Just wondering 
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The binoculars have a prism which bends and reflects the light into the lens and also flips the image.
Most modern binoculars employ Keplerian optics whereby the image created by the objective lens (the larger lens) is viewed through a second, smaller lens (the ocular lens). Although this design allows for a high degree of magnification, it has the draw back of inverting the image. Thus, a prism is incorporated into the design of the binoculars as to correct this inversion, allowing you to see objects in the proper orientation (instead of being rotated 180 degrees). Early binoculars made us of a Porro prism to correct the inversion. This design uses a Z-shaped double prism and offset objective and ocular lenses. This prism, however, causes binoculars to be rather large to accommodate for the offset lenses. More modern binoculars therefore employ a roof prism, which permits binoculars to be much smaller and more compact. Roof prisms, however, let in less light than Porro prisms and also cost more to construct.
Hope this helps!