2.5 Fourier-Domain Low-Coherence Interferometry Still, the cross-correlation component is the desired part. The FWHM of the DC artifact is only one coherence length wide, however, the signal amplitude is much higher than another two components. How to remove it ? Record the amplitude of the spectral interferometric signal with reference reflector but no sample present, […]
2.1 Introduction About the A-scan: the electronic signals detected by the photoreceiver are processed as A-scan, which represents the reflectivity profile at the specific focal spot of the sample beam. About B-scan: multiple A-scans are acquired by sweeping in the lateral direction, and thus a two-dimensional cross-sectional image is created. C-scan: en face images at […]
If you are interested in this paper Dynamic full field optical coherence tomography: subcellular metabolic contrast revealed in tissues by interferometric signals temporal analysis, please find it here [1]. In this paper, an new imaging method called dynamic full field optical coherence tomography (D-FFOCT) is proposed, which features in subcellular metabolic contrast in fresh ex […]
The derivation is quite good in Chapter 9 of the book Biomedical Optics: Principles and Imaging [1] by Lihong V. Wang, so I’m not going to repeat again. Here I will add some notes which might be helpful during the derivation. The formula of coherence length is directly given without specific derivation (Eq. 9.15). {l_c} […]
The axial resolution of OCT is determined by the measurement resolution for echo time delay of light. To derive the formula of axial resolution mathematically, I turn to Chapter 5 of the book Optical Coherence Tomography – Principles and Applications [1]. 1. Monochromatic source To start with time domain OCT, we first refer to a […]
If you are interested in the original paper Optimal operational conditions for supercontinuum-based ultrahigh-resolution endoscopic OCT imaging by Wu Yuan, please refer to Ref. [1]. 1. General concepts The laser noise mainly comes from two sources [2]: quantum noise, which is related with spontaneous emission in the gain medium. technical noise, including excess noise of […]
This is the note for the book Optical Coherence Tomography-Technology and Applications [1]. 1.1 Introduction Raster scanning: the rectangular pattern of image capture and reconstruction in television. Although often a great deal faster, it is similar in the most general sense to how one’s gaze travels when one reads lines of text. Optical biopsy: examination […]
1. Signal Introduction: OCT Acquisition and Multiplexing 1.1 How Full field OCM works? At a specific depth, the interferometric light on the cross-sectional plane of the sample is detected by FFOCTM. The two-dimensional slice is thus produced. It means FF-OCM creates en face images Q: En face OCT imaging? A: A simple tutorial for En […]
Deep learning for ophthalmology OCT Deep learning in glaucoma with optical coherence tomography: a review Full field OCT After searching the OSA Publishing, pubmed, web of science and google scholar, I see the earliest paper related with full-field OCT appear in 2002 by Arnaud Dubois, and there are more than 200 related research papers. Among […]
You can find this paper here if you are interested. Traction force microscopy (TFM) plays an important role to quantify cellular traction forces (CTFs), which help access the physiological processes and diseases. Here, traction force optical coherence microscopy (TF-OCM) is proposed to reconstruct 3D CTFs quantitatively in scattering media with minute-scale temporal sampling. In this […]