| 摘要 |
An automatic data collection device, such as a scanner-type device, is provided with an afocal optical element, such as an afocal lens, that operates in conjunction with a scanning mirror to scan a target machine-readable symbol using a scanning beam. The scanning mirror deflects a light beam into the afocal lens. The afocal lens operates to change a resolution or width of the scanning beam for far-field scanning, for example, where resolution is increased by the afocal lens. The afocal lens can also operate to change the resolution or width of the scanning beam for near-field scanning, for example, where resolution is decreased by the afocal lens. |
