{{short description|Use of optical interference patterns to visualize small objects}}
'''Interference microscopy''' involves measurements of differences in the path between two beams of light that have been split.<ref name="irm_pmc">{{cite journal | last1 = Barr | first1 = Valarie A. | last2 = Bunnell | first2 = Stephen C. | title = Interference Reflection Microscopy | journal = Current Protocols in Cell Biology | date = 2009 | volume = 45 | pages = Unit 4.23 | doi = 10.1002/0471143030.cb0423s45 | pmid = 20013754 | pmc = 2824538 }}</ref><ref name="grom_quantitative_phase">{{cite journal |author1=Jinming Zhang | author2= Mirsaeid Sarollahi | author3 = Shirley Luckhart | author4 = Maria J. Harrison | author5 = Andreas E. Vasdekis |title=Quantitative phase imaging by gradient retardance optical microscopy |journal=Scientific Reports |date=April 29, 2024 | volume= 14 | issue= 1 | article-number= 9754 | doi= 10.1038/s41598-024-60057-y | pmid= 38679622 | pmc= 11056386 | bibcode= 2024NatSR..14.9754Z }}</ref><ref name="interference_microscope_objectives">{{cite journal |author1=Peter J. de Groot | author2 = James F. Biegen | title=Interference microscope objectives for wide-field areal surface topography measurements |journal=Optical Engineering |volume=55 |issue=7 |article-number=074110 |date=July 21, 2016 | doi = 10.1117/1.OE.55.7.074110 | bibcode = 2016OptEn..55g4110D |url=https://www.spiedigitallibrary.org/journals/optical-engineering/volume-55/issue-07/074110/Interference-microscope-objectives-for-wide-field-areal-surface-topography-measurements/10.1117/1.OE.55.7.074110.full |access-date=November 20, 2025|doi-access=free }}</ref> The interacting waves of the two beams constructively or destructively interfere, which can be measured via interferometry to visualize microscopic objects.
Interference microscopy enables visualization and measurement of transparent or nearly transparent specimens, such as living cells or thin films, without the need for staining by converting phase shifts in light into differences in amplitude or contrast visible to the observer.
In materials science and surface metrology, interference microscopy is also widely used to characterize surface topography and quantify micro-scale surface irregularities, with vertical resolutions on the order of nanometers achievable through multi-beam interference techniques.<ref name="slim_review">{{cite journal |author1=Xi Chen | author2 = Mikhail E Kandel | author3 = Gabriel Popescu|title=Spatial light interference microscopy: principle and applications to biomedicine |journal=Nature Reviews Methods Primers |date=May 4, 2021 | volume = 13 | issue = 2 | pages = 353–425 | doi = 10.1364/AOP.417837 | pmid = 35494404 | pmc = 9048520 | arxiv = 2012.08801 | bibcode = 2021AdOP...13..353C }}</ref>
Types include: * Classical interference microscopy * Differential interference contrast microscopy * Fluorescence interference contrast microscopy * Interference reflection microscopy
==See also== * Phase contrast microscopy
==References== {{reflist}}
Category:Microscopy
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