| 摘要 |
An optical symbol scanner assembly includes an illumination assembly to facilitate detection and decoding small 2-D matrix bar code symbols or other optically read symbols that are laser etched or printed on the surface of microelectronics modules or other small articles. A hand-held scanner has an array of LEDs or laser diodes on its distal face that produces light to illuminate the symbol. There is also a focussing lens on the distal face and an imager device positioned behind the lens. The illumination assembly is mounted on the distal face of the scanner device. In this assembly, a lens barrel member has an optic axis aligned with the optic axis of the scanner, and a light pipe is positioned adjacent the lens barrel member. The light pipe has a flat proximal face against the array of LEDs, and an angulated distal face for projecting the illumination at a sharp angle relative to the optic axis. The tip of the illumination assembly is in near contact with the article to read the symbol. The lens barrel member may carry an auxiliary lens. Preferably, there is a pair of light pipes disposed on opposite sides of said lens barrel member. Alternatively, the scanner may be configured as a fixed device, for reading symbols on articles that flow past it without contact.
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