Abstract: A water content determination apparatus which are capable of precisely determining water content contained in a medium regardless of an environment where an image forming apparatus is installed. The water content determination apparatus. A signal in accordance with presence or absence of a medium in an electrostatic capacitance region formed on a paper path is outputted where the medium for image forming is conveyed. Temperature in the water content determination apparatus is determined based on an output signal of the detection device in absence of the medium passing in the electrostatic capacitance region. Water content contained in the medium is determined based on the output signal of the detection device in absence of the medium passing in the electrostatic capacitance region, the output signal of the detection device in presence of the medium passing in the electrostatic capacitance region, and the temperature determined by the temperature determination device.

Abstract: An image forming apparatus in which the intensity of a light beam used to form a latent image is switched in response to a change in resolution. A laser emits a light beam for forming a latent image on a photosensitive drum. A polygon mirror scans the emitted light beam. BD sensors detect the scanned beam. A timing controller selects the preferable timing from a storage device table according to the intensity of the light beam or the resolution when controlling the light emission timing of the lasers in response to a detection of timing of the detected light beam.

Abstract: An image forming apparatus for forming an image by irradiating a charged surface of a photosensitive member with a laser beam depending on a picture signal to form an electrostatic latent image, visualizing the latent image with a recording agent, and transferring the visualized image onto a recording medium; includes a circumferential position detection unit for detecting a circumferential position of the photosensitive member irradiated with the laser beam and an APC circuit for controlling a light quantity of the laser beam so as to provide a target light quantity varying depending on the detected circumferential position.

Abstract: An image forming apparatus for forming an image by irradiating a charged surface of a photosensitive member with a laser beam depending on a picture signal to form an electrostatic latent image, visualizing the latent image with a recording agent, and transferring the visualized image onto a recording medium; includes a circumferential position detection unit for detecting a circumferential position of the photosensitive member irradiated with the laser beam and an APC circuit for controlling a light quantity of the laser beam so as to provide a target light quantity varying depending on the detected circumferential position.