发明名称 |
Barcode scanner with linear automatic gain control (AGC), modulation transfer function detector, and selectable noise filter |
摘要 |
<p>According to embodiments of the present invention, a barcode scanner platform is provided in which the gain of an analog signal representative of a barcode is controlled using a control loop. In embodiments, an MTF detector generates a value (e.g., DC) representative of a low frequency portion (wide or out of optical focus elements) of the analog signal and a second value (e.g., DC) representative of a high frequency portion (narrow elements or in optical focus elements) of the analog signal. The processor uses the first and the second values and a reference amplitude to determine a gain signal. The processor provides the gain signal to an AGC circuit that provides a linear response to the gain signal using matched JFETs. A noise filter can be enabled or disabled based on the first value, the second value, and/or the barcode scanner platform read rate.</p> |
申请公布号 |
EP2112618(A2) |
申请公布日期 |
2009.10.28 |
申请号 |
EP20090166874 |
申请日期 |
2005.04.04 |
申请人 |
MICROSCAN SYSTEMS INCORPORATED |
发明人 |
KOLSTAD, JESSE J;DAVIS, BRYAN L |
分类号 |
G06K7/10 |
主分类号 |
G06K7/10 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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