Fingertip-Sized Rechargeable Flashlight Might be World’s Smallest

Gadget Industry, a DIY enthusiast, wanted to explore the possibilities of miniature tools. So, they created a custom rechargeable flashlight that sits comfortably on the tip of your finger, and it just might be the world’s smallest.

The first step in creating one of these is to begin with a tiny 60mAh lithium-polymer battery as the main component. From here, the builder begins disassembling a conventional TP4056 charging board and reconstructing the components onto the battery to minimize space wherever possible. A touch sensor module is then given the same treatment, jammed in firmly. Finally, an N-channel MOSFET is connected to the sensor and a small white LED, essentially converting the touch of a finger into an on-off switch.

Charging occurs via a small USB-C port on the device itself; simply plug it into a suitable charger or computer, and the battery will charge without the need for any additional wires. The entire assembly is covered in a layer of epoxy resin to provide protection. To seal the port, a small amount of clay is inserted before the resin solidifies and carefully removed later.

The single white LED provides just enough light to make a difference in close quarters, such as finding a lock in the dark or checking under furniture on the go. Touch activation works flawlessly, cycling the light on and off with dependable precision. The brightness level will vary depending on the LED you choose. The battery life ranges from minutes to hours, depending on how much you use it, and it can be rapidly recharged to be back up and running.

Another advantage is that the resin casing is quite resistant to scratches, bumps, and other small impacts, with the exposed circuitry secure from harm caused by daily use. Of course, water resistance is a different story, as you should most certainly avoid immersing it or subjecting it to heavy downpours.

When compared to a commercial keychain light from a manufacturer like Nitecore or Olight, this one clearly makes some sacrifices. For one thing, it only has one brightness mode and produces far less light, yet it is only a tenth of the size. Those off-the-shelf solutions are a couple of inches long and capable of producing hundreds of lumens, whereas this one is an exercise in complete minimalism; it’s something you can carry without even realizing it’s there until you need it.
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