Modifying (or moding) lasers is a way to sometimes increase their output power - if this has not been optimized by the manufacturer. Generally, moding a laser module requires opening up its housing and messing with its guts. Sometimes a bit of power improvement can be had, but often in the process of making the laser modifications, something will go wrong and the diode will be damaged or destroyed. Laser diodes are one of the most sensitive and delicate of electronic components, and merely touching one improperly can cause it to burn out (thanks to static electricity on one’s hands). Normally, opening the housing of a laser module will void any warranty it might have, so it’s wise to consult the module’s manufacturer before doing so.
Before attempting modifications on any laser module, make sure the power supply is removed or disconnected, and that any safety interlocks are properly in place. Pocket lasers do not contain high voltage power supplies or capacitors, but many lasers do, so make sure all capacitors are fully discharged before doing any mods. Until all power is disconnected and all capacitors discharged, be sure and wear proper laser eyewear.
There are several things for improving power, such as lens cleaning, which can be safely done to any laser without voiding the warranty. One of the most important things is anointing all accessible electrical contacts with oxide inhibiting grease (De-Ox), like that used by electricians when installing aluminum wire. In a laser which is powered by batteries, smearing a tiny bit on the battery contacts, and on the ends of each battery, can go a long way toward coaxing more power out of the laser. Pocket lasers generally have some manner of screw-in cap to hold the batteries in place, so be sure and lightly grease the threads on this cap. Only a microscopically thin film of oxide inhibitor is needed, so don’t smear large wads of it around to foul up other internal components. The use of De-Ox is not just for aluminum wiring or pocket lasers. It’s a great way to improve reliability in flashlights and other battery-powered devices. The stuff is fairly expensive, 1 ounce usually costing $5 U.S. dollars, but 1 ounce should be enough to treat at least 10,000 lasers or flashlights.