Optical Scanning Diffractive Surface Condensing Point Displacement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical scanning apparatuses face challenges in reducing size while maintaining high image quality, particularly in adjusting condensing points in both main and sub scanning sections due to variations in environmental temperature and light source wavelength, and in managing optical performance errors.
Innovation Solution
The optical scanning apparatus incorporates a single incident optical element with a diffractive surface and a plastic molded lens, allowing for adjustment of the light source's position to compensate for wavelength variations and environmental changes, with a specific ratio of displacement amounts to maintain optimal optical performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the distance between the deflector and the image-forming optical system is shortened to reduce the apparatus size, then the apparatus size is reduced, but the magnification in the sub scanning section must be increased, making it difficult to reduce the magnification ratio and control condensing point displacement
Solution Approach 1:
The incident optical system is divided into multiple optical elements (first incident optical element and second incident optical element) with different functions. The first element focuses on main scanning condensing point control while the second element handles sub scanning condensing point control, allowing independent optimization of each section's magnification and displacement characteristics.
Solution Approach 2:
Different optical elements are designed with different local optical properties to address specific section requirements. The first incident optical element has optical characteristics optimized for main scanning, while the second incident optical element is optimized for sub scanning, enabling localized control of condensing point displacement in each scanning section.
2Device complexity
If a single incident optical element is used to reduce device complexity, then device complexity is reduced, but separate adjustment of condensing points in main and sub scanning sections becomes difficult
Solution Approach 1:
The incident optical system is segmented into multiple optical elements, each responsible for specific scanning section control. This segmentation enables independent adjustment of condensing points in main and sub scanning sections while maintaining a relatively simple overall structure.
Solution Approach 2:
The multiple incident optical elements collectively serve the dual function of controlling both main scanning and sub scanning condensing points. Each element has a specialized function, but together they provide comprehensive control capability for both scanning sections.
3Manufacturing precision
If the magnification in the main scanning section is increased to reduce the magnification ratio, then the magnification ratio is reduced, but the variation of optical performance due to shape error and placement error increases
Solution Approach 1:
By segmenting the optical system into multiple elements with different magnification characteristics, the overall magnification ratio can be reduced without requiring excessive magnification in any single element. This distributes the optical performance requirements across multiple elements, reducing the impact of individual shape and placement errors.
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 configuration enables a compact optical scanning apparatus with improved optical performance by effectively adjusting condensing points and reducing errors, ensuring high image quality and efficient scanning.
Implementation Method 1
at least one of the incident optical system and the image-forming optical system includes a diffractive surface
Data Source
AI summary
An optical scanning apparatus includes a deflector configured to deflect a light beam from a light source to cause the light beam to scan a surface to be scanned in a main scanning direction, an incident optical system that includes a single incident optical element and is configured to guide the light beam from the light source to the deflector, and an image-forming optical system configured to condense the light beam having been deflected by the deflector as condensing points on the surface to be scanned. At least one of the incident optical system and the image-forming optical system includes a diffractive surface that corrects displacement amounts of the condensing points in a main scanning section and a sub scanning section when a wavelength of the light beam from the light source varies.