Copper Tape Paper Circuit
This week, the assignment was about using copper tape to craft three circuits including coin LiPo battery (3V), LEDs, and resistors.
1. Simple Circuit
I named this design the “Sunrise”. It was inspired by the graphic on the piece of paper–a rising sun. The flipped corner is served both as a battery case and the switch. The layout of copper tape is shown in the first photo above, and there are two ports for the tape piercing through to the front side of the paper.
2. Two LEDs with Quote
For the second design, I think this line by the great philosopher Goethe, actually, his last words, fits the scene in a way of beauty. “Licht, mehr Licht”, “Light, more light”. I planted two red LEDs in the back of the paper, one behind each “Licht”.
With the experience from the “Sunrise”, I felt that the back side of the copper tape, with the layer of adhesive, has a lower level of conductivity. So I applied a reversed layer of the copper tape where lines contact. One caveat that I am not quite like was my layout, the far line is put between the two lines of the quote, so there appears a dark black line when it’s activated. Negative for the appearance, I should have thought about the effects from both side.
3. Multi-colour LEDs Layout
Thinking of origami, this old game came to my mind. I planted 2x green LEDs and 2x red LEDs for the design. In a premier testing, I found that 39-ohm resistor will do the work when red and green LEDs are set in a parallel layout. There are two parallel loops, each contains a switch and two LEDs in a parallel setting. The layout is not in a fine form. I used short papercut as a shield for bridging the copper tapes. The two resistors are used as bridges as well. It took me some time finding this functional design.
The circuit layout is shown in the first photo above. But when it’s folded, there will be unintended contact among the copper tapes. So I planted a folded facial tissue for blocking such contact. And it works great in actual playing. Here is a short video (as a gif) showing the design in play.