40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
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Entry  Mon Jul 22 09:44:21 2019, Jon, Lab Infrastructure, Computing, Installed Amplifying VGA Splitter IMG_3522.jpgIMG_3421.jpg

The VGA signal outputted by the multiplexer is too weak to drive two monitors. This has required video cables to be manually switched back and forth between the monitor mounted above the laser table and the desktop console.

Today I solved this problem by installing an amplifying (active) VGA splitter on the video output of the multiplexer. One output of the amplifier goes to the desktop monitor and the other to the laser table. We can now monitor the HWS realtime GUIs directly above the optical setup, with no cable swapping.

Entry  Mon Jul 22 18:46:23 2019, Edita Bytyqi, Lab Infrastructure, , Laser-Lens-HWS Setup 20190722_183933.jpg20190722_183928.jpg

Today, I set up a system consisting of the 520 nm laser, a 2'' mirror and two lenses of focal lengths f1 = 40 cm and f2 = 20 cm. The goal was to collimate the beam coming from the laser, so it goes parallel through the test optic at a radius of ~2.5 cm and then focus it to a radius of ~ 1.2 cm to fit the CCD dimensions of the HWS. The mirror was placed about 1 cm close to the laser and the first lens is setup at a distance~f1=40cm from the mirror. The test optic is placed between the two lenses and the second lens is placed about 10 cm from the CCD. The distance between the two lenses isn't important and could change in the future. The lenses and mirrors are all labeled.

I measured the approximate angle of divergence (0.06 rad) of the laser by taking the beam diameter at different positions along the propagation axis. This allowed for the ABCD matrix calculations to be finalized and the focal lengths of the lenses be chosen accordingly. 

In order to have more space in the box, I removed everything that was not necessary to the side.

Entry  Wed Jul 24 16:25:13 2019, Edita Bytyqi, Lab Infrastructure, Optics, Updated 2-lens setup 20190724_161926.jpg

The previous 2-lens setup focused the beam to a tight spot, however due to the divergence angle of the laser beam, a significant amount of power was not being captured by the fiirst lens at a distance of 40 cm from the source. The divergence angle seems to be bigger than 0.06 by a factor of 2, so a f = 20 cm lens was used to collimate the beam and a f = 30 cm lens was used to focus it. A mirror was used to reflect the beam, so we obtain steering control. Additionally, the focusing lens was placed on a small 1-axis stage in order to control the distance of the lens from the CCD, providing control over the focused beam size.

Note: The 30 cm lens was cleaned with methanol, however it still has some residue on the surface. The beam imaged to the Harrtmann Sensor looks good, however the lens will be cleaned by using a different solvent or replaced by a different 30 cm lens. The 3 lenses at the edge of the box will stay inside in order to prevent contamination, however they will not be used in the design.

Entry  Mon Jul 22 18:44:53 2019, Edita Bytyqi, Things to Buy, General, Need to Order Gloves 

Small/Medium size gloves need to be ordered in order to handle the optics carefully.

    Reply  Thu Jul 25 09:13:36 2019, Jon, Things to Buy, General, Need to Order Gloves 

New gloves are ordered for the TCS and QIL labs. They arrive tomorrow (Friday).

Quote:

Small/Medium size gloves need to be ordered in order to handle the optics carefully.

 

Entry  Mon Jul 29 18:53:16 2019, Edita Bytyqi, Lab Infrastructure, Optics, Mounted Reflector and Heater 20190729_185214.jpg20190729_185156.jpg20190729_185153.jpg20190729_185139.jpg20190729_185112.jpg

Since we set up the 2-lens system focusing the laser beam to the CCD, the next step was to mount the spherical reflector (31 mm wide) and the heater (~3 mm diameter). I used a small 3-axis stage to mount the heater, providing 3 degrees of freedom that would allow to manipulate the height of the heater, its position with respect to the reflector (left-right and in-out). The reflector was mounted in such a way that we can control its rotation angle, height and horizontal displacement. The current design is not quite sophisticated as it is just a first test, however I will look into different tools in the lab to see if I can use less mounts to get the same degrees of freedom.

The new heaters are supposed to be heated using AC. We used a DC power supply and ran ~30V through the wire, however only about ~50 mA of current was running through it. Jon will look into the specs of the new heaters to see if the power supply was the problem.

Entry  Thu Aug 1 15:20:39 2019, Edita Bytyqi, Lab Infrastructure, Optics, Reflector Mount and DC Supply 20190731_170920.jpg20190801_145836.xcf20190801_145836.jpg20190801_150635.jpg20190801_145842.jpg

Yesterday, we were able to take some data using the 120 V DC power supply. The reflectors cut at the focal point and radius were both tested; the semi-circle cut proved to give a better focus, likely because roughly half the heat is lost using the focal-point reflectors. For upcoming tests, the semicircle reflectors will be used. We varied the surface shine by using the dull and reflective side of Al foil, as well as using the machined Al itself. The best result was given by using the more reflective side of Al foil.

Figure 1 shows the steady-state surface deformation profile detected by the HWS. The heaters don't have a uniform distribution along the wire, so more heat is radiated in the center of it, thus more of it is being focused to the center of the test optic. The data needs to be analyzed to determine the radius of the focus. Our rough estimate is about ~1.5 - 2 cm. We cannot collect any more data until we get a new power supply (AC 120 V).

Today, I came up with a new design for mounting the reflectors. I used a big 3-axis stage and a small 4-axis stage. This provides 5 degrees of freedom: 3 translational and 2 rotational, which is what we need for fine-tuning the focus and directing it at different angles incident to the test optic. The only problem with this design is that the 3-axis stage is too tall for the box, so the lid won't close.There is a smaller one available, but I have to figure out a way to increase its height, since the screw size is different from the ones on the pedestals available.

Additionally, Chub used metal-to-metal epoxy to glue a screw to the back of a reflector. I will wait until tomorrow to test it, because it is a slow acting epoxy. If it works, I have the necessary tools to do the same with the other reflectors. With the current deisgn the reflector wil be screwed in to where the round screw is in the stage. If it heats up a lot and affects the material of the stages, a small optical post (top of stage) will be used to make up for the absorbed heat.

 

Entry  Tue Aug 6 19:22:28 2019, Jon, Electronics, Computing, QIL NFS server set up 

I've started building the NFS server for the QIL cymac. It's sitting on the workbench in the TCS lab next to the rack. Please don't move it or any of the parts behind it.

Entry  Fri Aug 9 20:33:11 2019, Jon, Electronics, Ring Heater, Power-regulated heater ready to use IMG_3576.jpgIMG_3577.jpg

Despite some considerable time spent, I was not able to get the Omega SCR controllers working. The first unit definitely arrived damaged. None of its LED indicator lights ever functioned, despite those on the second controller working fine under the same setup. I tried swapping in the second controller, but it has no voltage output and a red LED is illuminated which, according to the manual, means "malfunction on trigger board" or "open SCR."  Either way, the remedy is to "consult factory."

Since we have get moving with data collection, I installed a simple variable transformer (borrowed from the 40m) which steps up/down the AC voltage from 0-120 V with the turn of a knob. I soldered the leads of one of the heaters to a standard power cable which plugs directly into the transformer. I have tested it and confirmed it to work.

Entry  Mon Aug 12 21:15:12 2019, Edita Bytyqi, Electronics, , Determining heater/reflector focus 20190812_151316.jpg20190812_151258.jpg

I took images of the heat pattern projected on a piece of paper produced by the semi-circle reflector. I used 108V to drive current throught he heater. I tested the reflector without any coating and then with the dull and shiny sides of Al foil. I wasn't able to test the focal-point cut reflector because I had to glue a screw to it with epoxy which cures overnight. I will do these measurements tomorrow. Figure 2 shows the setup I used to get the data. The shiny side of Al foil is better at IR, so we will use that for the wavefront measurements.

Entry  Fri Aug 16 17:05:14 2019, Edita Bytyqi, Electronics, , FLIR Images of new reflector focusing heat 

We got 11 new semi-circle cut reflectors of radius ~3.6 cm. I glued a screw to the back of one reflector using the same epoxy as for the previous reflectors. Due to the bigger ROC of the reflector, a tight focus is achievable at greater distances (~15 cm).

Entry  Tue Sep 3 10:49:57 2019, Aidan, Lab Infrastructure, General, Exhaust duct added for new bake area in TCS lab IMG_1627.jpgIMG_1629.jpgIMG_1628.jpgIMG_1626.jpg

Facilities came in on Friday and teed off a new duct to provide exhaust for the proposed new vacuum bake area in the TCS Lab. Photos are attached. 

We installed a plastic sheet between the work area and the rest of the lab (the rest of the lab was overpressurized relative to the work area). Also, they use a vacuum when doing any drilling.

 

Entry  Wed Oct 30 12:13:14 2019, Jon, Misc, Delivery Note, New lab hardware IMG_3782.jpgIMG_3783.jpgIMG_3784.jpgIMG_3785.jpg

Ian and I moved some new hardware into the lab, shown in the below photos. It is from the shipment of loaned equipment recently returned by Whitman College. 

Attachment 1:

  • ZnSe 1" dia. lenses (x2)
  • ZnSe 38.1 mm dia. windows (x2)

Attachment 2:

  • Synrad 20 W CO2 laser
  • Synrad laser controller

Attachment 3:

  • Intraaction Model GE modulator driver
  • Intraaction AOM

Attachment 4:

  • Second Intraaction Model GE modulator driver
  • Unknown optical cavity (was packaged together with the driver)

The ZnSe lenses and windows were put in the CO2 drawer of the optics cabinet. The CO2 laser, AOM, and modulator drivers were left packaged in boxes underneath the large laser table.

Entry  Tue Jun 15 08:47:27 2021, Aidan, Lab Infrastructure, General, Cleaned up HWS table in preparation for lab move IMG_3056.jpg

I cleaned up the HWS table in preparation for replacement with the 4x10 table. We still need to move the cabinet and get the enclosure out of the way.

 

 

Entry  Tue Jul 27 08:39:33 2021, Aidan, Misc, Flood, Tuesday (27-Jul) morning check - lab looks okay Image_Pasted_at_2021-7-27_08-38-2.jpegImage_Pasted_at_2021-7-27_08-38.jpeg

I checked the lab this morning. It was dry and there wall was in the same state as yesterday.

Entry  Thu Aug 12 16:13:44 2021, Aidan, Lab Infrastructure, Flood, Carpentry shop removed wet plaster sections from the wall - it's drying for a few days IMG_4139.jpg

The carpentry shop removed wet plaster sections from the wall following the flood (process was gentle scraping of wet plaster flakes, supervised by me). The wet section of wall needs a few days to dry and then they will plaster and paint it.

 

Entry  Mon Jul 26 16:23:03 2021, Aidan, Misc, Flood, Lab flooded from broken pipe leading to sump room IMG_3881.MOV

 

Koji: QIL/TCS entrance flooding. Check your lab

Anchal: Can someone take a look at CTN too?

Koij: TCS needs more people @aidan

Koji: CTN ok

Aidan: On my way

Shruti: Cryo seems fine

Aidan: There was a leak in a pipe in the wall of B265A. It was coming from the building air conditioner condensation overflow. Facilities has fixed the pipe and is working on clean-up

    Reply  Wed Aug 25 11:28:56 2021, Aidan, Misc, Flood, Lab flooded from broken pipe leading to sump room 

11:29AM - Lab has flooded again this morning. I'm calling PMA. Looks to be the same issue as before.

Quote:

 

Koji: QIL/TCS entrance flooding. Check your lab

Anchal: Can someone take a look at CTN too?

Koij: TCS needs more people @aidan

Koji: CTN ok

Aidan: On my way

Shruti: Cryo seems fine

Aidan: There was a leak in a pipe in the wall of B265A. It was coming from the building air conditioner condensation overflow. Facilities has fixed the pipe and is working on clean-up

 

       Reply  Thu Aug 26 09:00:39 2021, Aidan, Misc, Flood, Lab flooded from broken pipe leading to sump room 20210825_-_TCS_Lab_Flood_-_compressed.pdf

Some photos of water and clean-up.

Summary: I came into the lab around 11:30AM and found water on the floor in the changing room outside QIL/TCS. Turns out the condesation overflow pipe from the AC blew out again. This time near the ceiling. Water was on the floor but also had sprayed a little onto the tool chest and East optical table. A few optics got wet on the table. Initial inspection looks like electronics were spared with the exception of the "broken" spectrum analyzer that was on the floor. 

Facilities came in and cleaned up the water. A small amount got into QIL but stayed near the door as the lab floor slopes up from the door area. They fixed the pipe and were looking into whether there was a blockage cuasing this problem. PMA was notified and John Denhart is coordinating follow-up.

Triage effort: given the AC was still active, John and I strung a temporary tarp across the two tables to block any spray.

Quote:

11:29AM - Lab has flooded again this morning. I'm calling PMA. Looks to be the same issue as before.

Quote:

 

Koji: QIL/TCS entrance flooding. Check your lab

Anchal: Can someone take a look at CTN too?

Koij: TCS needs more people @aidan

Koji: CTN ok

Aidan: On my way

Shruti: Cryo seems fine

Aidan: There was a leak in a pipe in the wall of B265A. It was coming from the building air conditioner condensation overflow. Facilities has fixed the pipe and is working on clean-up

 

 

Entry  Wed Apr 27 11:41:53 2022, Aidan, Lab Infrastructure, General, Lab clean-up to get ready for PD testing in old TCS Lab IMG_8599.jpgIMG_8598.jpgIMG_8596.jpgIMG_8595.jpgIMG_8600.jpg

We (Aidan, Koji, Radhika, Aaron) partially tidied up the TCS Lab. The front table is clean and ready to recieve PD tesitng optics, electronics and vacuum hardware. We moved all electronics units (oscilloscopes, power supplies, etc) to the rack in the NE corner of the lab. The back table was partially tidied up. We need to schedule cleaning of the remaining tables in the lab and also an inventory and disposal of obsolete equipment in all the cupboards.

 

Entry  Wed May 11 19:46:21 2022, Aidan, Radhika, Jordan, Lab Infrastructure, Vacuum chamber, Leak cleaning on IR labs vacuum chamber - suspects IMG_8812.jpgIMG_8799.jpgIMG_8789.jpgIMG_8805.jpg

[Aidan, Jordan, Radhika]

Radhika and Jordan identified some particulates (hair and flecks of foil) on the O-ring on the IR labs dewer. Additionally, we saw a scratch in the O-ring groove and a nick on the metal of the base of the dewer where it meets the O-ring. All were in the leaky vicinity previously identified by the He testing.

We set up a cradle to hold the dewer while we are working on it. Still needs vertical supports.

R & J replaced the O-ring with a new one with Crytox applied. 

Entry  Fri May 20 16:42:47 2022, Stephen, Things to Buy, Ordering, Up to Air valve for IR Labs Cryostat 

Purchased from Lesker, for venting of IR Labs Cryostat:

 - P/N C35103000 (KF10 Valve for up-to-air)

 - P/N QF25XQF10 (KF25-KF10 Reducer)

 - P/N QF25-100-T (KF25 Tee)

(to be connected in between the Chamber Tee and the Gate Valve)

Should be in next week!

Entry  Thu Jun 23 10:53:17 2022, JC, Lab Infrastructure, General, Seat For Photodiode Testing 62AE8A4B-F817-4A03-A2F1-AE48B97FB935.jpgIMG_1392_2.jpg

[JC, Chub, Radhika]

Chub and I ordered a few parts from McMaster in order build a handrail-like stopper to keep the dewar from falling over. We also cut off the excess 8020 which was leaning over the table to fit. To hold down the support for the Dewar, Radhika and I decided to use C-clamps from the EE shop.

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