Reference & ToolsModule 7.2~4 min read

Glossary & Quick Reference

Every piece of jargon used in this course, alphabetical, with the shortest definition that's still accurate.

Ablation: laser-driven removal of material via vaporization. Different from melting (heat-driven) or annealing (chemistry-driven).
Anneal / Annealing: a chemical color change on metal surface caused by laser heating. No material removed; only oxide layer grown.
Air assist: pressurized air directed at the kerf to clear smoke, debris, and slag during a cut.
Anodized: aluminum surface treated with electrolytic oxide layer that holds dye. Lasers ablate the dye to reveal white aluminum oxide.

BCG: Bolt Carrier Group (firearms). 8620 case-hardened steel, surface-mark only.
BJJCZ / JCZ: galvo controller board found in OMTech and most fiber lasers. Lightburn talks to it via the Galvo edition.
Bi-directional scan: fill engraves both directions of travel. Faster than uni-directional.
Bounding box: smallest rectangle containing all graphics. Default frame mode.

CerMark / TherMark: marking sprays (LMM-14 is the aerosol for metal). Bond a black mark to bare metal under laser heat.
Cleanup pass: fast, low-power scan run between engrave passes to remove vaporized debris before it re-deposits.
Cross-hatch: fill at one angle plus a second pass at +90°. Doubles density.
Cutoff frequency: manufacturer-specified minimum frequency below which the controller derates power for source safety. Typically ~48 kHz on JPT MOPA.

Defocus: intentionally raising or lowering the head off true focus. Spreads the beam, used for black-on-stainless.
Depth map: grayscale image where pixel brightness = engrave depth. White = nearest, black = farthest.
Dither: image rendering that simulates grays via patterns of black dots (Floyd-Steinberg, Jarvis, Stucki, Atkinson, etc.).
DOF / Depth of Focus: Z range over which the beam stays effectively focused. ±0.4mm for 70mm lens, ±1.2mm for 150mm.
DPI / Dots Per Inch: engrave resolution. 318 DPI = 0.08 mm interval; 1016 DPI = 0.025 mm.

F-theta lens: flat-field galvo lens. Ensures focus stays consistent across the working area.
Fill mode: Lightburn layer mode that hatches an enclosed shape. Different from Line (vector cut/score).
Flood Fill: galvo travel-time optimization that minimizes blank-space jumps.
Focus stick: physical gauge equal to the lens's focal distance. Place on part, lower head until contact, raise by stick offset.
Frequency: pulses per second, in kHz. See Understanding Frequency.

Galvo: galvanometer-driven mirror system that steers the beam. Replaces a moving gantry. Used in fiber lasers.
Gantry: moving X/Y carriage that physically traverses the beam delivery. Used in CO2 lasers.
Grayscale (image mode): Lightburn mode that modulates Power Min ↔ Power Max per-pixel by brightness.

Hatch / Hatch interval: parallel lines that fill an area. Smaller interval = denser fill.
HRC: Rockwell C hardness scale. Tenifer Glock slides ~68 HRC; 1911 carbon steel ~40 HRC.
Hull frame: convex outline framing mode. Tighter than Bounds for irregular shapes.

Jarvis (dither): Jarvis-Judice-Ninke error-diffusion dither. Smoothest gradients; community standard for fiber photo engraving.
Job Origin (9-dot): Lightburn selector that maps the head's start position to a corner/edge/center of the design.
Jump speed: speed of mirror travel between marks (galvo). Higher = faster overall job.

Line interval: distance between hatch lines (mm). Smaller = denser fill.
Line mode: Lightburn layer mode that traces vector paths. Different from Fill (which hatches).

MOPA: Master Oscillator Power Amplifier. Fiber laser type with adjustable pulse width (2-500 ns). Enables color annealing.

OD / Optical Density: laser glasses rating. OD 5+ for 1064nm fiber; CO2 needs OD 5+ for 10600nm. Wavelengths NOT interchangeable.
Overcut: Line mode setting that extends a closed cut past its endpoint, burning through the join seam.

Pass / Loops: number of times a layer repeats. Lightburn calls it "Number of Passes"; community calls it "loops."
PMAG: Magpul polymer magazine. High-impact polymer; engraves with short pulses.
Pulse width / Q-pulse: duration of each laser pulse, in ns. MOPA-only adjustable. Default 200 ns.

Q-pulse Width: see Pulse width.
Q-switched: fiber laser type with FIXED pulse width (~80-140 ns). Cheaper than MOPA. No color annealing.

Ramp test: focus calibration: engrave a thin line on a tilted part; sharpest portion = true focus.
Relief / 3D engraving: depth-modulated engrave producing physical sculpted surface from a depth map.
Ruida: DSP controller used in many gantry-style CO2 lasers (Thunder, Boss, Aeon, Cloudray, OMTech and more).

Scan angle: direction of hatch lines in degrees. 0° = horizontal.
Shovel layer: Lightburn vector technique for multi-level coin depth. Three layers: subject + shovel (recess) + background.
Sub-layer: galvo-only Lightburn feature: up to 11 sub-tabs per layer with their own settings, run sequentially.

TC / Time Constant: galvo-only delay fields (Laser On TC, Laser Off TC, End TC, Polygon TC). Mirror settling timing in microseconds.
Tenifer: Glock's nitrided surface treatment. ~68 HRC; surface-mark only with fiber.
Threshold: image mode: pure black/white cutoff at a brightness level. Sharp edges, no grays.
Tool layer: Lightburn layer that doesn't output but is included in framing. Used for jig outlines.

Wobble: galvo-only setting that traces tiny circles along a path. Increases dwell, widens kerf, used for cutting thin metal.

Z step / Z step per pass: Lightburn Line/Image setting that drops Z height between passes. Keeps focus on the working depth during deep engraves.