Thanks PG101 for this interesting information about the first LCDs (DSMs looking like FEs displays?!??) with 8 digits.
I did not responded sooner because I needed to document a little these amazing 1972-1973 8 Digits watch prototypes.
So what I've found is that - basically - BOTH the Longines and Brown Boweri was about the same thing produced in 1972-1973 by Ebauches SA (=ESA) in two different collaboration:
I. (n.r. for sure a DSM - Dynamic Scattering LCD!) made by Ebauches S.A. (ESA)+ Texas Instruments (integrated circuit!) + LonginesCaliber ESA 9260 of the 'Swissonic 2000' line, produced by Ebauches S.A. (ESA), Longines and Texas Instruments (n.r. probably the IC!) with the name 'Clepsydre' reaches the market. Only very few watches were sold by Longines. In 1972, this watch won a prize as one of the hundred most advanced products of the year 1972, awarded annually by the 'Annual Research Conference and Awards'.https://doensen.home.xs4all.nl/l1.htmlPlease note that Doensen's book have mentioned that "Only very few watches were sold by Longines." while Hyltin book (1978) - The digital Electronic watch mentioned at page 8 that the Longines watch was not built "in production quantities" - THUS we may talk probably about some prototype/demo watches for International Exhibitions!
II. Probably also a DSM module - made by Brown Bovery + Ebauches SA (ESA) + Philips/Faselec (Integrated Circuit) [i]"Prototype displays were made for a joint-effort wristwatch project that we did together with Ebauches SA, the major Swiss watch movements manufacturer (now part of the Swatch Group) and Faselec (n.r. the IC), the Swiss IC subsidiary of Philips. A working quartz digital wristwatch was shown at the MUBA fair in March 1973. It contained chips made by Faselec and our 8-digit TN LCD."[/i]
http://ethw.org/First-Hand:Liquid_Cryst ... tributionsThe only thing that it should be also clarified is WHY both those above mentioned 8 Digits prototypes may look more like a more modern FE LCD display than a DSM display (black digits on white screen, instead of creamy white digits on a black displayas regular DSM display!
And the EXPLANATION is that - while it is not very known - ALSO the DSM LCD could be used not only in "reflective mode" (using a mirror) - as most other DSM displays, but also by using a "black back plate" when the digits may look BLACK on a white screen, as one may read below, on the Doensen Book: "The surrounding light goes through the front glass, a liquid crystal layer of 0,025 mm thickness, and is absorbed in the black back plate. On both glass plates, conductive transparent electrodes are attached. When a voltage between 10 and 20 volts is applied on the electrodes, the arrangement of the molecules is destroyed by the collisions of the moving ions, scattering the light and causing this part of the LCD to look darker than the rest of the display.
By replacing the black plate by a mirror it is possible to use the cell in a reflective mode. The segments which are not energised let the light go past, which will cause the mirror to reflect the light and compose the digits. The layer in the electric field between the electrodes scatters the light in all directions and looks dark. When no voltage at all is applied, the display is clear and the parts which are mirrored can be seen. The latter display has been applied the most. "https://doensen.home.xs4all.nl/l1.htmlas one may see in the picture below ( Hyltin book (1978) - The digital Electronic watch ):
04 May 2017, 21:46
