Vector vs raster

Two ways of representing what the laser fires on, and why it matters in laser work.

A laser machine moves a head along a path and fires the laser as it goes. The question Beam Bench has to answer for every job is: what should the path be?

There are two fundamentally different answers, called vector and raster.

Vector

A vector is a mathematical description of a shape: "draw a line from (10, 20) to (50, 60)", "trace this Bezier curve", "go around this rectangle". The laser follows the path directly. The result is a clean line or outline cut into the material.

Vectors scale without losing quality, a circle is a circle whether it is 1 mm or 1 m. They are also fast: the head goes only where the path goes, with no extra travel.

In Beam Bench:

Line mode runs the laser along the vector path.
Fill mode scans the laser back and forth across the inside of the vector path (see Fill modes).
Offset Fill is a Fill variant that follows the path's contour rather than scanning straight lines.

Vector inputs: SVG, DXF, PDF (where the PDF has vectors), AI, EPS, and shapes you draw with the Rectangle, Ellipse, Polygon, Star, Pen, and Text tools.

Raster

A raster is a grid of pixels, each with a brightness value. To "engrave" a raster, the laser scans back and forth in horizontal lines (like a printer), firing or not firing at each pixel based on its brightness.

Raster handles tone (gradients, photos, shading) that vectors cannot. The trade-off: it is slower (every line of pixels, not just the path), and resolution is fixed (zoom in too far and you see the pixels).

In Beam Bench:

Image mode is how you engrave a raster. The image's pixels get converted to firing patterns via a dithering algorithm or as variable power (grayscale).

Raster inputs: PNG, JPG, and other common image formats.

When to use which

Some tasks are obviously vector:

Cutting parts out of material.
Engraving a logo, badge, or text.
Scoring a fold line.

Some tasks are obviously raster:

Engraving a photograph.
Reproducing a halftone illustration.
Engraving a grayscale gradient.

And some tasks blur the line:

A line drawing imported as a JPG could be vectorized first (with the Trace Image dialog) and then cut as a vector, usually a better result than rastering it.
A vector logo could be filled (vector fill) rather than engraved as a raster, usually faster and cleaner.

If you have a choice, prefer vector. It is faster and the result is sharper. Use raster when the image has tone that vectors cannot represent.

How Beam Bench handles it

The mode (Line, Fill, Image, etc.) is chosen per layer in the Cuts/Layers panel. You can mix vector and raster layers in the same project freely.