Solar torch business card
by seer on Oct.25, 2010, under My gadgets

This is a business card. But in additional to its original function, it has more usage. There is a touch imbedded in the center of the image. When you touch the double E sign, the led will shine. The battery stores the energy from the solar panel. So it never requires the battery replacement.

The circuit is quite similar to a solar touch. A 4.5V amorphous silicon based solar panel charges the 3.7V Li-Ion battery through a 0.7V drop diode. But I use a touch switch instead of a regular switch. The finger is a weak conductor so I use two transistors to form a Darlington. The high gain of the circuit will supply enough current to light the led with a few micro-ampere through the finger tip.
May 2nd, 2012 on 9:43 pm
Hi,
What is the thickness of these cards?
Great Idea!
May 3rd, 2012 on 12:31 am
2mm
January 6th, 2015 on 11:41 am
I was wondering if there was a way to produce theses cards in quantity? I know it would probably be rather expensive, however i think it would be amazing advertisement for my company. ( AllSolarIdaho.com )
Thanks!!
December 7th, 2016 on 2:38 pm
I am very interested in this card. How can i get them11/
April 9th, 2017 on 3:13 pm
Please give me a price I would love to use this product to market my current portfolio of solar companies.
May 17th, 2017 on 11:28 am
Hello,
I have recently joined a solar energy selling company. We are looking for business cards. How much are these? Thanks so much, Angela
August 1st, 2018 on 9:10 am
Nice! Are you producing them? We’d like to buy some.
September 10th, 2018 on 5:27 pm
This is a perfect business card for our business. Are you producing them and if so, how much is the cost and what is the minimum order?
Thanks
July 22nd, 2019 on 12:11 pm
Would like to inquire about ordering some of these.