In 2025–2026, the broader class of layerless resin printing technologies has expanded beyond CAL to include xolography, multi-beam volumetric printing, and acoustic-assisted curing: all eliminating layer-by-layer construction entirely.
Layerless Technologies
1. CAL (Computed Axial Lithography)
Rotational projection from multiple angles. Speed: 30–120 seconds.
2. Xolography
Developed by xolo GmbH: uses two photoinitiators with different absorption spectra. Polymerization occurs only where both beams intersect. Resolution: 25–50 μm.
3. Multi-Beam Volumetric
Multiple laser beams intersect at a focus point inside the resin. Curing occurs only at the focal point.
4. Acoustic-Assisted
Ultrasonic waves focus acoustic energy to trigger localized curing. Early research phase.
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Technology Comparison
| Technology | Resolution | Speed | Volume | TRL |
|---|---|---|---|---|
| CAL | 50–100 μm | 30–120 s | Ø100 mm | 6–7 |
| Xolography | 25–50 μm | 10–60 s | 50×50×50 mm | 5–6 |
| Multi-Beam | 10–50 μm | Minutes | < 30 mm | 3–4 |
| Acoustic | 100–500 μm | Minutes | Variable | 2–3 |
Pros and Cons
Pros:
- Layer-Less: Isotropic properties, no staircase artifacts.
- Extreme Speed: Parts in seconds instead of hours.
- No Supports: Liquid resin supports the object.
Cons:
- Early Stage: Most technologies at TRL 3–6.
- Limited Volume: Maximum ~100 mm.
- Special Resins: Requires photoinitiators with nonlinear response.
FAQ
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The full picture
This article is one page from The Big Book of 3D Printing: 704 illustrated pages covering every technology, material and fix in one reference.
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Updated on 11 September 2026
This article was written with AI assistance; the facts were checked against the sources on 11 September 2026.