|From the Greek, Uni meaning one and lens meaning lens.|
But then things took a turn for the worse. Crews complained that the small internal lamps didn't provide a bright enough light and the lamps themselves were proprietary, expensive and prone to burning out.
|You be the judge!|
I am posting this because while passing by the BART Millbrae station I observed that the goose-neck Unilens signals, perhaps some of the only examples ever purchased for rapid transit, had been swapped out for bland and boring LED traffic light type signals. No the Unilens isn't going the way of the position or searchlight signal. CSX, SEPTA and BNSF still prefer them in close clearance signaling locations across their systems, but as a replacement for what was once the most common signal type in North America if not the world, the Safetran Unilens has fallen dismally short.