Rear Projection Screen Prism Density and Light Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rear projection screens face limitations in light utilization efficiency, compatibility with different projector types, image uniformity, and hotspot generation due to integrated refractive and anti-light portions, and limited image quality improvement by the diffusion layer's positioning.
Innovation Solution
A rear projection screen design featuring a transparent substrate with protruding prism structures, a light absorbing film with spaced light absorbing structures, and a diffusion film in sequence from the projection side to the viewer side, where the prism structures are denser than the light absorbing structures, allowing independent functions and improved light management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the refractive portion and anti-light portion are integrated on the same prism structure, then the structure can be simplified, but light utilization efficiency decreases due to absorption by light absorbing material
Solution Approach 1:
The invention divides the integrated prism structure into separate components: a refractive portion (prism structures on transparent substrate) and an anti-light portion (light absorbing film with light absorbing structures). This segmentation allows each component to perform its function independently without the other interfering, thereby improving light utilization efficiency while maintaining structural clarity.
Solution Approach 2:
The light absorbing film is extracted as a separate layer from the prism structures. By taking out the light absorbing material from the integrated prism structure, the patent eliminates unnecessary absorption of projection light while maintaining the anti-light function for ambient light, thus resolving the contradiction between structural simplicity and light efficiency.
2Ease of operation
If the diffusion layer is placed facing the projector, then the projection beam can be homogenized, but image quality improvement is limited and hotspots may be generated
Solution Approach 1:
Instead of placing the diffusion layer facing the projector (conventional approach), the invention inverts the arrangement by positioning the diffusion layer (first diffusion film) facing the viewer side. This inversion allows the diffusion function to work in conjunction with the prism structures, improving image quality and eliminating hotspots while maintaining homogenization benefits.
3Ease of manufacture
If the prism structures and light absorbing structures have the same distribution density, then the structure is simpler to manufacture, but image uniformity deteriorates
Solution Approach 1:
The patent applies different distribution densities to different components: prism structures have a higher distribution density than light absorbing structures. This local differentiation in density optimizes the balance between light refraction and ambient light absorption, improving image uniformity while maintaining manufacturing feasibility through controlled variations in structure density.
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 design enhances light utilization efficiency, supports various projector architectures, improves image quality, and prevents hotspot generation by optimizing the placement of the diffusion layer and light absorbing structures, resulting in better luminance and image uniformity.
Implementation Method 1
The projection beam emitted by the projector is refracted and guided by the refractive portion of the prism structure
Implementation Method 2
The anti-light portion of the prism structure will absorb the majority of the external ambient light
Implementation Method 3
the diffusion layer of the projection screen can homogenize the projection beam incident on the projection screen
Data Source
AI summary
A rear projection screen includes a transparent substrate, a light absorbing film and a first diffusion film in sequence from a projection side to a viewer side. The transparent substrate includes a first surface and a second surface opposite to each other, the first surface faces the projection side, the second surface faces the viewer side, and the first surface is disposed with a plurality of prism structures protruding toward the projection side. The transparent substrate is located between the light absorbing film and the prism structures. The light absorbing film includes a plurality of light absorbing structures arranged at intervals from each other, and the distribution density of the prism structures is greater than that of the light absorbing structures. The light absorbing film is located between the first diffusion film and the transparent substrate. The rear projection screen through the above-mentioned design has a good image display quality.