SPOT AND LINEAR FRESNEL LENSES Both types of lenses can be used for solar cooking and boiling water.
	There are three types of Fresnel lenses, linear, spot, and continuous linear. Linear and spot lenses look similar in terms of the circular Fresnel pattern but a spot lens may appear more transparent. Spot lenses produce a very small tight focal pattern at the optimal focal length and are generally more powerful size for size. Linear lenses produce a longer flat focal pattern ranging from 1 inch high by 3 inches wide up to 8 inches wide. Continuous linear lenses are rarely used for solar and produce a thin flat beam the length of the lens much like a parabolic trough. Optically stable UV inhibitors are required for lenses experiencing solar exposure to the sun or the materials will deteriorate rapidly with sun exposure. Linear Fresnel Lens Advantages: • Less chance of damaging equipment if liquid evaporates • Long beam can be spread the length of a pipe • Powers a Steam Engine slower but more safely Disadvantages: • More opaque due to physical nature, less light (power) transferred to project • Cannot be used for melting metals • Beam NOT continuous Linear like a trough (1" tall x 3" - 6" wide optimal) Spot Fresnel Lens Advantages: • High power heat transfer (available in Crystal Clear Acrylic perfection cutting) • Can be set to less of a focal length (ideal for cooking) • Melts copper and many other materials • Powers a Sterling Engine and Steam Engine Disadvantages: • Instant flame and work hazard • Equipment damage • Does not spread over a pipe surface evenly BUY A HUGE FRESNEL LENS				LINEAR FRESNEL LENS SPOT FRESNEL LENS