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LPCM & DPI: The Density Factor

Density determines how many times the laser hits the same physical area. It is a linear "additive" variable: double the density, and you double the energy dose.

Material: Stainless Steel
Hardware: 5W IR Laser (0.03mm spot)
Settings: 30% Power · 500mm/s · 200 LPCM

Visual Overlap

The Scan Gap vs. Spot Size

On the xTool F2, your IR spot size is 0.03mm, but the Blue Diode is a 0.08 x 0.06mm rectangle. The "height" of the beam determines how many lines you need to cover the surface.

Lines per cm (LPCM) 200
Scan Gap (Line Spacing)
The physical distance between the center of each laser line. Spacing < 0.03mm results in overlapping passes on the IR module.
0.0500 mm
Thermal Overlap
Calculates the spatial relationship between scan lines. Overdraw means the laser spot covers the same area multiple times. Gap means untouched raw material is visible.
0% None
Total Energy Multiplier
Density is Additive. Double the LPCM = Double the energy dose. A 2.0x multiplier means every physical point on the material is hit twice by the beam.
x1.0

* IR Spot Size: 0.03mm (30 microns)
* Theoretical "Perfect" Fill: 333 LPCM

Toolbox

Density Converter

Different software uses different units. LightBurn typically defaults to DPI (Dots Per Inch) or Interval (mm), while XCS defaults to LPCM (Lines Per Centimeter).

Interval: 0.0300 mm Gap between scan lines
DPI = LPCM × 2.54
LPCM = DPI ÷ 2.54
Interval = 10 ÷ LPCM

The Energy Connection

Why Density feels "Linear"

Unlike Speed, which is a reciprocal (1/x) curve, Density is Additive. If you change from 200 LPCM to 400 LPCM, you are delivering exactly 100% more energy to the material surface.

The "HD" Trap: Setting your F2 to 1000 LPCM doesn't make the image 3x sharper than 333 LPCM—it just makes it 3x hotter. Because the spot size is 0.03mm, any gap smaller than that simply blurs the lines together into a single "plowed" field of heat.
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