Since only visible light and not electricity is "piped" to where it is needed, Fiber optic lighting technology is the safest illumination approach in and around water. Its light source, typically an electrically charged lamp, is placed at some convenient but out-of-the-way location and only optical fibers themselves extend to the target to be illuminated.

A fiber optic lighting system's design is also relatively simple. Its light source, typically a high output lamp with a focusing optic, is connected to some length and diameter of flexible optical fibers that have been bundled together.

When the lamp is tuned on, light gets applied to one end of bundled fibers carrying illumination within its full length until exiting out the other end. This fiber bundle, generally protected by an opaque sleeve that forms a single cable, is laid along a desired path and its end brought to a target requiring illumination.

Since the cable is both flexible and relatively small in diameter (less than an inch), the light it channels can be brought to nearly any location (places of extreme temperature not included) and is particularly suited for tight or hard to reach spaces --spaces where traditional lamp fixtures would not physically fit into or where bulb maintenance would be difficult, expensive, or simply impossible to perform.

The idea of routing light (or more precisely, the routing of photons behaving in wave fashion that make up the visible portion of electromagnetic radiation ) began with the study of refraction --the changing or bending of a wave's direction when it passes from one medium to another.

Per 15th century Dutch mathematician Willebrord Snellius (among a few others before him), this bending happens up to a "critical angle". Once reached, waves no longer bend but get reflected back inward.

End emitting fiber optic cable is designed to take advantage of this fact. Light entering refracts beyond this maximum angle which keeps it moving within the cable until its end is reached.

Side emitting fiber optic cable, a cable that glows similar to NEON gas tubes, also operates on this same principal. The difference being that this type of cable allows a portion of light to be "spilled" outward along the way to its end.

Because nearly nothing in the physical world is 100% efficient, the practical result of routing light through fiber strands is brightness exiting a cable is primarily dependent on total length. Typically good quality PMMA acrylic material cables will transmit a high percentage of the incoming light to over 50ft in distance --side emitting cable over 100ft when using light sources "pumping" from both ends.

At a high level, lighting via fiber has the following attributes:

• Lighting a target requires simply routing a flexible fiber cable with focusing lens at its end (50-100ft max)
• Application of light can be directional to a target or emitting to its side for full length of cable
• Fiber cable is virtually unbreakable and highly durable (20+ years)
• A single source lamp coupled to separate fiber cables can light many targets at once
• Fiber systems are energy efficient since a single light source (also efficient in of itself) can illuminate many targets at once
• Color changing light is easily done by the addition of a color filter at source

For more on fiber optic system versatility, technical highlights, and basic physics of total internal reflection which makes "piping light" at all possible, see below.

Fiber optic lighting's illumination source is very often a single high brightness energy efficient lamp. The source of choice has been to date a 150-400 watt ceramic metal halide (CMH) high intensity discharge (HID) lamp.

The CMH, a newer type of HID technology, has been perfected to a point that it produces between 90-117 lumens per watt
--i.e. measurement of total amount of visible light per watt of total electrical power consumed.

At this efficacy level, it is more than 80% better than a traditional incandescent bulb. This makes CMH lamps one of the most efficient light sources available today. And because the intense light they produce, (for now) they are the most suited to the task of light generation for fiber applications.