On Murdoch's Mysteries, the technophile detective at the end of the Victorian era made, in one episode, night vision goggles that used mirrors surrounding the eyes, essentially a pair of reflecting telescopes with no magnification.
It would not cover the same angle, though: just straight ahead. The naive design you might throw together would handle light arriving parallel to straight forward, so the actual field of view may or may not be useful. To purposfully make a field of view of a specific size and quality would require knowing something about it.
A common SLR photography lens has an enormous opening compared to your pupil, and high quality formerly pro lenses for pure mechanical film cameras can be found cheaply. Some designs even have a lens board for mounting, rather than a fixed camera enclosure.
In their original use, they project the image on a large (relative to your eye) screen, so produce an image dimmer than life. However, if instead of making a projection 44mm in diameter (say), you added an objective lens made for telescopes or a handy jewler's loupe (any magnifying glass works, but for more than 5× you need a fancy compound lens), you could project all the light into your eye.
Update: using on-hand materials it takes 3 pieces, not 2, and is unacceptably long (unless you want it looking like an old seafarers telescope). To concentrate the entire collected light, the next lens needs to be very large around to scoop in all of it. a hand-magnifier doesn't result in an image as large as the directly-observed target, and a powerful loupe is not large enough.
No comments:
Post a Comment