Radiation Detector Assembly Inner Encapsulation Layer

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Radiation detector assemblies with solid scintillators experience decreased sensitivity in high-temperature and high-humidity environments due to water molecules penetrating the optical adhesive, reducing bonding strength and transmission efficiency.

Innovation Solution

A radiation detector assembly with an inner encapsulation layer made of low water vapor transmission materials and an outer encapsulation layer formed by low-pressure chemical deposition, which seals the coupling portion between the scintillator and photosensor, preventing water molecule penetration and maintaining structural integrity under harsh conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If optical adhesive is used to couple scintillator and photosensor, then transmission efficiency of scintillation light is improved, but bonding strength is reduced in high-temperature and high-humidity environments

Engineering Contradiction:
Improvetransmission efficiencyVSAvoidbonding strength
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The encapsulation structure is divided into two distinct layers: an inner encapsulation layer in direct contact with the optical adhesive and coupling portion, and an outer encapsulation layer providing additional environmental protection. This segmentation allows each layer to perform its specific function optimally - the inner layer provides immediate barrier protection where water penetration is most critical, while the outer layer provides additional protection and structural support.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The inner encapsulation layer acts as an intermediary barrier between the harmful external environment (water molecules) and the optical adhesive-coupling portion interface. This intermediate protective layer prevents direct contact between water and the adhesive, maintaining both bonding strength and transmission efficiency in harsh environments.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Stability of the object's composition

If optical adhesive is used to secure scintillator and photosensor, then relative location is fixed, but water molecules penetrate adhesive in high-humidity environments causing separation

Engineering Contradiction:
Improverelative location stabilityVSAvoiddetector sensitivity
Core Design Contradiction:
Stability of the object's compositionVSReliability

Solution Approach 1:

The inner encapsulation layer is applied in advance to the coupling portion and light-exiting surface before the detector operates in high-humidity environments. This preliminary protective action creates a barrier that prevents water molecules from penetrating the optical adhesive during operation, thereby maintaining both the fixed relative location and the detector sensitivity throughout the operational period.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The encapsulation layers provide beforehand cushioning protection against the harmful effects of high-temperature and high-humidity environments. By pre-establishing this protective barrier, the optical adhesive is shielded from water penetration that would otherwise cause separation and sensitivity degradation over time.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

3Reliability

If encapsulation layers are added to prevent water penetration, then reliability in harsh environments is improved, but device complexity increases

Engineering Contradiction:
Improvestability in high-temperature and high-humidity environmentsVSAvoidstructure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The encapsulation layers are implemented as thin film structures that conformally coat the coupling portion and light-exiting surface. This approach provides comprehensive environmental protection while minimizing the added volume and structural complexity. The thin film nature allows the encapsulation to integrate seamlessly with the existing detector assembly without requiring significant structural modifications.

Inventive Principle:
Principle #30Flexible shells and thin films

4Reliability

If encapsulation is used to seal coupling portion, then water penetration is prevented, but manufacturing complexity increases

Engineering Contradiction:
Improveprotection from water penetrationVSAvoidmanufacturing process complexity
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The inner and outer encapsulation layers are nested concentrically, with the inner layer directly protecting the coupling portion and the outer layer providing additional protection. This nested structure allows for systematic manufacturing where each layer can be applied in sequence using established deposition techniques, making the manufacturing process manageable despite the additional protection layers.

Inventive Principle:
Principle #7Nested doll (Nesting)

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 enhances the reliability and service life of the radiation detector assembly by preventing water penetration, ensuring stable operation in high-temperature and high-humidity environments without increasing the detector's weight or affecting detection results.

Implementation Method 1

an outer encapsulation layer formed by low-pressure chemical deposition, which seals the coupling portion between the scintillator and photosensor

Methodology Applied
Scientific EffectChemical deposition: Chemical Vapour Deposition

Implementation Method 2

The optical adhesive has a higher optical refractive index and can reduce variation of the reflective index on an optical path from the scintillator to the photosensor, and thus improve the transmission efficiency of scintillation light

Methodology Applied
Scientific EffectRefraction: Refraction

Implementation Method 3

the scintillator absorbs the incident ray energy and converts the energy into scintillation light in equal proportion

Methodology Applied
Scientific EffectScintillation: Scintillation

Implementation Method 4

Flashing light is absorbed by the photosensor and converted into electrical signals

Methodology Applied
Scientific EffectPhotoelectric effect: Photoelectric Effect

Data Source

PatentEP3346294B1Radiation detector assembly and method of making the same
Publication Date: 2020.04.01 NUCTECH CO LTD
  • EP3346294B1 patent drawingFigure 1~2
  • EP3346294B1 patent drawingFigure 3~4
  • EP3346294B1 patent drawingFigure 5

AI summary

A radiation detector assembly and a method of manufacturing the same are provided. The radiation detector assembly includes a base and an outer encapsulation layer. The base includes a scintillator having a light-entering surface and a light-exiting surface on both ends thereof, respectively; a reflection layer provided on the light-entering surface and an outer peripheral surface of the scintillator; a photosensor comprising a photosensitive surface and an encapsulation housing, the photosensitive surface is coupled to the light-exiting surface via an optical adhesive; and an inner encapsulation layer adhered to an outer surface of the reflection layer and hermetically encapsulates a coupling portion where the scintillator and the photosensor connected with each other. the outer encapsulation layer is provided on the outer surface of the base.