IMAGE FORMING DEVICE AND CONTROL METHOD THEREOF CAPABLE OF MEASURING CONCENTRATION OF PATCH PATTERN FORMED IN A SENSITIZATION MEDIA OR A TRANSFER BELT WITHOUT DIFFERENCE OF LIGHT QUANTITY

摘要

PURPOSE: An image forming device and control method thereof are provided to reduce a sensing error by measuring a toner concentration by irradiating the light quantity in a reference range to a pattern.;CONSTITUTION: A concentration sensor(60) includes a light emitting unit(61) and a light receiving unit(63). The light emitting unit examines the light to a patch pattern which is formed to a toner image. The light receiving unit photoelectrically converts by light receiving the light reflected in the patch pattern. A switch unit(110) switches on and off the lighting emitting area. A control unit(90) controls on and off period of the switch unit to maintain the light quantity of the light emitting unit in a reference range.;COPYRIGHT KIPO 2011