In this letter, a focal tunable liquid lens using a large deformable polydimethylsiloxane (PDMS) membrane is integrated with an electromagnetic microactuator for uniform pressure on the membrane by a fabrication process of PDMS compatible with conventional micromachining processes. The fabricated device is characterized by surface profiling and optical observations. A rectangular PDMS membrane of 3 mm in width for actuation shows that the maximum displacement is 51.4 mu m when the current is 30 mA. In the optical observations, the image is blurred when the applied current is varied. From the result, it was found that the device changes the focal length. (c) 2007 American Institute of Physics.