PLATE CHANGER for OIL microscopes Gabriele Sirri INFN Bologna for INFN Bologna and LNGS

MizunamiG.Sirri - INFN Bologna2 12 plate changers delivered by TecnoCut to scanning laboratories (June 2008) All system commissioned by TecnoCut (hw components only) (Sept. Oct. 2008) LNGS

MizunamiG.Sirri - INFN Bologna3 3 Plate Changers already interfaced with Scanning System : - LNGS MIC2: setup for GLUED emulsions - BO MIC5: setup for GLUED emulsions - BO MIC4: setup for NOT GLUED emulsions BOLOGNA glued/not glued details see OPERA Coll. Meeting

MizunamiG.Sirri - INFN Bologna4 alignment tool cleaning tool Loading basket fresh separa- tors Emulsion collector Microscope stage Separator collector oil main plate mover

Present status MizunamiG.Sirri - INFN Bologna5 A basic working release of the software is ready.  Macros to manage the Load/Unload/Oil Dispense jobs  Scanning and Fiducial Mark Finding macros modified to integrate Oil Dispense The Plate Changer can handle automatically the full brick. For not-glued emulsion, non-planar emulsion and safety some additional tools has been tested  A frame press to help vacuum on the glass window  compressed air nozzle to help emulsion detachment from the glass window  compressed air to help emulsion detachment from the cleaning tool surface  proximity switch to inhibit microscope movements when platechanger arm is over the glass window

EMULSION suckers MizunamiG.Sirri - INFN Bologna6 Additional tools PRESS to press down the emulsion during vacuum Nozzle to provide high pressure (8 bar) compressed air for a safe PLATE UNLOAD GLASS WINDOW AIR

Load / Unload movies MizunamiG.Sirri - INFN Bologna7 platechanger_unload_plate_ wmv platechanger_load_plate_ wmv

Test and Measure MizunamiG.Sirri - INFN Bologna8  Full brick load/unload skipping oil (no mark finding, no area scanning, …) : ok (glued/not glued)  Scanback and totalscan of some bricks (oil distribution included) driven by scanning infrastructure : not glued: plate changer ok but …. too lateral mark finding failures (focus problems outside the vacuum channel due to oil) glued: ok … In both cases: fine tuning of mark finding parameters and alignment tools and …frequent cleaning of separators, suckers, surfaces, …

Lateral Mark Absolute Position [1 brick] MizunamiG.Sirri - INFN Bologna9 No mark finding failures, uncertainties come from: Brick Assembly + X-ray Marking + Gluing + Plate Changer + Mark Finding

Lateral Mark Absolute Position vs Plate number MizunamiG.Sirri - INFN Bologna10

Conclusions MizunamiG.Sirri - INFN Bologna11 The hardware and firmware set up are complete. Basic working software available. Final setup of all plate changers before the beginning of the next run is foreseen. Mark finding improvements needed: - focusing before lateral mark search (most useful for not glued emulsions ) - new vacuum glass windows design to be compliant with 4 lateral marks (not glued emulsion) -plate number check after load

Vacuum plates Standard plate plate with holes Glued emulsion larger vacuum channel = Emulsion vacuum Mizunami13G.Sirri - INFN Bologna

15/19 Mark recognition Not possible to be done:  No extra camera with low magnification optics are available Only a small amount of the lines can be scanned  The two lines are not always long enough to print a clear crossing point Not possible to scan only one FOV per mark The approach is:  Three pieces of each line are scanned and lines are obtained by a linear fit. The coordinates of intersection point are the mark coordinates. NO Intersection point

New Lateral Mark Finding Strategy (release>=62) 1. Scan along a perpendicular path (a) 2. Get other strip samples towards the emulsion center until candidates are found (b) Nominal edge 1° candidate found here Expected Mark Position X (a) The trajectory lays between the nominal edge and the expected mark position. The path length is “Scan Transverse Tol.” parameter. (b) The number of samples is “Max Strip candidates” parameter (1st included). The interdistance between segments is “Strip Sampling Distance” parameter Y strip case 3 4. Segments are fitted to a line. Same for the other strip. Mark position: intersection point between fitted lines. 2/ Get strip samples in the opposite direction if needed (b) No candidate found here.