| 摘要 |
The detector elements are larger than an image of the spot on the array would be, but an image is not formed on the array. Instead, the beam shaping element enlarges the size of the area of illumination on the array slightly, and mixes, or homogenizes, the light. This destroys the image and the intensity variations originating at the spot on the surface that would be contained in the image. The enlargement of the area of illumination together with the homogenization allow the position of the beam on the array to be determined to a resolution of about {fraction (1/10th of the width of a detector element. This position is then converted to an absolute distance output which may be read by digital or analog means.
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