A tale of two lamps

Tue, 04/30/2013 - 4:19pm
Karl Stephan, Consulting Engineer, Texas State University, San Marcos

A few months ago, my wife bought a lamp at an office-supply place to light up the table where my father-in-law plays dominoes with us. He’s 87 and his eyesight isn’t what it used to be, so having lots of light in the right place is important. The ceiling light doesn’t quite do the job.

I was impressed with her purchase. It’s an elegant-looking design that unfolds. When it’s folded it’s just an oblong white plastic pillar on a round stand, about ten inches tall. It unfolds like a book hinged at the top, and when you unfold it you find that the upper inside surface is lined with thirty white LEDs that turn on as the hinge opens up. You can set it at a convenient angle and it casts a smooth, even white light over several square feet.

It cost only twenty bucks or so, but it had a significant disadvantage in my view: it ran only on batteries, unless you bought a separate power supply (not provided). After finding that the batteries would last maybe four or five hours at the most, I did a quick calculation and concluded to buy a plug-in “wall wart” for the thing. I had to go to Radio Shack and assemble a custom one from their array of general-purpose power supplies, and spent about $25 on that. But once I got the lamp hooked up to the mains, it worked fine, and we have probably used it daily for the last six months or so....

Check out the rest here:


Share this Story

You may login with either your assigned username or your e-mail address.
The password field is case sensitive.