Linear variable filters for hyperspectral imaging applications
LASER COMPONENTS offers linear variable filters, whereby either the centre wavelength of a bandpass, or long/short pass edge increases along the length of a part. Each wavelength is a function of position on the substrate.
Spectral gradients of up to 80nm per mm can be produced using hard oxide coatings, which have good environmental stability and are well suited to both indoor and outdoor use.
For hyperspectral imaging applications, a linear variable filter is typically placed directly over a sensor array or camera to provide spectral separation along an axis. Coupled with the motion provided by either a drone or conveyer belt in the other axis, a ‘hypercube’ of x, y, z data can be produced.
The linear variable filters from LASER COMPONENTS are a precision solution for hyperspectral imaging, with full blocking of the out of band spectral range, high transmission in the wavelengths of interest, and exceptional linearity across the filter.