Editing Polymer (section)

===Optical properties===
Polymers such as [[poly(methyl methacrylate)|PMMA]] and HEMA:MMA are used as matrices in the gain medium of [[solid-state dye laser]]s, also known as solid-state dye-doped polymer lasers. These polymers have a high surface quality and are also highly transparent so that the laser properties are dominated by the [[laser dye]] used to dope the polymer matrix. These type of lasers, that also belong to the class of [[organic laser]]s, are known to yield very narrow [[laser linewidth|linewidths]] which is useful for spectroscopy and analytical applications.<ref name="D1999">{{cite journal|doi=10.1364/AO.38.006347|pmid=18324163|title=Multiple-prism grating solid-state dye laser oscillator: optimized architecture|year=1999|last1=Duarte|first1=F. J. |journal=Applied Optics|volume=38|issue=30|pages=6347–6349|bibcode= 1999ApOpt..38.6347D}}</ref> An important optical parameter in the polymer used in laser applications is the change in refractive index with temperature
also known as dn/dT. For the polymers mentioned here the (dn/dT) ~ −1.4 × 10<sup>−4</sup> in units of K<sup>−1</sup> in the 297 ≤ T ≤ 337 K range.<ref>{{cite book |title= Tunable Laser Optics |publisher= Elsevier Academic |location=New York |year=2003 |isbn=978-0122226960 |author= Duarte, F. J. |author-link= F. J. Duarte}}</ref>