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--- pld:start [2015/02/10 22:31] – james
+++ pld:start [2015/02/11 12:47] – james
@@ Line 61: / Line 61: @@
 ==== Mirrors ====
-The 3 mirrors used in the optical tower are from OptoSigma (part no. 034-0185 and ).  These mirrors are made of a borosilicate glass (BK7) and are designed specifically for KrF laser use at 45 degrees incidence. When configured in this way, the reflectance should be > 99%. The mirrors on the lowest two tiers of the optics tower are arranged at this angle of incidence.  The mirror on the highest tier of the optics tower is setup such that the angle of incidence is 30 degrees.
+The 3 mirrors used in the optical tower are from OptoSigma (part no. [[http://www.optosigma.com/products/optical-components/mirrors/laser-line-mirrors/034-0185|034-0185]] and ).  These mirrors are made of a borosilicate glass (BK7) and are designed specifically for KrF laser use at 45 degrees incidence. When configured in this way, the reflectance should be > 99%. The mirrors on the lowest two tiers of the optics tower are arranged at this angle of incidence.  The mirror on the highest tier of the optics tower is setup such that the angle of incidence is 30 degrees.
 {{:pld:bk7.jpg|thumb}}
 \\
 ==== Lenses ====
 The two focusing lenses (one for each chamber) used are of the plano-convex type, and are made of UV grade fused silica.  The lenses used have no coatings, and have different focal lengths.  The lens used with the Thermionics chamber is OptoSigma part no. {{:pld:fused_silica_plano_convex_lenses.pdf|014-1315}}.
 ==== Windows ====
-There are many windows on the thermionics chamber.  However, there are two UV grade laser windows.  Each of these is mounted in a ConFlat flange.  Each of the laser windows is made of fused silica, and measuring with the Coherent power meter, have a loss of approximately 10% at 248nm.
+There are many windows on the thermionics chamber.  However, there are two UV grade laser windows.  Each of these is mounted in a ConFlat flange.  Each of the laser windows is made of [[http://marketplace.idexop.com/store/SupportDocuments/MaterialProperties.pdf|fused silica]], and measuring with the Coherent power meter, have a loss of approximately 10% at 248nm.
 ===== Procedure =====
@@ Line 77: / Line 78: @@
 {{:pld:gas_change_20120606.pdf|Laser Gas Change}}
+__**Viewing window cleaning procedures**__
+Use the paste from lambda physik called Vienna chalk, it is actually a white powder. You need to make a slurry, and a few drops of water go a long way.
+When you think that the slurry is too thick, it is just right.  If it is too watery, the abrasive in the slurry will be ineffective at cleaning.
+Change lens tissues often. As the voids in the paper clog, the cleaning efficiency goes way down.
+After you have cleaned a window, there will be water droplets in small voids that are difficult to dry. This will kill the chamber pressure for quite a long time. You can reduce this by rinsing the window with isopropanol, and then blow drying with N2 gas.  Do this 3-4 times, and be thorough.  Ideally, you would bake the window at 120 C for an hour after this treatment, but most windows will not fit in the furnace we have available.
 FIXME
-Chamber cleaning procedures, viewing window cleaning procedures
+Chamber cleaning procedures
 ===== Routine Maintenance =====

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