US Patent 12005237 Medicament delivery device comprising a visual indicator

A pharmaceutical delivery device includes a cartridge containing a fluid. The cartridge includes a light pipe section having an input location and a light diffusing section optically coupled to the light pipe. A light source is optically coupled to the cartridge at the input location to the light pipe, such that at least some light from the light source entering at the input location is diffused at the light diffusing section.