Fig. 2.

HRF imaging resolution. Root mean square (RMS) spot diagrams calculated in ZEMAX at image plane (IMA) of (a) on-axis and (b) field-edge imaging points. The on-axis spot diagram is diffraction limited ($8.7\mu \mathrm{m}$), while rays at the edge of the field focus to a $27.8\text{-}\mu \mathrm{m}$ spot (RMS). (c) HRF image of a high resolution USAF target. The system is capable of resolving group 8, element 2 with 26.4% contrast, consistent with the Rayleigh criterion. This corresponds to an imaging resolution of $3.5\mu \mathrm{m}$. The inset shows groups 7 to 9 in greater detail.