Editing Michelson interferometer (section)

===Miscellaneous applications===
[[File:SDOHMIdoppler sunspot.png|thumb|350px|Figure 7. Helioseismic Magnetic Imager (HMI) dopplergram showing the velocity of gas flows on the solar surface. Red indicates motion away from the observer, and blue indicates motion towards the observer.]]
Fig.&nbsp;7 illustrates use of a Michelson interferometer as a tunable narrow band filter to create [[dopplergram]]s of the Sun's surface. When used as a tunable narrow band filter, Michelson interferometers exhibit a number of advantages and disadvantages when compared with competing technologies such as [[Fabry–Pérot interferometer]]s or [[Lyot filter]]s. Michelson interferometers have the largest field of view for a specified wavelength, and are relatively simple in operation, since tuning is via mechanical rotation of waveplates rather than via high voltage control of piezoelectric crystals or lithium niobate optical modulators as used in a Fabry–Pérot system. Compared with Lyot filters, which use birefringent elements, Michelson interferometers have a relatively low temperature sensitivity. On the negative side, Michelson interferometers have a relatively restricted wavelength range, and require use of prefilters which restrict transmittance. The reliability of Michelson interferometers has tended to favor their use in space applications, while the broad wavelength range and overall simplicity of Fabry–Pérot interferometers has favored their use in ground-based systems.<ref name=Gary2004>{{cite web|last1=Gary |first1=G.A. |last2=Balasubramaniam |first2=K.S.|title=Additional Notes Concerning the Selection of a Multiple-Etalon System for ATST|url=http://atst.nso.edu/files/docs/TN-0027.pdf |date=11 June 2004 |publisher=Advanced Technology Solar Telescope|access-date=29 April 2012|url-status=dead|archive-url=https://web.archive.org/web/20100810222938/http://atst.nso.edu/files/docs/TN-0027.pdf|archive-date=10 August 2010}}</ref>

[[File:OCT B-Scan Setup-en.svg|thumb|350px|right|Figure 8. Typical optical setup of single point OCT]]
Another application of the Michelson interferometer is in [[optical coherence tomography]] (OCT), a medical imaging technique using low-coherence interferometry to provide tomographic visualization of internal tissue microstructures. As seen in Fig.&nbsp;8, the core of a typical OCT system is a Michelson interferometer. One interferometer arm is focused onto the tissue sample and scans the sample in an X-Y longitudinal raster pattern. The other interferometer arm is bounced off a reference mirror. Reflected light from the tissue sample is combined with reflected light from the reference. Because of the low coherence of the light source, interferometric signal is observed only over a limited depth of sample. X-Y scanning therefore records one thin optical slice of the sample at a time. By performing multiple scans, moving the reference mirror between each scan, an entire three-dimensional image of the tissue can be reconstructed.<ref name=Huang1991>{{cite journal|last=Huang|first=D.|display-authors=4 |author2=Swanson, E.A. |author3=Lin, C.P. |author4=Schuman, J.S. |author5=Stinson, W.G. |author6=Chang, W. |author7=Hee, M.R. |author8=Flotte, T. |author9=Gregory, K. |author10=Puliafito, C.A. |author11=Fujimoto, J.G.|title=Optical Coherence Tomography|journal=Science|date=1991|volume=254|issue=5035|doi=10.1126/science.1957169|url=http://stuff.mit.edu:8001/afs/athena/course/2/2.717/OldFiles/www/oct_fujimoto_91.pdf|access-date=10 April 2012|pmid=1957169|bibcode=1991Sci...254.1178H|pages=1178–81 |pmc=4638169}}</ref><ref name=Fercher1996>{{cite journal|last=Fercher|first=A.F.|title=Optical Coherence Tomography|journal=Journal of Biomedical Optics|date=1996|volume=1|issue=2|pages=157–173|url=http://otg.downstate.edu/downloads/2008/spring08/refsbmi/oct/fercher.pdf|access-date=10 April 2012|bibcode=1996JBO.....1..157F|doi=10.1117/12.231361|pmid=23014682|archive-url=https://web.archive.org/web/20180925131609/http://otg.downstate.edu/downloads/2008/spring08/refsbmi/oct/fercher.pdf|archive-date=25 September 2018|url-status=dead}}</ref> Recent advances have striven to combine the nanometer phase retrieval of coherent interferometry with the ranging capability of low-coherence interferometry.<ref name=Olszak>{{cite web|last=Olszak|first=A.G.; Schmit, J.; Heaton, M.G.|title=Interferometry: Technology and Applications|url=http://www.bruker-axs.com/fileadmin/user_upload/PDF_2011/application_notes/Interferometry_Technology_and_Applications_SOM_AN47.pdf|publisher=Bruker|access-date=1 April 2012}}{{Dead link|date=April 2020 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

Others applications include [[delay line interferometer]] which convert phase modulation into amplitude modulation in [[DWDM]] networks, the characterization of high-frequency circuits,<ref>Seok, Eunyoung, et al. "A 410GHz CMOS push-push oscillator with an on-chip patch antenna." 2008 IEEE International Solid-State Circuits Conference-Digest of Technical Papers. IEEE, 2008.| https://doi.org/10.1109/ISSCC.2008.4523262</ref><ref>{{cite journal | last1 = Arenas | first1 = D. J. | display-authors = etal | year = 2011 | title = Characterization of near-terahertz complementary metal-oxide semiconductor circuits using a Fourier-transform interferometer | journal = Review of Scientific Instruments | volume = 82 | issue = 10| pages = 103106–103106–6 | doi = 10.1063/1.3647223 | pmid = 22047279 | bibcode = 2011RScI...82j3106A | osti = 1076453 }}</ref> and low-cost THz power generation.<ref>Shim, Dongha, et al. "THz power generation beyond transistor fmax." RF and mm-Wave Power Generation in Silicon. Academic Press, 2016. 461-484. {{doi|10.1016/B978-0-12-408052-2.00017-7}}</ref>