One of the last technological efforts to change the picture tube (CRT) to save space was to move the scanning area (the part you see) from a front face to a face on the rear and project the picture out. This would allow the tube to be thinner as the neck of the CRT and the screen would be on the same plane. The concept was demonstrated in the 1960's, but Sony perfected the concept to allow mass production of handheld, truly portable line of tv's called the Watchman. All Watchmans were black and white or monochrome. Some Watchmans became mini "boomboxes" which included am/fm stereo radios, an alarm clock and even featuring a cassette recorder. Most Watchmans used AA cells which made them lightweight. The emergence and advances in liquid crystal displays (LCD) ended the Watchman's life as a product. Sony would drop the CRT in the early 1990's due to advancements in color LCD panels, and introduce the Color Watchman which were all LCD. The LCD allowed all Watchmans to be pocket size, like transistor radios were in the late 1950's.
The First Sony Watchman Model FD 210 (1982) 1.5 inch DIAG CRT