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DVD Burner: $12
Laser module: $5
Flashlight: $1
Miscellaneous components: $8
The power to burn: Priceless.

I was envious of the lasers they sell at Wicked Lasers that could burn and cut. However, they were a little out of my price range. Then I discovered DealExtreme. They sell cheap products with free shipping from Hong Kong. People seemed to like their $30 30mW green laser pointer, so I got one. It is very bright and the beam is clearly visible at night. Unfortunately, it is not powerful enough to burn or even make things warm. I doubt that it is really 30mW, and think it is averaging somewhere around 10. But, being a greenie, it is still about 10x brighter than a standard red pointer (1-5mW).

I've been spending a lot of time browsing around Instructables lately. Very recently did this new instructable pop up: Laser Flashlight Hack!!. It details how to remove a DVD Burner laser diode and insert it into a Minimag Flashlight. I had seen this before, but not paid much attention. It looked simple enough, and within my price range.

I got the DVD burner from eBay. It was "posessed" and open/closed on it's own. The laser diode still worked perfectly. It was a steal at $11.50, seing as the diodes alone go for $13. I also got the AixiZ module for the lens. Luckily, my order was placed fairly quickly after the Instructable came out, before hundreds of people ordered the same module and it went out of stock. It cost $4.50, but Aixiz seems to have forgotten to charge me shipping.

One problem with laser pointers is that they are usually run off of alkaline batteries. These batteries slowly fade out, and it's hard to tell, except for the laser gets less powerfull. Rechargable batteries are an alternative, which retain their full voltage potential until they go dead. But, they are only 1.2 volts, and laser diodes take 3 volts. Using rechargables will keep your laser running longer, but at a much lower power output. My solution was to regulate the power. The battery pack of 4-AA gives 6v or 4.8v. A regulator steps this down to 3.2v. This way, both types of batteries will work. Alkalines will last longer with the laser at full power, as they can drain down to about 4.5 volts before the regulator will drop below 3. Here is the regulator circuit:

• B1: 6 volts
• S1: Momentary push-button switch
• R1-R3: 470 ohms, 1/4 watt
• R4: 1k ohms, 1/4 watt
• C1: 100uF, 35 volts
• D1: Laser Diode

Smash the whole thing into a modified $1 flashlight (Minimags cost $10), and it's done!

This is a great low-cost project that is definitely worth the time and effort!

The rest of the instructions can be found on the Instructable, but be creative when it comes to housing. I don't recommend the 2-AA setup, and you will need a thicker (or longer) case for 4 batteries.

At these power levels, getting hit in the eye either directly, or even by a specular reflection, by these lasers, will blind you before you have time to blink. I recommend safety goggles (even I am getting some) when using these kind of lasers.

Green laser pointer from DealExtreme
	Red DVD burner laser in a shortened flashlight
Comparison of brightnesses. The center dot is a "normal" laser pointer as a reference.
	What's inside the flashlight case
Cutting electrical tape

The beam on both lasers is clearly visible at night, and both are about the same brightness to the human eye. Both can be seen on low hanging clouds.

Here is a video of the DVD burner laser cutting and burning.

Download High-Quality WMV (large)