The glass chip is a microfluidic device designed for the generation of monodisperse water-in-oil (W/O) droplets and emulsions. Compared to conventional droplet generator chips, the flow focusing geometry enables faster droplet formation and improved size uniformity. By precisely adjusting the flow rates of the continuous (oil) phase and dispersed (aqueous) phase, as well as the interfacial tension, droplets of controlled sizes can be consistently produced within the microchannels.