#photonics

Optical-fibre photonics maths as an API, computed locally and deterministically. The numerical-aperture endpoint computes a step-index fibre's numerical aperture NA = √(n1² − n2²) from the core and cladding refractive indices, the acceptance angle θa = arcsin(NA) — the half-angle of the cone of light the fibre can capture — the full acceptance cone and the relative index difference Δ = (n1 − n2)/n1. The v-number endpoint computes the normalized frequency V = 2π·a·NA/λ from the core radius, the numerical aperture (or the indices) and the wavelength, classifies the fibre as single-mode when V is below the 2.405 cutoff or multimode above it, and gives the cutoff wavelength for single-mode operation. The modes endpoint estimates the number of guided modes — about V²/2 for a step-index fibre and V²/4 for a graded-index one — and confirms single-mode operation below the cutoff. Core radius and wavelength are in metres (1310 nm = 1.31×10⁻⁶ m) and refractive indices are dimensionless. Everything is computed locally and deterministically, so it is instant and private. Ideal for telecom, photonics, datacenter, sensor and laser app developers, fibre-link and waveguide-design tools, and optics education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is optical-fibre guiding; for thin lenses and mirrors use a lens API and for refraction at a surface a Snell API.

api.oanor.com/fiber-api

Gaussian-beam laser-optics maths as an API, computed locally and deterministically. The beam endpoint propagates a Gaussian beam from its wavelength and waist radius: the Rayleigh range z_R = π·w₀²/λ and depth of focus, the divergence half- and full-angle θ = λ/(π·w₀), and — for a given distance — the beam radius and diameter w(z) = w₀·√(1+(z/z_R)²); an optional M² beam-quality factor scales it for real beams. The focus endpoint computes the diffraction-limited focused spot of a lens, w_f = λ·f/(π·w_in), with the depth of focus and the f-number, so you can size the spot a lens will deliver. The irradiance endpoint turns a beam power and spot size into the beam area and the average and on-axis peak irradiance (power density) in W/m² and W/cm². Wavelengths are in nanometres, sizes in millimetres or micrometres, distances in metres and power in watts. Everything is computed locally and deterministically, so it is instant and private. Ideal for photonics, laser-engineering, materials-processing and optics app developers, beam-delivery and laser-safety tools, and physics education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is Gaussian-beam laser optics; for refraction use a Snell API and for thin-lens imaging a lens API.

api.oanor.com/laser-api