Surface inspection tool
    1.
    发明授权
    Surface inspection tool 失效
    表面检测工具

    公开(公告)号:US06624884B1

    公开(公告)日:2003-09-23

    申请号:US08840351

    申请日:1997-04-28

    IPC分类号: G01N2188

    CPC分类号: G01N21/88

    摘要: A laser based inspection tool (LIT) for inspecting planar surfaces is described. In a preferred embodiment the LIT can simultaneously inspect both planar surfaces of disks for use in disk drives. In an embodiment of the invention, light reflected from the surface at an angle slightly offset from perpendicular is routed through a telecentric lens to a detector which converts the intensity of the reflected beam into an analog signal. The analog signal is sampled and digitized to generate pixel data. A data acquisition system sequentially stores the pixel data in a buffer. A median filter and derivative analysis can be applied to the pixel data to detect deviations indicating defects. An optional calibration system periodically reflects the scanning beam back to a detector to form a reference signal for use in absolute reflectivity measurements.

    摘要翻译: 描述了一种用于检查平面的激光检测工具(LIT)。 在优选实施例中,LIT可以同时检查用于磁盘驱动器的磁盘的两个平面表面。 在本发明的一个实施例中,从表面以从垂直方向稍微偏离的角度反射的光通过远心透镜被路由到检测器,该检测器将反射光束的强度转换为模拟信号。 模拟信号被采样并数字化以产生像素数据。 数据采集​​系统将像素数据顺序存储在缓冲器中。 中值滤波器和导数分析可以应用于像素数据,以检测指示缺陷的偏差。 可选的校准系统周期性地将扫描光束反射回检测器以形成用于绝对反射率测量的参考信号。

    Surface inspection tool
    2.
    发明授权
    Surface inspection tool 失效
    表面检测工具

    公开(公告)号:US06704435B1

    公开(公告)日:2004-03-09

    申请号:US08841214

    申请日:1997-04-28

    IPC分类号: G06K900

    CPC分类号: G01N21/9506

    摘要: A laser based inspection tool (LIT) for inspecting planar surfaces is described. In a preferred embodiment the LIT can simultaneously inspect both planar surfaces of disks for use in disk drives. In one embodiment of the invention, the incident beam is directed onto the surface to be inspected at an angle slightly offset from perpendicular so that the reflected beam is physically separated from the incident beam. The reflected beam is routed to a detector which converts the intensity of the reflected into an analog signal. The analog signal is sampled and digitized to generate pixel data stored in a buffer. Various analyses are performed on the data including calculating a rate of change in the pixel data. If the rate of change in the pixel data exceeds a selected threshold that indicates a possible defect if it occurs in the data area of the disk.

    摘要翻译: 描述了一种用于检查平面的激光检测工具(LIT)。 在优选实施例中,LIT可以同时检查用于磁盘驱动器的磁盘的两个平面表面。 在本发明的一个实施例中,入射光束以与垂直稍微偏移的角度被引导到待检查的表面上,使得反射光束与入射光束物理分离。 反射光束被路由到检测器,该检测器将反射的强度转换成模拟信号。 模拟信号被采样和数字化以产生存储在缓冲器中的像素数据。 对包括计算像素数据的变化率的数据进行各种分析。 如果像素数据的变化率超过选择的阈值,如果在磁盘的数据区域中发生可能的缺陷则表示可能的缺陷。