Sheet feeder

The invention concerns an apparatus for transferring sheet-like objects from a stack, said apparatus including separate lifting elements gripping by suction to the upper surface of the sheet-like object to be transferred, positioned in a row extending over the stack of the sheet-like objects, and transfer elements for transferring the lifted sheet-like object. The suction effect of the lifting elements is controlled by means of a control device including a light source making a substantially line-shaped illumination pattern. The illumination of the light source is focused at an inclined angle to the surface of the sheet stack, substantially parallel to the lifting element row. A camera means for observing the illumination pattern forwards information about the uniformity of the uppermost layer of the stack.