技術情報
エンジニアリング技術情報
レーザー光源の選定の背後にある物理、トレードオフ、故障モード。設計を確定させる立場の人に向けて書いています。
選定ガイド
データシート上ではどちらも妥当に見える選択肢の間で決めること。
905 nm vs 1535 nm vs 1550 nm: choosing a wavelength for ranging and LiDAR
The wavelength decision sets your detector, your eye-safety class, your maximum usable energy and your weather performance. Here is how the three bands actually compare for ranging work.
Selection guideHow to choose a 905 nm pulsed laser diode: from range target to part number
A repeatable procedure for turning a range requirement into pulse energy, pulse energy into peak power and pulse width, and peak power into the smallest package that survives your duty cycle.
Selection guidePeak power, pulse width and duty cycle: the three numbers that define a pulsed laser diode
Peak power sells the part, pulse width sets the resolution, and duty cycle decides whether it survives. Getting the relationship wrong is the most common way a pulsed laser design fails.
Selection guideVCSEL vs edge-emitting laser: choosing a source for 3D sensing and LiDAR
Edge emitters win on peak power and range, VCSELs win on beam shape, duty cycle and cost. The comparison that matters is not watts - it is pulse energy, and the two technologies reach it in completely different ways.
受光素子
受信側。リンクマージンの大半はここで得られ、あるいは失われます。
光学
チップから目標物までビームを届けること。
Fast-axis collimation and fibre coupling: getting the beam from the die to the target
An edge emitter's 25 degree fast axis wastes most of its energy on empty sky. Here is what a fast-axis collimator actually recovers, why it is a precondition for fibre coupling, and when you should not use one.
OpticsVisible and RGB laser illumination: brightness, white balance and speckle
A visible source is not a 905 nm part with a shorter wavelength. The photopic curve decides which colour owns the power budget, etendue decides how bright the spot can be, speckle decides how uniform it looks - and the eye's aversion response changes the safety arithmetic, but less than most people assume.
安全
規格が求める内容と、それがエネルギーの目安にとって意味するもの。
物理
あらゆるレーザー測距設計を制約する関係式。
電子回路
レーザーダイオードを壊さずに駆動すること。
