Maglite Laser

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A normal DVD burner laser diode is rated 200-300 mW and compared to the regular 5 mW laser pointer, it is a lot more powerful and potentially dangerous.

IMPORTANT: Please read the laser safety instructions and regulations before working with lasers, Wikipedia or Felesmagus

Extract Laser Diode

The DVD burner I used was an old Sony DW-U10A 4x model with a Class 1 laser.

Maglite laser dvd burner.jpg Maglite laser dvd burner label.jpg

Remove the cover and get to the two tracking rails holding the laser unit.

Maglite laser dvd burner remove cover.jpg Maglite laser dvd burner laser unit rails.jpg

The laser unit has two lasers, one for DVD and one for CD (correct?). It's hard to tell the two apart and the easiest way is to try one and then the other.

Be aware that some lasers do not beam visible light and can still damage your eyes [1]. Always beam away from you with no reflective areas around.

Maglite laser unit top.jpg Maglite laser unit bottom.jpg

The hardest part of the project is to get the laser diodes out of the heat sink. The diode is normally glued and hard to press out. I had to bend the aluminum with a plier and crack the heat sink at the weakest points.

Solder two wires to GND and LD+, the third is not used and is for a optional photo diode. Use a single AA battery to try the diode, always do this away from you and not looking at the diode.

Maglite laser diagram.gif

Maglite laser diode front.jpg Maglite laser diode back.jpg

Now remove the PCB and clear up the diode.

Maglite laser diode pcb.jpg Maglite laser diode clean.jpg

Maglite laser diode clean front.jpg Maglite laser diode clean back.jpg

Diode Mount

To mount the diode in the maglite, find a suitable housing case to fit the 5.6 mm laser diode. I used a 5 mW from AxiZ.

Maglite laser axiz housing.jpg

Remove the old laser using a plier or screw driver.

Maglite laser axiz remove diode.jpg

The front of the Axiz housing is the focus ring and is used to tune the laser later.

Maglite laser axis diode focus.jpg

The pins on the diode is too short and needed to be extended.

Maglite laser diode pins extended.jpg

The diode will become warm after even a few minutes of use. Artic Silver 5 therman grease will help the thermal transfer.

Maglite laser artic silver.jpg Maglite laser diode mounted.jpg

Maglite laser diode mounted side.jpg

Maglite Preparation

The Maglite is a AA model with a screw ring to turn it on and off. Without the front screw ring/reflector/glass the light is always on. Double AA batteries will provide 3 volts (2x 1.5v).

Maglite laser maglite.jpg Maglite laser maglite light.jpg

Under neath the black ring is the positive and negative poles, the one to the right is negative. The hole in the middle of the black ring has to be widened to fit the diode pins.

Maglite laser maglite poles.jpg Maglite laser maglite black ring.jpg

The reflector also needs to be widened to fit the Axis housing. I used a massive drill and drill-bit, but a Dremel would be better.

Maglite laser maglite top.jpg Maglite laser maglite reflector.jpg

Maglite laser maglite reflector front.jpg

Assembly

The diode is mounted with extended pins and the Maglite is modified to fit the housing. Remove the batteries from the Maglite now!

Put the pins into the socket of the Maglite body and put the batteries back. Be careful from this point on! Use the focus ring to find the fine point of the beam. Avoid looking extended times at the reflected dot.

Maglite laser housing mounted.jpg Maglite laser housing mounted side.jpg

To avoid the pins to be twisted, I applied a single round of Kapton tape. It is highly adhesive and good for electronic use.

Maglite laser housing kaptop.jpg Maglite laser housing kapton top.jpg

Put top back on. The top screw ring is composed of the top ring, glass, and modified reflector.

Maglite laser screw ring.jpg

Once everything is put together and the screw ring is fastened, the laser housing focus ring should fit just underneath the glass.

Maglite laser done front close.jpg Maglite laser done perspective.jpg

Only use this to learn how lasers work, remove the batteries when not in use and mark the Maglite of the laser danger.

References