Figure 4From: An innovative approach to near-infrared spectroscopy using a standard mobile device and its clinical application in the real-time visualization of peripheral veins An image from the prototype (above) and an associated cross-sectional ultrasound image confirming the presence of a pair of veins below the skin surface. A (0.40 cm) and B (0.22 cm) represent the depth of the veins as identified with the ultrasound device.Back to article page