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The large number of missions associated with ESA’s Copernicus program has necessitated several new image sensor designs for earth observation (or living planet) applications as each instrument needs to be highly optimized. Whilst the majority of these sensors have utilised CCD technology, the use of CMOS is starting to increase. New CCD designs and technology trends for hyperspectral applications such as Sentinel 4, Sentinel 5, Sentinel 5 precursor (TropOMI), Flex and 3MI are described. In these the sensor design has been optimized to provide highest possible signal levels with lowest possible noise in combination with higher frame rates and reduced image smear. CMOS sensors for MTG (Meteosat Third Generation) and METImage are then described. Both use extremely large pixels, up to 250μm square, at high line rates. Radiation test data and key performance measurements are shown for MTG and for a test device that has been made for METImage. Finally, newer developments including back-illumination and means for achieving a TDI function in standard-processed CMOS are briefly described.

The sensor design for Hyperspectral observation is significantly different to many other imaging applications and the various requirements are discussed. An early programme is the MERIS (Medium Resolution Imaging Spectrometer) instrument on ENVISAT, which has been producing high quality Hyperspectral images for the last 7 years. The requirements for MERIS originally led to the development at e2v of both back-thinning technology, to meet the spectral requirements, and the manufacture of devices with a graded antireflection coating, to fully optimize the QE at every spectral band. A number of other hyperspectral missions are being planned or in preparation. For example Sentinel 3 is to be an almost direct repeat of the MERIS instrument and will be followed by Sentinel 4 and 5. In the future as the technology matures it is likely that Hyperspectral missions will tend to use CMOS sensors rather than CCD. CMOS sensors have a number of potential advantages for Hyperspectral imaging and if these can be successfully exploited then enhanced performance would result. The design of a CMOS sensor is discussed that is targeted at Hyperspectral application to give fully optimized performance at all spectral bands.

The ESA cornerstone mission GAIA will perform astrometric, photometric and spectroscopic measurements and is due for launch in 2010 into L2 orbit. The astrometric telescope system will catalogue the position of over 10 9 objects down to 20 th magnitude and perform broadband photometry. The spectroscopic telescope will provide narrow-band photometry and feed a Radial Velocity Spectrometer which will accurately determine the radial velocities of objects down to 17-18 magnitude. This paper discusses the characteristics of the detectors envisaged for the focal plane of the RVS instrument.

e2v technologies has demonstrated capability in the supply of state-of-the-art CCDs for large area scientific focal planes. We discuss technical developments and lessons learnt from the manufacture and supply of large-format CCDs. Several large mosaics have now been built or are under construction, using e2v sensors- these include CFHT Megacam, ESO VST, SAO Megacam, Kepler, and GAIA. Design, assembly and operational issues are presented.

The ESA cornerstone mission GAIA will perform astrometric and photometric measurements on one billion objects, and is due for launch in 2010 into L2 orbit. The key astrometric focal plane will comprise over 180 large area CCDs with a focal surface of about 0.5m2. The 45x60mm2 CCDs for the focal plane will include technical features new to CCDs. This paper will discuss the characteristics of these devices, including the measures to improve the radiation hardness of the technology.