#Tech-Ingredients #video about #jugaad #laser directed-energy #weaponry against #drones #toread
on 02025-10-18#video #toread about #laser engraving on metals in color
on 02025-08-31#video on #laser diode wavelength stabilization by adjusting the drive current and temperature (using a resistive heating element!) to compensate for wavelength shifts. Demonstrates “mode hops” on an oscilloscope; the initial heating using a temperature sensor (a transistor I think) is to get it to a mode-hop-free region, and then the current is PID-controlled to stabilize the wavelength, and a second control loop adjusts the temperature to “desaturate” the current controller. He says he got the wavelength stabilized to ±2nm “over a range of 200mm”, which I think means 10⁻⁸, not 2/555 or so. #optics #toread #hardware
on 02025-04-12#video on a Luxmux’s “Ultrawide Tunable Fabry Perot #Laser G5” #optics
on 02025-04-04DIY metal #3D-printing (SLM of 316 stainless) #bootstrapping with a 155-watt #laser coupled in through a fiber running at up to 300mm/s, getting better results at higher speeds and higher powers. Wow, I had no idea that surface tension gradient with temperature was a thing, but apparently you can reverse it by adding sulfur to stainless, resulting in a reversal of Marangoni convection! Eventually his 3-D printed ASA lens housing overheated and hazed his lens and fiber. #materials #video
on 02024-04-03Fazal’s photo of his #laser #engraver work
on 02024-02-0225-watt fiber #laser #engraver for US$2500 capable of cutting steel (10 microns at a time)
on 02024-02-02killing #mosquitoes with a #laser: a few millijoules from megawatt green or far-infrared lasers suffices.
on 02016-02-19cheap DPSS green #laser sources can have interferometry over meters.
on 02015-11-10#interferometry using cheap #laser diodes; apparently feasible with some of them to do interferometry over meters.
on 02015-11-10Thread on Practical Machinist forums about Dan #Gelbart’s videos, and in particular a #machining centering device he made with a small #laser.
on 02015-08-16A tech note from cylindrical-lens manufacturer Newport: circularizing the beam from a #laser diode with two cylindrical #lenses with different focal lengths and perpendicular axes, since laser diodes have elliptical divergence. Why has nobody done this for regular magnification? Cylindrical lenses are dramatically easier to manufacture than spherical lenses! There must be a reason it won’t work.
on 02015-08-12