Light-supplying optical device

A light-supplying optical device comprising:

• a light source that generates an elongated area of light along a path to illuminate an original document;
• a first optical element having a curved surface that is in said path so as to collect the light from the light source onto the original document, said curved surface being positioned relative to said path so that the light is incident on said curved surface at a non-zero angle relative to an optical axis of said curved surface, said first optical element being positioned relative to said path so that said curved surface curves the elongated area of light that the first optical element receives on the path for projection onto the original document;
• and
• a second optical element having a curved surface, said second optical element being positioned in said path so as to curve the elongated area of light that the second optical element receives on the path and so as to offset an elongated curved area of light that would otherwise be projected onto the original document by said first optical element, whereby a substantially straight elongated area of light is projected onto the original document.