CFHT operating manual - Homepage Usask

ESPaDOnS: picture gallery http://webast.ast.obs-mip.fr/magnetisme/espadons_new/gallery.html
detailed view of the exposure meter with the main collimator in the background; the small pickup
mirror reflecting off photons towards the exposure meter optics, as well as the exposure meter shutter, are clearly
visible;
detailed view of the 204mm wide and 408mm long R2 diffraction grating in its mount (inspired from
the feros design); the grating is tilted downwards (with 6 invar pins glued on its rear and side surfaces to hold it against
gravity) to minimise dust accumulation on the diffracting surface, and semi circular baffles are included in the bottom
part of the mount to reduce straylight from the grating to a minimum;
detailed view of the transfer collimator in its mount; the side panel of the main collimator and part
of the mirror itself is also visible on the left of the image (the rest of the main collimator hiding behind the black baffle);
global view of the last section of the spectrograph optics; photons reflected off the transfer
collimator (not visible here) are cross-dispersed by the prism train (in its black parallelepipedic cage with two handles
on top, on the right of the image) and concentrated by the large dioptric camera (black cylinder with a hook on top of it,
in the middle of the image) before being collected onto the ccd detector inside its dewar and vaccuum vessel (pink
cylinder on the left of the image); the thin disc between the prism train and the dioptric camera is the motorised
hartmann mask, used to focus automatically the spectrograph;
detailed view of the cross-dispersing prism train within its mount; the whole train can be rotated
manually (when aligning the spectrograph) with the newport stage included in its base;
detailed view of the ccd dewar with its attendant electronics installed on top of it and the
permanent evacuated fill/exhaust pipe coming from behind (with further insulation added around it, forming a
yellowish horizontal cylinder on the right side of the image); the dewar mount was designed so that the ccd tilts could be
adjusted to fit the instrument focal plane to within better than 1 arcmin;
close-up view of the pressure sensor (accurate to within 0.01mbar) installed within the
spectrograph; note the temperature sensor (thin horizontal rod) mounted on the base of the transfer collimator (upper
left corner of image); three such temperature sensors (accurate to within 0.01deg) are installed throughout the
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