Luminox is a manufacturer of watches based in the United States. Their specialty is making watches that have hands and dials that glow in the dark. However, unlike normal glow in the dark illumination, these watches do not require exposure to a light source before glowing. Normally, when you buy an illuminated watch, you expect that it either needs to be charged before hand by the sun, or by a bright light. Or, there are also Indigo type watches that will glow when a button is pressed and provide a soft illumination of the face of the watch. In the case of Luminox watches, however, there doesn’t have to be any light source whatsoever, nor does it use battery power to light the dial and hands.

Instead, Luminox uses a technology involving a gas and glass capsules. These capsules are called “borosilicate glass capsules”. These are special capsules filled with a gas, which will glow with a soft light for many years. Borosilicate glass is a special blend of glass that is able to withstand considerable shock without breaking. It is made from mixing silica and boron oxide together in the glass making process, and requires different equipment to work with, since it has a higher melting point than regular glass. And, due to this mixture, it is very break resistant, to the point that when heated unevenly, it will break off in chunks rather than shatter. You probably have this type of glass in many places around your home, especially the kitchen. It is sold under the brand name “Pyrex”, which most people are familiar with. If you have any experience using Pyrex, you know that it is indeed a very strong glass, and almost unbreakable.

For Luminox watches, there is something else in use besides just the Pyrex. This is the isotope called “Tritium”. Tritium is a radioactive isotope, also called Hydrogen-3. It is basically the element Hydrogen, which is common on the Earth in the form of water, but with two extra neutrons, whereas normal hydrogen is a proton and electron. Tritium is a highly useful isotope, and has many interesting properties. It is used in light sources that do not require their own power, for example exit signs, and night sights on guns. It is also used in nuclear weapons and chemical research. It is formed in a nuclear reactor, and the production is regulated in the United States. But, Tritium itself is basically harmless, unless in direct contact with your body. Tritium is radioactive, but the radiation it gives off is not even strong enough to penetrate your skin, and certainly not the body of a watch.

The makers of Luminox watches use these two products in a combined form, called a “gaseous tritium light source”. A special tube of Pyrex is created, in long thin strands. The inside of that tube is coated with phosphors, a special chemical that will release light when excited by an energy source. These are the same phosphors that are used older televisions for example. The inside of the glass tube is coated with these phosphors, and then the tube is filled with the compressed gas of Tritium. The Tritium is the energy source needed to excite the phosphors, since, remember, Tritium is radioactive, as in it is decaying, giving off energy. The glass tubes are then cut with a special laser into whatever length is needed for the application. When it is cut by the CO2 laser, the end is fused to hold the Tritium gas on the inside. This Tritium gas continuously excites the phosphors, for many years.

A Luminox watch has small pieces of this gas filled tube molded into and part of its design. Luminox takes the small pieces of Tritium filled Pyrex tubes, and inserts them into the watch where a light source is needed. For example, the hands of the watch have pieces of glass along their length, which glow, and can be easily seen, even in complete darkness. Each of the numbers around the dial has a small piece of glass next to it that will glow, so you can tell what the hands are pointing at. In addition, many of their watches have small gas filled glass pieces where it will help illuminate a portion of the watch, for example showing 12 o’clock.

As you can tell, Luminox watches are stylish, functional, and practical. But they also combine some of the oldest technology around, the mechanics of a watch, with some of the newest technology, to make something that is truly unique. If you ever wanted to wear a piece of classic tech, nuclear tech, and great manufacturing around your wrist, you could not go wrong with a Luminox watch, which is what I think makes Luminox watches great.