MIRFI: A Mid-Infrared Fabry-Perot Imager

We have constructed a mid-infrared Fabry-Perot imager (MIRFI) at Nagoya University. At present, MIRFI is tuned to the 12.813 mu m fine-structure line of [Ne II], and it provides line images with a spectral resolving power of R similar to 2500 over a 5x5 pixel Si:P photoconductive detector array. This array has a plate scale of 1.3" pixel(-1) and a field of 8"x8" when mounted on the 3-m NASA Infrared Telescope (IRTF). The Fabry-Perot driving mechanism utilizes solenoid magnets and is cooled by liquid He. MIRFI achieves background-limited performance, and its noise equivalent line flux sensitivity is currently 1.6x10(-20) W cm(-2) pixel(-1) per spectral resolution element for a 17-s on-source integration on the IRTF. Future upgrade plans for MIRFI are also described.