摘要：A double-layer harmonic diffractive element （hde） structure is investigated and the optimization procedure is given based on the equation of diffraction efficiency of the double-layer diffractive optical element. A new infrared double-layer inverted telephoto-optical system with an hde is designed, which can work in the mid- and farinfrared wavebands. The diffraction efficiency of the system at each wavelength in the designed two wavebands is larger than 90%, which improves the image contrast and the imaging quality significantly.

摘要：深入研究了双层谐衍射光学元件,基于衍射效率方程对双层衍射元件的衍射效率进行优化.光学系统在中波红外和长波红外波段的衍射效率均超过了99%,极大地提高了图像的对比度和像质.设计了一款新型的红外双波段衍射望远镜,取得了接近衍射极限的成像质量,易于加工.

摘要：在2005年RSNA上，GE公司展示了磁共振梯度技术的最新研发成果——绿色环保梯度系统，并发布了全球首款配备绿色环保梯度系统的磁共振——Signa hde 1.5T。绿色环保梯度是基于ecomagination（绿色创想）理念设计研发的最新技术，