Opticals

The lens system is the most important aspect of the optics in a projector. The primary task of the lens is to focus the light emitted from the source and direct it toward the projection surface. There are typically two types of lenses used in DIY projectors:

  • Converging Lens: These lenses focus the light rays into a single point. When used correctly, they help project a sharp image on the screen. A common choice for a DIY projector is a magnifying lens, which is easy to find and affordable. The size of the lens will also affect the image quality and projection size.

  • Fresnel Lenses: A type of lens that helps to focus light, but it’s made from a series of concentric rings. Fresnel lenses are thinner than traditional lenses and can help save space in a DIY projector setup. They also have a wide field of view, which is useful when projecting images over large areas.

  • Focal Length: The focal length of the lens plays a crucial role in determining the size and focus of the projected image. The longer the focal length, the larger the image will be, but it also requires a larger distance between the lens and the screen.