I agree 100% with Juancarlos-san saying "we should be sure there are two different facts worthy of two different milestones."
1st. Essential key words of my proposal entitled "Sharp 14-inch thin-film-transistor display (-LCD) for TV , which has ushered in LCD industry" are:
3. liquid crystal display(LCD)
"another IEEE Milestone approved for the Liquid Crystal Displays, 1968" is only for LCD: neither 14-inch LCD, nor 14-inch for TV were feasible in 1968,
as is quoted below: (http://www.ieeeghn.org/wiki/index.php/Milestones:Liquid_Crystal_Display,_1968)
"Liquid Crystal Display, 1968 Princeton, NJ, U.S.A., Dedicated 30 September 2006 -- IEEE Princeton and Central New Jersey Section
Between 1964 and 1968, at the RCA David Sarnoff Research Center in Princeton, New Jersey, a team of engineers and scientists led by George . Heilmeier with Louis A. Zanoni and Lucian A. Barton, devised a method for electronic control of light reflected from liquid crystals and demonstrated the first liquid crystal display. Their work launched a global industry that now produces millions of LCDs annually watches, calculators, flat-panel displays in televisions, computers and instruments."
2nd. Below is a quote from "B.J. Lechner: History Crystallized_A First-Person Account of the Development of Matrix-Addressed LCDs_for television at RCA in the 1960s; Information Display 1/08 p26-30":
"During 1969, RCA abandoned entirely the objective of making a liquid crystal TV display: By 1969, RCA's color-TV- receiver business was matured and the smallest consumer product of significance was a 13-in. color set. Because we could not promise to compete with such a product in any foreseeable time frame, management had no interest in investing further."
In 1969, RCA abandoned LC TV because 13-inch, minimum size for TV, color LCD did not seem to be possible in the foreseeable future; in 1987, Sharp adopted 14-inch to demonstrate -LCD could be used for TV.
In 1975, Sharp started research and development work on TFT for LCD.
18 years between RCA 1969 and Sharp 1987 was required for LCD and to be developed good enough for LCD and , integrated together, to be 14-inch -LCD for TV.