Fig. 2.

(A) Axial point spread function without and with digital dispersion compensation demonstrating an axial resolution of 25.7 μm. (B) Signal to noise ratio (SNR) computed as described in operational SNR Eq. (1) as a function of imaging depth. The inset displays representative M-mode images from a mirror without (left) and with (right) dispersion compensation at a depth of z = 4.2 mm. (C) Beam width variation as a function of the distance away from the catheter tip. Inset: representative image of a point-like scatterer used in these measurements (distance of 4.4 mm)). (D) Representative Gaussian-fitted profile of the normalized intensity of the transverse point spread function at an axial distance of 4.4 mm.