Sealed Diffractive Optical Assembly for Laser Projection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing diffractive optical assemblies in laser projection units are vulnerable to moisture and contaminants, which can reduce diffraction efficiency and cause optical performance issues, especially in high-moisture environments.
Innovation Solution
A sealed diffractive optical assembly is designed with a sealing assembly comprising light-transparent first and second sealing plates and a spacer, enclosing the diffractive optical element in a closed cavity to protect it from environmental contaminants and maintain optical performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the diffractive optical element is exposed in air, then the structure is simpler and easier to manufacture, but the diffractive structure is vulnerable to moisture and dust contamination
Solution Approach 1:
The patent applies the inert environment principle by creating a sealed cavity around the diffractive optical element that excludes moisture and dust. The sealing assembly forms a protected internal environment where the diffractive structure can operate without contamination from external atmospheric factors, thereby maintaining reliability while allowing the element to be exposed in air during normal operation.
Solution Approach 2:
The patent employs a sealing assembly comprising sealing plates and sealing rings that form a protective enclosure around the diffractive optical element. This sealing structure creates a physical barrier that prevents moisture and dust from reaching the diffractive surface, solving the contradiction between ease of manufacture (open structure) and reliability (protected structure).
2Reliability
If the diffractive optical element is sealed in a cavity, then protection from moisture and dust is improved, but the device complexity increases
Solution Approach 1:
The sealing assembly uses sealing plates and sealing rings to create a protective cavity around the diffractive optical element. This approach provides reliable protection from moisture and dust while maintaining relatively simple construction, thus resolving the contradiction between reliability improvement and device complexity increase.
3Reliability
If the diffractive optical element is sealed in a cavity, then protection from moisture and dust is improved, but the manufacturing process becomes more complex
Solution Approach 1:
The patent creates a sealed cavity environment that protects the diffractive optical element from moisture and dust contamination. While this improves reliability, the sealing assembly adds manufacturing steps including positioning the diffractive element between sealing plates and bonding the sealing components, thereby increasing manufacturing complexity.
Solution Approach 2:
The sealing assembly comprising sealing plates and sealing rings provides protective enclosure but requires additional manufacturing steps for assembly and bonding, creating a trade-off between improved reliability and increased manufacturing 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 sealed assembly effectively prevents damage from moisture and contaminants, ensuring consistent optical performance and reliability of the laser projection unit in various environmental conditions.
Implementation Method 1
a spacer (626) spaced the first sealing plate (622) and the second sealing plate (624) apart. The first sealing plate (622), the second sealing plate (624), and the spacer (626) cooperatively define a closed receiving cavity (628)
Implementation Method 2
a diffractive structure (644) is formed on the diffractive body (642)... the diffractive optical element (64) is configured to diffract the laser collimated by the collimating element (50) so as to form the laser pattern
Data Source
Figure 1~2
Figure 3~4
Figure 5~7
AI summary
Disclosed are a diffractive optical assembly (60), a laser projection unit (100), a depth camera (400) and an electronic device (1000). The diffractive optical assembly (60) includes a sealing assembly (62) and a diffractive optical element (64). The sealing assembly (62) includes a first sealing plate (622), a second sealing plate (624), and a spacer (626). The first sealing plate (622) and the second sealing plate (624) are arranged opposite to each other. The spacers (626) spaces the first sealing plate (622) and the second sealing plate (624) apart. The first sealing plate (622), the second sealing plate (624) and the spacer (626) cooperatively defines a receiving cavity (628). The diffractive optical element (64) is accommodated in the receiving cavity (628). The diffractive optical element (64) includes a light transparent diffractive body (642) and a diffractive structure (644) formed on the diffractive body (642).