An image reader configured to focus light emitted from a light source and reflected by an object-to-be-read, and to read an image of the object-to-be-read, the image reader comprising: - a board ; - a light source ; - a line sensor assembly including a plurality of photosensitive elements formed on one surface of the board along a main scanning direction; - a lens array assembly including a plurality of lenses arrayed along the main scanning direction, and configured to focus the reflected light onto the line sensor assembly ; - a light shield configured to support a portion of the lens array assembly at the line-sensor assembly side, and to block light other than the light focused by the lens array assembly ; - a transparent member made of transparent material retaining the lens array assembly and the light shield in a retainer space and configured to guide the light from the light source through an interior of the transparent member , and emit the guided light to the object-to-be-read, and covering a portion of the lens array assembly at the object-to-be-read side and the light shield ; and - a fastener configured to fasten the transparent member to the board , and by pressing force from the board by the fastening, to bring the light shield into contact with the transparent member , to bring the lens array assembly into contact with the transparent member via the light shield , or to bring the light shield and the lens array assembly into contact with the transparent member , - the fastener being an engagement portion provided to the transparent member , a boss formed on the transparent member , a screw, a clip, an adhesive, or a combination of an elastic member with projections formed on the respective surfaces of the transparent member located opposite to the retainer space . - a board ; - a light source ; - a line sensor assembly including a plurality of photosensitive elements formed on one surface of the board along a main scanning direction; - a lens array assembly including a plurality of lenses arrayed along the main scanning direction, and configured to focus the reflected light onto the line sensor assembly ; - a light shield configured to support a portion of the lens array assembly at the line-sensor assembly side, and to block light other than the light focused by the lens array assembly ; - a transparent member made of transparent material retaining the lens array assembly and the light shield in a retainer space and configured to guide the light from the light source through an interior of the transparent member , and emit the guided light to the object-to-be-read, and covering a portion of the lens array assembly at the object-to-be-read side and the light shield ; and - a fastener configured to fasten the transparent member to the board , and by pressing force from the board by the fastening, to bring the light shield into contact with the transparent member , to bring the lens array assembly into contact with the transparent member via the light shield , or to bring the light shield and the lens array assembly into contact with the transparent member , - the fastener being an engagement portion provided to the transparent member , a boss formed on the transparent member , a screw, a clip, an adhesive, or a combination of an elastic member with projections formed on the respective surfaces of the transparent member located opposite to the retainer space . <EOS>