Having a pulling laser pointer is believed to be the dream of many children in childhood. which is why the laser pointer became popular in the past. However, the laser pointer of a toy does not exceed 5mW, which obviously cannot meet the desire for destruction hidden in most people. However, high-power (output power above 150mW) laser transmitters are very expensive and difficult to buy, so our dream for many years Is it doomed to ruin? No, as long as you follow the provided method and spend a small amount of time and money, you can make a high-power laser flashlight yourself. Although this thing can't kill people in an instant, it is still not used to light candles and bully small animals. questionable.
First you need an old DVD burning drive ("Gao Fu Shuai" can buy a brand new one, Xiaobian will not stop you). It can be a desktop computer drive or a laptop drive, as long as the laser head is not aging and scrapped. The best is 16X, because the output power of the green laser pointer of the 16X recording head is large (up to 250mW), of course, the 8X is also okay, but the power is much smaller, generally only 140mW, the lethality is greatly reduced.
Buy a suitable flashlight, a small pen-shaped flashlight is also available, but the size should not be too compact, and the most important thing is that the light bulb (preferably a single light bulb) can be completely removed, so as to facilitate the transformation. Flashlights are sold in all major supermarkets, with prices ranging from 20 yuan to several hundred yuan. Buy the cheapest one according to requirements. Of course, don't forget to buy a few batteries of corresponding specifications.
In addition to visible light, some green laser pointers emit infrared infrared (IR) light. For example, a laser tested by a US government agency has a slight visible green light while outputting 20mW IR (four times the US legal limit). In this technique, the large spectral width of ultrashort pulses from an oscillator is used to extend them in a reversible manner. Thanks to the diffraction grating, each spectral component (each "color") of the pulse is separated and passed through a path of different length before being recombined into the same beam using a second grating. In this way, a pulse that is stretched a thousand times longer is obtained, which can pass through the amplifier without damaging them, thereby obtaining the required energy, each pulse up to a few joules or more.