Laser Fundamentals on 乘物游心录 · Technical Notes

Galvanometer Laser Scanners: From Core Principles to Advanced Control

Mon, 11 Aug 2025 07:25:00 +0800

A galvanometer scanner is more than a pair of moving mirrors. It is a tightly coupled mechanical, optical, sensing, and control system that turns digital trajectories into high-speed, high-precision beam motion.

Beam steering Closed-loop servo Distortion correction Scanner–stage coordination

This article closes the original Laser Fundamentals series. The next articles move from laser-system fundamentals into laser applications.

Laser Processing Parameters: Beyond Power and Wavelength

Fri, 01 Aug 2025 07:25:00 +0800

Power and wavelength are only the starting point. Processing accuracy, productivity, and quality are ultimately determined by the complete physical expression of energy: its spatial profile, temporal sequence, and vector direction.

Spatial distribution Temporal sequence Beam quality Polarization direction

Introduction

Power and wavelength are the two parameters most often mentioned in laser processing. They are necessary, but they are not sufficient. Micrometer-scale cutting, dissimilar-metal welding, and nanoscale surface texturing all require a deeper parameter set.

The Three Core Elements of a Laser: Gain Medium, Pump Source, and Resonator

Wed, 02 Jul 2025 07:45:00 +0800

Every laser depends on three core elements: a gain medium, a pump source, and an optical resonator. Their coordinated behavior turns disordered input energy into a directional, coherent laser beam.

Stimulated emission Population inversion Energy injection Mode selection

Application background

From an engineering perspective, a laser is a precision electro-optical energy-conversion device. Its central task is to transform disordered pump energy, through a specific physical mechanism, into coherent electromagnetic radiation whose direction, frequency, and phase are highly organized.

Laser–Matter Interaction: Energy Absorption

Thu, 12 Jun 2025 07:15:00 +0800

This article opens the Laser Fundamentals series with the first event in every laser process: how matter absorbs optical energy. Later articles connect this foundation to laser sources, processing parameters, beam delivery, and manufacturing applications.

Optical properties Electronic absorption Plasma Energy relaxation

Introduction

Laser absorption is the starting point of every subsequent laser–matter interaction. How a material accepts optical energy determines whether the next response is heating, melting, vaporization, ablation, or a more complex physical or chemical transformation. Understanding this initial energy-coupling process is therefore essential for optimizing a process and diagnosing failures.