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Construction of a Tabletop Michelson Interferometer (view source)
Revision as of 20:38, 9 June 2011
, 20:38, 9 June 2011→Parts List
| || Kinematic Mirror Mount || Adjustable Kinematic mount for 1" holder
| || Kinematic Mirror Mount || Adjustable Kinematic mount for 1" holder
|-
|-
| Light Source || 532nm Green laser Module || 5mW, 5mm spot size, <1.4 mrad div.
| Light Source || 532nm Green laser Module [[Media:5_milli_watt_circuit.pdf|Circuit Layout]] || 5mW, 5mm spot size, <1.4 mrad div.
|-
|-
| || Kinematic V-Mount || Small Mount with Attached Clamping Arm
| || Kinematic V-Mount || Small Mount with Attached Clamping Arm
| Safety Equipment || Laser Safety Glasses || Green and Blue laser beam protection
| Safety Equipment || Laser Safety Glasses || Green and Blue laser beam protection
|}
|}
=== Estimating Camera Sensitivity ===
=== Estimating Camera Sensitivity ===
It is crucial that any spherical aberration are removed by way of pinhole. The laser spot is passed through a pinhole, which acts to expand the beam. This expansion creates a patter known as an [http://en.wikipedia.org/wiki/Airy_disk Airy pattern]. To correctly remove the spherical aberrations, the beam must be expanded such that the only the first ring is sent through the second lens, and the rest is blocked off. To determine the proper pinhole size for the design, [[Huygens Principle for a Planar Source|the following analysis was performed]].
It is crucial that any spherical aberration are removed by way of pinhole. The laser spot is passed through a pinhole, which acts to expand the beam. This expansion creates a patter known as an [http://en.wikipedia.org/wiki/Airy_disk Airy pattern]. To correctly remove the spherical aberrations, the beam must be expanded such that the only the first ring is sent through the second lens, and the rest is blocked off. To determine the proper pinhole size for the design, [[Huygens Principle for a Planar Source|the following analysis was performed]].
== Camera Calibration ==
== Design of a mounting device for diamond surface analysis ==
During the last test as [http://www.chess.cornell.edu/ CHESS] it was determined that the wire mount was not suitable for diamond analysis because the rocking curve was skewed by the high vibrational frequency of the diamond-wire system. In order to perform the surface analysis, a new mounting device is in development.
[[Image:Mylar mount.jpg|center|Mount which will be used at the next run at CHESS]]
This device is composed of two stretched mylar sheets with each sheet attached to one half of the mount. The diamond will be placed between the sheets. This advantage of this type of mount is that it will create very little stress on the diamond sample, preventing the sample from warping. This type of mount cannot be used in the final beam path at JLab because the high temperatures in the vacuum chamber (~500<sup>o</sup>C) will deform the mylar sheets.
In order to use this mount in the diamond analysis, the center area of the mylar must be sufficiently flat. To ensure this flatness, a large sheet of mylar (100 <math> \mu m</math>, most likely 24" x 24") will be placed over and attached to a drum with an 18" diameter. The large diameter will ensure that any small wrinkles at the edges will not propagate all the way to the center region. The mount will then be glued to the mylar and while the glue is still tacky, the mylar will be stretched. The mylar will be stretched by placing a weighted container (approximately 100 pounds) on top of it. To verify that the center region is flat, the mount will be placed in the interferometer, and the interferogram will be analyzed using the process found [http://zeus.phys.uconn.edu/wiki/index.php/Analysis_of_Michelson_interference_images here]. This will give us an image of the surface of the mylar.