure you speak the same language?
-- RayfordSteele, May 29 2018


[RayfordSteele]; even when I'm talking to myself...
-- neutrinos_shadow, May 29 2018


It all comes down to what is in the 'space', a solid, loops, strings or the dimensional magic trick of nothing.
-- wjt, May 30 2018


Here's the most unusual one I've seen. [link]
-- 2 fries shy of a happy meal, May 30 2018


Thanks [2 fries shy of a happy meal], An internal gnomon using atomic spaces might be possible.

I did imagine a column that, because of the high energy particles and wave energies from Sol, would display a ring of phosphorescence. The cylinder surface light ring emitted would be 90 degrees to Sol's current position. I was imagining cross talk between the energy rain particles and waves that would react inside the cylinder and bleed horizontally, initiating phosphorescence.

Then again, a column of LEDs, with a clock chip, could compute and light the exact same thing. This method, sadly, is just not a physical cascade reality.
-- wjt, May 31 2018



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