Image forming apparatus for detecting and correcting thickness and area ratio of toner layer

摘要

An image forming apparatus includes an image forming unit having an exposure unit and a developing unit; a detection unit configured to detect a thickness and an area ratio of a toner layer of a pattern image formed by the image forming unit; a storage unit configured to store data indicating permissible ranges for the thickness and the area ratio of the toner layer; and a correction unit configured to change, when the thickness or the area ratio of the toner layer detected by the detection unit falls outside the corresponding permissible range indicated by the data stored in the storage unit, a spot diameter of the laser beam so that the thickness and the area ratio of the toner layer respectively fall within the permissible ranges.

主权项

1. An image forming apparatus comprising:
an image forming unit including an exposure unit configured to form a latent image by exposing a photosensitive member with a laser beam, and a developing unit configured to form a toner image by causing toner to adhere to the latent image; a detection unit configured to detect a thickness and an area ratio of a toner layer of a pattern image as the toner image formed by the image forming unit; a storage unit configured to store data indicating permissible ranges for the thickness and the area ratio of the toner layer; and a correction unit configured to change, when the thickness or the area ratio of the toner layer detected by the detection unit falls outside the corresponding permissible range indicated by the data stored in the storage unit, a spot diameter of the laser beam so that the thickness and the area ratio of the toner layer respectively fall within the permissible ranges, wherein the correction unit comprises a lens arranged on an optical path of the laser beam between the photosensitive member and the exposure unit, and an adjustment unit configured to move the lens along the optical path of the laser beam.