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What deflection do we want? For Auxtel the FOV is about 6 arcmin. From center to side it's 2000*0.1 arcsec = 200 arcsec = 3.33 arcmin. So a deflection of 2 arcmin seems decent. If we're 4m away from primary, spot is displaced by only 2mm.
Problem with this config is beams are not very separated, spatially. We need a precision periscope on some to get more displacement.

Meghan Notes

Mac mini control system

newport - start reading control manual for 2 degrees of freedom setup
system will now have beam splitters
- do beamsplitter mapping
- look at alternatives and categorize
clear a workspace
~~come up with plan and deadlines~~

SEMESTER PLAN:

end of Jan - conceptual design review complete
- Tasks for Meghan
  - make a 4-5 slide slide deck where I make pictures describing the system (include part numbers, make list)
  - software architecture plan for controlling the mounts (can do during the lead time for hardware)
    - read control manual for whatever mount setup we order
    - If the adjustable hardware impeding timeline we abandon
  - Place beamsplitter order and put below deadlines on calendar

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Prototype one single collimated beam that we can steer around
Optical source and control the light on/off (engineering milestones)
Then, we scale this up to six steerable beams
Then test these six beams on a telescope that we have HERE to test input (tight-beam demonstration)
check in with telescope mounting after prof. stubbs trip (phone app that captures inside of telescope dome/Mario's Solidworks model)

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Meghan will create a detailed presentation (4-5 slides) describing the system we are to build and its purpose, and be as detailed as possible (including part numbers).

Meghan will then present this slide deck to Prof. Stubbs and Elana - we will find a time hopefully before Friday Feb 2.

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Meghan and Prof. Stubbs will decide on:

optical mounts for the beamsplitter cubes
type of computer hardware to control the optical mounts
begin a bill of materials

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Have a single, steerable collimated beam working. This will involve:

mount the beamsplitter on its adjustable mount and standardize this mounting system
mounting the light source and a single beamsplitter on the rail, and align them so that light goes through the beamsplitter (will be off-axis)
beam will be correct size (2") and collimated
there will be working software that is able to control where the beam is pointing
we can turn the beam on and off with software

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Add the other beamsplitters so that the system is scaled to its full size.

mount other beamsplitters on rail in correct order ~~and align so that all beams are of roughly equal intensity~~ we can only get 50:50s
do steering tests on all beams to make sure all parts are working properly

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Set up the system for the telescope we have here to test the differential monitoring.

will need the beams to be relatively close together

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preferably before

Friday, April 26

but there is some wiggle room

Initial steps:

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Beamsplitter options, CWS Jan 26 2024

vendor	part #	size	specs	price
Newport	20BC17MB.1	50.8 x 50.8	lambda/4	$635, stock
Edmund	#32-704	50.0 x 50.0	lambda/4	$539, stock
Thor	BS031	50.8 x 50.8	lambda/4	$564, stock

Alignment:

CWS Jan 27 2024

If we use bounced-back beam from front face of beamsplitter cube, or else retro-reflected return beam, what displacement corresponds to what angle?
Assume 50 cm distance from cube face to detector. If we want to align to 5 arcmin (size of a Rubin detector) then the angle is 5*60*5e-6 rad = 1.5 mrad.
That is a spot displacement of 1.5E-3*50cm = 7.5 mm. So a detector 10mm on a side would be good for this. Thor labs 126MU camera is 14mm x 10mm.

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If we send the beam down to a corner cube and back again, that allows for in situ alignment, with a flip-into-beam beamsplitter.

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camera:

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Camera software:

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Flippers:

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3/8 inch diameter micrometer mounting is compatible with Thor Labs Piezo PIAK10 actuators

This Newport stage is too. We'd need two in order to steer each beam.

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The other alternative is Thor labs small tip-tilt stage

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After considerable looking around for an off-the-shelf way to control 6 different tip-tilt platforms, arrived at this from Newport:

Nope- inadequate force from actuators. Didn't order this.

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Acronym options

Multi-beam Optical Seeing Sensor- MOSS
Precise Emitter of Aligned Rays - PEAR
Parallel Aligned Ray Projector- PARP
Parallel Photon Projector- P-cubed
Laser Light Aligned Multibeam Apparatus- LLAMA