Optics and Photonics Simulators

How to Use

1. Select optical element type (single lens, lens assembly, diffraction grating, or single-mode fiber) from the component library
2. Input wavelength (typically 400–700 nm for visible, or 1310/1550 nm for telecom bands), refractive indices (e.g., BK7 glass n=1.517), and geometric parameters (focal length, grating pitch, fiber core diameter)
3. Apply the cat-filter parameter to isolate spectral regions, then run simulation to compute point spread function, modulation transfer function, or mode field diameter

Worked Example

Design a two-lens imaging system using BK7 and SF5 glass. Set first lens focal length f₁ = 50 mm, second lens f₂ = 100 mm, separation d = 120 mm, wavelength λ = 546 nm (green). Apply cat-filter to bandpass 530–560 nm. Simulation outputs: combined focal length f_sys = 33.3 mm, chromatic aberration ΔZ = 0.8 μm across filter band, lateral magnification M = −2.0, diffraction-limited spot diameter = 1.4 μm at f/8 aperture. Verify MTF exceeds 0.8 at 100 lp/mm.

Practical Notes

1. For telecommunications fiber optics, set wavelength to 1550 nm ITU C-band; use cat-filter to analyze single-mode cutoff near 1260 nm—mode field diameter typically 10.4 μm for standard SMF-28
2. Diffraction grating simulations: input groove density (1200 lines/mm), order m = 1 or 2, and cat-filter spectral range to predict grating equation deviations and efficiency roll-off at edges
3. Account for material dispersion curves; refractive index changes ~0.01 per 100 nm for crown glass—cat-filter prevents extrapolation beyond manufacturer data