An SS-OCT instrument is used in this study, as depicted in Fig. 1. The SS is from Axsun Technologies Ltd., Billerica, Massachusetts (1060-nm swept laser engine) having a central wavelength of 1050 nm, a sweeping range of 106 nm (measured at 10 dB), an average output power of 16 mW, and a sweeping rate of 100 kHz. A depth resolution determined by the SS of 12 μm in air was experimentally measured. Light from SS is split into a sample arm and a reference arm by the directional coupler DC1. In the sample arm, to convey light to and from the object, a pair of orthogonal galvo-scanner mirrors (GXY) is used. The combination of two microscope objectives (MO1 and 2) determines a lateral resolution of . The optical power on the sample is 3.6 mW. In the reference arm, light is directed via the microscope objectives MO3, 4 and the flat mirrors M1, 2 toward the directional coupler DC2, where it interferes with light originating from the sample. The DC2 output signals are sent to a balance photodetector BPD (Thorlabs, Newton, New Jersey, model PDB460C, bandwidth of 200 MHz). The output of the photodetector is digitized by a 12-bit analog-to-digital acquisition card (Alazartech ATS9350, Montreal, Canada), while an “in-house” Labview (National Instruments, Austin, Texas) created software is used to produce, display, and record the images. The lateral size of the 3-D images, determined by the amplitude of the voltages applied to the galvo-scanners and the focal length of MO1, is , while their axial size, determined by SS, is 3.7 mm (measured at 6 dB). The system is able to produce B-scan images (cross-sectional images of the sample) at a frame rate of 100 Hz. 3-D reconstructed images could then be produced, which are of . Inspection of the volume can be performed either along B-scans or C-scans.