Engineering News Blog

Engineering News

Latest news of interest to engineers. Sourced from GlobalSpec's Engineering News

Previous in Blog: AMP-Foot 2.0 Prosthesis Gives the Power of Real Feet, Keeps a Light Step   Next in Blog: Ethiopian Kids Hack OLPCs in 5 Months With Zero Instruction
Close
Close
Close
3 comments

Indoor Sundial

Posted November 01, 2012 9:57 AM

From Neatorama:

How does Tom Egan's sundial work? It reflects light inside without distorting its original direction:

a novel indoor sundial using an externally mounted convex mirror to compress the entire visual arc of the sky down to the size of the mirror. A pinhole in a mask on the window acts as a camera obscura, projecting the image of the sun onto an indoor dial face that can be as small as a letter-size piece of paper. The system has four parts: A convex mirror mounted just above the roof line; a pinhole lens affixed to the window; and two paired flat mirrors to relay the sun beam from the convex mirror through the pinhole and onto the dial face inside the building.

Read the whole article

Reply

Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".
2
Guru

Join Date: Mar 2012
Posts: 2191
Good Answers: 84
#1

Re: Indoor Sundial

11/01/2012 12:53 PM

Seems like an awful lot of trouble when you can just put one on Mars and watch it with a camera. You know, remotely?

Reply Good Answer (Score 2)
Guru

Join Date: Apr 2010
Location: About 4000 miles from the center of the earth (+/-100 mi)
Posts: 9046
Good Answers: 1031
#2

Re: Indoor Sundial

11/02/2012 6:53 AM

If you have a window on the south side of the house, just hang something in the window and mark where the shadow falls - Indoor sundial.

Reply
Guru

Join Date: Mar 2012
Posts: 2191
Good Answers: 84
#3
In reply to #2

Re: Indoor Sundial

11/02/2012 2:47 PM

You realise of course that this configuration works for less than half the planet and, for one broad strip, not at all? :)

Reply
Reply to Blog Entry 3 comments
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".

Previous in Blog: AMP-Foot 2.0 Prosthesis Gives the Power of Real Feet, Keeps a Light Step   Next in Blog: Ethiopian Kids Hack OLPCs in 5 Months With Zero Instruction

Advertisement