In the Netherlands the predecessor to the Philips SRS201, the Philips SRM, can still be quite commonly found.
These lanterns were produced in the 1960s and 1970s. The SRM could take either a 90W or 135W SOX lamp, and the longer SRL could take 180W SOX. They were available either with clear or refractored bowls.
A few of you will recognise this location. The former A2 Lekbrug motorway bridge south of Utrecht, now bypassed by a much larger motorway bridge to the west. The old Philips SRM lanterns proudly stand abandoned on the bridge.
A close up. The closest lantern has a refractor bowl whilst the other lantern has a replacement clear bowl.
The slip roads to the motorway crossing the new bridge are lit with Philips SRS201s running 135W SOX lamps, mounted on stepped aluminium hockeystick columns. Installations like this are very common on motorway slip roads in the Netherlands, often with 90W and 135W SOX lamps and occasionally with 180W SOX lamps. Most motorway and slip road SOX lanterns are remote geared. Whilst new lighting installed on Dutch motorways is generally SON there have been a number of recent SOX installations on slip roads, and don't be surprised if you see shiny new aluminium columns with shiny new remote geared SRS201s.
An Innolumis Lumis LED lantern. In years gone by LED technology was not as efficient as it is today, and using white LEDs did not offer a power saving over conventional discharge lamps. The company Innolumis then came up with the scientific idea of producing light at a part of the spectrum that the human eye is sensitive to. They produced two variants in the past, the Green, which was fitted with green LEDs, and the EcoWhite, which was fitted with a mixture of red and green LEDs. By producing pure monochromatic green light they were able to make lighting levels appear brighter with lower wattages in comparison with using white LEDs. However, monochromatic light is not always desirable, so introducing some red LEDs brought in some slight colour rendering. However, using a mixture of red and green LEDs is not as efficient as using purely green LEDs. We have previously seen red and green LED versions in Plymouth, and now we have seen the Green LED versions.
I had to play around with the images a bit to make the green colour more accurate. The light is a vivid apple green, and it is quite effective. Obviously, white LEDs are much better now than they were, but it was interesting to see this innovation.
More to come later.