Wavelength Converter Rotating Substrate Direct Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing projector technologies using phosphors as illuminators often suffer from inadequate cooling due to indirect heat transfer to cooling fins, leading to insufficient cooling of the phosphor surface.
Innovation Solution
A wavelength converter with a rotating substrate and fins on its surface, where air is introduced through a channel to directly cool the phosphor, utilizing centrifugal force to enhance airflow and increase cooling efficiency, and an optical part enclosure with a separate wall section to prevent stagnation and promote low-temperature air flow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If cooling fins are provided on the rear surface of the substrate to transfer heat away from the phosphor, then heat transfer capability is improved, but the cooling effectiveness of the phosphor surface deteriorates because the heat transfer path is too long and indirect
Solution Approach 1:
The cooling function is segmented into two independent systems: (1) rear surface cooling fins for heat transfer away from the substrate, and (2) front surface air introduction channels with openings for direct cooling of the phosphor surface. This segmentation allows each system to optimize its cooling path independently, with the front surface system providing direct cooling to where heat is generated, thereby resolving the contradiction between heat transfer capability and phosphor surface temperature control
Solution Approach 2:
Air acts as an intermediary cooling medium introduced through the air introduction channels and openings on the front surface. This intermediary directly contacts the phosphor surface to absorb heat at the source, rather than relying solely on conductive heat transfer through the substrate to the rear surface fins. The intermediary air flow bridges the gap between the phosphor surface and the cooling system, enabling effective surface cooling while maintaining the rear surface heat transfer path
2Temperature
If the opening of the air introduction channel is positioned directly over the wavelength conversion element, then direct cooling efficiency is improved, but centrifugal force cannot be effectively utilized to enhance airflow
Solution Approach 1:
The opening of the air introduction channel is positioned at a location with different functional requirements than the wavelength conversion element itself. The opening is placed in a region where centrifugal force can effectively drive air flow, while the wavelength conversion element remains in its optimal position for direct cooling. This local differentiation of function allows the system to simultaneously achieve effective air flow generation and direct cooling of the phosphor surface
Solution Approach 2:
The air introduction channel extends in the radial direction from the opening toward the wavelength conversion element, creating a three-dimensional cooling path. The opening is positioned radially inward from the wavelength conversion element, allowing air to be introduced and then accelerated by centrifugal force in the rotating frame to flow along the phosphor surface. This dimensional arrangement enables both centrifugal force utilization and direct cooling without requiring the opening to be directly over the phosphor
3Temperature
If the plurality of fins are positioned close to the wavelength conversion element, then cooling coverage is improved, but the space for effective air flow path is reduced
Solution Approach 1:
The cooling system is segmented into front surface cooling (via air introduction channels and openings) and rear surface cooling (via fins). The fins are positioned on the rear surface of the substrate, separated from the front surface wavelength conversion element by the substrate thickness. This segmentation allows the front surface to have sufficient area for air flow path and direct cooling, while the rear surface fins provide additional cooling coverage without competing for the same space, thereby resolving the contradiction between cooling coverage and air flow path area
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 cools the phosphor, ensuring bright and high-quality image projection by increasing airflow and reducing heat-related degradation, while also potentially reducing part costs by optimizing fin placement.
Implementation Method 1
When the plurality of fins rotate, resultant centrifugal force induces air flow directed from the center of rotation of the substrate toward the outer circumferential side thereof
Implementation Method 2
air introduced through the opening of the air introduction channel facing the first surface flows along the first surface and directly cools the wavelength conversion element provided on the first surface
Data Source
AI summary
A wavelength converter includes a rotating device, a substrate rotated by the rotating device, and a wavelength conversion element and a plurality of fins provided on a first surface of the substrate, and the first surface is so provided as to face an opening of an air introduction channel through which air for cooling the wavelength conversion element is introduced.