Optical Scanning Device Driving Signal Correction for Photoconductor Density
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional image forming apparatuses face challenges in stably suppressing density unevenness in the rotation direction of photoconductor drums while maintaining productivity.
Innovation Solution
An image forming apparatus and method that includes a photoconductor drum, an optical scanning device, and a density detector, where the optical scanning device can correct the driving signal for the light source based on density variation detection, adjusting the correction period and strength of the driving signal to stabilize image density across the rotation period of the drum.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional image forming apparatuses use fixed correction methods for density unevenness, then the correction process is simple, but the image density remains uneven in the rotation direction of the photoconductor drum
Solution Approach 1:
The patent implements dynamic correction by adjusting the light emission amount of the light source based on detected density unevenness. The correction amount varies according to the position on the photoconductor drum, transforming a static correction approach into a dynamic one that adapts to rotational position and density variations.
Solution Approach 2:
The patent employs a feedback mechanism where a detector measures the density of the developed image, and the measured density unevenness is fed back to adjust the light emission amount. This closed-loop feedback system continuously monitors and corrects density variations, improving image density uniformity.
2Manufacturing precision
If the correction data is updated for every rotation period, then the image density uniformity is improved, but the processing time increases and productivity drops
Solution Approach 1:
The patent performs correction data acquisition and processing in advance, before the actual image formation process. By preparing correction data beforehand and storing it for use during image formation, the system avoids time-consuming calculations during production, thereby maintaining high productivity while achieving density uniformity.
Solution Approach 2:
The patent applies correction data selectively based on the detected density unevenness characteristics. Rather than applying uniform correction across all positions, the system applies partial correction only where density variations are detected, optimizing both image quality and processing efficiency.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach effectively stabilizes image density in the rotation direction of the photoconductor drum, enhancing image quality and productivity by dynamically adjusting the light emission correction data and period to match the drum's rotation speed changes.
Implementation Method 1
a photoconductor drum; an optical scanning device that drives a light source to scan a surface of the photoconductor drum and form a latent image on the surface
Data Source
AI summary
An image forming apparatus includes: a photoconductor drum; an optical scanning device that drives a light source to scan a surface of the photoconductor drum and form a latent image on the surface; a developing device that develops the latent image; and a density detector to detect density variation of an image in a rotation direction of the photoconductor drum, the image being developed by the developing device. The optical scanning device includes a processing device that is capable of correcting a driving signal for driving the light source on a basis of an output signal of the density detector to adjust at least either one of a correction period and a correction strength of correction data for the driving signal for a rotation period of the photoconductor drum.