The Canarias InfraRed Camera Experiment (CIRCE) will be the only near-infrared instrument for the Gran Telescopio Canarias (GTC) 10.4-meter telescope with polarimetric capabilities. Both, image and spectroscopic polarimetry as well as high time resolution readout and lower spectral resolution will complement the capabilities of EMIR. Its 2048x2048 HawaiiII-2 detector and its aspheric optics described by Edwards et al (2007) will provide a pixel scale resolution of 0.1 arcsec/pixel in 3.4' FOV in the range of 1-2.5mm. Low spectroscopy resolutions of 410 (at 1.25mm) and 725 (at 2.20mm) will be avalaible in the range 1.25- 2.40mm. CIRCE will reach this depth (see below image) in Ks with an on-source integration time of less than 1 minute, slightly faster than NIRC/Keck with 25x greater FOV and 50% faster then NIRI/Gemini with 3x greater FOV.
CIRCE is an asymmetric reflective system except for the entrance windows, filters, grisms and the polarimetric components. Its 8 diamond-turned aspheric mirrors offer both excellent throughput and image quality. We assure low-level background noise from the telescope and instrument by inserting the optical elements in a cryostat with liquid nitrogen. The optical quality analysis Edwards et al (2005) shows that images are seeing-limited with less than 0.25 arcsec. The team of the instrument is as follow Stephen Steve Eikenberry (PI), Antonio Marin Franch (software), Michelle Edwards (optics), Nestor Lasso Cabrera (electronics), Miguel Charcos Llorens (mechanics). Engineers in the department are an important support for the instrument conception: Kevin T. Hanna (electronics), Jeffrey A Julian (mechanics) and Steven Raines (system engineering).