DLP (Digital Light Processing) 3D Printing Service
Digital Light Processing (DLP) 3D printing is a high-precision additive manufacturing technology that uses projected light to cure liquid resin into solid parts. Known for speed, accuracy, and smooth surface finish, DLP is ideal for rapid prototyping, low volume production, and detailed components.
What is Digital Light Processing (DLP) 3D printing?
Digital Light Processing (DLP) is a form of additive manufacturing that uses a digital light projector to cure liquid photopolymer resin layer by layer. Unlike point-based systems, DLP exposes an entire layer using a projected image, rather than tracing geometry with a laser.
Printing an entire layer at once is what defines DLP technology. Each resin layer is cured simultaneously using a digital micromirror device (DMD), which controls how light is projected onto the resin surface. The result is a significantly faster printing speed compared to technologies that rely on a moving light source.
In manufacturing, this matters for throughput. Build times are less dependent on part complexity and more dependent on part height. This makes DLP a great choice for batch production, where multiple components can be nested and produced in just a few hours without too much impact on cycle times.
How does DLP 3D printing work?
DLP printing follows a structured, repeatable process:
- Resin preparation: Liquid resin is held in a resin tank. This photopolymer material is sensitive to UV light.
- Layer projection: A digital light projector flashes an image of the layer cross-section onto the resin surface.
- Curing process: The DLP projector exposes the print area and cures resin instantly, forming a solid resin layer. The platform then moves to allow the next thin layer of liquid resin to flow into place.
- Layer-by-layer build: This process repeats, building the part layer by layer until complete.
Post-processing workflow
Once complete, parts undergo several post-processing steps:
- Cleaning
- Excess liquid resin is removed, typically using solvent washing.
- Curing
- Additional UV light is applied to fully cure the material and achieve final mechanical properties.
- Support removal
- Temporary support structures are removed.
- Finishing
- Optional steps such as sanding, polishing, or coating improve surface quality and appearance.
These steps are essential to achieving production-ready parts with consistent performance.
DLP printing capabilities and technical specifications
DLP is a precision-led manufacturing process, but like all additive manufacturing technologies, it operates within defined constraints.
Build envelope and geometry
Typical build volumes are smaller than powder-based systems, making DLP best suited to small-to-medium components. Complex geometries are achievable, but support structures are required for overhangs and internal features.
Layer thickness and accuracy
- Layer thickness: typically 25–100 microns
- High accuracy: often within ±0.1–0.2 mm depending on geometry
- Resolution: defined by projector pixel size rather than laser spot size
This results in excellent surface finish and fine feature reproduction.
Lead times and turnaround
DLP printers offer fast turnaround, delivering parts in just a few hours to a few days. However, lead time is influenced by:
- Part height (number of layers)
- Quantity and nesting strategy
- Support requirements
- Post-processing complexity
Parts requiring extensive finishing or tight tolerances will naturally take longer.
DLP 3D printing materials (resins) and typical properties
DLP uses liquid photopolymer resins, each engineered for specific performance characteristics.
Rigid resins (ABS-like): Designed to simulate thermoplastics, these materials offer good strength and stiffness. Suitable for housings, enclosures, and functional prototypes.
Flexible and elastomeric resins: Provide rubber-like behaviour for seals, gaskets, and ergonomic components. These materials allow deformation without permanent damage.
High-temperature resins: Engineered for thermal stability, these materials can withstand elevated temperatures, making them suitable for tooling, moulds, and under-hood applications.
Biocompatible and medical-adjacent resins: Used for applications such as surgical guides, dental components, and anatomical models. Material selection is critical to meet regulatory and performance requirements.
Material choice directly impacts mechanical performance, surface finish, and post-processing requirements. For most applications, selecting the right resin is as important as the design itself - this is typically addressed during consultation.
DLP vs SLA printing
DLP and SLA (Stereolithography) are closely related, but differ in how they deliver light.
- Choose DLP printing if: You need faster batch production, consistent layer exposure, and efficient throughput for multiple parts.
- Choose SLA printing if: You require highly consistent XY resolution across larger build areas or smoother organic curves.
DLP uses a digital projector to cure entire layers using a more conventional light source (such as an arc lamp), while SLA uses a laser to trace each layer point-by-point. This makes DLP more efficient for batch production, while SLA can offer advantages for certain geometries. Also, DLP printers can achieve print speeds of up to 25 mm/hour, significantly faster than other methods.
In practice, the right choice depends on part size, geometry, and production requirements - typically assessed during project scoping.
Design guidelines (DfAM) for DLP parts
Designing for DLP reduces production risk and improves lead times.
Recommended starting points
- Minimum wall thickness: ~0.5–1.0 mm
- Minimum feature size: ~0.2–0.5 mm
- Text embossing/debossing: ≥0.3 mm depth/height
- Clearances: ~0.2–0.4 mm for moving parts
Key considerations
- Supports and orientation impact surface quality and post-processing effort
- Venting is required for hollow parts to avoid trapped resin
- Thin features may deform during curing if unsupported
When you partner with AMufacture, we can help with design optimisation, ensuring all parts are manufacturable before production begins.
Post-processing, finishing, and assembly options
Finishing options can range from as-printed surfaces to polished, coated, or painted components. These choices directly affect lead time and cost.
Parts are delivered inspection-ready or assembly-ready, depending on requirements. Secondary operations such as bonding, inserts, or machining can also be integrated.
Industry applications for DLP printing
DLP 3D printing is suitable for producing high-performance parts in various industries, including aerospace, medical, and automotive industries, where precision and surface quality are critical.
- Automotive: Interior components, prototypes, lighting housings
- Aerospace: Lightweight brackets, ducting prototypes, tooling
- Medical: Surgical guides, dental models, device housings
- Marine: Sealed components, custom fittings
- Defence: Rapid prototyping, specialised low-volume parts that require a specific mechanical property, i.e., ESD
These applications often require a balance of speed, detail, and repeatability - areas where DLP excels.
Why choose AMufacture for DLP contract manufacturing?
AMufacture delivers DLP printing as part of an integrated additive manufacturing workflow:
- Design optimisation to improve manufacturability and reduce cost
- End-to-end production from functional prototyping to low-volume production
- Traceability and quality control across all builds
- Secure digital warehouse for repeat orders and version control
- Compliance-led processes aligned to industry requirements
Projects are approached from a manufacturing perspective, ensuring parts are not only printable, but fit for purpose in real-world applications. Read more here.
DLP Printing: FAQs
Are DLP printer materials certified for industry applications? Yes – DLP's printing process, dimensional accuracy, and high-performance materials are often chosen specifically for particular resin properties. For example, medical-grade materials used in DLP printing are certified according to relevant regulatory requirements and standards.
What's the difference between DLP and LCD printing? While both use a projected light source to cure liquid resin, DLP has a faster printing speed, superior surface finish, and higher accuracy. DLP is more mature than LCD technology and is based on components that are generally more reliable and long-lasting. Also, DLP printers can manage a wider variety of materials compared to LCD printers, which are often limited in material compatibility. However, DLP technology can be more expensive than LCD 3D printers for similar performance.
What level of detail do DLP printers work to? DLP chips achieve higher contrast ratios than standard LCDs, resulting in improved image quality. DLP technology is known for its high precision and fine detail, achieving print resolutions as small as 50 microns.
