Step 1: De-solder the diode
Remove the batteries and twist the cap to disassemble the laser pen. Then you need to rotate out or pull off the cap. The laser diode and driver circuit board would be exposed.
Step 2: Disassemble the DVD-RW drive
Remove the screws on the metal housing to disassemble the DVD-RW. By removing the screws on the left rail, the entire apparatus will easily slide out. The ribbon cables can be cut, as they will not be used.
Step 3: Get the laser diode from the DVD-RW laser housing
Remove the laser diode from the DVD-RW laser housing. It will resemble the cylindrical laser diode from the disassembled pen. Carefully use the tweezers or pliers to slide the diode out without damage.
Step 4: The top pin is for the positive lead, the bottom negative.
Solder the DVD-RW diode to the contacts on the laser pen’s circuit board, making note of the correct orientation of the three diode contacts. The pin to the right can be grounded to the case of the laser pen (if it is metal), but it is not required.
Step 5: Reassemble the laser pen.
The DVD laser diode is now being driven by the batteries and will have the power to burn soft materials. Should the circuit board fail, or a more powerful laser pen is desired, replace the driver board with a stronger one