Imaging and entertainment technology in use during the 4th and 5th centuries AT.
A basic reality room used a combination of full-surround optical phased-array displays, high fidelity sound generators, and virtual reality "touch link" haptic interfaces to create the illusion that the user was actually experiencing any environment that had been properly recorded or generated by a sufficiently powerful computer. More advanced versions of the technology also included specialized scent generators using stored chemicals to produce odors such as might be found in a particular scene or locale that was being displayed (although critics pointed out that more often than not the odors produced had more to do with what the producers of an experience thought the user would smell in such a situation than what they really would). At the very highest level of sophistication large entertainment venues, educational and research institutions, or government and corporate simulation centers would employ early ufog based "smart matter" shapes extruded from hidden vents in the chamber as well as subtle optical and sonic tricks to fool the user into feeling like they were "really" there (wherever there might be).
By the time of the Technocalypse reality room technology had progressed to the point where most middle class individuals could afford a basic system for a significant investment, although there was sharp competition from the older, and rather cheaper, "pure" virtual reality systems already widely available. The more sophisticated versions of the technology were still mostly beyond the means of the average private citizen. It was widely expected that this would change over time in much the same way that the "home theater" systems of the early Information Age progressed from being toys for the rich technophile to common accessories in many homes.
The Technocalypse put an end to all such developments however, and for several centuries thereafter reality room technology was either lost or mostly limited to purely functional applications with no consideration given to entertainment value. A primary application of the technology — usually found in larger, more advanced communities — was to provide a full-immersive perimeter monitoring platform for security personnel. Inputs from hundreds or thousands of sensors, ranging in scale from kilometers to nanometers, could all be combined in a full-surround simulation converting multiple data streams into visual, aural, tactile, and even olfactory information flows. Such devices required extensive user training to be fully effective, but were considered worth the effort when the alternative could be the deaths of thousands.
More in keeping with the original intent of the reality room was its (very) occasional application in some of the smaller habs and settlements as a tool of reward or special recreation. In these cases top workers might be rewarded with short "visits" to other times and places or newlyweds might get to celebrate their wedding night in some fantasy locale generated via a reality room within the community. Often these rooms were antique holdovers from the pre-Technocalypse period, originally installed as some rich being's toy and then painstakingly maintained by the surviving inhabitants as a small reminder of better times past. A rather darker application of the technology was as a tool of indoctrination by some cults or local leaders who used the reality room to help brainwash or otherwise convert potential recruits to their cause. Fortunately, such events were quite rare, largely as a result of the scarcity of such devices in the first place, but dark stories of that time can still be found in most archives.
It was not until the rise of the First Federation that attention again turned to the technology's potential to educate and entertain, either individually or en masse. For a time it seemed that the reality room would be making a comeback, but it was not to be. Further development of utility fog-based technologies, continued advances in DNI-mediated virtual reality and eventually the first angelnet systems reduced the reality room to a quaint curiosity. The older systems proved far too bulky and limited to be used by anyone except collectors of antique technology or the occasional curious dilettante who wanted to see how eir "primitive ancestors" lived during the dark ages.