IPL FIlters don't do what most people think.
Understanding IPL Filters Why “that little piece of glass” matters more than most people realise If you’ve spent any time around IPL, you’ve probably heard someone say something like:“Just chuck the 640 filter in and you’re only treating 640nm.” It sounds tidy. It’s also not how IPL filters work, and that misunderstanding is one of the easiest ways to end up with inconsistent results, unnecessary inflammation, or straight-up avoidable burns. Let’s clear it up properly. The two biggest myths about IPL filters Myth 1: “The filter only lets through the wavelength written on it” When people see a filter marked 520, 590, 640, they often assume that number is the only wavelength coming out. In reality, with the common cut-off filters used in IPL, that number is usually telling you the lowest wavelength allowed through, not the only wavelength. So a “590” cut-off filter typically means:it blocks wavelengths below ~590nm and allows a broad band above it to pass (up to whatever the system’s la...