摘要 |
Lens measuring method and apparatus for obtaining a desired measurement of a lens which is electrically conductive. The lens measuring apparatus comprises a first and second electrical conducting contacts adapted to contact a portion of the surface of the lens, the relative positioning of the first and second contacts being indicative of the desired measurement of the lens. Moving means are provided for moving the first electrical conducting contact relative to the second electrically conducting contact to vary the relative positioning of the first and second contacts. The apparatus also includes means for applying a potential across the first and second contacts to cause a current to be conducted between the first and second contacts through the lens when both the first and second contacts contact the surface of the lens, and sensing means are provided for sensing such current to indicate that both contacts are in contact with the lens. In the lens measuring method, the movement of the first contact is stopped when current between the two contacts is detected so that the precise relative position of the first and second contacts can be determined at the instant the first and second contacts contact the surface of the lens.
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