Convex Lenses and Magnification

• Whatever the material, convex lenses make things appear larger. Think of a prism: light bends towars the base, or thickest part of the prism. A magnifying lens is like two prisms put together with the bases, or thickest part, in the center.
  
  

Glass Magnifying Lenses

• Convex magnifying lenses made from glass are heavier but have the best optics. The speed of light changes through different material and the light bends a little differently through glass and plastic. Glass is favored for the clearest vision, but the lenses are heavier and break easier.
  
  

Plastic Magnifying Lenses

• Plastic or acrylic magnifying lenses work the same way as glass magnifying lenses. The optics are not quite as good but for most work, plastic magnifiers are acceptable. This type of lens works well for children or for someone who cannot hold heavy objects. Most basic magnifiers are made with plastic lenses.
  
  

Considerations

• A different type of magnifying lens is known as a magnifying sheet, which is a thin piece of material made from multiple concentric ring-shaped lenses. This type of lens is known as a Fresnel lens and is lightweight.