Projection aligner

A projection aligner arranged to scan a plurality of light beams over the mask in a first direction to transfer an image of a pattern formed on the mask to the object by the light beams passed through the mask, said projection aligner comprising:

• a plurality of optical systems, each of said optical systems projecting different one of the light beams passed through the mask onto the object to transfer different part of the image of the pattern on the mask to the object;
• wherein each of said optical systems includes:
• a lens unit having a positive power, said lens unit having an optical axis parallel to the first direction;
• a reflector provided to one side of said lens unit to reflect back light passed through said lens unit, said reflector being supported movably in the first direction and in a second direction, the second direction being parallel to the object and perpendicular to the first direction;
• and
• a deflector provided to other side of said lens unit, said deflector having first and second mirrors, said first mirror deflecting the light beam passed through the mask toward said reflector through said lens unit, said second mirror deflecting the light beam reflected by said reflector and passed through the lens unit toward the object, said deflector being supported movably in a direction perpendicular to said object.