Editing Tunable laser (section)

===History===
The first true broadly tunable laser was the [[dye laser]] in 1966.<ref name=schafer90>[[F. P. Schäfer]] (ed.), ''Dye Lasers'' (Springer, 1990)</ref><ref>F. J. Duarte and L. W. Hillman (eds.), ''Dye Laser Principles'' (Academic, 1990)</ref> [[Theodor W. Hänsch|Hänsch]] introduced the first narrow-linewidth tunable laser in 1972.<ref name=hansch72>{{cite journal |last1= Hänsch |first1= T. W. |year= 1972 |title= Repetitively Pulsed Tunable Dye Laser for High Resolution Spectroscopy |journal= Appl. Opt. |volume= 11 |issue= 4|pages= 895–898 |doi=10.1364/ao.11.000895 |pmid= 20119064 |bibcode= 1972ApOpt..11..895H}}</ref> Dye lasers and some [[vibronic spectroscopy|vibronic]] solid-state lasers have extremely large bandwidths, allowing tuning over a range of tens to hundreds of nanometres.<ref>Koechner, §2.5, pp66–78.</ref> [[Ti-sapphire laser|Titanium-doped sapphire]] is the most common tunable solid-state laser, capable of laser operation from 670&nbsp;nm to {{formatnum:1100}}&nbsp;nm wavelengths.<ref name="steele91">{{cite journal |doi=10.1364/OL.16.000399|title=Broadly tunable high-power operation of an all-solid-state titanium-doped sapphire laser system |year=1991 |last1=Steele |first1=T. R. |last2=Gerstenberger |first2=D. C. |last3=Drobshoff |first3=A. |last4=Wallace |first4=R. W. |journal=Optics Letters |volume=16 |issue=6 |pages=399–401 |pmid=19773946 |bibcode=1991OptL...16..399S }}</ref> Typically these laser systems incorporate a [[Lyot filter]] into the laser cavity, which is rotated to tune the laser. Other tuning techniques involve diffraction gratings, prisms, etalons, and combinations of these.<ref name=duarte90>F. J. Duarte and L. W. Hillman (eds.), ''Dye Laser Principles'' (Academic, 1990) Chapter 4</ref> [[Multiple-prism dispersion theory|Multiple-prism grating arrangements]], in several configurations, as described by [[F. J. Duarte|Duarte]], are used in diode, dye, gas, and other tunable lasers.<ref name=duarte15>[http://www.tunablelaseroptics.com F. J. Duarte, ''Tunable Laser Optics'', 2nd Ed. (CRC, New York, 2015) Chapter 7.]</ref>