| 摘要 |
PROBLEM TO BE SOLVED: To highly accurately detect image density and also to reduce a load on a device control part. SOLUTION: After a quantity of light reflected from the surface of an intermediate transfer body 5 is measured by a reflected-light detection part 102a and it is converted into a digital signal and stored into a RAM, a quantity of light reflected from a toner patch on the intermediate transfer body 5 is measured by the reflected-light detection part 102a. A signal indicating the quantity of the light reflected from the patch is inputted to a dividing circuit 28 together with a signal indicating a quantity of reflected light read from the RAM and converted into an analog signal, and it is converted into a patch relative-density by the circuit 28 and a longarithmic converting circuit 14. |
