Roof Prism VS Porro Prism Binoculars

The two types of binoculars available in market today come in 2 general designs: Porro Prism Binoculars and Roof Prism Binoculars. They both use image-erecting prisms so you can see images in the correct orientation.

See the comparison of the two here:

Roof VS Porro Prism Binocular

General Information
  • Have straight tubes
  • Newer design by Zeiss and Leitz companies during the 1960s
  • Named after Italian designer Ignazio Porro
  • Standard design pre-1960s
  • Design
  • The straight tube design gives the appearance of light traveling in a straight path with complex light path
  • High-end roof prism binoculars requires more complex light pathways and are usually costly as a result
  • A classic “dog leg”, wider frame design
  • The objective lens is spaced offset from the eyepiece
  • Simpler light path with higher light efficiency
  • Advantages
  • Generally more compact
  • Easier to carry around on traveling trips or to spectator events
  • Rich depth of field & wide field of view
  • Lower cost to produce
  • Disadvantages
  • In most cases, roof prisms are much more expensive to produce
  • Requires more optical precision to manufacture
  • Comparing dollar-for-dollar, the roof prisms are more costly for the same performance as the Porro
  • Bulkier design
  • The less expensive prisms (the BK-7) may not have circular, perfect exit pupils

  • Figure 2.1 Comparison between Roof and Porro Binoculars

    Other Special Features of Binoculars

    Other Special Features of Binoculars