Volume control of a laser-induced bubble in a capillary with an open end

Abstract

Needle-free injection device using high-speed liquid microjets is expected to solve serious problems of conventional needles such as pain and blood infection. We investigate a control method of injection volume of high-speed microjet induced by a laser pulse illuminated into a point inside a liquid in a capillary tube. The volume control of a laser-induced bubble generated by laser focusing is important to control drug’s injection volume. In this paper, we aim to predict maximum bubble volume by modifying the previous bubble volume model. For validation of revised model, we compared calculations and experimental results which obtained from images taken by a high-speed camera. As a result, it turned out that the prediction of the revised model deviate from the experimental results. This result is important in that it indicates the necessity of reconsiderations about the model assumptions and fitting parameter estimation methods.