The spatial spectrum synthesis process in HISTR-SAPM. (image) SPIE--International Society for Optics and Photonics Share Print E-Mail Caption The spatial spectrum synthesis process in HISTR-SAPM. Credit SPIE Usage Restrictions None Share Print E-Mail 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.