AUTHOR=Micó Vicente , Pedrini Giancarlo , Lei Ming , Zuo Chao , Gao Peng TITLE=Editorial: Optical Microscopic and Spectroscopic Techniques Targeting Biological Applications JOURNAL=Frontiers in Physics VOLUME=9 YEAR=2021 URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2021.752435 DOI=10.3389/fphy.2021.752435 ISSN=2296-424X