1. Field of the Invention
The disclosures discussed herein related to an optical writing device, an image forming apparatus, and a control method of the optical writing device.
2. Description of the Related Art
There is an electrophotographic image forming apparatus including a light emitting diode array (hereinafter called “LEDA”) for forming an electrostatic latent image on a photoreceptor as an optical writing unit. However, when the LEDA is used, the electrostatic latent image will not be formed uniformly due to inconsistent light intensity of each of LED elements, which may degrade the image quality.
Hence, there is disclosed a technology to prevent such degradation of the image quality due to the inconsistent light intensity. For example, Japanese Laid-open Patent Publication No. 2003-220728 (hereinafter referred to as “Patent Document 1”) discloses a technology in which the light intensity of each of the LED elements is measured, correction data are created based on the measured light intensity of each of the LED elements, and each of the LED elements is driven based on a corresponding one of the corrected data so as to prevent the degradation of the image quality due to the inconsistent light intensity.
In the above technology disclosed in Patent Document 1, a central processing unit (CPU) controlling the LEDA transfers the correction data from memory to an LED driver, which then controls each of the LED elements based on a corresponding one of the correction data. Note that when the power supplied from a power source to the LEDA is instantaneously cut off (hereinafter also called “instantaneous cutoff”), the LED driver is initialized. Hence, it may be necessary to transfer the correction data to the LED driver again.
However, in a case where the instantaneous cutoff has occurred, for example, within a polling period of the CPU that controls the LEDA, the cutoff of the power supply to the LEDA will not be detected. Accordingly, when the instantaneous cutoff occurs immediately after the startup of the apparatus, the electrostatic latent image is formed in a state where the LED driver is initialized. Hence, the quality of the image formed may be degraded due to inconsistent light intensities of the LED elements.
USPTO Backgrounds
USPTO Backgrounds