| 摘要 |
A reader for semiconductor wafers includes a camera for reading a mark on a semiconductor wafer. The wafer is positioned adjacent a surface of the housing including a reading window and an illumination device. The illumination device provides both bright and dark field illumination to the wafer, and light reflected from the wafer is directed to a mirror inside the housing, which directs the light along a camera axis to a lens of the camera. The alignment of the reflected illumination can be adjusted by changing the angle of the single mirror within the reader, thereby limiting the complexity of the device. The illumination device can be an array of light emitting diodes arranged in rows. The rows are separated by baffles which restrict dispersion of light from the light emitting diodes to provide directed bright field illumination.
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