Improved diffraction gratings

Diffraction gratings were refined to contain around 15,000 lines per inch, enabling the creation of detailed solar spectrum maps. This advancement made it possible to analyze light with much greater precision.
 Henry Augustus Rowland United States 1882 Improved diffraction gratings

Diffraction gratings were refined to contain around 15,000 lines per inch, enabling the creation of detailed solar spectrum maps. This advancement made it possible to analyze light with much greater precision.