I love thinking about investment themes or trends in the economy that can help investors profit. No matter what the stock market is doing, there is always an industry or group of companies that is doing well.

One of the best investment themes going for the next decade is the eyecare industry. If you wear glasses or contacts, you already know how much this stuff costs!

According to industry research, approximately 60% of America's population requires some form of vision correction right now. The exciting part from the investor's point of view is that, in the long term, virtually everyone will require some kind of vision care product or treatment. It makes perfect sense -- demographics, longer life spans, and better technology make eye care a virtual certainty for the majority of the population at some point in time.

The best part of this reality is that you've got all sorts of investment options available to you if you want to participate in this investment theme.

About 20% of people requiring prescription glasses wear soft contact lenses. These lenses have to be replaced on a regular basis. Two growing companies selling direct to consumers in this sector are 1-800 Contacts Inc. and Coastal Contacts Inc. Both of these companies use a direct business model based on telephone and Internet orders, letting consumers bypass traditional retailers altogether.

One company that is doing very well in the eyecare industry is LCA-Vision Inc. This company offers laser eye surgery under the "LasikPlus" brand. Laser eye surgery eliminates the need for people to have to wear corrective eye glasses. People going into military or police work often have this procedure done, as well those who just don't want the burden of wearing eye glasses or contacts. This company is firing on all cylinders, gaining market share on its competitors and expanding into new markets.

Clearly, the eyecare investment theme has significant staying power over the next decade. It is an industry similar to the pet care industry, with loyal consumers and solid growth prospects. It is an industry that is almost recession proof.