Using a Linear Variable Bandpass Filter as a Visual Spectrometer
See how DELTA's Linear Variable Bandpass Filter is used as a Visual Spectrometer. The LVVISBP is placed on a diffusor screen that is illuminated by a controllable 3-color LED. Observe how the discrete bands of the LEDs show up and change while the mixed color cycles through the visible wavelength range.
Now, imagine you put the LVVISBP in front of a line scan array and you have a very compact mini-spectrometer without any grating and much higher light efficiency!