Current instrument sand future plans for new instrumentation for the Keck Observatory are reviewed. As is widely known, both 10-meter telescopes are in full operation and each has a significant complement of scientific instruments. Keck II has a working adaptive optics system and a similar module is under construction for Keck I in preparation for combining the beams in the Keck Interferometer. Recently, Keck II received two new instruments, ESI - which is a CCD-based faint-object spectrograph, and NIRSPEC, a cryogenic high- resolution near-IR spectrograph. The existing LRIS spectrograph is due to an upgrade to provide a blue- sensitive channel to complement the current red channel. DEIMOS, a multi-object spectrograph and NIRC2, a diffraction-limited IR camera are nearing completion. Future plans include detector upgrades, instruments for integral field and wide-field spectroscopy, interferometry and laser guide stars.

The paper deals with the global approach in place at ESO to optimize observing efficiency at the VLT. It involves not only the telescopes and their associated instrumentation, but as a mater of fact the whole observing process from proposals to data distribution. The ten main avenues pursued to reach that goal are presented, and early experience at Paranal Observatory reported. The need for continuous renewal of instrument complements at large telescope facilities is stressed.

The Subaru telescope had its astronomical first light at the Cassegrain focus in January 1999. Fine tuning of the telescope and commissioning of the seven open-use instruments at four foci of the Subaru telescope are in progress. An overview of the updated status of the observational instruments is presented with reference to papers addressed during this series of conferences. General status of the Subaru telescope, the plan for the open use of the instruments, and the scope for the second generation instruments under investigation are also reported.

Building instruments suitable for the new 8-10 m class of telescopes has been a major challenge, as specifications tighten, costs, scientific demands, and expectations grow, all while schedules remain demanding. This report provides a top level description of the status of various elements in the Gemini instrument program, and touches on some of the common problems the various teams building Gemini instruments are having. Despite these challenges, Gemini anticipates harvesting great scientific rewards from the combination of its Observatory facilities and exciting complement of scientific instruments.

We are building a Multi-Object Double Spectrograph for the Large Binocular Telescope. The main themes of our planned research with the instrument are the formation and evolution of galaxies and their nuclei and the evolution of large- scale structure in the universe, although we expect that the spectrograph will be used for many other varieties of programs as well. The science goals for the instrument dictate that it have the highest possible throughput form 320 to 1000 nm, spectral resolutions of 10³ to 10⁴, and multi-object capability over an approximately 6 foot field. Our design is highly modular, so future upgrades should be straightforward.

The Hobby-Eberly Telescope (HET) is a revolutionary large telescope of 9.2 meter aperture, located in West Texas at McDonald Observatory. HET has been constructed by a consortium of US and German universities for about 16 million dollars. First light was obtained on December 11, 1996, HET was dedicate don October 8, 1997, and early scientific operations started on October 8, 1999. The HET operates with a fixed segmented primary and has a tracker which moves the four-mirror corrector and prime focus instrument package to track the sidereal and non-sidereal motions of objects. Here we describe the current performance of the HET relative to its goals.

The presentation summarizes the status of the first generation of instruments for the 10-m Spanish Telescope, GTC. The GTC is planned to have its first light at the end of 2002, and to be operating at the end of 2003. The management plan at the Project Office, PO, for the procurement of the instruments is presented.

We review the characteristics of SALT and discuss the major science drivers, both of which will decide the choice of a fist-light instrument package. Current science drivers call for instrumentation similar to that of the Hobby-Eberly Telescope, on which SLAT is closely modeled, with fiber-fed and direct spectroscopy in the visible/near-IR being the major observational mode delivering the best astrophysical returns. The suite will include multi-object spectroscopic capability over a continuous wavelength range of at least 400 nm to 1300 nm, with possible extended capabilities to the blue and near-IR. Factors which will decide these limits are discussed, which include mirror coatings and fiber transmission. Other specific science drivers, which may influence instrument choice or design, include photometry, imaging spectroscopy and spectropolarimetry. Possibility exist for different or novel approaches to instrument designs. Together with potential enhancements of the telescope design, these will have some impact on instrument choice. The nature of the first light instrument suite is currently under discussion and will probably be decided by late-2000.

Five SOAR instruments are being designed for high-resolution imaging/imaging spectrophotometry across the isokinetic field and queued/remote observing. Wavefront tilt will be sensed in instruments and corrected by jittering M3. SDSU-2 'Leach' controllers under LabVIEW will operate most detector arrays. All optical instruments emphasize high UV throughput, and will use pairs of UV-enhanced MIT/LL 2 by 4 K CCDs. The University of Sao Paulo may provide a 1500- element integral field lenslet array that is fiber-coupled to a compact spectrography. VPH gratings will be used in this instrument and in the multi-slit spectrometer from the University of North Carolina at Chapel Hill. CTIO will provide an optical mosaic imager with 'trombone'-style ADC, and may also upgrade their IRS with its large complement of existing gratings to a 1 by 1K Hawaii array. Michigan State University may build a 4 by 4K near-IR imager with tunable Lyot filter. Most instruments will be clustered at Nasmyth ports where payload totals 4400 kg. Facility units will allow calibration while another instrument is doing science. The baseline for mechanism control is LabVIEW under Linux in a Compact PCI chassis that is fiber-linked by MXI-3 to a dedicated PC.

FORS is an all dioptric focal reducer designed for direct imaging, low-dispersion multi-object spectroscopy, imaging polarimetry and spectropolarimetry of faint objects. Two almost identical copies of the instrument were built by a consortium of three astronomical institutes under contract and in cooperation with ESO. FORS1 was installed in September 1998 and FORS2 in October 1999 at the Cassegrain foci of the ESO VLT unit telescope nos. 1 and 2. FORS1 is in regular operation since April 1999. Regular observation with FORS2 are scheduled to begin in April 2000.

Faint object camera and spectrograph, FOCAS, is a Cassegrain optical instrument of Subaru telescope. It has a capability of 6 arcmin FOV direct imaging, low resolution spectroscopy, multi-slit spectroscopy as well as polarimetry. Only the imaging mode has been available so far. The overall design, the observing functions, and the preliminary performance verifications of FOCAS will be presented.

The Gemini Multiobject Optical Spectrographs were designed to exploit the exceptional image quality anticipated form both the active and adaptive optics systems. High mechanical stability and repeatability and efficient reconfiguration and calibration were emphasized in the design, as well as the usual requirements of obtaining excellent image quality, high optical throughput and low optical distortion. In addition, an active flexure compensation system is used to assist in achieving a primary goal of attaining velocity accuracies of 2 km/s per spectrum in multiobject mode at the highest spectral resolution. Although the field is modest, small pixels are used to fully sample images as small as 0.2 inch and 28.3 million pixels will be recorded by the detector mosaic which consists of three 2048 * 4608 EEV CCDs. In this paper, results from extensive tests made during integration and testing of GMOS N components demonstrate that the design requirements are being met.

LAMOST is a special Schmidt telescope of 4 meters aperture. It will be located in Xinglong station at Beijing Astronomical Observatory, China. The start of science operation is expected in 2004. There are 4000 optical fibers on the telescope focal surface that will feed 16 low resolution spectrographs (LRS) and one or more medium resolution spectrograph and one high resolution spectrograph. Here we present a description of the LRS specification and its optical design. LRS is a multi object fiber spectrograph that is optimized for galaxy red shift surveys. The output bema with f-ratio of 4 from fiber are collimated by a spherical mirror and then are split to red and blue band by a dichroic filter. We use reflective grating as dispersion elements. Spectra are focused onto 2048 by 2048 CCD using fast Schmidt camera with f-ratio of 1. Spectral coverage per exposure is from 370nm to 900nm. The beam size is 200mm resulting resolution 1000 with 3.3 arcsecond fiber slit. The slit with 130mm length picks up 250 fibers, so we need 16 low-resolution spectrograph to observe spectra of 4000 celestial objects in single exposure.

The HROS is a Cassegrain focus instrument for use on the Gemini South telescope at Cero Pachon, Chile. It is of novel design, using exceptionally large optical components, and subject to the normal high flexural and stability requirements of optical wavelength instrumentation. To meet these requirements while subjecting HROS to the infinite number of gravity vectors found at the Cassegrain focus has resulted in a very difficult design and analysis of the support structure. This paper describes the mechanical design approach to meting these requirements and presents the flexural performance predictions for the structure as given by Finite Element Analysis.

HROS will be the key instrument for high resolution spectroscopy for UV to near-IR wavelengths at eh Gemini South telescope. The instrument is unique in providing a resolving power of R equals 50,000 at the Cassegrain focus of an 8-meter telescope. Taking advantage of this location, the spectrograph is optimized for high throughput, particularly for the UV region, and high efficiency. Here we present the final opto-mechanical design of the spectrograph, together with its predicted performance. In particular, we show how our design delivers an overall peak throughput of almost 30 percent and coverage of wavelengths between 325 and 885 nm in a single CCD exposure. We also discus the development of the design form the science requirements and some of the mechanical issues that drove it to this solution. Finally we report on the current status of optics procurement and testing.

We present a preliminary design study for an adaptive optics visual echelle spectrograph and imager/coronograph for use as parallel instrument of the Nasmyth Adaptive Optics System (NAOS) on unit UT3 of the VLT. The spectrograph is intended for intermediate resolution spectroscopy of faint sources. It could be used for observations of late-type dwarfs in distant Galactic clusters and in galaxies of the local group as well as for spectroscopy of extra galactic objects like quasars and Lyman break galaxies down to a limiting magnitude of V equals 22.5. The implementation of an imaging gand coronograph mode increases the versatility of the instrument and its scientific objectives. The instrument takes advantage of Adaptive Optics at visible wavelengths both for imaging and spectroscopy. With NAOS at the VLT, the light concentration in these bands will be above approximately 60 percent of the flux in a 0.3 arcsec aperture for typical Paranal conditions. Simulations show that a gain of more than one magnitude with respect to compatible non-adaptive optical spectrography will be possible for sky- and/or detector limited observations. In addition, the smaller diffraction limit in the optical than in the IR will allow a significant gain in imaging and coronography as well. Finally, the instrument will allow gathering unprecedented experience on the performances of AO at visible wavelengths, which will be fundamental for further development of AO systems, in particular for very large telescopes.

The FORS instruments are focal reducers and spectrographs which are built in two copies for the unit telescopes UT1 and UT2 of the ESO/VLT by a consortium of University Observatories. An overview of the instrument capabilities is given in a separate paper at this conference.

Motivated by a strong concern to keep maintenance work as low as possible the direction of the CFHT had for some times contemplated the possibility to replace the original mirror train f/20 focus feeding their Gecko High Resolution Coude Spectrograph by a more convenient fiber link coupled to the f/8 Cassegrain focus. A decision supporting that idea was ultimately taken two years ago and our group at the OPM was contacted to build such a system according to precise specifications. This telescope facility, baptized CAFÉ for Cassegrain Fiber Environment, has now arrived to near completion and we are able to present here its main characteristics and the technical solutions that were adopted to meet the CFHT requirements and to provide the system with the best performances in terms of robustness and efficiency.

We are proposing a new spectrograph (ATLAS) which would revolutionize intermediate-dispersion observations at the AAT. Based on the new technology of volume phase holographic gratings, and using transmission optics, ATLAS offers high throughput and a wide field. It will be ideally situated to extensive surveys of faint objects. It has been designed with a collimated beam diameter of 150 mm, giving resolution (lambda) /(delta) (lambda) up to nearly 10,000 with a 1.5 arcsecond slit and good efficiency. It will be a dual-beam instrument, to maximize observing speed and allow optimized optical coatings to be used. The project is working towards its concept design review which will occur during 2000.

The fiber link between adaptive optics and oasis will provide at the Canada-France-Hawaii Telescope a unique scientific capability to obtain 2D visible and near-IR spectra of objects in the I, J, H bands with a 200 to 3000 spectral resolution and with a 0.15 arcsec and 0.4 spatial resolution. The specific is to use microlens arrays and fibers to link the Adaptive Optics Bonnette with the near-IR spectrograph OSIS.

This paper describes a fiber fed bench mounted echelle spectrograph in white pupil arrangement for the 1.3m telescope on Mt. Skinakas. A telescope adapter with focal reducer, Zeeman analyzer and on-fiber guider connects the telescope over a set of fibers lamps is fiber connected with the telescope adapter as well. The echelle spectrograph with a resolution up to 30.000 will be used for the determination of radial velocities and the longitudinal magnetic fields of early type stars.

The low resolution spectrograph (LRS) is the first facility instrument on the 9.2m Hobby-Eberly Telescope (HET). The LRS has three operational modes: imaging, long-slit spectroscopy and multi-object spectroscopy (MOS). We present the design and early operations performance of the LRS MOS unit, which provides 13 slitless, each 1.3 arcsec by 15 arcsec, on 19.6 arcsec centers, within the 4 arcmin field of view of the HET. This type of remotely configurable unit was chosen over the more conventional slit masks due to the queue scheduling of the HET, and the instrument's remote location at the prime focus of the telescope. A restricted envelope around the HET focus at the LRS port forced a very compact design. The MOS unit has miniature mechanisms base don custom cross- roller stages and 0.25 mm pitch lead-screws. Geared stepper motors with 10 mm diameters drive the 13 axes at 0.8 micron per step. The precision of the mechanism is far greater than required by the HET plate scale of 205 microns per arcsec, but result in a robust unit. The slitlets were fabricated at the University of Texas by shadow-masking the slit area with a wire and vacuum depositing aluminum onto the silica substrates. Both sides are then coated with MgF₂ which serves as an antireflection coating and a protective layer. Web-based software is available for optimizing the orientation of the MOS unit and the placement of slitlets on objects in the field. These setup scan be down loaded to the unit for configuration outside of the beam while the HET is slewing to its next target in the queue, or while the LRS is used in imaging mode for setup on faint objects. The preliminary results presented here are from one commissioning run with the MOS, where the unit appears to be meeting performance specifications.

We have proposed a new Nasmyth instrument for the William Herschel Telescope which exploits the potential of wide field-of-view correction of atmospheric turbulence to produce a versatile, high spatial resolution, high efficiency, multi-object spectrograph and imager optimized for the 0.7-1.6 micron region. Using a low-altitude Rayleigh beacon guide star to correct the boundary layer turbulence which dominates the atmospheric seeing at La Palma on more than 25 percent of nights, MOSAIC combines the angular resolution gains of adaptive optics with the observing efficiency gains of multiple-object spectroscopy. Additional operating modes could include a narrow-band tunable filter and a fiber feed to a bench-mou8nted high resolution echelle spectrography. The instruments would provide a unique capability on 4-meter telescopes, opening up a wide variety of new scientific capabilities ranging from spectroscopic studies of crowded star fields to resolved studies of the kinematics of distant galaxies.

The Optical System for Imaging and low Resolution Integrated Spectroscopy (OSIRIS) is being designed as a Day-One optical instrument for the 10.4 mts Gran Telescopio CANARIAS (GTC). It will be the first instrument, on such a large telescope, belonging to a new class of tunable spectrographs, implementing last advances in Volume Phase Holographic Gratings and tunable imaging combined with charge shuffling capabilities, covering the optical wavelength range. OSIRIS< to be first mounted dat one of GTC's Nasmyth platforms, is designed to be compact enough to fit at the Cassegrain focus as well. The optical design is devised around the classical concept of collimator plus camera. The collimator is an off axis ellipsoidal mirror, while the f/2.475 camera consists of several groups of all spherical surfaces lenses, forming a unit together with the detector rand cryocooler. A folder mirror prevents interference with the GTC acquisition and guiding subsystem. Several combinations of color and interference filters. TFs and VPHs are available in the collimated beam, near the pupil, to provide the wide versatility of required observing modes and resolutions. Short descriptions of the OSIRIS geometry, specifications, design strategy and the optical design are presented.

We present results of laboratory test of the high resolution spectrograph, that will be soon in operation at TNG telescope, La Palma. These first result shows that the instruments performs according to specifications, providing the expected very high resolution; and that can be operated remotely according to the TNG standards.

The VIRMOS consortium of French and Italian institutes is building the Visible Multi-Object Spectrograph (VIMOS) and the NIRMOS for the European Southern Observatory Very Large Telescope. Inside the VIRMOS consortium the Technology Working Group of the Osservatorio Astronomico di Capodimonte is in charge of the design, realization and integration of mechanics, opto-mechanical interfaces, control electronics and low level control software. This paper is an overview on the VIMOS technical project managed by the TWG.

In this paper we discuss some of the recent developments with optical fibers at the Anglo-Australian Observatory. Firstly we will describe the upgrade to the SPIRAL integral field spectrograph for the Anglo-Australian Telescope. SPIRAL-B uses a crossed cylindrical microlens array to feed 512 optical fibers at F/5.5 providing a field of view of 22 by 11 arcseconds with 0.7 arcsecond spatial sampling. The performance of the fiber bundle, microlens array, and construction techniques will be described. We will also discus the development of prototype optical fiber switchyard as part of the AUSTRALIS concept study. The switchyard provides an 'optical bread' in the fiber, between the telescope and spectrograph, which allows coupling between fibers of different diameters and focal rations. A dichroic can also be incorporated into the switchyard to allow both optical and IR spectrographs to be fed simultaneously. Switchyards therefore provide much greater observing flexibility by increasing the number of possible instrument configurations. We will briefly discuss the merits of fiber switchyards and present the results of FRD and transmission test performed in the laboratory.

PMAS has been designed and is currently being integrated as a traveling instrument of the Astrophysical Institute Potsdam. It is a UV-visual integral field spectrograph, with optimized efficiency and stability for use as a 3D spectrophotometer. PMAS is prototyped for first light at the Calar Alto 3.5m telescope with an option to go to other telescopes. We present the final design layout, details of the mechanics, optics, detector systems, and instrument control. We report on the current status of the integration.

We present SPIFFI, the integral field spectrometer for the VLT. This instrument allows simultaneous observation of IR spectra in more than 1000 image points of a 2D field. With its set of four gratings and a pixel scale that can be varied by a factor of ten, SPIFFI provides high flexibility, and at the same time offers the unique possibility of diffraction limited imaging spectroscopy at an 8m-class telescope, when fed by the adaptive optics system MACAO. We outline the scientific drivers for building such an instrument, the concept of image slicing, the optical design, and the implementation of SPIFFI.

Photon-counting silicon avalanche photo-diodes (APDs) offer very high quantum efficiency, and might eventually replace photocathode detectors in high-speed photometry of astronomical objects. Laboratory studies have been performed on both passively and actively quenched APDs. Peculiarities of APDs include that the dark signal may exhibit bistability, with the count rate jumping between discrete levels. Following any photon detection, the detector itself emits some light, which might be confusing under certain conditions. Deadtimes and after pulsing properties appear favorable, but the small physical size of APDs causes challenges in optically matching them to the entrance pupils of large telescopes.

The photon address digital detector system (PADDS) in its current implementation represents a cost effective and flexible solution for photon imaging. The system is built of an image intensifiers, a position sensitive photomultiplier tube with crossed wire anodes and a digital signal processor (DSP). TO avoid the complexities involved in the development of special devices. All components used are available from stock so as to achieve reliable specifications and low cost. The evaluation of the photon events by a DSP shifts the problem of detection from hardware to software and enables an exchange of the image intensifier to match the wavelength of interest. Design considerations and the status of PADDS are presented, results of an observation of the crab pulsar are shown and future developments are discussed.

For the photon address digital detector system (PADDS), the determination of position and time of photon events depend on the algorithm used for detection. The introduction of a digital signal processor shifts the problem of evaluation from hardware to software. Different algorithms can be tested in one setup. For a point source, the algorithms can be compared by the statistical properties of the resulting distributions. The data flow in PADDS is presented and different algorithms are discussed.

We report on the design and testing of a new readout scheme for Superconducting Tunnel Junction (STJ) arrays. By grouping the electrodes in rows and columns, this method drastically reduces the number of connections and electronic circuits required for reading out a large format array of pixelated detectors. It is a generic scheme in that it could be applied to different kinds of detector arrays. Using charge sensitive amplifiers with junction field-effect transistors we verify that the energy resolution degrades primarily due to capacitance increase at the amplifier's input node. However, since each detector is read-out by two independent circuits, these two outputs can be combined to increase the signal-to-noise level. The measurements reported here were carried out on an array of 6 by 6 junctions. All junctions were biased but only 2 rows and 2 columns read-out. We compare the result to measurement carried out on a similar 6 by 6 array fabricated from the same trilayer but with individual pixel read-out. The measurements show that stable biasing of STJs is possible with the new configuration and that the measured optical spectral line resolutions are consistent with our theoretical predictions.

A family of controllers has bene developed that is powerful and flexible enough to operate a wide range of CCD and IR focal plane arrays in a variety of ground-based applications. These include fast readout of small CCD and IR arrays for adaptive optics applications, slow readout of large CCD and IR mosaics, and single CCD and IR array operation at low background/low noise regimes as well as high background/high speed regimes. The CCD and IR controllers have a common digital core based on user- programmable digital signal processors that are used to generate the array clocking and signal processing signals customized for each application. A fiber optic link passes image data and commands to VME or PCI interface boards resident in a host computer to the controller. CCD signal processing is done with a dual slope integrator operating at speeds of up to one Megapixel per second per channel. Signal processing of IR arrays is done either with a dual channel video processor or a four channel video processor that has built-in image memory and a coadder to 32-bit precision for operating high background arrays. Recent developments underway include the implementation of a fast fiber optic data link operating at a speed of 12.5 Megapixels per second for fast image transfer from the controller to the host computer, and supporting image acquisition software and device drivers for the PCI interface board for the Sun Solaris, Linux and Windows 2000 operating systems.

6dF is a fully-automated front-end for the multi-object fiber-coupled spectroscopy system of the UK Schmidt Telescope (UKST). It is a magnetic pick-place system with an positioning robot, and it will replace the manually- configured FLAIR front-end that has been operated on the telescope in its present form since 1992. The one-hour reconfiguration time of 6dF makes a range of projects possible that could not be contemplated with FLAIR. Most notable of these is the 6dF Galaxy Survey, a two-part survey of redshifts and peculiar velocities that will become the main task of the Schmidt-Telescope once 6dF is commissioned late in 2000. This will eventually lead to a determination of the large-scale distribution of mass density in the local Universe, which will be a significant achievement for a telescope in the 1-m class. The instrument will be capable of carrying out other survey projects, and 6dF spectroscopy will be the UKSTs main science product for at least the next five years. A notable aspect of 6dF has been the very rapid progress made in its construction by the Anglo-Australian Observatory's Instrumentation Division.

FLAMES is a fiber facility to be installed on the A platform of the VLT Kueyen telescope, which can feed up to three spectrographs with fibers positioned over a corrected 25 arcminutes field of view. The initial configuration will include connections to the GIRAFFE and to the red arm of the UVES spectrographs, the latter, located on the Nasmyth B platform of the same telescope, is already in operation as a long slit stand alone instrument. The 8 fibers to UVES will give R approximately 45000 and a large spectral coverage, while GIRAFFE will be fed by 132 single fibers, or by 15 deployable integral field units or by one central large integral unit. GIRAFFE will be equipped with two gratings, giving R equals 5000-9000 and R equals 15000-25000 respectively. It will be possible to obtain GIRAFFE and UVES observations simultaneously. Special attention is paid to optimizing night operations and to providing appropriate data reduction. The instrument is rather complex and it is now in the construction phase; in addition to ESO, its realization has required the collaboration of several institutes grouped in 4 consortia.

This paper presents the design, construction and performance parameters for the optical detector systems for UVES, the echelle spectrograph for the UT2 Kueyen Telescope at the ESO Paranal. A general overview at system level with a description of the individual components is also given. Emphasis is given on the CCD detectors and their performance. The two rams are equipped with large science CCD detectors, one single chip in the blue arm and a mosaic of two in the red. The blue CCD is a 2K by 4K, 15 micrometers pixel size thinned EEV CCD-44. The mosaic in the red arm is made of an EEV chip of the same type and an MIT/LL CCID-20 chip, which features a higher NIR QE and reduce fringing for the redder part of the spectral range. The read noise archived with the CCDs at the telescope is less than 2 electrons for the EEV CCDs and less than 3 electrons for the MIT/LL CCD at a readout speed of 50 kpixel/sec/port. The system s offer a variety of readout modes, binning options and readout speeds up to 625 kilopixel per second per port with linearity variations better than 1 percent peak to peak at a dark current level of around 0.5 electrons/pixel/hour.

The 40 CCDs produced at Marconi Applied Technologies are dispatched at CEA to be tested and characterized before being inserted into the MegaCam camera mosaic. We describe here briefly our CCD test bench, the measurements we perform with it and the results obtained so far. A model has also been developed to interpret the quantum efficiency results.

Fully depleted silicon pn-CCDs with an active thickness of 300 micrometers exhibit a quantum efficiency of 90 percent at a wavelength of 1 micrometers in the near IR. The multi-parallel readout architecture allows for a frame time shorter than 2 ms for a device having a format of 256 by 256 pixel. It can be operated in a full frame mode and in a frame store mode. The pixel size is 50 micrometers by 50 micrometers . The active area is then 12.8 by 12.8 mm². Cooled down to -90 degrees C the electronic noise floor is below 5 electrons at 50 Megapixel per second. Quantum efficiency measurements will be shown as well as the physical models of the radiation entrance window. A camera system with comparable specifications - except for the pixel size - was already fabricated for ESA's XMM-NEWTON satellite mission, which was launched in early December 1999. The active size of the detector is 60 by 60 mm² with a readout time of 4 ms. Future work includes the extension of the active area to 1000 by 1000 pixel, monolithically fabricated on a high resistivity 6 inch silicon wafer. The main driver for this development is ESA's planned XEUS mission, to be launched at the end of the next decade.

A synergy of digital imaging technologies is taking place that is expanding CCD applications and markets in the high speed arena. Discussions in this paper are directed toward requirements for a new class of High Speed Scientific CCDs. This paper will discuss the theoretical limits in readout rate for maintaining high performance in the areas of charge transfer efficiency and dynamic range. In particular, a high sped problem called 'substrate bounce' is discussed which represent an important speed limitation for the CCD, especially for backside illuminated sensors. Theoretical results are compared to experimental data taken from developmental HSS CCDs recently fabricated.

In this paper we present the new optical camera ROSI mounted at the 60/90/180 Schmidt telescope of the Campo Imperatore Station. We have developed a new LN₂ compact cryostat designed to be mounted directly at the internal focus of the telescope and optimized to obtain a very long duration of the cryogenic liquid. The instrument is based on a 2K by 2K thinned EEV cooled down to 180K and despite of the reduced capacity of the vessel the overall holding time of LN₂ is greater than 10 hours, providing a long working cycle. The CCD is controlled by a modified version of the Astrocam DUO provided by LSR that offers both a high readout speed and a low noise. ROSI has been equipped with the same high transmission filter set use din SUSI2 provided by CETEV. The computer design of the entire instrument allows a negligible obscure of the light path, comparable to the traditional one of the Schmidt telescopes equipped with photographic plates.

The Subaru telescope has an excellent performance of wide field of view at the prime focus. A big area of 30 feet times 24 feet is observable at a time with the prime focus camera. Making the best use of the wide view, we are constructing narrowband (NB) filter system consisting of 20 bands. This system covers the wavelengths between 4,000 angstrom and 10,000 angstrom. The band width (BW) varies form 200 angstrom to 400 angstrom depending on the center wavelength (CW). The resolving power of the system is 23. Each filter has a big dimension of 205mm times 170mm and excellent uniformities on CW, BW and peak transmittance. Employing this filter system, spectroscopy for all objects recorded in fields of view is possible at the wavelength resolution of R23. The limiting magnitude would reach 27AB in reasonable observation time even at long wavelength bands. Such deep NB imaging spectroscopic survey should provide huge catalogue on cosmological objects. Especially, photometric redshift analyses with higher spectral resolution of R23 than ordinary broadband system of R approximately equals 4, will revolutionarily develop studies on formation and evolution of galaxies together with search for large scale structures at high redshift, based on enormous statistics, for example, 10⁴ or more galaxies at high redshift of z > 3. Also, a lot of objects having strong emission lines as QSO/AGNs and Ly(alpha) or more galaxies will be discovered, because NB filter is strong in detection of emission line. The use of NB filter is strong in detection of emission line. The use of NB filter system in survey observations is surely quite conservative in concept and time consuming in general. However, combining this method with the wide field of view provided in the largest class telescope, new window to the universe is going to open.

A conceptual design study of a high-speed spectro-photo- polarimeter for the Subaru Telescope is presented. Use of Superconducting Tunneling Junction detectors was compared with the use of Hybrid Photodiode or Photomos arrays with dispersive optics. Expected performances using at the Subaru Telescope were evaluated. This instrument will be extremely useful for a large variety of astronomical studies, especially for the field of mass accretion onto compact objects: white dwarfs, neutron stars and black holes, and low amplitude photospheric pulsation studies of stars.

The recent interest in detecting asteroids and Reentrant Space Debris has developed a need for large field of view, high-resolution focal pane array cameras to provide for mapping and tracking of these object. Ideally, a number of these cameras would be used around the world to provide a complete sky map. The Japan Space Forum is currently constructing one such facility in Japan. This paper describes the construction and features of two cameras to be used at the Japanese facility. One camera will be used in conjunction with a half-meter telescope and the second camera will be used with a one meter telescope. Features of the camera included radiative cooling of the focal pane array to minimize stress on the detector assembly, a specially designed focal pane array mount to maintain flatness, a 24 hour hold time liquid nitrogen dewar, and high speed fiber optic readout. The cameras feature arrays of up to ten SITe ST002 2048 by 4096 backthinned CCDs for high performance and wide field of view.

MegaCam is the new wide-field imaging camera currently being built for the new prime focus of the 3.6m Canada-France- Hawaii Telescope. Among all the challenges imposed by the ambitious specifications of MegaCam, there is the CCD Controller. We chose to realize a new highly integrated CCD Controller and to implement some other original solutions. This paper presents the solutions we retained.

The large Binocular Telescope is currently in the pre- erection phase. The instrument has been already funded and its first-light is expected shortly after that of the LBT. Given the peculiarity of the telescope optics we designed tow prime focus cameras with two five-lens refractive correctors, optimized in the blue-side and red-side of the visible spectrum respectively. This independent coating. Detectors also reflect this choice, being optimized separately. We present the most relevant features of the instrument, the optical design as well as the structural and mechanical layout. Each of the two Prime Focus cameras gather light form a very fast, F/1.14 parabolic primary mirror. The field is corrected over roughly half a degree in size, allowing optical performances in terms of 80 percent of Encircled Energy in better than approximately 0.3 inch. Focal length is slightly increased in order to provide a better sampling using 13.5 micrometers pixel size chips. The CCD array is made up with 4 EEV 42-90 chips, per channel, to obtain an equivalent 6000 by 6000 pixels optimizing the AR coating to the U,B,V and V,R,I,Z bands respectively. The array will be read out in 10 seconds using a 1Meegapixel/second controller with four video channels. The cryostat will use a state of the art dewar to reach an holding time of several days using a limited amount of liquid nitrogen. The whole mechanical design has bene modeled using Finite Elements analysis in order to check for mechanical flexures of the mount tube and of the optical components by themselves. A brief overview of the informative facilities to be provided with the instrument and of a few science case studies that can be attacked by this instrument are also given.

The goal of much recent engineering improvements at the 3.5m WIYN telescope has been to improve imaging performance that utilizes the good intrinsic seeing at Kitt Peak. This direction complements the efforts of high order adaptive optics by maximizing the usable field. The new 'mini-mosaic' camera, which is a mosaic of 2 4K by 2K SITE CCDs is in the final stages of commissioning. With its 0.14 arc-sec per pixel scale at the Nasmyth f/6.3 focus, it is capable of adequately sampling the best delivered images from the telescope, while maintaining a relatively large field of view. We present some early performance results from this new instruments, and demonstrate the excellent image quality over the entire 9.6-minute field.

The characteristics of gallium arsenide junction field- effect transistors (GaAs JFETs) and the performance of cryogenic readout circuits using GaAs JFETs with various gate sizes ranging form W/L equals 5micrometers /0.5micrometers to 200micrometers /200micrometers to systematically measure their static characteristics and low-frequency noise spectra. We found that the low-frequency noise voltage depends on the device size in the saturation region of GaAs JFETs at 4.2 K, and the power density of the noise voltage is inversely proportional to the gate are. These findings allowed us to determine the Hooge parameter of the GaAs JFET at 4.2 K to be 4 by 10^-5, assuming that the carrier mobility is 1.5 by 10³ cm²/Vs. On the other hand, we did not find the obvious correlation between the low-frequency noise and gate size in the ohmic region of GaAs JFETs. Based on these measurements for GaAs JFETs, we fabricated and tested a dual GaAs JFET, a source-follower-per-detector (SFD) circuit, and a 20 by 3 channel SFD circuit array. The Common-Mode-Rejection-Ratio (CMRR) of the dual GaAs JFET with W/L equals 50micrometers /20micrometers at 4.2 K was determined to be 40-60 dB under small power dissipation. The performance of SFD circuits and 20 by 3 channel SFD arrays for 2D far-IR Ge:Ga detector readouts are currently being evaluated.

FEROS is a new fiber-fed bench-mounted prism-cross dispersed echelle spectrograph which has been recently commissioned at the ESO 1.52-m telescope at La Silla. The opto-mechanical concept and performance predictions have been presented by Kaufer and Pasquini. In this contribution we present the test results as obtained during two commissioning runs in October and December 1998. Special emphasis is given to the measured performance sin efficiency, spectral resolution, straylight contamination, and spectral stability. The definite highlight of the FEROS instrument performance is the high peak detection quantum efficiency of 17 percent at 550nm. These measured numbers include the 20mirror telescope, the fiber link, the instrument, and the detector while the whole wavelength range is covered by a single exposure on a thinned EEV 2k by 4k 15 micron pixel CCD and a constant resolving power of R equals 48.000. In addition the FEROS instrument proved its high spectral stability by radial-velocity observations as carried out on the known radial-velocity standard star (tau) Ceti over a time base of 2 months. By recording a calibration-lamp spectrum in parallel with the object spectrum and by the use of a simple cross-correlation technique, a rms of 21 m/s has been obtained for a data set of 130 individual measurements. FEROS has ben made available to the ESO community in January 1999.

A brief overview is given of the data-reduction software (DRS) being developed at Geneva and Paris Observatories for the fiber-fed multi-object GIRAFFE spectrograph - part of the VLT FLAMES facility. The specific aspects of each of three modes is presented and discussed. The localization and the extraction are described in more details, the original features are outlined and the critical issue addressed. We discuss the problem of the PSF variation across the surface of the detector and the impact on the sky subtraction. The strategy of the real-time data quality assessment using the simultaneous calibration exposure is described. Some aspect of the DRS implementation and the VLT environment are discussed. The dirty prototype of the DRS under Matlab including the crude instrument simulator is discussed and some experiments measuring the expected accuracy of radial- velocity are shown.

Our team is designing and realizing the fiber links from which two spectrographs will operate at the second unit of the Very Large Telescope. GIRAFFE is an intermediate resolution spectrograph which has access to the entire field of the Nasmyth focus and is equipped with three fiber links producing alternately 132 spectra at the same time, 15 tri- dimensional spectra or 300 spectra for a single object. The last fiber link is intended to provide simultaneously with GIRAFFE, the observation of 8 objects at a higher resolution with UVES. All these observation modes will be available at VLT by the end of 2001. The specific development of the fiber links includes the systematic use of simultaneous calibration. This paper sums up the design of each mode and describes the specific developments required to optimize the performances of the fiber system. A full description of GIRAFFE, of its fiber link and of the related scientific programs is available at http://giraobs.obspm.fr.

The Potsdam Multi-Aperture Spectrophotometer (PMAS) is a flexible UV-visual integral field spectrograph designed for operation at different telescopes. It is based on a dedicated fiber spectrograph with a novel, fully dioptic collimator-camera system. The optical system was specifically optimized in terms of efficiency and stability for operation with a fiber input. The final optical design is described with remarks concerning the manufacture and acceptance test results.

The Echelle Spectrograph and Imager (ESI) is a multipurpose instrument which has been delivered by the Instrument Development Laboratory of Lick Observatory for use at the Cassegrain focus of the Keck II telescope. ESI saw first light on August 29, 1999. The optical performance of the instrument has been measured using artificial calibration sources and starlight. Measurements of the average image FWHM in echelle mode are 22 microns, 16 to 18 microns in broad band imaging mode, and comparable in the low- dispersion prismatic mode. Images on the sky, under best seeing conditions show FWHM sizes of 34 microns. Maximum efficiencies are measured to be 30 percent for echelle and anticipated to be greater than 38 percent for low dispersion prismatic mode including atmospheric, telescope and detector losses. In this paper we describe the instrument and its specifications. We discuss the testing that led to the above conclusions.