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April 4, 2017: Posted mechanical part shop drawings and STEP files

Here

April 4, 2017: PMT Shutters Modification

See Partslist page for information about adding PMT Shutters for experiments where imaging is needed quickly after 1p photostimulation, and where it is impossible to block bright light from reaching the PMTs with chromatic filters.

February 16, 2017: Additional mounting hardware for Motorized Mirror Cover assembly

The magnets which were included with the original design of the motorized mirror cover assembly have insufficient strength to hold the assembly together.  Additional latches were added to the design to perform this function.  An updated parts list and DWF model are posted (in both cases, the main parts list and model have not been modified–look for the updated file for this specific assembly).  The threaded holes necessary to use these should already be present in the custom cover pieces that were received.  Note that the long #10-24 screw/washers/nut shown replaces a standard #10-24 screw which was used to fix the Big detection lens holder to the main optical table.  The washers/nut allow the screw to be fixed in position and still support the Big detection lens holder, while also extending out to be used to support the motorized mirror cover assembly. The custom 3d printed latch may have already been sent out to each lab that participated in the 2p-RAM workshop (if not, then please email or comment).  For the side latches, it may work easier if they are inverted from what is shown, with the small, button strikes on the top cover piece.  In the way shown, when the bottom cover is removed, the latches swing down into the assembly, potentially touching the dichoic/mirror, and generally getting in the way.


February 16, 2017: Entrance Beam Expander position

We found that if the Entrance Beam Expander were positioned as shown in the models then part of the beam could clip/reflect off of the Resonant mirror chamber.  We solved this by moving the beam expander completely downstream of the resonant mirror chamber, as shown below.  Also, we changed the magnification of this expander to 3x (using Thorlabs f = -50 mm and f = 150 mm -B achromat lenses), after more carefully adjusting the colimation of the beam out of the 2x expander that comes before the prism pair compressor (which made the beam larger after propagation to the microscope).  In general, it is probably optimal to make the beam as large as possible going into the remote focus objective, such that the maximum power that can be transmitted to the sample (100% power in ScanImage) is as large as you think you'd ever want to use.  This was around 200 mW for us (See Podgorski, Ranganathan, J. Neurophys 2016.)  For reference, I think that we could get at least 50% more power with our Chameleon at 970 nm if we didn't overfill the remote focus objective as much.

October 18, 2016: Accessory optics system: Coverglass alignment system alignment issue

It's possible that the spot that the coverglass alignment system should project onto the camera for this system does not hit the camera, due to small misalignments of several optics, even when the coverglass is perfectly aligned with the imaging objective.  There are few degrees of freedom to fix this, as the assembly is currently modeled.  We fixed this by separating the LED and pinhole from the accessory optical systems main body, and attaching it to the main microscope vertical breadboard, allowing it to move in x and y relative to the rest of the system.  See picture below. 


October 13, 2016: Accessory optics system: 1p photostimulation galvo issue

The design of the standard electrical connector for the 6210H galvo changed at some point in the past, and the accessory optical system design only works with the old connectors, while the galvos purchased for the accessory optical system (XY 6210H galvos w/ 3mm aperture mirror set) have the new connector.  As such, the y-axis galvo will NOT FIT into the 2p-RAM system (it's connector hits PupilRelay3).  The easiest way to fix this problem is to purchase a replacement 6210H galvo with the old style connector, which is still available.  Gary Tillman <Gary.Tillman@cambridgetechnology.com> created system part # 6SD11390 ($677) for this, and it should contain the proper galvo, a y-axis mirror (attached to the galvo), and the proper wire to connect the galvo to the driver.  He thought that it would not be necessary to send your driver in to be retuned to the new galvo.  (It would be best to confirm all of this with Gary when you place the order.)  There IS a 10-12 week lead time to receive the galvo, however. 

If a fix is needed in less than 10-12 weeks, then there is an alternate, 2-step solution (see photo below). 

  1. Take the y-axis 6210H galvo, remove the electrical connector that is soldered to it (cut it off, and then desolder the pins one at a time), and then remove the connector on the cable that goes with the galvo and solder each wire directly to the galvo PCB board.
  2. Modify the accessory optics system main housing: the pocket that accomodates the y-axis galvo PCB board needs to be widened and made more deep, as this PCB is itself different on the newer galvo design.  The pocket should be widened to have a 39mm diameter, and should have its depth increased by 1mm.  The hole that the galvo itself goes through need not be changed.

From left to right: The old style connector.  The new style connector.  A galvo with the new-style connector that was made to fit into the old design through soldering the wire directly, and modifying the accessory optics main body part.

 

 

October 12, 2016: Resonant mirror angle alignment issue

Issues with alignment were found when using the original resonant mirror angle alignment procedure.  A new, in situ procedure was developed, which does require modifying the resonant mirror chamber part from the original design.

September 2016 and previous

NEW- Custom condensor lens from IRD

The custom condensor lens (to be attached to the PMT) is not ideal. IRD was not able to manufacture the lens without a chamfer on the stem of the mushroom, which prevents the lens to fit entirely into the PMT opening. However, the gap between condensor lens and the PMT housing is sufficiently small so that we do not consider this a problem. You may have to press the lens into the PMT opening. 

We were offered a 25% discount on this order, due to this issue.  Please check that this discount is applied on your invoice.

 

NEW- Collection of additional optional parts
These were the parts that we bought during the construction of the 2p-RAM for the workshop. In the previous partslist these were items under 'user supplied parts' (e.g. enclosure of the laser). Use your own discretion as to what you might need.
Update Aug 29: size of two mirrors have been increased.

NEW- Essential additional items for the Thorlabs kit
There are items that did not make it into the original Thorlabs kit order.

Dowel pins update

Order better dowel pins: MSC (http://www.mscdirect.com/) part # 88231998 Dowel Pins; 

(MCMASTER-CARR 90145A567 Dowel Pins are BAD)

 
Zera issues
Three pieces need fixing.

Gary Zera from Zera Development will be reaching out to all of you regarding modifying two additional parts (three in total). 

Alternatively, you can have your shop fix the pieces.

 

J003114 - Det tube

The surface that needs to be fixed is marked with the Diameter 3.055 dimension (zone C1).  The center of this curve has to be located using the dimension 2.820 (it currently is located using the dimension 2.835).

J003119a - Secondary dichroic holder 
The surfaces that need to be fixed are marked with the R.094 dimension.

J003119A.pdf


J003103 - Primary dichroic cap 

The surface that needs to be fixed is marked with the .434” dimension (zone D3 on the drawing).  See picture.  The proper datum surfaces A and B need to be used to measure this dimension correctly.

J003103.pdf





PMT issue
PMT — it looks like some of you ordered 

H10770PA-40 SEL - GaAsP without shuttering

instead of 

H11706P-40 SEL - GaAsP with shuttering

Left, H11706P-40 SE; right, H10770PA-40. 

Obviously the size of the PMTs is different. The PMT holder was designed for H11706P-40 SEL.
H10770PA-40 SEL has a smaller crossection and no mounting holes.

SOLUTION: It should be relatively easy to glue this PMT to the provided PMT holder. Simply replace the WPI Kwik-Cast with some 5 min epoxy. Make light tight with some electrical tape if necessary.

 
 

 

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12 Comments

  1. We are modifying the holder to have a 4 x M2 countersunk holes to mount the PMT. Will share the files once the modifications is done and we confirm that it works. -Natalia

  2. Are you sure this statement is correct ?

    MCMASTER-CARR 90145A567 Dowel Pins are BAD

     

    I only see 97352A610 pins in the CAD. Is it possible you gave the wrong "wrong part" number?

    1. All from McMaster are bad.  Get the pins from MSC, as a replacement for 97352A610.  97352A610 were our first choice pins, and 90145A567 were the ones we tried next.  The third time was the charm for these.

      1. Dan,

        We purchased pins with the same size and tolerance as those from MSC, but from a local company. Do you think it's maybe not even worth the gamble and we should buy again from MSC?

        1. That's a tough call.  I'd say, look at the pins themselves.  Do they look quality?  (smile)  Seriously, the McMaster 90145A567 pins had the same tolerance as the MSC pins, IIRC, but you could see that the finish was worse (larger, more visible scratches), and the chamfers on the ends were less "engineered" and more "random" looking.  The MSC pins are also not the highest quality, I'd bet, so there's a good chance your local ones are better.

          1. Thanks, I'll look and make the call.

  3. Yeah, I noticed the charm. Unfortunately I have some of the old pins in there that might be harder to remove. The new ones were indeed very nice

    1. You might want to try the pin puller from McMaster.  Could save some headache.

       Dowel Puller92330A300$65.55
      Stud for Small Dia. Pin92330A41127.80
  4. Hi Dan,

    Regarding the Coverglass alignment system alignment issue, do you know what the source of the misalignment is?

    I had the feeling that the motorized dichroic slider "In" position is actually too far in. What do you think?

     

    1. Hmm...I'm not too sure.  I don't THINK that the motorized slider should be significantly off.  The "in" and "out" stops are fairly precisely set, and I looked over the design many times.  I'm hoping that an optical illusion of some type is responsible for your "feeling".  (smile)  Or maybe you are using the frame pieces wrong somehow (backwards or with the dichroic on the wrong side)?  The angle of the big dichroic could be a little off.  I think that the flip mirror is probably the least well controlled single item, and the alignment of the whole secondary optics assembly relative to the rest of the rig isn't very well controlled either.  When I had to move the camera assembly, I had to move it significantly in two dimensions, so that also argues against something simple and 1 dimensional like the slider dichroic.  Anyway, I'm pretty sure that the issue is confined to the accessory optical system, in a way that doesn't effect much, except for getting the beam for the alignment system back onto the camera!

  5. Should we have the side latches for the cover? I only have the main latch. 

     

    1. You need the side latches, but we didn't send them from Janelia.  They are available from McMaster-Carr, and their part number is on this parts list: https://openwiki.janelia.org/wiki/download/attachments/50823235/MotorizedMirrorCoverAssby_PartsList_Updated20160812.xls?version=1&modificationDate=1487265806000&api=v2 .  There are also a few other parts on this list (nuts and bolts) that you need to buy to get everything to work.