Changes

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 ==

Analysis of videos taken of the vibration of the diamond wafer can lead to information about both the frequency and the amplitude of vibration.  To perform simultaneous measurements of both parameters, a precise camera calibration was necessary.

 

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 of the high temperatures on the vacuum chamber (~500 \degree C)