Patent ID: 7271402
Filing Date: 2007-09-18
Classification: H04N

Abstract:
1. An optical alignment method for an optical module that includes a housing unit, a light-sensing unit disposed in the housing unit, and a lens unit for focusing light onto the light-sensing unit, said optical alignment method comprising the steps of: (a) through image-capturing techniques, finding a light-sensing component of the light-sensing unit and a predetermined object reference point, and determining an actual total optical path length between the light-sensing component and an object position having a predetermined distance relation with the predetermined object reference point; (b) subtracting a correction optical distance from the actual total optical path length to obtain a corrected total optical path length; (c) finding an imaginary first center line located at a position that divides the corrected total optical path length into equal half distances; (d) through image-capturing techniques, finding first and second edges of the lens unit that are opposite to each other in a direction of a light-sensing axis of the light-sensing unit from the light-sensing component to the object position, and determining a lens length between the first and second edges; (e) finding an imaginary second center line located at a position that divides the lens length into equal half distances; and (f) assembling the lens unit to the housing unit in such a manner that the imaginary second center line coincides with the imaginary first center line.