Here’s an early 1970s portable terminal with fantastic looks, which might be rightfully called the “Polaroid SX-70” of terminals. Sadly, I wasn’t able to put a date to this. The artifact in question (sadly not mine) is the ADDS Envoy Traveling Terminal 600. The Envoy 620, which is also pretty stunning (see below) was introduced in June 1972. (Since this is looking a bit early, it may be 1970/71.)
The ADDS Envoy 600, a sales brochure (PDF) can be found at archive.org.
And here’s the ADDS Envoy 620:
For more info and images see https://terminals-wiki.org/wiki/index.php/ADDS_Envoy_620 and http://jimsoldtoys.blogspot.com/2016/05/adds-envoy-portable-terminal.html on the similar ADDS Envoy 580.
terminals-wiki.org writes on the company history:
“Applied Digital Data Systems, or simply ADDS, was a manufacturer of high-quality video terminals. In March, 1979, ADDS had delivered 100,000 CRT terminals. In 1980, ADDS became a wholly owned subsidiary of NCR. In 1991, ADDS become part of AT&T when AT&T purchased NCR. In 1994, AT&T sold ADDS to SunRiver Data Systems. In 1996, the company was renamed to Boundless Technology.”
P.S.: A nice source found in one of these pages, providing a comprehensive overview of 1970s terminals, is the “Handbook of interactive computer terminals” by Duane E. Sharp, 1977, available as a PDF at https://archive.org/details/handbookofintera00duan.