Volumetric Printing: the End of Layers?

What volumetric printing is

Every 3D printing process you know builds objects in layers — one line of material at a time, each layer on the one before. Volumetric printing abandons that logic entirely: the part forms all at once, inside a volume of resin.

The leading technique is called Computed Axial Lithography (CAL), and it works like a CT scan in reverse. Instead of reconstructing an object from images taken at many angles, it projects light patterns from many angles into a rotating vial of resin. Where the projections overlap enough, the resin reaches the required light dose and solidifies. Where they do not, it stays liquid.

The result is a finished part in seconds to a few minutes, regardless of how complex the geometry is.

Why this matters

Three limitations of layer-by-layer printing disappear at once:

• No layer lines. Surface finish no longer depends on layer height, because there are no layers. The stair-stepping on curved surfaces is gone.
• No anisotropy. In an FDM part, Z strength is always lower than XY strength because layers are bonded to each other. Curing everything simultaneously makes the part mechanically homogeneous in every direction.
• No supports. The part is suspended in liquid resin throughout. Nothing needs propping up, there are no removal marks, and the associated post-processing disappears.

The second point matters most for technical parts. We wrote an entire article on anisotropy in FDM precisely because it is the constraint that most shapes the design of functional parts. Volumetric printing removes it by construction.

Where the technology stands today

The concept appeared in 2017, and CAL was demonstrated in 2019 by teams at UC Berkeley and Lawrence Livermore National Laboratory. For six years it stayed confined to research labs, mainly because it required complex and expensive optical setups.

That changed in August 2026 with OpenCAL, an open project that reduces the system to accessible parts: a Raspberry Pi, an LCD, a projector and a rotation mechanism. It is the first time the technology has left the exclusive domain of research.

Even so, to be precise: CAL is in transition between research and industrial pilots. It still lacks repeatability validation, resin formulations with mechanical properties comparable to technical thermoplastics, and build volume scale.

What this means for your parts now

Little, honestly — and that is worth saying plainly rather than selling the future.

• It is resin, not thermoplastic. If your part needs PA12, PC or PEEK, volumetric printing has no equivalent today. Photopolymer resins remain more brittle and less heat resistant.
• Small volumes. Current systems work at centimetre scale. An enclosure, a bracket or a normally sized replacement part is out of reach.
• No industrial chain. There are no mature commercial machines, no certified materials, and no suppliers with production capacity.

For functional prototypes, short runs and technical parts, FDM remains the correct choice — and will remain so for several years.

Where volumetric will win first

The likeliest applications are not the ones competing with FDM. They are the ones where layer-by-layer printing fails by nature: very delicate or fragile structures that deform with platform movement; biological geometries and microfluidics; high-viscosity materials that cannot be extruded or spread.

Worth following. Not worth delaying a project for.