The spectrum has peaks and troughs, the period of the modulation being proportional to the OPD in the interferometer. SB-OCT is based on the demodulation output of the optical spectrum of the low coherence interferometer. This is like the TD-OCT procedure, but instead of scanning the OPD the charges on the array are read in the spectrometer in SB-OCT or by tuning the frequency of the laser in SS-OCT. The second involves using a swept source (SS) and the processing unit which employs a photodetector. The first involves using a combination of broadband optical source and the processing unit which utilizes a spectrometer. SD-OCT refers to the spectral interrogation of the spectrum at the interferometer output. Spectral domain optical coherence tomography Another method of performing TD-OCT is en face OCT, which involves taking one-dimensional reflectivity scans (T-scans), with the end image being comprised of many T-scans. A cross-section image is obtained by taking adjacent scans of the object this is also known as axial TD-OCT. OCT was invented by the addition of a transversal scanner to a low coherence interferometer to scan the beam over the object laterally. The OPD can be used to work out which layers within an object can be imaged. The optical path difference (OPD) is obtained by subtracting the length of the reference path from the length of the object path. The processing unit performs the interference of light between the reference beam and the beam returned from the object of interest, and it also processes and analyzes the interference signal.

A microscopy interface optics is used to convey light from the splitter to and from the object of interest and up to a processing unit.

A reference mirror and an optical splitter are used to produce a reference beam. COVID-19 may cause brain shrinkage in some peopleĪ TD-OCT setup uses an optical light source and an interferometer.Researchers explore the link between immunoglobulins and blood profile in severe SARS-CoV-2 patients.Study shows BCG vaccination reduces SARS-CoV-2-induced lung inflammation in hamsters.

Optical coherence tomography