| 摘要 |
An optical scanner module, for use in a bar code reader, has an electromagnetic coil across which is disposed a thin flexible strip. Mounted to the center of the strip is an optical element, such as a lightweight mirror, and a magnetic element, such as a permanent magnet. When an AC signal is applied to the electromagnetic coil, a varying magnetic field is produced which interacts with the fixed magnetic field of the magnet causing the magnet and mirror assembly to flex the flexible strip (e.g., in a twisting motion), thereby changing the spatial orientation of the mirror. By suitably driving the electromagnetic coil, the mirror can be made to oscillate, thereby converting a laser beam directed onto the mirror into a scanning laser beam. The entire module is compact, inexpensive to manufacture, and robust. Additional robustness may be provided by incorporating shock-absorber material between the flexible strip and the electromagnetic coil, and protecting the mirror by covering the front surface of the scanner module with a transparent shield.
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