In fact, copyrights only protect actual works in their unique form; they do not protect the ideas behind the work. What you need is patent protection. Patents available to you will vary, based on the type of invention you have and the length of time your invention will be covered. For example, two main patents--plant patents and utility patents--protect your invention for 17 years, at which point they become open for use or reproduction in the public domain. (Actually, an act of Congress can extend a plant patent, but such acts are rare.) Design patents--the most common type--range in protection length from three to 14 years (generally three, seven or 14 years).
Any person who "invents or discovers any new and usable process, machine manufacture or composition of matter, or any new and useful improvements thereof, may obtain a patent." Your specific type of patent will depend on your invention.
Excerpted from Starting a Home-based Business