| 摘要 |
A machine-readable symbol reader can include a housing, a window, an illumination source, a wedge-shaped optical element, and a sensor array. Illumination can be coupled into the optical element through a base surface of the optical element and out of the optical element through a leg surface of the optical element. Illumination beams coupled out of the optical element through the leg surface can be parallel or substantially parallel to one another, and can exit the machine-readable symbol reader at a grazing angle to illuminate a machine-readable symbol at a grazing angle. |
| 主权项 |
1. A machine-readable symbol reader comprising:
an optical element having a base, an end, a first major face, a second major face, a thickness, and a length between the base and the end, the second major face non-parallel to the first major face and opposed across the thickness of the optical element from the first major face, the thickness which varies along the length of the optical element, the first and the second major faces which propagate a diminishing amount of light passing through the optical element along the length thereof from the base toward the end by total internal reflection and which exit the light passing through the optical element from the base by refraction through at least one of the first or second major faces; an illumination source positioned to transmit illumination toward the base of the optical element; a housing that includes a window, the window positioned to pass illumination coupled out of the first major face of the optical element; and an optical sensor array. |
