I bought this green laser pointer module online. This is a 5mW green laser with a wavelength of 532nm. In fact, its output can be several times the nominal power-it is conceivable that it is not safe to do so, and more importantly, it breaks the warranty! !! !! The measurement shows that it has 15mW output when no adjustment is made, and 20mW when it is adjusted to the maximum value. This means that this laser is not suitable for people without basic laser knowledge and protective equipment. Light can also be seen from the comparison of its appearance with ordinary laser pointers, which is a very dangerous thing.
But it doesn't stop there. When the laser module works continuously for a period of time, the power is often greatly reduced due to temperature rise. Most green laser pointer modules require temperature control to maintain stable output. This module is only designed for cheap laser pointers and has no temperature control function, so I equipped it with a temperature control device and external laser modulation.
Since the accuracy of temperature control is so common, I used simple proportional integral control. The processor reads the resistance value of the thermistor on the laser module, converts it into a temperature value, and then drives the semiconductor refrigeration chip to adjust the temperature according to the difference from the set temperature. The laser output can be modulated by the main control chip. and it will automatically shut down to protect the laser when the temperature is too high.
This is an area that is easily confused. 200mW Laser Pointer When you use a unit that consumes less power to play balloons, you need to remember the color of the target. For example, trying to blast a white balloon will actually reflect a lot of light and heat from the balloon rubber, which makes blasting at low power more difficult, if not impossible. Of course, an easy way to solve this problem is to use a high-level IV laser over 500mW or just use a black balloon. By using a white balloon to draw a circular target with black magic markers, you can actually change the way the balloon rubber absorbs heat and light. The same goes for match heads. Place a black magic mark on it to reduce the burning time.