What is a wedge prism

What is a wedge prism

A Wedge Prism, also known as a wedge Angle prism, is an optical element with two non-parallel optical planes. Its core feature is that there is a tiny Angle between the two working planes (i.e., the wedge Angle, usually a few seconds to a few degrees), which distinguishes it from ordinary parallel plane optical Windows. Thanks to its core function of optical path deflection, it is widely used in laser calibration, optical system focusing, beam pointing adjustment and other scenarios.

1. Core Working Principle

When a beam of parallel light is perpendicularly incident on one plane of a wedge-shaped prism, the light refracts twice between the two non-parallel planes:

When the light      enters the prism medium, it deflates towards the thick end of the      prism;

When the light      exits the prism, it deflects again, and eventually the emergent light      forms a fixed deflection Angle with the incident light.

The size of the deflection Angle is determined by the wedge Angle of the prism, the refractive index of the base material, and the wavelength of the incident light. The calculation formula is:

Alpha delta material (n - 1)

Here δ is the deflection Angle, n is the refractive index of the prism material, and α is the wedge Angle.

2. Core Application Scenarios

Beam pointing    fine-tuning

When used in combination with two wedge-shaped prisms, the beam can be fine-tuned in any direction within a two-dimensional plane by rotating the relative angles of the two prisms, which is commonly used for optical path calibration in lidar and fiber optic communication systems.

Optical system    focus compensation

In imaging equipment, wedge prisms can replace the movement of part of the lens group and improve focusing accuracy by fine-tuning the optical path, suitable for high-precision microscopes, telescopes and other devices.

Beam splitting  and Angle offset

A single wedge prism can be used to produce a fixed Angle beam offset, and multiple prisms combined can achieve multi-beam splitting to meet the multi-optical path requirements of laser processing and optical inspection.

3. Key Materials and Parameters

Common base      materials

Core Performance      parameters

Wedge Angle       tolerance:       ±30 "for industrial grade, ±10" for       high precision grade, directly determines beam deflection accuracy;

Surface shape       accuracy:       λ/10 to λ/20 (λ=632.8nm),       ensuring no distortion in the optical path;

Surface quality: Compliant       with ISO 10110-7 (scratches ≤20/10, pitting ≤0.05mm);

Anti-reflection       coating option: After AR coating, the reflectance on the single       surface is ≤0.2%, enhancing the light transmission efficiency.

4. UltraOpto product advantages

UltraOpto wedge prisms support custom wedge angles and sizes, and can match the best material and coating solutions according to the band and deflection Angle requirements of the customer's optical system. The entire process uses ultra-precision processing technology to ensure stable wedge Angle accuracy and surface shape quality, providing a highly reliable optical path adjustment solution for laser calibration and imaging systems.