Transcript 4 mirrors
1 m2 mirror technology AIM find a suitable technology for large reflecting surface •reduce the overall cost with respect the current tecnology •Improve or maintain the actual optical quality •Avoid the use of panels for Active Mirror Controls •Develop technologies for very large reflectors M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Current technology: raw blank prduction M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Magic I technology: pre-milling Front plate Honeycomb sandwich M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Current technology: Diamond milling M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Panel assembling in Eching Adjustment legs screwed on the mirror Cabling of the mirror for internal heater 2 mirrors mounted on a panel M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Pre-alignment of a mirror in a panel A panel in the alignment tripod M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Alignment tools Artificial parallel beam source Rotating tripod for panel alignment M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Final alignment Final spot of a panel after The precise alignment of the mirrors 4 mirrors spots after the pre-alignment close to the virtual center of the MAGIC camera M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Large single mirror vs 4 small mirrors in a panel 4 mirrors: •better optics •more labor + expensive panel needed •hand made first aligment (+?) •many high tech elementsto build a panel •Diamond turning prooven technology 50 cm mirrors AMC motors Single large mirror: •Astigmatism important at large radii •Self supporting ->no panel needed •No manual alignment necessary •Big labor for the premilling •Diamond turning OK 1 m mirror M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Ongoing R&D in Padova Built 1m mirror with native spheric shape aluminum sandwich glued on a spheric mould Front plate Mirror box + honeycomb mould M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Ongoing R&D in Padova Built 1m mirror with native spheric shape aluminum sandwich glued on a spheric mould QuickTime™ and a TIFF (U ncompressed) decompressor are needed to see this picture. M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Ongoing R&D in Padova 6 Prototype produced: Light weight : <18 Kg, ready to be installed in the telescope without any support panel QuickTime™ and a TIFF (U ncompressed) decompressor are needed to see this picture. QuickTi me™ and a TIFF (Uncompressed) decompressor are needed to see this picture. M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Diamond milling of 1M mirror M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Diamond milling first round - Good reflectivity -Bad sphere ~ donuts: -Error in the alignment of Diamond tool M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Diamond milling second round Almost a perfect sphere. The rigidity of the new mirrors and the tune-up of the milling machine are now delivering very good results: The technique is becoming reliable M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Impact of 1m2 in the reflector optical quality QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Impact of 1m2 in the reflector optical quality Full simulation is needed: modification of reflector program. hybrid combination: rings with small mirrors combined with rings with large mirrors (Denis & Michele) Option of 2 radii of curvature for outer rings: -technique to be proven but promising -need 60 Keuro of investments drawbacks -> not easy task to measure and check the optical quality. -> each mirror will become “unique” in the reflector M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005 Roadmap •3 new 1 m2 prototypes are going to be mounted on MAGIC next week to replace damage mirrors & “taist” the winter •Mini workshop to define interfaces mirror->AMC->dishstructure • Test production on selected company for raw blanks • Funds&test for new diamond tooling @LT-ultra • Pre-production • Production (1+/day in pipeline) M. Mariotti,D.Bastieri, M.Doro. MAGiC Coll. Meeting Tenerife 14-16 ott 2005