Penta Prisms (PTP)

• Reflects rays through a 270° angle by two reflections, and does not invert the image
• Movement of the prism does not affect the right angle at which rays are reflected
• Dimensions : A = B = H
• Penta prisms are offered as uncoated. Coatings are available upon request.

Penta prisms are extremely useful in alignment systems as they define a right angle very precisely and independently of angle of incidence. Rays entering one face emerge from the adjacent face at precisely 90° after they have undergone two reflections inside the prism for a total of 270°. The penta prism acts as a turning mirror which is insensitive to alignment. For custom applications, anti-reflection coatings are applied to the entrance & exit surfaces. Either metallic or dielectric high reflector coatings are applied to the 2 reflective surfaces.