Back in 1939, the future was all about watching TV with one eye!

The March 1939 issue of Radio-Craft magazine description:

In England, the Gramophone Co. (Middlesex) last month announced the Television Monocle, says Radio-Press-Service. Held like an ordinary French-phone, it affords “personalized” television image and sound reception. This H.M.V.—His Master’s Voice—Television Monocle presents an image about 1.5 x 1in. (which is about all the eye can accommodate at such short range), as viewed on the second of 2 mirrors at 45-deg. angles; the cathode-ray tube is actuated by a nearby receiver. The earpiece at the end of the Monocle completes this televiwer for the “rugged individualist.”