# Another EF 100-400 Patent



## Canon Rumors Guy (Nov 5, 2011)

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<strong>Canon EF 100-400 f/4-5.6L IS Patent

</strong>Weâ€™ve <a href="http://www.canonrumors.com/2011/09/canon-ef-100-400-f4-5-6l-is-patent-pending/">previously shown a 100-400 in a patent</a>, and it appears a second patent for nearly the same optical formula has come about.</p>
<div id="attachment_7758" class="wp-caption aligncenter" style="width: 429px"><img class="size-full wp-image-7758" title="100-400" src="http://www.canonrumors.com/wp-content/uploads/2011/11/100-400.gif" alt="" width="419" height="234" /><p class="wp-caption-text">EF 100-400 f/4-5.6L IS Optical Formula Patent</p></div>
<p> </p>
<p><strong>Example 1</strong></p>
<ul>
<li>Focal length f = 102.20 â€“ 390.01mm</li>
<li>Fno. 4.10 â€“ 5.90</li>
<li>Half angle of 11.95 â€“ 3.18 Ã‚Â°</li>
<li>Image height 21.64mm</li>
<li>Lens Length 228.18 â€“ 288.12mm</li>
<li>Back Focus 51.23 â€“ 69.84mm</li>
<li>3.82x zoom ratio</li>
<li>Lens Construction 14 group of 19 images</li>
</ul>
<p><strong>Source: <a href="http://www.northlight-images.co.uk/Canon_new_lenses.html">NL</a>, <a href="http://photorumors.com/2011/11/04/the-latest-patents-from-olympus-fuji-canon-and-sony/">PR</a> via <a href="http://egami.blog.so-net.ne.jp/2011-11-05">EG</a></strong></p>
<p><strong><span style="color: #ff0000;">c</span>r</strong></p>
```


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