https://en.wikipedia.org/wiki/Laser

https://en.wikipedia.org/wiki/Theodore_Maiman

https://en.wikipedia.org/wiki/Femtosecond

https://en.wikipedia.org/wiki/Photolithography#Light_sources

https://en.wikipedia.org/wiki/Lidar

https://en.wikipedia.org/wiki/Maser

http://www.hk-phy.org/articles/laser/laser_e.html

https://www.unilim.fr/a-fibre-laser-for-transmitting-secret-information/?lang=en

https://bigbangtheory.fandom.com/wiki/Helium-neon_laser

https://www.researchgate.net/figure/Characteristics-of-laser-and-light-emitting-diode-LED-endoscopy-LASER-light_fig1_329420725

https://www.hclco.com/Invisible_Laser_Radiation_Class_4_p/csl-xx51.htm

http://www.eli-np.ro/1st_user_workshop/