Optical writing device, image forming apparatus, and method and program product for controlling optical writing device

A method for controlling an optical writing device that forms an electrostatic latent image on a photosensitive element with a binary light source capable of controlling two statuses which are a switch on status and a switch off status, the method comprising:

• acquiring multilevel pixel information in which one pixel is expressed in multilevel scales, the multilevel pixel information being information of each pixel for forming an image as the electrostatic latent image, and storing the acquired multilevel pixel information in a storage medium for each main scanning line;
• and
• exposing the photosensitive element with the binary light source with a period corresponding to N-fold in a sub scanning direction resolution of the stored multilevel pixel information, wherein N is a positive integer, so that the N times exposures corresponds to an exposure for one pixel in the original resolution;
• and
• acquiring a control value to control the switch on status and the switch off status of the binary light source, in controlling the binary light source in the N times exposures for each pixel, on the basis of lighting rate information, the lighting rate information being for converting the multilevel scales into a lighting rate in the N times exposures.

A computer program product comprising a non-transitory computer-readable medium having computer-readable program codes embodied in the medium for controlling an optical writing device that forms an electrostatic latent image on a photosensitive element with a binary light source capable of controlling two statuses which are a switch on status and a switch off status, the program codes when executed causing a computer to execute:

• acquiring multilevel pixel information in which one pixel is expressed in multilevel scales, the multilevel pixel information being information of each pixel for forming an image to be formed as the electrostatic latent image, and storing the acquired multilevel pixel information in a storage medium for each main scanning line;
• and
• exposing the photosensitive element with the binary light source with a period corresponding to N-fold in a sub scanning direction resolution of the stored multilevel pixel information, wherein N is a positive integer, so that the N times exposures corresponds to an exposure for one pixel in the original resolution;
• and
• acquiring a control value to control the switch on status and the switch off status of the binary light source, in controlling the binary light source in the N times exposures for each pixel, on the basis of lighting rate information, the lighting rate information being for converting the multilevel scales into a lighting rate in the N times exposures.