摘要 |
A medium transporting state detecting device includes an irradiation optical system which irradiates a sheet-shaped medium with non-coherent light, a light receiving optical system which receives diffuse reflected light from the medium, a diffuse reflected light acquisition unit which acquires an intensity of the diffuse reflected light for each constant period;, a frequency component analyzing unit which performs analyzing a frequency component of reflected light intensity arrays where the intensity is temporally and sequentially shifted, a period calculating unit which obtains an actual period of a temporal change in a real number portion of a frequency component of a specified frequency among the analyzed frequency components, and a velocity detecting unit which obtains at least one of a difference between an actual velocity and a target velocity and the actual velocity based on the actual period and the target period. |