Laser Unit Reference Voltage Smoothing for Image Quality Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The deviation in reference potentials between the main board and the LD board due to increased harness resistance and current flow causes improper adjustment of the semiconductor laser's light emission amount, leading to image quality issues in image forming apparatuses.
Innovation Solution
The implementation of an LD board with a voltage generation circuit, switching circuit, and smoothing circuit to generate and stabilize the reference voltage, ensuring accurate light emission control of the semiconductor laser.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the harness between the main board and LD board is made longer to accommodate spatial layout requirements, then the spatial flexibility is improved, but the resistance of the harness increases causing voltage difference in reference potentials
Solution Approach 1:
The patent applies equipotentiality by providing separate reference potential sections (main reference potential section on main board and LD reference potential section on LD board) that are electrically connected through the harness. This ensures both boards operate at the same reference potential level despite the harness resistance, eliminating voltage differences and potential instability caused by long harness connections.
2Power
If the current flowing through the harness is increased to improve signal transmission, then the signal transmission capability is improved, but the voltage difference due to harness resistance increases causing deviation in reference voltage
Solution Approach 1:
The patent segments the reference potential provision into separate reference potential sections on each board (main reference potential section and LD reference potential section). Each section independently provides reference potential to its respective board, eliminating the dependency on high current flow through the harness and preventing voltage drops that would affect reference voltage accuracy.
Solution Approach 2:
The patent introduces an electrical connection (harness) between the reference potential sections that acts as an intermediary to equalize the reference potentials. This intermediary connection ensures that both boards share a common reference potential level without requiring high current flow, thus maintaining reference voltage accuracy while enabling signal transmission.
3Manufacturing precision
If the reference voltage adjustment is made more sensitive to achieve precise light emission control, then the light emission precision is improved, but the deviation between intended and actual reference voltage increases due to harness resistance
Solution Approach 1:
By establishing equipotential connection between the main board and LD board through the harness connecting the reference potential sections, the patent ensures that the reference voltage remains consistent and reliable. This allows the LD driver to accurately adjust light emission based on the reference voltage from the controller without deviation caused by harness resistance.
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
Stabilizes the reference voltage, thereby ensuring precise light emission adjustment of the semiconductor laser, improving image quality and reducing deviations in the image forming process.
Implementation Method 1
a smoothing circuit configured to generate the reference voltage by smoothing the ON-voltage and the OFF-voltage output by the switching circuit
Data Source
AI summary
An image forming apparatus includes a laser unit including a semiconductor laser, a polygon mirror, an LD driver, and an LD board including an LD reference potential section. The image forming apparatus includes a photoconductor drum, a controller configured to output a pulse-width modulation signal to indicate a reference potential, and a main board including a main reference potential section configured to provide the reference voltage of the controller, the main reference potential section being electrically connected to the LD reference potential section via a harness. The LD board includes a voltage generation circuit configured to generate a particular voltage, a switching circuit configured to output an ON-voltage and an OFF-voltage alternately based on the pulse-width modulation signal, and a smoothing circuit configured to generate the reference voltage by smoothing the ON-voltage and the OFF-voltage output by the switching circuit.