Recently, satellite broadband communication services using Ka-band are emerging all over the world, some of them with capacities in excess of 100 Gbps. However, as the radio bandwidth resources become exhausted, high-speed optical communication can be used instead to achieve ultra-broadband communications. The National Institute of Information and Communications Technology (NICT) in Japan has more than 20 years of experience in R&D of space laser communications, with important milestones like ETS-VI (Engineering Test Satellite VI), OICETS, and SOTA. We are currently developing a laser-communication terminal called “HICALI”, which goal is to achieve 10 Gbps-class space communications in the 1.5-μm band between Optical Ground Stations (OGSs) and a next generation high-throughput satellite (called ETS-IX) with a hybrid communication system using radio and optical frequencies, which will be launched into a geostationary orbit in 2021. The development of test and a breadboard model for HICALI has been conducted for several years and we are now carrying out an engineering model as well as designing the OGSs segment. In this paper, we describe concepts and current design status of the HICALI system.
Mask development process for 2x nm node devices needs stringent CD uniformity and CD linearity. To evaluate and
improve these CD qualities, we proposed to introduce electric-field-induced-development method into proximity gap suction
development system (PGSD). It is the way to develop with applying electric potential to the metallic development nozzle to
stimulate the movement of hydroxide ions. In this paper, we will report the effect of electric-field-induced-development
method on CD uniformity and CD linearity.
Development process for 3x nm node devices and beyond is becoming a great issue in mask
fabrication. The following items, such as uniformity, repeatability, loading effect and defect must be
improved. To evolve the development process, TEL, DNP Omron and Toshiba have been jointly
developed next generation equipment which is called "Second-generation PGSD (Gen.2)".
In this paper, PGSD Gen.2 concept is introduced and its performance is reported.
The performance of the Cassegrain Adaptive Optics (AO) system of the 8.2 m Subaru Telescope is reported. The system is based on a curvature wavefront sensor with 36 photon-counting avalanche photodiode modules and a bimorph wavefront correcting deformable mirror with 36 driving electrodes. This AO system has been in service since 2002 April for two open-use instruments, an infrared camera and spectrograph (IRCS) and a coronagraph imager with adaptive optics (CIAO). The Strehl ratio in the K-band is around 0.3 when a bright guide star is available under 0".4 seeing condition. High sensitivity of the wavefront sensor allows significant improvement in the image quality, even for faint guide stars down to R=18 mag. The design of the new Nasmyth Adaptive Optics system with 188 control elements under construction is described. This new system with fivefold increase in the number of control elements will provide twice higher Strehl ratio of 0.7. To increase the sky coverage for this new system, a power laser system to produce an artificail guide star in the upper atmosphere is also under construction. The AO system with laser guide capability enables the coverage up to 80% of the entire sky and offers diffraction limited observation for almost any target in the sky. An all solid-state 4W laser to generate the sodium D line emission by summing the two YAG laser frequencies is under development. The generated laser beam is tranmitted through a photonic crystal fiber to the laser launching telescope attached at the backside of the secondary mirror. Expected performance of this laser guide Nasmyth AO system is shown.
As an upgrade plan of Subaru adaptive optics facility, laser-guide-star adaptive-optics (LGSAO) project is on going. One of key components of the project is a deformable mirror (DM). The DM for LGSAO is a bimorph type of PZT with 188 control elements. The specification of design is presented together with the analysis of stroke and vibration properties by FEM.
We present the development status of the laser system for Subaru Laser Guide Star Adaptive Optics System. We are manufacturing the quasi-continuous-wave sum frequency laser as a prototype. The optical efficiency of sum frequency generation normalized by the mode-locked fundamental YAG (1064 nm) laser output power is achieved to be 14 % using the non-linear crystal, periodically poled potassium titanyl phosphate (PPKTP). Output power at sodium D2 line was about 260 mW. The optical relay fiber and the laser launching telescope are also described in this paper. For the optical relay fiber, we are testing an index guided photonic crystal fiber (PCF), whose core material is filled by fused silica, and whose clad has close-packed air holes in two dimension. The coupling efficiency was evaluated as about 80 % using 1mW He-Ne laser. We introduce the design of laser launching telescope (LLT), which is a copy of VLT laser launching telescope, and the interface to the Subaru Telescope.
The Subaru Telescope LGSAO system is a 188 elements curvature AO system currently under construction, and scheduled to have first light in March 2006 for the Natural Guide Star mode and March 2007 for the Laser Guide Star mode. A particularity of this system will be to perform curvature wavefront sensing with several extra-pupil distances, which significantly improves the closed-loop performance.
An overview of the predicted performance of the system is given for Natural Guide Star and Laser Guide Star modes.
Faint Object Camera and Spectrograph, FOCAS, is a Cassegrain versatile optical instrument of Subaru telescope. Among various observing modes of FOCAS, the multi-object spectroscopy (MOS) requires dedicated software suite which enables accurate positioning of masks which have over fifty slitlets on faint targets over 6 arcminutes diameter field-of-view (FOV). We have been developing three kinds of software: the image processing software performing combining mosaic CCD images and optics distortion correction, mask designing program (MDP) for the slit arrangement, and pointing offset calculator (POC) for the target acquisition on slits. MDP and POC provide observers a graphical user interface (GUI) for efficient and quick mask designing and target acquisition. Our test has shown that the slit positioning accuracy on targets is about 0.2 arcsec RMS over entire FOV, and is accurate enough for typical observations with 0.4 arcsec slits or wider. We briefly describe our software as well as the pointing accuracy and the required time for the MOS target acquisition with FOCAS.
The Faint Object Camera and Spectrograph, FOCAS, is a Cassegrain
optical instrument of Subaru telescope. For its versatility, FOCAS
has many optical components such as grisms, filters, and polarizers.
They are inserted in the collimated beam section of 451 mm length.
For the large pupil (90 mm in diameter) and the wide field of view
(6 arcmin in diameter) of FOCAS, rigorous efforts were made in
developing, manufacturing and assembling these components.
The resultant performance of the instrument is quite stable
and is almost as high as that expected from the design values.
In the text, overall characteristics of each optical element
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.
Faint Object Camera And Spectrograph (FOCAS) is completed and now waiting for a commissioning run on the Subaru Telescope atop Mauna Kea. We have developed a software system that includes the control of FOCAS instruments, Multiple Object Slits (MOS) design, and an analyzing package especially for evaluating performances of FOCAS. The control software system consists of several processes: a network interface process, user interface process, a central control engine process, a command dispatcher process, local control units, and a data acquisition system. These processes are mutually controlled by passing messages of commands and their status each other. The control system is also connected to Subaru Observation Software System to achieve high efficiency and reliability of observations. We have two off-line systems: a MOS design program, MDP, and an analyzing package. The MDP is a utility software to select spectroscopy targets in the field of view of FOCAS easily through its GUI and to design MOS plates efficiently. The designed MOS parameters are sent to a laser cutter to make a desirable MOS plate. A special package enables prompt performance check and evaluation of the FOCAS itself during a commissioning period. We describe the overall structure of FOCAS software with some GUI samples.