Hi Tom, Being an old Microwave engineer I don't believe that the information could be recaptured after bouncing around the tube, but an alternative optical method might work. A very wide angle lens at the top, looking roughly south configured to have a very long focal length on the back side, reflected down the tube and back out into a circular dispersing reflecting mirror to your more or less conventional sundial. There would probably be serious distortions in the signal, but the information would be there, possibly corrected with an aspheric lens within the system. Being an old Navy man as well, it seems that there were panoramic periscopes that might lend some clues. A raytracing or lens design program might be able to help.
Of course there are any number of ways that the information could be sampled and sent in a discrete fashion. A set of tubes or slits at the top with different colored filters at their inner end could reflect a color down the pipe to indicate the time for instance. I hope this starts a rush of thoughts that will help find an answer. Edley McKnight From: Tom Egan <[EMAIL PROTECTED]> To: sundial@rrz.uni-koeln.de Subject: Re: Sundial inside a room, but room is inside a canyon! > Hi John, > > Interestingly, the notion of a skylight is what got me going on this perhaps > quixotic quest. My > house is two stories high. The room where I want the indoor sundial is on > the first floor, so I'd > have to demolish most of the room above. My neighbor wouldn't mind this > particular demolition, > of course, but the grandkids who were used to sleeping there would, no doubt, > protest. > > This led me to consider an offshoot of the skylight concept. Some of my > neighbors have installed > a "solar tube" which provides a skylight effect in a remote room by > reflecting the sunlight down the > shiny inner wall of a tube roughly one foot in diameter. The light emerges > at the lower end of the > tube. It emerges quite brightly, I might add. > > I originally hoped I could install such a tube, mount a sundial beneath the > lower end and watch the > time go by from the comfort of my family room. I don't think it's that > simple, though. If the sun's > instant by instant azimuth and elevation in the sky is "information," then > that information must get > completely garbled up and lost as the rays bounce their way down the pipe. > > Fiber optics is certainly a way of preserving and transmitting the > information for use at a remote > location. But is there another way? > * Could the incoming light be polarized -- maybe in four sectors for N, E, > W, S information -- > to preserve the azimuth and elevation in its travels down the tube? > * Could some esoteric principles of radar be invoked to usefully tap into > the information at > various points along the tube, or at the end? (All I know about radar is > that the microwave > energy bounces around in hollow waveguides and the practitioners of the > black art are able > to somehow work magic with it.) > Tom > > John Carmichael wrote: > Hi Tom: > > Is a skylight hole in your roof possible? This would eliminate most of your > problems with mirrors. > You don't need a flat roof. A skylight hole could be used for any of the > interior dials I mentioned. > > > John L. Carmichael Jr. > 925 E. Foothills Dr. > Tucson Arizona, USA > Tel: 520-696-1709 > Email: [EMAIL PROTECTED] > Sundial Sculptures Website: http://www.sundialsculptures.com > Stained Glass Sundials Website: > http://advanceassociates.com/Sundials/Stained_Glass > - -