Indeed, the first LED retrofit lamp I saw in use were the tubular exit sign ones with 5mm red or green LEDs. The oldest LED retrofit lamp I have personally dates to the early 90s I think - it's a 12V MR16 bipin base and uses a cluster of 5mm red LEDs. In the early 2000s I bought some early Lights of America PAR30 CFLs that used 6500K 5mm LEDs. It looks like a showerhead. One has been in nightly use for 14 years now on a timer, so it's surpassed the 30,000 mark and all diodes are still working, just very dim and yellowed out. I also bought some early A19 LEDs of various styles and one of the heavy metal case R20 GE LED spotlights around the same time, and some early SMD low-voltage flashlight and landscape bulb retrofits that put out barely any usable light. Maybe the absolute worst I remember were the plastic base "Meridian" C7 nightlight retrofit LEDs that used a single 5mm LED. They were just about useless in terms of light and failed by literally burning up...not a good design.
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I'm lampin...