Hybrid Side Plate Rod Lens Array for Thermal Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Rod lens arrays used in LED print heads and contact image sensors experience dimensional variations due to changes in humidity and temperature, leading to unstable light illumination and image formation/image reading quality.
Innovation Solution
A rod lens array design featuring hybrid side plates with a first side plate of high machinability and a second side plate of lower machinability and smaller linear expansion coefficient, which are press bonded together to minimize dimensional changes and stress, ensuring stable performance across varying environments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a single plate member is used for substrates of a rod lens array, then the structure is simple and easy to manufacture, but the dimensional stability deteriorates due to thermal expansion and moisture absorption
Solution Approach 1:
The patent applies composite materials by constructing the side plates from two different plate members with distinct properties. The first plate member provides dimensional stability with low thermal expansion and moisture absorption, while the second plate member offers high machinability. This composite structure resolves the contradiction by combining materials that individually excel in different aspects, achieving both dimensional stability and ease of manufacture through their synergistic integration.
Solution Approach 2:
The patent implements local quality by assigning different functional characteristics to different regions of the side plate structure. The first plate member (inner layer) is optimized for dimensional stability with low expansion coefficients, while the second plate member (outer layer) is optimized for machinability. This spatial differentiation of material properties allows each region to fulfill its specific functional requirement, resolving the contradiction between stability and manufacturability.
2Ease of manufacture
If plate members with high machinability are used for side plates, then the ease of manufacture is improved, but the dimensional variation worsens under environmental changes
Solution Approach 1:
The patent resolves this contradiction by using composite materials where the first plate member (with low thermal expansion and moisture absorption) ensures dimensional precision, while the second plate member (with high machinability) ensures ease of manufacture. The combination allows the side plates to be easily manufactured while maintaining dimensional stability under environmental variations.
Solution Approach 2:
The patent applies local quality by making the inner portion of the side plate (first plate member) have properties optimized for dimensional precision, while the outer portion (second plate member) has properties optimized for machinability. This localized differentiation allows the machinable outer layer to facilitate manufacturing while the stable inner layer maintains dimensional precision.
3Device complexity
If a single-material side plate is used, then the device complexity is reduced, but the ability to withstand environmental stress worsens
Solution Approach 1:
The patent addresses this contradiction by employing composite materials in the side plate construction. The first plate member provides resistance to thermal expansion and moisture absorption, enhancing environmental stress resistance. The second plate member provides high machinability. Together, they create a side plate structure that withstands environmental stress while maintaining reasonable complexity through a systematic two-layer design.
Solution Approach 2:
The patent implements local quality by assigning the first plate member (inner layer) the function of withstanding environmental stress through low expansion properties, while the second plate member (outer layer) handles manufacturing requirements. This functional differentiation within the side plate structure enables environmental stress resistance without excessive device complexity.
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
The design achieves stable light illumination and image formation/image reading performance by reducing dimensional variations and stress, maintaining consistent quality despite environmental changes.
Implementation Method 1
a second side plate provided on outer side of the first side plate, and having hardness higher than hardness of the first side plate, and a linear expansion coefficient smaller than linear expansion coefficient of the first side plate
Data Source
Figure 1
Figure 2
Figure 3A~3B
AI summary
Provided is a rod lens array that includes: a plurality of lenses; and a pair of side plate sections interposing side surfaces of the respective lenses in between to hold the lenses, and each including a first side plate provided adjacent to the lenses, and a second side plate provided on outer side of the first side plate, and having machinability lower than machinability of the first side plate, and a linear expansion coefficient smaller than linear expansion coefficient of the first side plate.