Fig. 6From: Separation of microalgae from bacterial contaminants using spiral microchannel in the presence of a chemoattractantA The defocused method of the CO2 laser machine with a 3 mm defocusing distance away from the material forms microchannels. B The focused method of the CO2 laser machine with direct focusing of the laser beam onto the acrylic material forms a Gaussian shape cross-sectionBack to article page