公开(公告)号：US20040188643A1

公开(公告)日：2004-09-30

申请号：US10396760

申请日：2003-03-24

申请人： Photon Dynamics, Inc.

发明人： Adam Weiss ,  Afsar Saranli ,  Oleksiy Lopatin ,  Alexandre Obotnine

IPC分类号： G01V008/00

CPC分类号： G01N21/95623 ,  G01N21/21 ,  G01N2021/1772 ,  G01N2021/8477 ,  G01N2201/0612 ,  G01N2201/0675

摘要： In an inspection system for planar objects having periodic structures, programmable optical Fourier filtering in the focal plane of a telecentric lens system is used to directly identify physical phenomena indicative of non-periodic defects. Lens assemblies and a coherent optical source are used to generate and observe a spatial Fourier transform of a periodic structure in the Fourier plane. Optical Fourier filtering (OFF) is performed in the focal plane using an electrically programmable and electrically alignable spatial light modulator. The spatial light modulator with high signal to noise ratio is electrically reconfigurable according to a feedback-driven, filter construction and alignment algorithm. The OFF enhances any non-periodic components present in the Fourier plane and final image plane of the object. A system having a plurality of inspection channels provides high-throughput inspection of objects with small non-periodic defects while maintaining high detection sensitivity.

摘要翻译： 在具有周期结构的平面物体的检查系统中，使用远心透镜系统的焦平面中的可编程光学傅立叶滤波来直接识别指示非周期性缺陷的物理现象。 透镜组件和相干光源用于产生和观察傅立叶平面中周期性结构的空间傅立叶变换。 光学傅立叶滤波（OFF）在焦平面上使用电可编程且电可对准的空间光调制器执行。 具有高信噪比的空间光调制器根据反馈驱动的滤波器构造和对准算法进行电可重构。 OFF增强存在于对象的傅立叶平面和最终图像平面中的任何非周期性分量。 具有多个检查通道的系统提供具有小的非周期缺陷的物体的高通量检查，同时保持高检测灵敏度。