The Light Ghost

The original idea is from Tobias Wong, who put a solar light into a jar and called it sun jar. I thought this might fascinate kids and I was right. It's fun to build with your children and it's even more fun for them to show it around and tell the story of a mysterious light ghost.

What you need:

• A cheap solar garden light with plastic housing
• A glass jar big enough for the solar cell to fit in
• cling foil
  
• Tools: diagonal cutter and hot glue
• Optional: a colored LED and a soldering iron

The whole idea is to put a solar LED light into a glass jar and invent a nice story for it: the light ghost! The ghost is captured in the jar and collects light when the sun is shining. As soon as it gets dark, the ghost will start glowing letting go the collected light.

Assembly: We need a working solar LED light as a basis. I chose a cheap solar garden light with plastic housing, as it is easy to disassemble and unneeded parts are simply cut away. All you need are the solar cell, the battery and the electronics including the LED. I hot glued the solar cell into the jar lid and then glued the battery holder and the electronics to the backside of the solar cell (the solar cell is facing upwards of course). The LED is facing downwards to illuminate to jar. My solar light also had a LDR (Light Dependent Resistor; to sense if it is dark or not). I made it look sideways, because it mustn't be exposed to the light coming from the LED, which would result in a blinking LED.

I covered the battery and the electronics (apart from the LED and the LDR) which black tape so that it cannot be seen. Then I filled the jar with cling foil, which  creates a nice mysterious light.

Optional: Solder out the LED and replace it by a colored one. Adds to the ghost story ;-)