High-Precision Optomechanical CNC Machining for Optical Components

A CNC-machined optical part can meet every dimensional tolerance on the drawing and still create problems during assembly.

Why? Because optical performance often depends on the relationship between features — not just the accuracy of each dimension.

A small shift between a lens seat and mounting thread can affect the optical axis. A thin housing can distort after unclamping. An anodized precision fit can become too tight after finishing.

At XY-GLOBAL, we approach optomechanical machining with the final assembly in mind. The focus is on datum control, concentricity, runout, precision fits and assembly repeatability — not simply making individual dimensions pass inspection.

CNC-Machined Optomechanical Parts

We manufacture custom components such as:

• Lens barrels and lens housings

• Lens and mirror mounts

• Retaining rings and precision spacers

• Camera and sensor housings

• LiDAR housings

• Laser housings

• Optical base plates

• Filter and prism mounts

• Fine-thread adjustment components

These parts are used in automotive LiDAR, machine vision, industrial imaging, laser equipment, scientific instruments and medical optical systems.

Three Challenges That Matter in Optical Machining

1. Lens Barrel Concentricity and Runout

Problem:
Lens barrels often contain multiple bores, lens seats, shoulders and fine threads that must share the same mechanical axis.

Optical risk:
Re-clamping between operations can introduce small datum shifts. Individual dimensions may still be within tolerance while the lens seats and mounting interface become slightly misaligned.

Our approach:
Where part geometry allows, critical coaxial features are machined from a common datum and completed in as few setups as practical.

This helps reduce accumulated setup error and improves control of concentricity and runout between lens seats, bores, locating diameters and threaded interfaces.

2. Thin-Wall Housing Distortion

Problem:
LiDAR housings, camera bodies and other optical enclosures often combine large pockets with thin aluminum walls.

Material stress, cutting forces and clamping pressure can cause the part to move after machining.

Optical risk:
Distortion around sensor or mounting surfaces may change alignment, flatness or assembly position.

Our approach:
Depending on the design, we use controlled fixturing, balanced material removal, staged roughing and finishing, and intermediate inspection.

For distortion-sensitive parts, the machining sequence is planned around part stability rather than simply removing material as quickly as possible.

3. Fine Threads and Precision Fits

Problem:
Lens barrels, retaining rings and focusing mechanisms often rely on fine threads and closely controlled mating surfaces.

Optical risk:
Excessive clearance can introduce movement, while an overly tight fit can create inconsistent assembly or preload.

Our approach:
Thread fit, mating features and critical dimensions are reviewed during DFM before production.

Surface treatment is considered at the same stage because anodizing or plating can change the final dimensions of threads, bores and locating surfaces.

Tolerance Specifications & Inspection

For suitable geometries and features, critical linear dimensions can reach approximately ±0.005 mm.

This is not a general tolerance for every dimension on every part.

Actual capability depends on:

• Part geometry and size

• Material

• Wall thickness

• Turning or milling process

• Datum structure

• Feature accessibility

• Surface treatment

• Inspection method

Geometric requirements such as concentricity, runout, flatness, perpendicularity and true position should be reviewed individually against the drawing.

Inspection methods are selected according to the feature and tolerance, including precision gauges, optical measurement equipment and CMM inspection where appropriate.

Common Materials & Surface Treatments

Typical materials include:

• 6061-T6 and 7075-T6 aluminum

• Stainless steel

• Brass

• Copper

Aluminum is particularly common for lens barrels, optical housings and LiDAR components because it combines low weight with good machinability.

Typical finishes include:

• Black anodizing

• Clear anodizing

• Hard anodizing

• Chemical conversion coating

• Electroless nickel plating

• Passivation

For optical components, surface treatment is not purely cosmetic.

Black finishes may also be specified to help manage internal reflections and stray light. More importantly, coating thickness must be considered wherever threads, precision bores or mating surfaces affect final assembly.

DFM for Optomechanical Parts

A useful DFM review should identify manufacturing risks before the first parts are made.

We typically review:

• Datum structure

• Tight tolerance combinations

• Coaxial features

• Thin-wall geometry

• Fine threads

• Tool accessibility

• Surface-treatment allowance

• Inspection feasibility

For example, several lens seats and a mounting thread may be redesigned or machined around a common datum to reduce tolerance stack-up.

For a thin LiDAR housing, fixture support and material-removal sequence may be reviewed before production to reduce distortion.

For anodized precision fits, the coating specification should be considered before final machining dimensions are released.

The objective is not simply to make a part easier to machine. It is to protect the function of the final optical assembly.

Why Work With XY-GLOBAL?

Our approach is built around three priorities.

Optical assembly performance, not just drawing compliance.
We consider how lens seats, sensor surfaces, bores, threads and mounting features interact after assembly.

Consistent datum control.
Critical features are kept on common machining references wherever practical to reduce tolerance stack-up and unnecessary setup variation.

Early DFM before machining.
Tolerance relationships, thin walls, threads, precision fits and surface treatments are reviewed before production begins.

XY-GLOBAL supports CNC turning, 3-axis and 5-axis machining, precision inspection, prototypes and repeat production.

Our quality systems include ISO 9001 and ISO 13485, with ISO 13485 particularly relevant to medical-device-related optical programs.

Get a Free DFM Review

Developing a lens barrel, optical mount, LiDAR housing, camera housing or other optomechanical component?

Send us your:

• 2D drawing

• 3D model

• Material specification

• Surface-finish requirement

• Target quantity

Our engineering team can review the design for machining feasibility, datum strategy, tolerance risks, thin-wall distortion, precision fits and surface-treatment considerations.

The initial DFM review is free and carries no obligation to place an order.

FAQ

Can you hold ±0.005 mm?

On suitable critical linear features, yes. Geometric tolerances and complex features are reviewed separately according to the drawing.

How do you control lens barrel concentricity?

Where practical, coaxial features are machined from a common datum with minimal re-clamping between critical operations.

Do you need a 2D drawing?

A STEP file is useful for initial review, but a 2D drawing is recommended when tolerances, GD&T, surface finish or critical datums need to be controlled.

Can you machine prototypes?

Yes. We support prototype parts as well as repeat production.

Do you provide DFM support?

Yes. We can review datums, tolerances, thin walls, threads, precision fits, surface treatments and inspection requirements before production.