Patent ID: 7618039

Claim:
A sheet detecting apparatus for use in an image forming apparatus, wherein the image forming apparatus forms an image on an image carrier based on input image data and transfers the image onto a transported sheet to form an image on the sheet, and the sheet detecting apparatus is used for detecting a transport state of the sheet before the image is transferred to the sheet, the sheet detecting apparatus comprising: a linear light emitting section being a plurality of light sources are arranged in a line for irradiating a sheet transport path with light; a plurality of light receiving sections for directly receiving the light from the linear light emitting section via the sheet transport path, wherein the plurality of light receiving sections are opposed to the linear light emitting section and arranged in a line along a direction perpendicular to a sheet transport direction; and a hood means for causing the light from the linear light emitting section to enter each light receiving section in a substantially straight direction via respective locations on the transport path, wherein the light emitted from each of the plurality of light sources is emitted in a direction perpendicular to the sheet transport direction and is directly incident on each of the plurality of light receiving sections, which are opposed to the liner light emitting section, via the sheet transport path, the hood means passes light from the liner light emitting section, only from immediately above each of the light receiving sections, into the corresponding light receiving sections, and the transported sheet passes in between the light emitting section and the plurality of light receiving sections.