Custom right-angle, penta, dove, rhomboid, roof, wedge, and compound prisms for laser, imaging, and metrology systems.
IRD manufactures to your print. Send the drawing with the deviation the assembly needs, the controlling angles and their tolerances, the coated faces, and the acceptance method, and the technical team reviews it for manufacturability before quoting. For a new design that review is free of charge.
Standard geometries and custom assemblies are manufactured to the optical function and mounting interface on the customer print.
The standard geometries, the variations built from them, and the assemblies they go into — from laser optics through imaging devices.
Right-angle prisms turn a beam 90 degrees or retroreflect it through two reflections. Roof prisms fold the same path while inverting the image along one axis in a more compact envelope.
Penta prisms hold a fixed 90-degree deviation without inverting the image, even under small mounting movement. Dove prisms rotate or invert an image as the prism turns about its long axis.
Coated pentas are also used as beamsplitters
Wedges deviate a beam at a controlled shallow angle, and two together steer it. Rhomboids displace a beam laterally without changing its direction or inverting the image.
NIST-traceable wedge certification accurate to within 5 arc seconds
Challenging variations, cemented assemblies, and entirely new prism forms developed for applications that no standard geometry covers.
An arc second is roughly a millimetre seen from two hundred metres away. Nothing about that survives a process that was designed for dimensions and then asked to hold angles. These are the controls IRD holds across a production run.
IRD's inspection floor runs a Nikon autocollimator alongside toolmaker's scopes and interferometers. Blocking sets the angle; autocollimation is what proves it held after polishing, and it is where a drifting fixture shows up before the batch finishes.
IRD inspects to MIL-PRF-13830B and ISO 10110. The dig number is measurable — the diameter of the largest surface dig in hundredths of a millimetre — but the scratch number is a visual brightness comparison and varies with the inspector. Naming the standard on the print is what makes the acceptance repeatable.
Over-specifying scratch-dig raises cost without changing function on most facesIRD certifies custom optical wedges, from precision NIST-certifiable references through custom lighting wedges, accurate to within 5 arc seconds for the optical angle or angle of deviation.
Coatings are applied to prism faces and to the circumference, and IRD works in solder-compatible as well as dielectric and metallic stacks. Deciding that before polishing is what determines masking, fixture contact, and edge handling.
Specify each attribute to what the assembly needs. Angle, flatness, roughness, and dimensional tolerance drive different process and inspection time.
| Attribute | Typical | Best case | Application note |
|---|---|---|---|
| Angle tolerance | 5 arc min | 3 arc sec | Beam steering and interferometric alignment |
| Surface flatness | 1 wave | < 1/20 wave | Wavefront-critical faces and mirrors |
| Parallelism | 30 arc sec | < 5 arc sec | Windows, filters, and beam-steering optics |
| Surface roughness | Ra < 1 µin | Ra < 5 Å | High-energy and scatter-sensitive applications |
| Dimensional tolerance | ±.005″ | ±.0001″ | Mounting features and interfaces |
These are IRD's published process capability figures across materials and geometries, not a guarantee for a given print. Material, geometry, clear aperture, and inspection method all move them, and every angle and every surface is quoted individually. The published flatness value does not state a reference wavelength — send your operating and measurement conditions and the team will confirm against those.
A dedicated cell carries the prism from substrate through final autocollimator and interferometer checks. Geometry, coating, schedule, and traceability stay tied together, and your capacity is assigned rather than shared.
The IRD AdvantageUse these lists to frame the first review. The drawing, environment, performance requirement, inspection method, and volume determine the final route.
A web page is hard to attach to a review packet. These are IRD's own published technical documents on the questions this page raises.
How MIL-PRF-13830B scratch and dig numbers are actually assigned and counted, where ISO 10110 differs, and why over-specifying surface quality moves cost without moving function.
ArticleTechnical articleThe instruments behind an acceptance number — optical profilers, the two classes of white-light interferometer, and what each one actually measures on a finished surface.
ArticleWebinarIRD's applications team on the information that makes a quote accurate the first time, and the omissions that cause a requote.
RecordingThe finished component often crosses product categories. These pages cover the nearest materials, processes, and program contexts.
Send the drawing with the deviation or image orientation the assembly needs, the controlling angles and their tolerances, surface figure and scratch-dig per face, coated faces including the circumference, material, annual volume, and the inspection standard you will accept against. For a new design, the technical team runs a no-cost Design for Manufacturability review before quoting.
Or call 320.693.7217. If you need a NIST-traceable wedge certificate with the part, say so at the RFQ — it changes the inspection route.