Ultraviolet LED flashlights are widely used for a variety of purposes. The LED lights are powerful and energy efficient, while the ultraviolet layer makes the flashlight useful for detecting counterfeit bills. With an ultraviolet LED flashlight, you can also detect sun burns, use the light for sterilization, and as a pesticide. UV LEDs, however, can be very expensive. Here’s how you can make your own.
- Prepare the flashlight. Purchase a regular flashlight that runs on the usual four pieces of 1.5 volt batteries. You will use this as the frame for the UV LED flashlight. Take the bulb out of the flashlight, and use scissors or clamps to heat the collar of the bulb using a soldering iron. Once the solder has sufficiently cooled down, use the scissors to tap away the solder pieces remaining in the bulb. You should see a small hole at the collar of the light bulb, where you will fit in the UV LED bulbs.
- Add the resistor. Take a resistor, which should be 100 ohms, and use the soldering iron to attach the resistor onto the positive plate on the flashlight. Since both the positive and the negative leads are usually of the same height in a usual flashlight, you can use needle nose pliers to bend the filament of the negative lead away, at an angle of 90 degrees. The negative lead should point away from the bottom of the LED bulbs attached to the soldered light bulb collar. Trim the resistor by using scissor clamps, until the leads on the resistor are only half an inch in length.
- Insert LED bulb. Next, take the LED bulb and attach it onto the flashlight buy inserting the leads of the bulb through the hole in the soldered light bulb collar. The bulb should be positioned as close as possible to the original position. Allow the free lead from the resistor to maintain the 90 degree bend, which should drop on the base, into a slot on the solder.
- Connect the negative lead. Next, connect the negative lead to the base’s side. The rosin flux can be used to do this. Trim away the excess leads after soldering, and attach the lead to the bulb base. There should be no excess lead that sticks away from the outer parts of the bulb base. If there are excess leads, bend these into the shape of the bulb base. The bulb base should have enough lead surfaces to become the contact point between the LED flashlight batteries and the actual bulb.
- Attach the bulb into the flashlight. You will now have an ultraviolet LED flashlight. You can now attach this to the flashlight. Insert the batteries and check whether the leads are properly positioned. If properly positioned, the UV LED bulb should light up.
In a few minutes and materials that are available in most electronic shops, you can create your own UV LED flashlight. Use the UV LED flashlight at home or in the office, for detecting hidden stains or for authenticating bills and documents.