Choosing the correct resolution for laser engraving

Choosing the right resolution has a huge impact on the final laser engraving result. Other important factors include the material being processed, the chosen graphic and the processing time.

Material and graphics

Laser engraving result at 333 dpi — Laser engraving result at 250 dpi

Laser engraving result at 250 dpi — Laser engraving result at 333 dpi

The correct resolution for laser engraving — Laser engraving result at 1000 dpi

Material impact

Materials absorb energy during laser engraving. Due to the strong heating, the dots become larger and can overlap (= “dot bleed”). This is an important property for photo engraving. In order to counter this effect, the right resolution is crucial.

Material	Preferred resolutions
wood, glass, textile, stone	lower resolutions: 125, 250 and 333 dpi
acrylic, TroLase materials, paper, cardboard	moderate resolutions: von 500 to 600 dpi
stamps, metal, processing with fiber laser	higher resolutions: von 600 to 1000 dpi

Graphic

The level of detail in the graphic determines the resolution. It is recommended to increase the resolution to 600 dpi despite the “dot bleed” described above. This allows even very fine details to be optimally engraved.

Laser engraving with different resolutions

The time factor

Higher resolutions increase the time that is needed for laser engraving.
To reduce engraving time a different resolution can be selected. Using large-scale laser engravings as the example, choose a lower resolution and compensate for the resulting line spacing with a higher Z offset value.

Consistent laser engraving result - 1/4 of the original processing time

The following example shows how you can engrave the same graphic at 500dpi with the same result at 125 dpi, produced in 1/4 of the time:

Speedy 360, 80 Watt, P=65%, v=50%
Resolution	125 dpi	250 dpi	333 dpi	500 dpi
z-Offset	+12 mm	+12 mm	+9 mm	+6 mm
time [h]	1.52	3.31	4.28	6.47

Exception: Laser engraving rubber stamps:

For this application a higher resolution will increase the energy density when laser engraving. If the stamp is engraved at 500 dpi, the laser engraving speed must be reduced in order to reach the recommended engraving depth of 1.1 mm. In contrast, engraving can be faster at a resolution of 1,000 dpi and thus saving time despite the higher resolution.