Abstract: An image forming apparatus includes a controller. The controller controls to perform a first operation in which a first potential difference is formed between a supplying member and a developing member, the first potential difference being a potential difference in a direction in which an electrostatic force in a first direction toward the developing member from the supplying member is acted on toner charged to a normal polarity, and a second operation in which a second potential difference is formed between them and in a second direction opposite to the first direction. When an image forming operation is performed, the controller controls timing for changing from the first operation to the second operation based on information on presence or absence of a recording material in a conveyance passage toward a transferring portion in a non-image forming operation before the recording material is nipped and conveyed at the transferring portion.

Abstract: An image forming apparatus includes a rotating polygon mirror configured to rotate and reflect the first laser beam and the second laser beam, a first generation unit configured to generate a first signal based on timings at which the respective first laser beams, a second generation unit configured to generate a second signal for determining a timing to form an electrostatic latent image on the second image bearing member with the second laser beam based on the first signal and a correction value, and a calculation unit configured to calculate the correction value based on the output of the detection unit, in which the calculation unit calculates the correction value based on the signal output from the detection unit in a period of time that has passed until the rotating polygon mirror reaches steady rotation since it has started to be driven to rotate.

Abstract: An image forming apparatus includes a rotating polygon mirror configured to rotate and reflect the first laser beam and the second laser beam, a first generation unit configured to generate a first signal based on timings at which the respective first laser beams, a second generation unit configured to generate a second signal for determining a timing to form an electrostatic latent image on the second image bearing member with the second laser beam based on the first signal and a correction value, and a calculation unit configured to calculate the correction value based on the output of the detection unit, in which the calculation unit calculates the correction value based on the signal output from the detection unit in a period of time that has passed until the rotating polygon mirror reaches steady rotation since it has started to be driven to rotate.

Abstract: An image forming apparatus includes a rotating polygon mirror configured to rotate and reflect the first laser beam and the second laser beam, a first generation unit configured to generate a first signal based on timings at which the respective first laser beams, a second generation unit configured to generate a second signal for determining a timing to form an electrostatic latent image on the second image bearing member with the second laser beam based on the first signal and a correction value, and a calculation unit configured to calculate the correction value based on the output of the detection unit, in which the calculation unit calculates the correction value based on the signal output from the detection unit in a period of time that has passed until the rotating polygon mirror reaches steady rotation since it has started to be driven to rotate.

Abstract: An image forming apparatus includes a rotating polygon mirror configured to rotate and reflect the first laser beam and the second laser beam, a first generation unit configured to generate a first signal based on timings at which the respective first laser beams, a second generation unit configured to generate a second signal for determining a timing to form an electrostatic latent image on the second image bearing member with the second laser beam based on the first signal and a correction value, and a calculation unit configured to calculate the correction value based on the output of the detection unit, in which the calculation unit calculates the correction value based on the signal output from the detection unit in a period of time that has passed until the rotating polygon mirror reaches steady rotation since it has started to be driven to rotate.