Down Conversion (IMAGE) Joint Quantum Institute Caption In parametric down conversion, an incoming photon (in this case an ultraviolet photon) is converted into two daughter photons whose energy and momenta add up to that of the incoming photon. Credit NIST Usage Restrictions None License Licensed 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.