Method and apparatus for ensuring precise angular orientation of an optical sensing unit on a housing of an optical imaging device

An apparatus adapted for use with an optical imaging device that includes a housing formed with a lens-mounting aperture, an optical lens unit mounted on the housing at one side of the lens-mounting aperture, and an optical sensing unit mounted on the housing at an opposite side of the lens-mounting aperture, said apparatus being adapted to assist in precise mounting of the optical sensing unit on the housing, and comprising:

• a testing frame;
• a downwardly facing test image piece disposed at an upper portion of said testing frame, the test image piece having an image thereon that includes two intersecting axes forming four quadrants, each of the quadrants being provided with a pattern;
• a test lens unit disposed on said testing frame below said test image piece, said testing frame being adapted to secure the housing thereon below said test lens unit such that the aperture is registered with said test lens unit along an optical axis, the optical sensing unit being loosely mounted on the housing at the opposite side of the aperture such that the optical sensing unit is adjustable relative to the aperture along transverse axes of a sensing plane that is transverse to the optical axis and such that the optical sensing unit is rotatable relative to the housing about a rotary axis that is generally aligned with the optical axis when the housing is secured initially on said testing frame, the optical sensing unit being operable so as to generate image signals corresponding to a captured image of said test image piece that was received by the optical sensing unit via said test lens unit;
• and
• a control device adapted to be coupled to the optical sensing unit for processing the image signals so as to determine a skew angle of the captured image with reference to image data associated with a reference base angle and stored in a previously established correcting database;
• whereby, the angular orientation of the optical sensing unit relative to the housing can be corrected in accordance with the skew angle determined by said control device.