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30 mm BK7 Risley Prism Pair / Optical Wedge Pair for Adjustable Laser Beam Steering

A compact pair of optical wedge prisms for variable beam deflection, laser alignment, optical bench experiments and educational demonstrations of Risley-prism beam steering.

EUR 40.00 (+ shipping)

Indicative shipping

European UnionEUR 12
United StatesUSD 60
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Adjustable beam deflection: by rotating the two wedge prisms relative to each other, the output beam direction can be adjusted from near-zero deviation up to the maximum combined deviation. For custom quantities, matched pairs or clarification, please contact us via email.
30 mm BK7 Risley prism / optical wedge Risley prism beam steering animation Risley prism pattern scan

Product Description

This is a pair of 30 mm BK7 optical wedge prisms, suitable for use as a Risley prism pair. When the two prisms are rotated with respect to each other, they act as a simple and robust variable beam deflector.

The main advantage of a Risley arrangement is that it can steer a laser beam without translating the optical components. Depending on the relative angular position of the two wedges, the beam deviation can be continuously varied from a nearly compensated position to the maximum combined deflection.

  • Useful for optical alignment and laser beam steering experiments
  • Suitable for optics benches, lab demonstrations and educational kits
  • Compact passive optical component; no electronics required
  • Can also be used as individual 30 mm optical wedge prisms

Technical Specifications

Product typeRisley prism pair / optical wedge pair
Diameter30 mm
MaterialBK7 optical glass
Wedge angleapprox. 5–8°
Approx. beam deviationabout 2.5–4.1° per prism, depending on wedge angle and wavelength
Maximum pair deviationabout 5–8° for similar wedges, approximate value
CoatingAR coated, unless otherwise specified
ConditionNew old stock / unused optical components

How a Risley Prism Pair Works

A single wedge prism deflects a transmitted beam by a small angle. With two wedge prisms in series, the total deviation depends on their relative rotation:

  • Opposite orientation: the deviations largely compensate each other.
  • Intermediate orientation: the beam is deflected by an adjustable amount and direction.
  • Same orientation: the deviations add, giving the maximum beam steering angle.
The deviation values are approximate and depend on wavelength, exact wedge angle and refractive index. These prisms are intended as optical components for experiments and setups, not as a calibrated scanning instrument.

Typical Applications

  • Variable laser beam steering
  • Laser alignment and beam-position correction
  • Optical bench experiments
  • Educational demonstration of refraction and vector beam deviation
  • DIY optical scanner concepts
  • Testing, prototyping and laboratory setups

The components are especially useful when a simple, compact and purely optical method is needed to change the direction of a narrow beam.