Patent ID: 7339729

Claim:
A focusing device comprising: a base module including a housing, a shaft, and at least two bearings, the housing having an inner surface and a passageway formed in the inner surface, the shaft being pivotally disposed in a bottom portion of the housing and perpendicular to a longitudinal axial direction of the passageway, the shaft having a part located in the passageway, and the at least two bearings being respectively disposed on an upper-left portion and an upper-right portion of the inner surface of the housing; and a telescopic tube module including a tubular body, a bottom reinforced member, and an upper reinforced member, the bottom reinforced member being disposed on a bottom portion of an outer surface of the tubular body and extending along a longitudinal axial direction of the tubular body, the upper reinforced member being disposed on an upper-left portion and an upper-right portion of the outer surface of the tubular body, the upper reinforced member forming at least two rails respectively located on the upper-left portion and the upper-right portion of the outer surface of the tubular body and extending along the longitudinal axial direction of the tubular body; wherein the tubular body is slidably disposed in the passageway along the longitudinal axial direction thereof the shaft supports the bottom reinforced member, and the at least two bearings respectively support the at least two rails of the upper reinforced member.