Originally posted by thibs Pentax always had nice technologies/particularities which they never marketed. Remember the marketing tornado because the new AF-D Nikkor lenses were reporting distance information to the camera? Well Pentax did it long before.
What Pentax did not however (stupidly) was to use that info for others uses than TTL Flash. But lenses starting from FA (or was it F?) could do this.
F lenses had distance info, yes from 1987.
MTF-chip came in the FA lenses from 1993, but was also featured in the newer F-lenses (which actually were FA lenses but without powerzoom, and just to confuse everyone Pentax finally made FA lenses without powerzoom and called them FA!).
The distance info was used by the multisegment metering. It was, funny enough, not used by the TTL flash until P-TTL came. And it was used by P-TTL because P-TTL uses the multisegment metering, which read the distance info..
Distance info was also used by the clever Smart Picture Modes, later renamed to Auto Picture Modes. This was another Pentax first (auto-selection of picture modes).