首页> 外国专利> MULTI-FOCAL LASER SCANNING BAR CODE SYMBOL READING SYSTEM EMPLOYING A SCAN DATA SIGNAL PROCESSOR HAVING A VARIABLE PASS-BAND FILTER STRUCTURE WITH FREQUENCY CHARACTERISTICS CONTROLLED BY MEASURING THE BEAM SPOT SPEED OF THE LASER SCANNING BEAM PRODUCING THE ANALOG SCAN DATA SIGNAL BEING PROCESSED BY SAID SCAN DATA SIGNAL PROCESSOR

MULTI-FOCAL LASER SCANNING BAR CODE SYMBOL READING SYSTEM EMPLOYING A SCAN DATA SIGNAL PROCESSOR HAVING A VARIABLE PASS-BAND FILTER STRUCTURE WITH FREQUENCY CHARACTERISTICS CONTROLLED BY MEASURING THE BEAM SPOT SPEED OF THE LASER SCANNING BEAM PRODUCING THE ANALOG SCAN DATA SIGNAL BEING PROCESSED BY SAID SCAN DATA SIGNAL PROCESSOR

机译：多焦点激光扫描条形码符号读取系统，采用具有可变通带结构的扫描数据信号处理器，该通带具有频率特性，该频率特性通过测量激光扫描信号的扫描点的扫描速度来控制激光扫描信号的频点数据信号处理器

页面导航

摘要
著录项
相似文献

摘要

The zone laser scanning systems by processing analog scan data signals with a scan data signal processor having a plurality of pass-band filters and amplifiers that are automatically selected for passing only the spectral components of an analog scan data signal produced when a bar code symbol is scanned at a particular focal zone in the laser scanning system. Two or more different pass band filter structures can be provided for use in the scan data signal processor, wherein each pass-band filter structure is: tuned to the spectral band associated with a particular focal zone in the laser scanning system. When a bar code, symbol is scanned by a laser beam focused within the first focal zone or scanning range of the system, the pass-band filter structure associated with this focal zone or scanning range is automatically switched into operation using a control signal produced by determining the spot speed of the laser scanning beam producing the analog scan data signal being processed. Only spectral components associated with the produced analog scan data signal and noise existing over this pass-band are allowed within the analog signal processor. By virtue of the present invention, first and second derivative signals can be generated and processed to produce a corresponding digital scan data signal for use in subsequent digitizing and decode processing operations, without compromising system performance due to the destructive effects of thermal and substrate noise outside the spectral pass-band of interest for the bar code symbol being scanned.

机译：通过使用具有多个通带滤波器和放大器的扫描数据信号处理器来处理模拟扫描数据信号的区域激光扫描系统，这些通带滤波器和放大器被自动选择为仅使当条形码符号为零时产生的模拟扫描数据信号的频谱分量通过在激光扫描系统中的特定焦点区域进行扫描。可以提供两个或更多个不同的通带滤波器结构以供在扫描数据信号处理器中使用，其中，每个通带滤波器结构被：调谐到与激光扫描系统中的特定聚焦区相关联的光谱带。当条形码，符号被聚焦在系统第一聚焦区域或扫描范围内的激光束扫描时，与该聚焦区域或扫描范围相关联的通带滤波器结构会使用由确定产生正在处理的模拟扫描数据信号的激光扫描束的光斑速度。在模拟信号处理器中，只允许与产生的模拟扫描数据信号相关联的频谱分量和在该通带上存在的噪声。借助于本发明，可以产生和处理一阶和二阶导数信号以产生相应的数字扫描数据信号，以供随后的数字化和解码处理操作使用，而不会由于外部热和衬底噪声的破坏性影响而损害系统性能。扫描的条形码符号的感兴趣的光谱通带。

著录项

公开/公告号US6588663B1

专利类型
公开/公告日2003-07-08

原文格式PDF
申请/专利权人 METROLOGIC INSTRUMENTS INC.;
展开▼

申请/专利号US20000501903
发明设计人 MARK LUCERA;FRANK CHECK;C. HARRY KNOWLES;XIAOXUN ZHU;LEROY DICKSON;
展开▼

申请日2000-02-10
分类号G06K71/00;
国家 US
入库时间 2022-08-22 00:05:13

相似文献

专利
外文文献
中文文献