Fig. 1. System schematic of proposed PM-PI-OCT system. C, collimator; CP, circular polarizer; DG, diffraction grating; FC, fiber coupler; GVS, galvanometer scanner; L, lens; LP, linear polarizer; LSC, line-scan camera; M, mirror; MS, mating sleeve; PC, polarization controller; PMF, polarization maintaining fiber; S, sample; SLED, superluminescent light-emitting diode.

Fig. 2. Structure of PM fiber and obtained OCT image using PM fiber. (a) Illustration of the PM-fiber structure and axes. (b) Representative obtained OCT image. (c) A-scan profiling results along the yellow dashed line in (b).

Fig. 3. Customized mount for measuring the polarization artifact according to the angle. (a) Illustration of customized mount combined with SM and PM fiber. (b), (c) Photographs of the 3D printed mount with and without the cover. (d)–(g) Photographs of the representative cases with different angles.

Fig. 4. System schematic of a dual-OCT system for comparing performance of the proposed PM-PI-OCT and conventional OCT. C, collimator; CP, circular polarizer; DG, diffraction grating; FC, fiber coupler; GVS, galvanometer scanner; L, lens; LP, linear polarizer; LSC, line-scan camera; M, mirror; MS, mating sleeve; OS, optical switch; PC, polarization controller; PMF, polarization maintaining fiber; S, sample; SLED, superluminescent light-emitting diode; SMF, single-mode fiber.

Fig. 5. Before and after compensation of PM-PI-OCT images using IR-card as a sample. (a) B-scan image before compensation. (b)–(d) FFFF, FFSS, and SSSS state images after compensation using our proposed method.

Fig. 6. Quantitative polarization state variance robustness of SM-OCT and PM-PI-OCT for five different rotation angles. (a), (g) Representative rat retina images of SM-OCT and PM-PI-OCT, respectively. (b)–(f) Intensity histogram of SM-OCT at different angles with averaged value and standard deviation. (h)–(l) Intensity histogram of PM-PI-OCT at different angles with averaged value and standard deviation. (m), (n) SSIM and histogram comparing plot. (o), (p) Count graphs of SSIM and histogram comparing. (q) Correlation graph between SSIM and histrogram comparing.

Fig. 7. Quantitative polarization state variance robustness of SM-OCT and PM-PI-OCT for randomly changed rotation angles. (a)–(e) Selected five SM-OCT images. (f)–(j) Selected five PM-PI-OCT images. (k), (l) Count graphs of averaged intensity of each frame and averaged intensity differences for both SM-OCT and PM-PI-OCT. (m) Correlation graph between averaged intensity and intensity difference. (n) Averaged intensity and intensity difference plot with averaged value and standard deviation. (o), (p) Count graphs of SSIM and histogram comparing. (q) Correlation graph between SSIM and histogram comparing. (r) SSIM and histogram comparing plot with averaged value and standard deviation.

Fig. 8. In-vivo human retina images using SM-OCT and PM-PI-OCT for randomly changed rotation angles. (a)–(e) Selected five SM-OCT images. (f)–(j) Selected five PM-PI-OCT images. SNR, signal-to-noise ratio.