Patent ID: 7871005
Filing Date: 2011-01-18
Classification: G06K

Abstract:
1. An information reader, comprising: a light receiving optical system that sets a readable area, receives image forming light from a display medium placed in the readable area, and forms a code image from the image forming light to optically read, from the code image, an information code marked on the display medium; a marker light source that emits marker light to the display medium along a light emission axis of the marker light source to place the display medium in the readable area; and a supporting member that supports the marker light source and the light receiving optical system, wherein the light receiving optical system comprises: wherein the supporting member supports the marker light source and the light receiving sensor such that the sensor axis of the light receiving sensor and the light emission axis of the marker light source are substantially parallel to each other, wherein an optical axis of the lens and the light emission axis of the marker light source are separated by an inter-axis distance Da, and wherein the sensor axis of the light receiving sensor is differentiated from the optical axis of the lens by an offset value F satisfying a relationship of F=Da×Di/Do such that the sensor axis of the light receiving sensor is shifted from the optical axis of the lens in a direction away from the marker light source.