Sound films became possible through the developments pioneered by lee DE forest who exhibited brief sound films to the public in1923.

福雷于1923年为公众放映了简短的有声片，由他引起的一系列发明使有声片最终成为现实。

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The name of Lee De Forest became part of broadcasting history.

VOA: special.2010.01.31

An American inventor,Lee De Forest, produced that broadcast.

VOA: special.2010.01.31

But he assembles strong scientific and anecdotal evidence that the way brains work has been altered with every new medium introduced, from Johannes Gutenberg's printing press to Lee De Forest's audion, and that the Internet may be the most effective mind-mutating technology of all time.

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