Diffuser Plate With Phase Difference Part And Mixed Microlens Shapes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for designing and producing diffuser plates with microlens arrays require repetitive calculations, lead to errors in microlens shape production, and result in increased workload due to narrow pitch designs, causing variations in luminance and speckle noise, especially when using random distributions of microlens parameters.
Innovation Solution
A diffuser plate with a phase difference generation part between microlenses and the principal surface, featuring two or more types of lens shapes, where the quantity ratio and selection of lens shapes are optimized to achieve uniform diffuse light intensity within a specific angle range, reducing standard deviation and improving production efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single microlens array is used, then the device structure is simple, but variations in luminance and color occur due to diffraction spots
Solution Approach 1:
The patent combines two microlens arrays with different pitch values into a single integrated structure. The first microlens array has pitch P1 and the second has pitch P2 (where P1 ≠ P2), creating a composite microlens array that merges the optical functions of both arrays while suppressing diffraction spots and luminance variations through the pitch difference.
Solution Approach 2:
The patent creates a composite microlens array structure integrating two types of microlenses with different pitch characteristics. This composite structure functions as a unified optical element that leverages the complementary properties of both pitch values to achieve superior optical performance, including reduced luminance variation and suppressed diffraction effects.
2Reliability
If random distribution of microlens parameters is applied, then luminance variations are suppressed, but speckle noise increases and image quality degrades
Solution Approach 1:
The patent applies different pitch values to different regions or groups of microlenses within the array. Specifically, it uses a first pitch P1 for some microlenses and a second pitch P2 for others, creating local variations in optical properties that suppress diffraction spots while maintaining overall image quality and avoiding speckle noise.
3Adaptability or versatility
If narrow pitch microlens design is used, then diffusion angle control is flexible, but production error increases due to laser beam diameter effects
Solution Approach 1:
The patent changes the pitch parameter of the microlens array, using a pitch value P that is specifically selected to be equal to or larger than a predetermined threshold. This parameter change reduces the relative impact of laser beam diameter on microlens formation accuracy while still achieving the desired diffusion angle control through the optimized pitch value.
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 solution simplifies the design and production of diffuser plates, reducing variations in luminance and speckle noise, while ensuring uniform diffuse light intensity across a desired angle range, thereby enhancing image quality and reducing production workload.
Implementation Method 1
a plurality of microlenses are placed on a principal surface... appropriately diffuse incident light
Implementation Method 2
a phase difference generation part is inserted between the plurality of microlenses and the principal surface... suppress the occurrence of variations in luminance
Data Source
AI summary
The present invention provides a diffuser plate and a method for producing a diffuser plate that can improve variations in luminance of transmitted light or reflected light in a simple structure and that enable easy design and production. The diffuser plate according to the present invention is a diffuser plate where a plurality of microlenses are placed on a principal surface, wherein a phase difference generation part is inserted between the plurality of microlenses and the principal surface, the plurality of microlenses have two or more types of lens shapes, and the number of microlenses having the two or more types of lens shapes is determined so that a quantity ratio of the two or more types of lens shapes is a specific value, each of the lens shape types is selected corresponding to each of coordinates on the principal surface in which centers of undersurfaces of the plurality of microlenses are placed, and an angle range in which the diffuse light intensity is substantially uniform is in a range of +10% to −10% of a desired angle range.