Manufacturing High-Precision Optics with Xolography

1. Introduction

Xolography is a volumetric fabrication method that produces true 3D optical components in liquid resin using intersecting light beams. Unlike traditional optics manufacturing, which relies on grinding blanks or requires molds, Xolography creates finished optical elements directly from digital design. This eliminates tooling, reduces setup time, and enables geometries that are impractical or impossible with conventional methods.

2. Process Overview

Resin Setup – A transparent cuvette is filled with xoloClear, a proprietary photopolymer with dual-color photoinitiators.

Light Exposure – A thin light sheet passes through the resin while a second beam projects cross-sectional patterns at right angles.

Voxel Polymerization – Polymerization occurs only where the two beams overlap, curing solid voxels directly in 3D space.

Volumetric Build – As the sheet scans through the resin and patterns update, the full 3D optic emerges.

Post-Processing (Optional) – The part is rinsed; for specific applications, diamond turning, polishing, or coatings can be applied.

3. Advantages

• Optical-grade finish: Surface roughness ≤10 nm Ra without optical post-processing.
• Geometric freedom: Supports freeforms, enclosed cavities, and whole optical assemblies in a single build.
• Speed: Parts are fabricated in minutes; design-to-part cycles are dramatically shortened.
• No tooling: Eliminates molds, blanks, and setup steps common in grinding and injection molding.
• Integration potential: Enables overmolding or direct integration of sensors, fibers, and other components into optical structures.

4. Limitations

• Material range: Currently limited to xoloClear; other formulations (higher refractive index, UV-stable, long-term durable) are in research.
• Part size: Today's reliable range is ~5–50 mm in diameter; larger optics require hybrid strategies.
• Thermal & mechanical limits: Polymers lack the stiffness, heat resistance, and lifetime of glass optics.
• Scaling: While fast, industrial scaling and process qualification are still less mature compared to grinding and molding.

5. Materials & Specs

xoloClear

• Resolution: 5 µm
• Minimum Feature Size: 10 µm
• Surface Roughness (Ra): ≤10 nm
• Transparency: 97% over 3 mm in visible spectrum
• Long-Wavelength Cut-off: λ < 1700 nm (50%)
• Refractive Index (nd): 1.51
• Abbe Number (Vd): 62
• Lens Aperture Range: Ø 5–50 mm

Material Properties:

• Optical-grade finish and high visible light transmission
• Can be refined further by diamond turning, polishing, and coatings

Further Non-Optical Materials:

• Nanoparticle-filled resins for extended performance
• Hydrogels for biocompatible and tunable optical structures
• Elastomers for flexible or adaptive optical elements

Research Stage:

• Higher refractive index polymers (n ≈ 1.6–1.7)
• Long-term stable, UV-resistant polymers

6. Opdo's Role

At Opdo, Xolography is our standard lane for Rapid Volumetric Fabrication. We deliver:

• Fast-turn manufacturing: optical elements fabricated and shipped quickly.
• Application scaling: working with partners to develop scalable use cases for freeform and integrated optics.
• Hybrid workflows: combining Xolography with polishing, coating, and other finishing steps where required.
• Reshoring optics: building domestic manufacturing capability for mission-critical optical systems.