Why Home Pure Water Systems Are So Important to Your Health

Home pure water systems have become all the rage! And it's no wonder! With all of the negative press our municipal water systems have had lately, who doesn't recognize the need to filter their own tap water. Turns out bottled water is not much better than tap water, if any. In other words, having your own home pure water system is no longer an luxury. It's now a necessity.

The only question is which type of the many pure water systems available should you buy? There are a number of ways to purify and filter water. Among them are distillation, reverse osmosis, exposure to ultraviolet light, and carbon and ceramic filtration. All of these have their strengths and weaknesses.

Although distillation is a very common pure water system, it has two faults. For one thing, it's expensive. For another you have to be careful about distilling chlorinated water. (Distillers work by heating up the water. The chlorine that's already in your water can create carcinogenic compounds with organic materials, which then will be vaporized by the distiller. This means they'll end up in the supposedly pure water.)

Reverse osmosis was the water purification system of choice. There are some issues with it as well. Reverse osmosis is not nearly as expensive as distillation. So, money is not the issue. It's the fact that it "demineralizes" the water.

The water that we are supposed to drink has naturally occurring minerals in it. Although the amounts vary, in pure, natural water you'll find trace amounts of minerals like potassium, calcium, and magnesium. Our bodies need these trace minerals in order to function properly. Because of the way it works, reverse osmosis takes these minerals out. Some scientists actually think there are long term consequences to drinking demineralized water.

Ultraviolet radiation (UV) is also a very common technology used to create pure water systems. UV works great, by the way. It's only effective on living organisms--bacteria, viruses, and microorganisms. It will do nothing to get rid of the whole host of other stuff in your water like lead, pesticides, and prescription drugs.

Perhaps the best all around water filtration technology uses carbon and/or ceramic filters. Usually these are used in a two-step process where you filter out the organic contaminants first, then the inorganic impurities next. This way you can make the water pure, but leave in the trace minerals. This type of pure water system is also substantially cheaper than many of these other methods.

High Index Eyeglass Lenses

As anybody who has had to wear thick lenses can tell you, it can make you a little self-conscious and you would do anything for something a little thinner. Lenses are made from a variety of materials. Many of these materials are designed to be thinner than a conventional lens. This means that they have a higher Index of refraction. Index of Refraction refers to the lenses ability to bend light. The prescription of a lens is determined by two main factors; the lens?s index of refraction and lens curvature. The higher the index the less curvature that is needed thus the lens can be processed thinner. The lower the index the more curvature is needed for the desired prescription thus making it thicker.

Often you may hear the Optician or doctor referring to these lenses by numbers such as such as 1.60, 1.66, and 1.70. These numbers represent the refractive power of the lens. The higher the number the thinner the lens. There are several other benefits to a high index lens. Lenses with a higher index often have a greater tensile strength than other conventional materials. This tensile strength is around 15,000 psi! This makes them suitable for drill mount glasses.

But because a lens is thinner and tougher does not mean that it is without flaws. The higher the index the more reflection that occurs off of the lens surface. The higher the index the more resistance is given to light. This resistance increases the amount of light that is bounces off. For instance a conventional plastic lens with an index of 1.498 will cause 8% of the light to reflect off of the surfaces creating 92% transmission. A lens with the index of 1.70 will cause 13.6% of the light to be reflected creating only 86.4% transmission. The application of an Anti-reflective coating can greatly increase light transmission.

Chromatic Aberration

Another aspect of these lenses that wearers often find annoying is a phenomenon called Chromatic aberration. Looking through a lens with a high index you may notice that there is a color hue around certain images. The further you move from the center of the lens the more noticeable it becomes. High index lenses have a very high ability to create dispersion. When white light passes through one of these lenses it begins to break up into its component colors. This can be minimized by choosing a frame that is smaller and allows the eye to center well within it. It often takes no longer than a day or so to fully adapt.

Depending on your needs a high index lens may be ideal for you. They are cosmetically appealing and are available in many lens designs including Progressive lenses. Proper frame selection and a thin lens can drastically improve appearances.