US Patent 7233419 Scanner having a self collection light source

A scanner using a self-collection light source, is composed of a light source either with its tube walls coated with a layer of total reflective material, or a tube wall made to have a converging lens-like wall, so that the light source itself has built-in light converging ability. The original scattered light is first collected into a light beam before emitted to the scan line on the document. Thus, the light flux on the scan line can be substantially enhanced. Furthermore, by including the auxiliary light sources on both sides of this kind of main light source with self-collection capability, associating with a light intensity adjusting control circuitry, The light flux density on the two sides of the main light source is improved, so that it effectively improves the flux uniformity of light incident on the light detector.