Multichannel signal detection of optical coherence tomography with different frequency bands

Summary form only given. Recent development of optical coherence tomography (OCT) has shown great promising applications for noninvasive and contactless imaging of subsurface soft tissues. However, better image quality and greater depth of penetration are always advantageous for clinical applications. A new 8-channel array detecting optical coherence tomography (ADOCT) system has been built with the advantages of sensitivity improvement and speckle noise reduction. Multifrequency compensation techniques have been applied for demodulating array signals at different frequency bands. As the results, the reconstructed in vivo ADOCT images are capable to resolve the information from not only the near-optical field (<1 mm) but also the far-field (from 1 mm to 2 mm) of the highly scattered tissues, such as human skins. An in vivo ADOCT image of human skin tissue with a penetration of 1.8 mm has been achieved as showing in Fig. 1. Detailed structure information from different layers of epidermis and dermis, sweat gland, as well as capillaries in dermis can be observed clearly from the ADOCT images. Furthermore, some in vivo cross-sectional OCT images of human nailfolders have also been compared with the traditional histological images. The results indicate that OCT images provided good correlation with the histology.