I've always seen the English translation of this title as Purple Noon. That's how it was listed at the place from where I rent DVDs. But its French title, Plein Soleil literally translates to Full Sun.
How does this title apply to the movie? Is there such an expression as "purple noon," and if so, what does it mean?
Normand Holland, in his essay on the film, wrote:
Incidentally, the French title means “full sun,” or “bright sun,” referring I think to the clarity of things at sea. The strange English title, “Purple Noon,” comes from a poem by Shelley that contrasts the poet’s dark mood with the bright sea and sunshine. In the same way the film contrasts Tom’s dark scheme with the bright Mediterranean sea and sky marvelously photographed in gleaming Eastmancolor by cinematographer Henri Decaë. Out there things are clear; on land they shift and turn mysteriously.share
Nice catch!
Stanzas Written in Dejection, near Naples
The sun is warm, the sky is clear,
The waves are dancing fast and bright,
Blue isles and snowy mountains wear
The purple noon's transparent might,
The breath of the moist earth is light,
Around its unexpanded buds;
Like many a voice of one delight,
The winds, the birds, the ocean floods,
The City's voice itself, is soft like Solitude's.
There is, of course more, but easily found...