Half will go to Arthur Ashkin, of Bell Laboratories in Holmdel, New Jersey, for "optical tweezers and their application to biological systems."
The other half will jointly go to Gerard Mourou, from Ecole Polytechnique in Palaiseau, France, and the University of Michigan in Ann Arbor, and to Donna Strickland, of the University of Waterloo, in Ontario, "for their method of generating high-intensity, ultra-short optical pulses."
The inventions revolutionized the field, the Royal Swedish Academy of Sciences noted in its announcement.
"Extremely small objects and incredibly fast processes now appear in a new light," the academy wrote. "Advanced precision instruments are opening up unexplored areas of research and a multitude of industrial and medical applications."
The optical tweezers created by Ashkin can manipulate living cells like viruses and bacteria without damaging them.
Mourou and Strickland's work resulted in "the shortest and most intense laser pulses created by humankind" -- allowing for incredibly precise cutting or drilling through living matter. Their technique is called chirped pulse amplification (CPA).
Strickland is the third woman to get the Nobel Prize in Physics, following Marie Curie in 1903 and Maria Goeppert-Mayer in 1963.
"We need to celebrate women physicists because they're out there ... I'm honored to be one of those women," Strickland said.
The 2018 Nobel Prize in Medicine was awarded to James P. Allison and Tasuku Honjo on Monday, for their breakthrough in cancer research.
The Nobel Prize in Chemistry will be awarded on Wednesday, and the winner of the Nobel Peace Prize will be announced on Friday. This year's Nobel Prize in Literature has been postponed.
: The bright physics of light and color.
: Last paper published in physics journal.