Structured liquid crystal (IMAGE) Optica Caption Researchers developed a bifocal lens based on two layers of liquid crystal (LC) structures. The intensities for the two focal lengths can be easily adjusted by applying external voltage. Credit Fan Fan, Hunan University Usage Restrictions None License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.