Processing apparatus

A processing apparatus for processing a plate-shaped workpiece while holding a face side of the workpiece that has a plurality of devices, each device being formed in respective areas demarcated by a plurality of projected dicing lines established on the face side, the processing apparatus comprising:

• a chuck table for holding the face side of the workpiece thereon, the chuck table having a holding member including a surface and another surface positioned opposite the surface and having a predetermined region made of a transparent material extending from the surface to the other surface;
• a processing unit for processing the workpiece whose face side is being held on the chuck table, thereby forming a processed groove in the workpiece;
• a first image capturing unit disposed above the chuck table and having a first image capturing device for capturing an image of a reverse side of the workpiece held on the chuck table, wherein the workpiece defines a Z-axis direction extending between the face side of the workpiece and the reverse side of the workpiece;
• a second image capturing unit disposed below the chuck table and having a second image capturing device for capturing an image of the face side of the workpiece through the holding member;
• a display device for displaying the image of the workpiece captured by at least either the first image capturing unit or the second image capturing unit;
• and
• a controller having a storage section for storing programs for performing an image processing process and a processing device for processing the images according to the programs stored in the storage section,
• wherein the controller is configured and arranged to:
• obtain a first image group of images of the processed groove from the first image capturing unit by positioning a focal point thereof at an initial position along the Z-axis direction and relatively moving the focal point of the first image capturing unit and the workpiece with respect to each other in an X-axis direction, while maintaining the focal point of the first image capturing unit at the initial Z-axis position, to obtain an initial image of the first image group;
• then positioning the focal point of the first image capturing unit at an intermediate position along the Z-axis direction and relatively moving the focal point of the first image capturing unit and the workpiece with respect to each other in an X-axis direction, while maintaining the focal point of the first image capturing unit at the intermediate Z-axis position, to obtain an intermediate image of the first image group;
• and then positioning the focal point of the first image capturing unit at an additional position along the Z-axis direction and relatively moving the focal point of the first image capturing unit and the workpiece with respect to each other in an X-axis direction, while maintaining the focal point of the first image capturing unit at the additional Z-axis position, to obtain an additional image of the first image group, wherein each of the images of the first image group includes a piece of first image information representing a shape of the processed groove;
• obtain a second image group of images of the processed groove from the second image capturing unit by positioning a focal point thereof at an initial position along the Z-axis direction and relatively moving the focal point of the second image capturing unit and the workpiece with respect to each other in an X-axis direction, while maintaining the focal point of the second image capturing unit at the initial Z-axis position, to obtain an initial image of the second image group;
• then positioning the focal point of the second image capturing unit at an intermediate position along the Z-axis direction and relatively moving the focal point of the second image capturing unit and the workpiece with respect to each other in an X-axis direction, while maintaining the focal point of the second image capturing unit at the intermediate Z-axis position, to obtain an intermediate image of the second image group;
• and then positioning the focal point of the second image capturing unit at an additional position along the Z-axis direction and relatively moving the focal point of the second image capturing unit and the workpiece with respect to each other in an X-axis direction, while maintaining the focal point of the second image capturing unit at the additional Z-axis position, to obtain an additional image of the second image group, wherein each of the images of the second image group includes a piece of second image information representing a shape of the processed groove;
• order the pieces of at least either the first image information or the second image information into a sequence along the Z-axis direction of the workpiece, thereby generating a three-dimensional image of the processed groove;
• and
• display the three-dimensional image on the display device.