## 1 Introduction
The polarization states' alignment with the optical axis of the tissue also affects the PSOCT system's polarization sensitivity [25]. The system structure is complex and difficult to implement, and the imaging algorithm is also intricate. These problems negatively impact the imaging speed of the system and hinder its integration. Therefore, most of the current mainstream PSOCT systems use a single-input-state PSOCT system based on circularly polarized light [26]. Errors in circularly polarized light are inevitable due to conditions such as optical components. To address this issue, a method that involves positioning a polarization controller in the source, sample, reference, or detection arms, and calibrating a single fiber transformation to restore incident light to circular polarization was proposed [27]. However, this approach is effective only when the polarization controller is aligned and the fibers remain stationary, making it unsuitable for flexible sample arms or endoscopy. These errors in the polarization state can be misinterpreted as birefringent properties of the sample, resulting in imaging bias. Many studies have proposed calibration methods, as manual adjustment is limited. Numerical calibration can be applied to circularly polarized light to reduce errors, as proposed by [PERSON] et al. for the dithering error of PSOCT [28]. However, the polarization sensitive imaging quality, or the system's sensitivity, is low because the incident circularly polarized light is not perfectly circular in practice. Currently, the mainstream approach involves using circularly polarized light as the incident light. Since its introduction by [PERSON] et al. in 1992, PSOCT has commonly used circularly polarized light in single-input state configurations [15]. The coherent interference of polarized light is influenced by its polarization states. Samples may exhibit different polarization characteristics in different directions. When linearly polarized light is orthogonal or parallel to the optical axis of the sample, some information may be lost. In using circularly polarized light, the impact of the sample's inherent polarization characteristics on the measurement results can be overcome, ensuring that the measurement results are not affected by sample polarization. Circularly polarized light also enables the reflectometer to be insensitive to the rotation of the sample axis. A quarter-wave plate (QWP) can be used to convert linearly polarized light into circularly polarized light. This requires the angle between the fast axis direction of the wave plate and the polarization direction of the linearly polarized light to be 45\({}^{\circ}\). When this angle deviates from 45\({}^{\circ}\), the linearly polarized light, after passing through the QWP, will transform into elliptically polarized light, which approximates circularly polarized light. Manual adjustment to a certain degree usually introduces errors. This means that the light incident onto the sample is not perfect circularly polarized light, leading to a decrease in system sensitivity and a degradation in imaging quality. To address the aforementioned issues, we propose a robust numerical correction method to further enhance imaging quality. Specifically, the interference fringes are inverted into the complex plane through an inverse Fourier transform, and new equal and orthogonal vectors are reconstructed in the complex plane as new data for imaging. We verified the effectiveness of this method in vitro. For chicken breast, pork, and beef, the signal-to-noise ratio of the system was improved by 24, 26, and 11 dB compared to the results before correction.