Advanced Detectors, Systems, & Nanoscience
On-Sky Observation with Broadband Detectors
MDL recently developed and delivered broadband silicon CCD arrays for the Wafer Scale camera at Prime focus (WaSP) instrument, an upgrade to the current prime focus imager at Palomar Observatory’s200-inch Hale telescope. These dedicated 4-megapixel guide and focus CCDs are required to maintain both telescope tracking (during long exposures) and focus (during a night’s observing). JPL’s superlattice-doping technology combined with multilayer AR coatings prepared by ALD delivers enhanced blue sensitivity with high quantum efficiency optimized over 320–1000 nm. This is highly advantageous when observing through short-wavelength filters where suitable guide stars (for tracking and guiding) become faint and CCD throughput typically drops. These 2kx2k, 15-µm pixel deep-depletion CCD arrays are designed by STA and fabricated at Teledyne DALSA. Custom packaging and wire-bonding techniques were designed at JPL to meet the special needs of the WaSP instrument for a closely packed camera.