Do you remember when it seemed like every motherboard RAM module and adapter card out there was green?
Well, these days they often come in other colors to be more aesthetically pleasing,
with black being the most common. But even now, many circuit boards across a wide
variety of electronics retain that classic green color. But why is green so prevalent?
It certainly isn't because these big electronic companies are secret environmentalists.
So what's the real reason? Well, there's actually not a single reason that everyone agrees on.
But one major contributor is a layer on the PCB called the solder mask. As the name might imply,
solder mask is a lacquer that protects the board against oxidation. Very important for electronics,
as well as prevents different pieces of solder from accidentally touching each other and causing a
ShortCircuit. Some of the materials used in solder mask, especially in the early days of
electronics manufacturing, had a natural green hue to them since they contained glass epoxy.
And you need only look at an old coke bottle to see that glass often has a bit of a green tint.
At some point, though, manufacturers started to augment this natural green with green dye.
One reason is that despite the glass epoxy, PCBs still had a rather unappealing brown color,
even though they made numerous attempts to recolor the board. Through trial and error, though,
they were able to turn the board into a less offensive shade of green that wasn't so god-awful
to look at. But of course, people showing off exposed PCBs is a relatively recent phenomenon.
Before the era of glass and acrylic computer cases, most people who stared at circuit boards
for long periods of time were hobbyists, engineers, and quality control workers who needed to see
the individual traces clearly. A green background provides a strong contrast for the gold and copper
traces, as well as for the text that labels individual components, which is usually white
to reduce mistakes and catch production errors before they make their way to consumers.
Green is also a color our eyes are relatively sensitive to, but doesn't tend to be fatiguing
over long periods of time the way yellow and red can be, which matters for professionals who stare
at PCBs all day. There's a related argument that green boards also have higher yields,
meaning they experience fewer errors in production. Conversely, this has also been floated as a reason
why white PCBs are harder to find. The materials used in green solder mask actually allowed board
components to be spaced closer together than some other colors, reducing errors on densely packed
PCBs. Another popular hypothesis is that the US military had their hands on making the PCBs green.
Obviously, militaries around the world have long favored green for its ability to camouflage
soldiers and equipment, but it turns out that the American military actually had multiple patents on
PCBs back in the early days of electronics. And of course, it would make sense that if soldiers
were lugging electronics around in the field, it would be far better to blend into the rest of
their equipment, and thus their environment, than, you know, some shade of orange that would
effectively serve as a bullseye for an enemy sniper. But regardless of which of these reasons
was the primary driver of green becoming an industry standard, the ubiquity of the green
circuit board has also led it to become an inexpensive option since green PCBs can be produced
in bulk further contributing to its popularity. Of course, manufacturing has improved over time,
and nowadays it isn't too hard to order a PCB in a different color. And if we're talking mother
boards, I mean, good luck even finding a green one anymore if you're trying to build your own
computer. I guess you could always throw some fake plants inside your case and turn it into an
AirSets terrarium if you really miss green. Thanks for watching guys. Like, dislike,
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