Take care of Eyes since these lasers are lethal for eyes. It can blind you before your eye lid will close. --- I am Not responsible for any damage.

Please Go through http://en.wikipedia.org/wiki/Laser_safety before reading and come to any determination about the topic.

We can burn things specially black or dark colored stuff by simple 3V battery but this will heat up the diode after intensive use. In case we need to make a Laser engraver which needs to operate over long time, Requires assembly to cool the diode down. How ever by using Joule Thief we can increase its brightness and eventually draw the heat away from diode to the transistor used. In fact I was able to run a 12V 10 Watt LED with a single MOSFET , It was very bright , using a third winding.the video is

How ever the Mosfet got very heated and unnoticed by me . Died.....!!!

Anyway I am still finding such MOSFET for Laser Applications.

For High Voltage generation visit

https://www.instructables.com/id/Simple-1-Inch-High...

Step 1: Setting Up Components

The basic requirement is any NPN transistor, a Laser Diode, a Ferrite ring,a resistance,A 3 V battery,Bread Board , Wires.etc.

The pin Configuration of BD139 is Front Facing E-C-B.

However any NPN transistor can be used.

Step 2: The Circuit of Joule Thief.

You may find this diagram every where throughout internet.The working principal is also as same as explained by others.

Step 3: The Laser Diode

This is specifically a Infra-Red Laser found inside a DVD Burner. I removed all optics and finally wanted to fix with the focusing lens. We can use any lens depending upon requirement and focusing length.

Step 4: The Toroid , the Heart......

This toroid was found from a CFL driver. 3 Turns each for each Winding. If the figure does not work out. Reverse the wire. i.e interchange the Blue and Violate wires.

Please try to understand the winding. If understood correctly, we can use any toroidal ring for the same purpose. Please Note that Torroidal Ring used in good SMPS have good performance against high frequency.

Step 5: All Connected and Its On

Connect every thing as per Circuit diagram.

IR laser from DVD/CD Burner connected to Joule Thief with BD139 and a 10K variable resistance. It can burn any black or dark color plastic,rubber etc. Take care of Eyes since these laser are lethal for eyes. It can blind you before your eye lid will close. --- I am Not responsible for any damage

You can take red laser or high power leds. Please also note to limit the supply voltage to 3 Volt Max else you will damage the diode. These diodes can bear 3.3V Max.