Patent ID: 9294651
Filing Date: 2016-03-22
CPC Classification: H04N

Claim Text:
1. An image reading device for reading an image on a document with visible light and non-visible light being switchingly applied thereto, comprising: an image sensor which reads the image on the document to output an image signal; a light source which switchingly emits visible light and non-visible light; a lighting control unit which controls lighting periods of the light source, and an adjusting unit which shortens a first light source lighting period for applying non-visible light in case the level of the image signal upon application of non-visible light is higher than a first reference level, extends the first light source lighting period in case the level of the image signal upon application of non-visible light is lower than the first reference level, shortens a second light source lighting period for applying visible light in case the level of the image signal upon application of visible light is higher than a second reference level, and extends the second light source lighting period in case the level of the image signal upon application of visible light is lower than the second reference level, while the image sensor is reading the image on the document, wherein the lighting control unit is adapted to perform control such that the first light source lighting period is longer than the second light source lighting period at the time of initial setting before the image sensor starts to read the image on the document.