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The Speed Curve

Power and Density are linear fine-tuning knobs. Speed is a non-linear "turbo" knob. Understanding the $1/x$ relationship is the key to mastering high-order colors.

Material: 10x10mm Stainless Steel
Hardware: 5W IR Laser (0.03mm spot)
Settings: 30% Power (1.5W) · 500mm/s · 333 LPCM

Linear vs. Exponential

The $1/x$ Energy Spike

Power and LPC are additive—double the power, and you double the energy. But Speed sits in the denominator of the energy equation. As speed decreases, energy density doesn't just grow; it spikes.

Energy Density
Speed (mm/s)
Switch Variable
Speed (mm/s) 500
Energy Result
333 mJ/mm²
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The Candle Analogy

Think of passing your hand through a candle flame. Doubling the flame size (Power) is hot, but walking through the flame (Low Speed) is catastrophic. Speed changes the duration of the reaction.

Why the Math Differs

Power & LPCM
Linear (Additive)

Doubling power delivers exactly twice as many photons. It's like adding a second coat of paint—predictable and straight.

Speed ($mm/s$)
Non-Linear ($1/x$)

Because speed is in the denominator, a tiny change at low speeds (150 to 120) is far more aggressive than the same change at high speeds.

The Thermal Diffusion Limit

Metal acts like a heat sink. At high speeds, the laser moves faster than the heat can travel, keeping energy "trapped" at the surface for thin, vibrant colors. At low speeds, the bulk material gets hot and stops acting as a sink—surface temperature doesn't just rise; it compounds.