Free-space laser source in 3D: direct, or through a PM fibre
The Yanban RB-795-DFB-BFW is a free-space butterfly laser with no isolator inside. Our setup (decided 19 Oct 2026) feeds the bench through a PM fibre; the direct way is shown as the fallback. Switch between them, step through the alignment, and read the data-sheet numbers and the budgets on the right. The part shapes are the symbolic models of the equipment list, at the 100 mm beam height on a 25 mm grid; the positions are an example layout. The beam is drawn three times wider than it is; its sizes in the tables are computed from the data sheets.
Alignment, step by step
Budgets
The parts and their data-sheet values
| Part | Values | Source |
|---|
Not shown to scale: the housings of the laser mount, isolators, mirrors and FiberPorts (their real outlines are on the makers' drawings). The fibre coupling efficiency is not a data-sheet value: measure it and set the slider. The returning-light figure is our estimate from the isolator answer in section 09. Which way to go: the questions-and-answers entry on the free-space Yanban compares the two.