Patent ID: 6906830

Claim:
An image scanner for use in reading image information, comprising: a driving side conveying roll for conveying a manuscript including said image information to be read past a stationary reading position; a driven side conveying roll which is located above said driving side conveying roll and which rotates by rolling-contact with said driving said conveying roll; a manuscript sensor for detecting said manuscript when a head of said manuscript arrives at a position near the rolling-contact position between said driving side conveying roll and said driven side conveying roll; conveying roll driving means for starting a rotation of said driving side conveying roll when said manuscript sensor has detected an arrival of said head of said manuscript; light-electricity conversion means for carrying out light-electricity conversion of said image information per one line in a main-scanning direction of said manuscript from a side of one surface of said manuscript at said stationary reading position on a conveying route when said driving said conveying roll is started to rotate by said conveying roll driving means and said manuscript is thereby started to move toward the sub-scanning direction between said driving side and said driven side conveying rolls, said stationary reading position existing downstream of said conveying route form the rolling-contact position by a predetermined distance; a first light source for emitting light onto said stationary reading position from a side of another surface of said manuscript opposite to said one surface thereof; a second light source for emitting light onto said stationary reading position from a side of the same surface of said manuscript as said one surface thereof; and light source switching control means for selectively rendering either said first light source or said second light source ON to read said image information included in said manuscript, dependent on whether said image information is defined by a reflected light reflected by said manuscript or by a transmitting light transmitting through said manuscript.