Red Versus Green Lasers

by Jennista Eastman (Spring 2019)

An Ocean Optics Photodiode Array was used to compare the wavelengths emitted from green and red lasers. A green and a red laser passed through a green and a red filter, respectively. The wavelength of red light ranges from approximately 635-700 nm and the wavelength of green light ranges from approximately 520-560 nm. However, this data shows another peak around 800 nm from the green laser. This is because of how a green laser works, which involves a three step process. A standard laser diode initially gives a wavelength of 808nm, which is focused on a neodymium crystal that converts the light into infrared with a wavelength of about 1000 nm. Finally, the light goes through a frequency doubling crystal that emits green light with a wavelength of 532 nm.