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<p>Hello all,</p>
<p>I have analyzed the thickness analysis of mirror 4C in
Mathematica using the data from the CMM measurements taken last
week. The analysis for the other three mirrors is in process.</p>
<p>Attached are the following images of mirror 4C:</p>
<ol>
<li>Edge measurement points plotted in NX 9.0.</li>
<li>Mirror surface and back surface measurement points plotted in
NX 9.0.</li>
<li>Edge measurement points plotted in Mathematica.</li>
</ol>
<p>For the mirror and back surface NX 9.0 plot, the back surface is
in red and the mirror surface is in blue.<br>
</p>
<p>For the Mathematica plot, the mirror edges are plotted in red and
the back edges are plotted in blue.</p>
<p>I have also calculated the mean thickness and standard deviation
of each side of the mirror. The table of results is below.</p>
<table height="149" border="1" cellpadding="2" cellspacing="2"
width="471">
<tbody>
<tr>
<td align="center" valign="top"><b>Side</b><b><br>
</b></td>
<td align="center" valign="top"><b>Mean Thickness [mm]</b><b><br>
</b></td>
<td align="center" valign="top"><b>Standard Deviation [mm]</b><b><br>
</b></td>
</tr>
<tr>
<td align="center" valign="top">Right<br>
</td>
<td align="center" valign="top">25.338<br>
</td>
<td align="center" valign="top">0.273<br>
</td>
</tr>
<tr>
<td align="center" valign="top">Left<br>
</td>
<td align="center" valign="top">25.193<br>
</td>
<td align="center" valign="top">0.529<br>
</td>
</tr>
<tr>
<td align="center" valign="top">Top<br>
</td>
<td align="center" valign="top">25.784<br>
</td>
<td align="center" valign="top">0.621<br>
</td>
</tr>
<tr>
<td align="center" valign="top">Bottom<br>
</td>
<td align="center" valign="top">25.471<br>
</td>
<td align="center" valign="top">0.571<br>
</td>
</tr>
</tbody>
</table>
<p>In addition, I have also calculated the difference in mean
thickness for each side and the error of the difference.</p>
<table height="207" border="1" cellpadding="2" cellspacing="2"
width="496">
<tbody>
<tr>
<td align="center" valign="top"><b>Sides</b><b><br>
</b></td>
<td align="center" valign="top"><b>Difference in Mean
Thickness [mm]</b><b><br>
</b></td>
<td align="center" valign="top"><b>Error [mm]</b><b><br>
</b></td>
</tr>
<tr>
<td align="center" valign="top">Left - Right<br>
</td>
<td align="center" valign="top">0.145<br>
</td>
<td align="center" valign="top">0.596<br>
</td>
</tr>
<tr>
<td align="center" valign="top">Left - Top<br>
</td>
<td align="center" valign="top">0.591<br>
</td>
<td align="center" valign="top">0.817<br>
</td>
</tr>
<tr>
<td align="center" valign="top">Left - Bottom<br>
</td>
<td align="center" valign="top">0.278<br>
</td>
<td align="center" valign="top">0.779<br>
</td>
</tr>
<tr>
<td align="center" valign="top">Right - Top<br>
</td>
<td align="center" valign="top">0.446<br>
</td>
<td align="center" valign="top">0.679<br>
</td>
</tr>
<tr>
<td align="center" valign="top">Right - Bottom<br>
</td>
<td align="center" valign="top">0.133<br>
</td>
<td align="center" valign="top">0.632<br>
</td>
</tr>
<tr>
<td align="center" valign="top">Top - Bottom<br>
</td>
<td align="center" valign="top">0.314<br>
</td>
<td align="center" valign="top">0.844<br>
</td>
</tr>
</tbody>
</table>
<p>From these results, I think the mirror thickness is uniform. The
thicknesses are ~1 [mm] of the thickness specified by the mirror
manufacturer.</p>
<p>Note the survey equipment, per Jim Dahlberg, has a resolution of
60 [um].<br>
</p>
<p>After the thickness analysis of the other three mirrors is
complete, I will determine the radius of curvature from the CMM
measurement points.</p>
<p>Best regards,</p>
<p>Tyler<br>
</p>
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