sound antiquated to be called a name that applies to British sailors of old,
but that name now carries a new connotation. No, it’s not related to the
practice of eating limes to prevent the vitamin C deficiency known as scurvy,
but it is related to that citrus fruit’s color.
You see, lime has just been standardized as the name and color for OM5 indoor cables.
January TIA TR-42 meeting, the optical fiber and
cable subcommittee, TR-42.12, approved an addendum to the ANSI/TIA-598 color
code standard making the color official. The decision came after just two
ballots, with the approved document achieving publication authorization without
dissention. It will be published as
ANSI/TIA-598-D-2 Optical Fiber Cable
Color Coding – Addendum 2, Jacket Color for OM5 Indoor Fiber Cables.
color is lime exactly? After all, the
name lime connotes a range of green shades. To those who understand the nuances of color
names, this lime is actually often called chartreuse. If that fancy name does not conjure up a firm
image, then think of the color of tennis balls. You know, that bright
yellow-green that makes them so easy to see.
But to be
more scientific, all the colors defined in the ANSI/TIA-598 specification are
defined using the Munsell color system.
The Munsell color space has three dimensions:
refers to the color shade, such as blue, yellow, red.
refers to color intensity, or how vivid the color appears, with a minimum of 0
and a practical maximum of about 12.
refers to the lightness. In the absence of any chroma, a value of 10 equates to
white and a value of 0 equates to black, with progressive shades of gray in
CLICK TO TWEET: It's official! Lime is the new color for OM5. It's SO CommScope's color!
is defined with a narrow hue variation just one unit wide in the green-yellow
range. It has a narrow value variation
on the bright end of the range, set between 8 and 9. And it has high chroma, with a minimum of 8
and unlimited maximum. All of this means
that lime is well separated from neighboring colors of yellow and green, also
defined in ANSI/TIA-598. So, this lime
is very distinctive.
proposed this color for OM5 to set it apart from its predecessors, OM3 and OM4,
which are colored aqua for both cable jacket and connecting hardware. Following this precedent, it would be most
intuitive to have OM5 connecting hardware match its lime jacket. That’s a decision to be made in the first addendum
to ANSI/TIA-568.3-D, the fiber and component structured cabling standard, now
in its second ballot.
color distinction signifies that OM5 is the first multimode fiber cable with
laser-optimized bandwidth characteristics specified to cover wavelengths in the
850 nm to 950 nm range in support of short wavelength division multiplexed
applications, such as 40G-BiDi, 40G-SWDM4, 100G-BiDi, and 100G-SWDM4, each
capable of delivering those high data rates over a single pair of fibers. This
great advancement in transmission capacity of MMF makes me happy there is a new
limey in town!