This prism is a dispersion prism with deflection by 90°. It can be regarded as a combination of two 30° prisms with a 90° reflection prism. The effect of the combination of the two 30° prisms equals a 60° dispersion prism and the 90° prism acts only as a reflector without dispersion.

By rotating the prism around the axis the wavelength experiencing 90° deflection can be selected without changing the beam position. This makes Pellin-Broca prism particularly versatile, e.g. for wavelength selection in laser resonators.

We offer prisms made from optical glasses SF10 or F2 as well as from fused silica. The prisms are delivered unmounted and without antireflection coating.

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