Table 1.

Comparisons of the various OCT technologies.

	TD-OCT	SD-OCT	SS-OCT
1. Commercial Availability	1996 [4]	2006 [4]	2012 [4]
2. Principle of Operation	A beam splitter splits incident light into a reference wavelength which is adjusted for different depths while the sample light is reflected from the observed tissue and recombined at a sensor to give a single profile of the tissue [5].	Based on FD-OCT. It has similar principles to TD-OCT, but the sensor is upgraded to a spectrometer to split the reflected light into wavelengths (λ) using a diffractor. A combination of the individual images provided by the λs produces a Fourier transform to obtain depth information (A-scan) [6].	Also based on FD-OCT like SD-OCT. It possesses a sweeping tunable laser as its light source. A photoreceiver transduces the relayed signals into noise (images) [7].
3. Bandwidth	20 nm [8]	150 nm [8]	~1040–1080 nm [8]
4. Wavelength Frequency	810 nm [8]	840 nm [8]	~1050 nm [9]
5. Axial resolution	8–10 µm [9]	5–7 µm [9]	5.3 µm [10]
6. Scan Speeds	400 A-scans per second [11]	20,000–52,000 A-scans per second [11]	100,000–236,000 A-scans per second [11,12]