Wikipedia
AlphaWindows was a proposed industry standard from the Display Industry Association (an industry consortium in California) in the early 1990s that would allow a single CRT screen to implement multiple windows, each of which was to behave as a distinct computer terminal. Individual vendors offered products based on this in 1992 through the end of the 1990s. and after,
These products were targeted at a low-end market: "for users that don't need the processing power of a personal computer or the complexity of an X Window terminal, the AlphaWindow terminals and software provides the same look and feel of windows-based graphical user interfaces on an Alphanumeric terminal".
The initial concept relied on custom (but low-cost) terminals which would support mouse interaction, (text) windowing support, and colored text. With that, plus special host software, the vendors proposed to support semi-graphical applications "transparently".