Multi-Color Fiber Light Sources: Filter-Wheel Illumination for Flexible Inspection A practical guide to using filter-wheel fiber illumination when one inspection station must evaluate several colors, coatings, printed marks, or material responses without rebuilding the optical path. Why color switching matters in machine vision Many inspection projects start by comparing which wavelength separates a defect from its background. A filter-wheel fiber source lets engineers change spectral bands while preserving camera, lens, working distance, and light geometry. How a filter-wheel fiber source works The light engine sends broadband output through a selectable filter wheel before coupling into a fiber. This keeps the output position stable while the wavelength changes. Where this approach fits best Printed mark and OCR inspection; coating and film inspection; plastic and electronic parts; laboratory validation. Selection notes for production use Evaluate contrast with fixed camera settings, confirm optical power at the selected band, and decide whether production needs wavelength switching or a fixed optimized color. LuxMV engineering recommendation Use multi-color fiber illumination for controlled wavelength screening, then translate the result into a production lighting setup with enough contrast margin for automated inspection.