Optical Sensor, Image Forming Device, and Method for Coorecting Tonor Concentration

摘要

The present invention is to improve detection precision degree by not increasing the number of components and by not narrowing a dynamic range. A toner concentration sensor of an embodiment is a sensor which receives reflected light by irradiating light to a toner attaching area and amplifies and outputs voltage according to the reflected light through OP-AMP. The toner concentration sensor has information capable of showing noise content which is calculated based on the property of input and output voltages of the OP-AMP.