Patent ID: 6969005

Claim:
An optical unit for an optical symbol reader comprising: a light source emitting a laser beam; an optical scanner having an oscillating member with a reflection face for reflecting the laser beam emitted from the light source, the optical scanner scanning an optical symbol with the laser beam by angularly oscillating the reflection face owing to an electromagnetic force; and a photo detector detecting a light reflected from the optical symbol to convert a change in the amount of received light corresponding to a pattern of the optical symbol into an electric signal; wherein the optical scanner comprises a loose bearing structure for supporting the oscillating member to angularly oscillate freely with respect to a fixing member, the loose bearing structure having a shaft and a bearing bore with a gap formed between an outer diameter of the shaft and an inner diameter of the bearing bore, and the optical scanner further comprises a resiliently urging member for resiliently urging the oscillating member in a predetermined direction so that a part of an outer circumferential face of the shaft may be contacted with an inner circumferential face of the bearing bore and wherein between the shaft and the bearing bore during angular oscillation, a percentage of a rolling friction component is larger than a sliding friction component.