1 / 33

ELT Studies in Japan Masanori Iye (NAOJ)

ELT Studies in Japan Masanori Iye (NAOJ). # ReOrganization of NAOJ+4 to NINS (as of Apr. 1, 2004) 3 times larger in budget and staff, increased flexibility? # Future Planning WG for Opt/IR community => White Book (2004 summer) # No Specific Budget for ELT R&D

edythe
Télécharger la présentation

ELT Studies in Japan Masanori Iye (NAOJ)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. ELT Studies in JapanMasanori Iye (NAOJ) # ReOrganization of NAOJ+4 to NINS (as of Apr. 1, 2004) 3 times larger in budget and staff, increased flexibility? # Future Planning WG for Opt/IR community => White Book (2004 summer) # No Specific Budget for ELT R&D => request for 5 year R&D budget to JST/MEXT # Yet, some studies are under way for a 30m JELT. Reports on individual studies Caution: including yet-personal perspectives! M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  2. Baseline Specification : Japan ELT M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  3. Some new initiatives • Optical design : 3 Aspheroc mirrors (Nariai/Iye) • Coated CFRP replication segment (Mitsubishi/NAOJ) • ZPF segment(Taiheiyo Cement/NAOJ) • High precision grinding machine (Nagase Integrex) • Light weight structure (Nagoya Univ., Mitsubishi) • Direct Drive Motor (Mitsubishi) • Segment support & adjust (Kyoto Univ., Melco) • ELID grinding (RIKEN) • LGS 188 element AO (NAOJ) • AO PSF Simulations (NAOJ) • Site Study(NAOJ)… M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  4. Optics: 3 Asph. Mirror Telescope (Nariai/Iye) characteristics /aberration free /flat image plane /M4 conjugate to 16km /shorter telescope /two arms on each Nasmyth stage 4m DMs? M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  5. JELT Optics Layout M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  6. Superb image quality: diffraction size@0.6um=10mas M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  7. CAD Model: 30m telescope with 3 aspheric mirrors M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  8. Nasmyth layout M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  9. FEM analysis for JELT AZ Thrust Hydrostatic Bearing with Drive Journal EL Radial and Thrust Hydrostatic Bearing with Drive Yoke Structure AZ Track M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  10. Z Y X Characteristics of Yoke Structure Tube (assumed mass : 750 tons) Yoke (Mass : 350 tons) Natural Frequency Analysis Model M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  11. Segment Fabrication ・ New zero-expansion material for segments 1) coated CFRP : replica fabrication(Melco) => low cost, suppression of humidity deformation 2) ZPF : grinding/polishing Zero-expansion Pore-Free ceramic(Japan Ceratech/ Taiheiyo cement) ・ Direct Grinding (Nagase Integrex) no/little polishing => reduction of time/cost M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  12. Test on coated CFRP • Cyanate CFRP: CTE 30ppb /C, light weight 1.5g/cm3 • Cheaply replicated from mother mold. • Affordable surface roughness • Deformation for absolute dehydration 20ppm with time scale of 500hrs • Water tight coating to give 100 times longer time scale may give < 3ppb change in 1 hour. *Need for static correction? M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  13. Weight increase rate of dehydrated CFRP due to moisture absorption in laboratory M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  14. CFRP Tests at Subaru enclosure • Cyanate CFRP protected by Al foil was monitored for its weight variation at 10-7 mass resolution during three months at Mauna Kea. M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  15. /Deformation due to the variable moisture content in 2 months was 220ppb, 4 times larger than thermal deformation of ULE, 60ppb, for 20C change. => Reducable by optimizing plastic material and/or carbon content? M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  16. Zero-expansion Pore-Free CeramicJapan Ceratech/Taiheiyo Cement • Thermally zero-expansion material (10ppb) • Stronger than glass for damaging (~ twice) • Machinable and polishable just like glass. • Aluminum deposition can be made. • Follows temperature variation 3 times faster than glass. • Acceptable surface roughness (a few nm rms). • Light weight structuring and sagged disk feasible • New facility plan for production of larger disks. • Somewhat less expensive than glass(?) M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  17. Physical characteristics of materials M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  18. Long-term stability Zero-expansion Pore Free ceramic ZPF (Taiheiyo Cement) M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  19. Zero-expansion Pore-Free Ceramic (ZPF)10ppb(at 0C), High elasticity, Pore-free, Cementable, Long term stability, Light weight structure, Polishable • Polished at NAOJ • roughness7nm rms M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  20. 30cm ZPF honeycomb mirror *Honey comb structure 2.4 => 1.7g/cm3 (30% reduction) *Polished by NIKON to 1/12 λrms without a problem *No apparent print through of back structure M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  21. M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  22. RMS 14nm surface roughness M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  23. High Precision Grinding Machine (Nagase Integrex) # Work stage upto 4mx2m! # Friction free hydrostatic bearing => 10nm accuracy 1nm resolution # Dynamic balancing of spinning tool Yamagata Industrial Research Inst. M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  24. High Precision Nagase Grinding Machine • FMOS aspheric Schmidt plate 28x24cm, loose specification for fiber imaging • One-time grinding off • Roughness 80nm • Figure error 200nm *metrology measurement • Iterative grinding with optical interferometric measurement has just tested on 10cm ZPF. M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  25. M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  26. 1st NC grinding experiments • Three 10cm ZPF disks ground to R=30cm sphere • ZPF1 rotated, #1500, • ZPF2 rotated, #3000, a few hours work, (smaller R at the center) but surface error < 3 λover 65% of the surface • ZPF3 raster scanned, 0.5mm then 0.1mm pitch, overnight grinding => (grinding tracks visible) figure error under evaluation. Remember this is the result of first 5 days and optimizations of parameters are yet to be seeked for!!! M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  27. M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  28. 1st NC grinding w. rotation • #3000grit, PV<3λ(over 65% area) M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  29. 1st NC grinding in raster mode 1st day(June 17th) result: PRELIMINARY Apparently needs to optimize the grinding head shape, pitch, speed of raster 0.5mm 0.1mm M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  30. Light Weight Structure M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  31. Solid-State Sum Frequency Generating Sodium Laser M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  32. (Laser Diode pumped) Mode-locked Nd:YAG Lasers M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

  33. SUMMARY • Experiencing to have a major reformation of research organizations and is hoping to take this chance to promote an ELT plan. • Has some expertise around Subaru Telescope • Inviting a few new industries for R&Ds toward cost saving realization of ELTs. • Tentatively drawing a 30m ELT plan. • Applying for a 11M$ R&D budget to MEXT/JST • Is open for participating in international collaboration to construct ELTs. M.Iye/NAOJ SPIE Meeting @Glasgow, June 22, 2004

More Related