This red (650nm wavelength) laser diode module is easily powered by a 5V DC USB power supply or battery and can be used as a pointer, for illumination, and light therapy. Wires for the DC power are soldered to the 6mm brass laser diode housing. The module includes an internal 91-Ohm current limiting resistor, so no additional series resistor or current limiter is required. Simply connect 5V DC power to use! The Red lead is Positive (+), and the Blue or Black lead is negative (-).
The lens is acrylic plastic and can vary somewhat in its ability to focus to a small spot. If necessary, the spot size can be focused by rotating the threaded brass lens holder in either direction.
Warning: Never look straight at any laser diode while it is operating, or point it at someone’s eyes, as eye damage is possible even with eye-safe lasers like this one.
10x (10 pieces) 650nm 6mm 5V 5mW Red Dot Laser Diode Modules with Wire Leads