3D: a new generation imaging spectrometer

3D, the next generation near-IR spectrometer developed at the MPE, offers, in a single integration, the opportunity to image an 8" x 8" field with a pixel scale of 0.5" or 0.3" across the entire K- or H-band simultaneously at a spectral resolution of R equals 1000 or R equals 2000 (K). Combining the advantages of imaging and spectroscopy increases the observing efficiency on small extended objects (e.g., galactic nuclei) by such a large factor over existing grating or Fabry-Perot spectrometers that subarcsecond near-IR spectroscopy on faint Seyferts, starbursts, quasars, or distant galaxies clusters becomes feasible for the first time on 4 m class telescopes. 3D, including a NICMOS III FPA at 25 e^-/single read, has been successfully operated at telescopes such as the 4.2 m WHT, 3.5 m Calar Alto, and 2.2 m La Silla. An additional tip-tilt seeing corrector for 3D called ROGUE correcting on up to 18th mag stars at 4 m-class-telescopes was successfully commissioned in the summer of 1994. The optical and electronic design of 3D as well as recent results are presented.