<div class="description">
U.S. Patent 2,594,740, filed on behalf of Lee de Forest and William A. Rhodes, describes a device for amplifying the intensity of radiation. Lee de Forest (1873–1961) was an inventor, most notably of Audion vacuum tubes in the early twentieth century. His serial business ventures included work in radio, telegraphy, telephony, broadcasting, and film.</div>
1952-Apr-29
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<li>DPLA identifier: <a rel="nofollow" class="external text" href="https://dp.la/item/38b9c1ab546725f4457e5ae5ee5b8b0a">38b9c1ab546725f4457e5ae5ee5b8b0a</a></li>
<li>Science History Institute identifier: padig:SHI-2227mq412</li></ul></span>