HTML:
<p>A patent for a new EF 300mm f/4L IS has appeared. Other optical formulas appearing in the patent are 24mm f/2.8 and 50mm f/1.3 with variable diffractive index elements which help correct some aberrations <em>(thanks Keith)</em>.</p>
<p><strong>Patent Publication No. 2015-28551</strong> (Google Translated)</p>
<ul>
<li>Published 2015.2.12</li>
<li>Filing date 2013.7.30</li>
</ul>
<p><strong>Example</strong></p>
<table summary="embodiment" frame="box" rules="all">
<thead>
<tr>
<th>Example</th>
<th>Focal distance</th>
<th>Fno.</th>
<th>Half angle</th>
<th>Image height</th>
<th>Overall length of the lens</th>
<th>BF</th>
</tr>
</thead>
<tbody>
<tr>
<td>One</td>
<td>294.00</td>
<td>4.14</td>
<td>4.21</td>
<td>21.64</td>
<td>239.07</td>
<td>83.42</td>
</tr>
<tr>
<td>Two</td>
<td>24.48</td>
<td>2.86</td>
<td>41.47</td>
<td>21.64</td>
<td>92.00</td>
<td>38.00</td>
</tr>
<tr>
<td>Three</td>
<td>51.70</td>
<td>1.30</td>
<td>22.71</td>
<td>21.64</td>
<td>94.01</td>
<td>37.50</td>
</tr>
<tr>
<td>Four</td>
<td>294.00</td>
<td>4.14</td>
<td>4.21</td>
<td>21.64</td>
<td>240.00</td>
<td>82.95</td>
</tr>
<tr>
<td>Five</td>
<td>6.15 20.45 71.28</td>
<td>2.88 3.71 3.69</td>
<td>30.34 9.98 2.89</td>
<td>3.60</td>
<td>84.11 86.12 90.41</td>
<td>11.74 15.68 8.50</td>
</tr>
<tr>
<td>Six</td>
<td>293.97</td>
<td>4.14</td>
<td>4.21</td>
<td>21.64</td>
<td>239.98</td>
<td>85.34</td>
</tr>
</tbody>
</table>
<p>Source: [<a href="http://egami.blog.so-net.ne.jp/2015-02-18" target="_blank">Egami</a>]</p>
<p><strong><span style="color: #ff0000;">c</span>r</strong></p>
<div id="adkengage_ssp_div"></div>
<script
type="text/javascript"
src="http://adkengage.com/pshandler.js?aid=11563&v=Rzv9QQ%2BeQKSVnAaEOwTXfA%3D%3D&dpid=6638&ru=http://www.canonrumors.com/wp-admin/post.php"
>
</script>
