OPCA chip test system (IMAGE) Optica Caption The photo shows light being focused through the microlens array onto the micro-ring in the OPCA chip test system. Credit Wei Wu, Tsinghua 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.