DLP: DLP is a resin 3D printing process that cures a whole layer at once by projecting an image of it onto liquid resin with a digital light projector.
DLP uses a projector built around a chip of tiny mirrors to flash the full cross-section of a layer onto a vat of photopolymer resin. Because the whole layer cures in one exposure, the time per layer barely changes with how much of the platform is filled. Detail in the plane is set by the projector’s pixel size, so the same projector spread over a larger build area gives coarser pixels.
What it means for the price
With layer time roughly fixed, the build time of a DLP job is driven by the height of the tallest part on the platform and the layer height. That makes it efficient to fill a platform: each extra part adds resin, supports and finishing labour, but little machine time. Orientation is a trade. Laying a part flat cuts the number of layers but raises the area each layer must peel from the vat and often needs more supports.
Example: a platform of dental models 25 mm tall printed at 0.05 mm layers is 500 layers whether one model or twenty sits on it. The figures are an example.
Common confusions
DLP and MSLA both cure whole layers at once; the difference is the light source, a projector against an LCD mask. Laser SLA traces each layer instead. Quotometry prices DLP today with the other resin processes; see the resin process page.
Go deeper: Resin printing cost: how to price SLA, DLP and MSLA prints