Projection Lens Light Shielding Ring Rotation for Thermal Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing projector technologies suffer from image deterioration due to uneven temperature distribution in the lens barrel caused by the image forming panel being shifted relative to the optical axis, leading to lens deformation and optical performance changes.
Innovation Solution
A projection lens system with an annular light shielding member mounted rotatably on the lens barrel, which is driven by a rotation mechanism to uniformly distribute temperature across the lens barrel, preventing thermal deformation and maintaining image quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the image forming panel is shifted relative to the optical axis to improve projection geometry, then the screen can be disposed above the projector, but uneven temperature distribution occurs in the lens barrel causing lens deformation and image deterioration
Solution Approach 1:
The light shielding member is made rotatable about the optical axis, transforming a static component into a dynamic one. This rotation enables the system to adapt to the uneven temperature distribution by periodically changing which portions of the light shielding member are exposed to heat, preventing permanent thermal deformation and maintaining optical performance.
Solution Approach 2:
The light shielding member rotates periodically about the optical axis, creating a cyclic exposure pattern to thermal radiation. This periodic action distributes thermal energy more uniformly across the lens barrel over time, preventing localized overheating and the resulting lens deformation that would occur with a fixed shielding member.
2Measurement precision
If a stop is disposed in the vicinity of the light source to remove non-contributing rays, then image quality is improved, but the stop temperature remarkably increases affecting the lens barrel
Solution Approach 1:
The light shielding member acts as an intermediary between the heat-generating stop and the lens barrel. By positioning and rotating this shielding member, the system mediates thermal energy distribution, allowing the stop to perform its image quality function while preventing excessive heat transfer to the lens barrel that would cause deformation.
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 effectively suppresses image deterioration by uniformly heating the lens barrel, preventing lens tilt and displacement, thus maintaining the optical performance and quality of the projected image.
Implementation Method 1
rays, which are deviated in the direction in which the image forming panel is shifted from the center of the optical axis of the projection lens, pass through the lens. Therefore, it can be seen that the temperature increases at the position, at which the light passes, in the projection lens
Implementation Method 2
the temperature of the lens barrel holding the stop becomes higher than that in the related art
Data Source
AI summary
A projection lens includes: first to fifth lenses; a light shielding ring; an aperture stop; and a lens barrel. The light shielding ring is rotated in a circumferential direction of the lens barrel by a rotation mechanism. In a case where an image forming panel is shifted with respect to an optical axis of the projection lens, a part, through which the light passes, is biased in the projection lens, whereby temperature distribution occurs in the lens barrel in the direction perpendicular to the optical axis. The thermal deformation of the high temperature side of the lens barrel due to the temperature distribution is greater than that on the low temperature side. The respective lenses may be tilted due to thermal deformation. By rotating the light shielding ring through the rotation mechanism, the temperature increases uniformly in the circumferential direction of the light shielding ring.