The color of lasers with 561nm wavelength is neither yellow nor green. The 561nm laser is yellow green.
561nm Yellow Green Solid State Laser DPSS Source .
There are following types of 561nm laser:
Single Longitudinal Mode Laser
Low Noise Yellow Green Laser
High Stability Yellow Green Laser
Yellow Green OEM Laser Module
Fiber Coupled Laser System
The laser applictions for the 561nm lasers:
imaging microscopy
More informations about 561nm solid state laser:
DPSS yellow-green 561-nm lasers for improved fluorochrome detection by flow cytometry .