Fig. 1. One-dimensional ¹H stray field (STRAFI) image of the resolution test phantom, made from alternating Perspex and glass discs each of 50 mm diameter. Thickness of each glass spacer is given above the appropriate minimum in the profile. The slice separation (step size) is 90 µm. The intensity profile is the sum of the first five echoes of the STRAFI echo train, with one point per echo.