A Wedge Prism is an optical component with a shallow angle between its input and output faces. Wedge prisms are excellent for laser beam steering applications, as the oblique side and flat side permit the wedge prism to deflect light towards the thicker portion of the prism with specific deflection angles. The larger the wedge angle, the greater the angle of deviation when light emerges from the prism. Furthermore, rotating the wedge prism about the optical axis is a great approach to obtaining circular laser beam scanning output. To make insertion into rotatable mounting more convenient, wedge prisms are often fabricated into circular shapes.

Wedge prisms could either be used as a single element or in pairs (in this case, the wedge prism pair could also be called a Risley Prism Pair). As mentioned above, a single wedge prism could be utilized to deviate a laser beam at a set angle or realize the tracing of a circular light path on the vertical plane. Wedge prisms in pairs can be used for anamorphic beam shaping (i. e. to correct the elliptical beams into circular ones in laser diodes). Besides, by spinning the two wedge prisms in conjunction at relative rotation speeds, one can attain an adjustable amount of light deflection, the exiting laser beam could be positioned in a random direction inside a cone that takes the incident beam as the center axis (i.e., laser scanning output with spontaneous beam profile are feasible). or, in other words, assume α is the light deviation from an individual wedge prism, a pair of Risley wedge prisms can steer a beam in whatever place within a circle defined as the angle 4α.

Shanghai North Optics offers Off-the-shelf Wedge Prisms made from N-BK7 with deviation angles ranging from 2° to 10°. N-BK7 is a RoHS-compliant SCHOTT flagship glass. It is a borosilicate crown glass with a low refractive index and chromatic dispersion. N-BK7 is one of the world’s most prevalent optical materials to manufacture premium optics, with its exceptional transmission between 0.35-2.0 micros, decent mechanical strength, and high chemical inertia. N-BK7 also reveals its virtues in aspects including high scratching resistance, low content of bubbles, and inclusions. North Optics sources N-BK7 from SCHOTT, and our wedge prisms made from N-BK7 exhibit reliable performance and a promising life span.

Coating options of North Optics’s wedge prisms include uncoated, or anti-reflection coatings with different bandwidths: 350-700 nm AR Coating, 650-1050 nm AR Coating, and 1050-1700 nm AR Coating. North Optics is consistent in investing in developing cutting-edge technologies aimed at fostering a strong production line. The diameters of wedge prisms are all 25.4mm, being standardized for ease of mounting. We also provide Custom Wedge Prisms, you might check the specifications by clicking the bold text.

Application Notes:

1. Wedge Prism could either be used as a single element or in pairs. Operating alone, wedge prisms could be used for beam steering, where the extent of angular deviation is often slight. ( See Figure 1. below). A single wedge prism might also be installed in a rotatable mount so that through rotating the wedge prism about the optical axis, a circle traced using the deviated beam could be formed.