I'm not sure if this has been discussed before, but it has intrigued me for years. What I'm referring to is the computer display seen at the science aboard Constitution-class refit vessels, specifically the Enterprise science station. Here is the science station as seen in The Motion Picture, as Spock voices his suspicions about an object at the center of V'Ger. The display just over his left shoulder has a "honeycomb" appearance. Here is the science station in The Wrath of Khan. The "honeycomb" is again visible just behind Spock, as he scans for signs of a chamber's coil malfunction. Here is the station at the outset of The Search for Spock. As Spock is absent due to his death in The Wrath of Khan, Chekov has taken over his duties. The display now has more a red appearance, though the "honeycomb" pattern is still visible. Here is the station later in the film, seen moments before the Enterprise's confrontation with the Klingons above Genesis. The display now has a dark blue appearance.