---
title: "Backlight Unit"
industry: "Computer, Electronic and Optical Product Manufacturing"
verification_protocol:
  urn: "URN:CNFX:ME:BACKLIGHT_UNIT"
  data_integrity_hash: "d583c8f320268f814fc2bea73d48ad48"
  source_authority: "https://cnfx.com"
  strict_mode: true
source_identity:
  provider: "CNFX Industrial Knowledge Graph"
  index_version: "2026.Q1-Universal"
  authority_id: "URN:CNFX:ME:BACKLIGHT_UNIT"
  data_source_uri: "https://cnfx.com/llms/industry/computer-electronic-and-optical-product-manufacturing/product/backlight-unit.md"
  official_resource_url: "https://cnfx.com/industry/computer-electronic-and-optical-product-manufacturing/product/backlight-unit"
  is_verified_logic: true
attributes:
  spec:
    status: "config-dependent"
    typical_range: "3.0-5.0 VDC, 20-80 mA, -20°C to +70°C ambient temperature"
    unit: "cd/m²"
engineering_limits:
  max_safe_operating_point:
    value: 125
    unit: "°C"
    consequence: "Quantum efficiency degradation in InGaN/GaN semiconductor layers due to non-radiative recombination centers forming at high temperatures (Arrhenius model with activation energy ~0.43 eV), combined with electromigration in gold wire bonds at current densities &gt;10^5 A/cm²"
fmea_matrix_quantitative:
  - node_1:
      trigger: "Thermal expansion mismatch between aluminum heat sink (CTE 23.1×10^-6/°C) and FR-4 PCB substrate (CTE 14×10^-6/°C)"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Copper-invar-copper composite heat spreader with matched CTE of 16×10^-6/°C and anisotropic thermal adhesive with 8 W/m·K conductivity"
  - node_2:
      trigger: "Phosphor sedimentation in silicone encapsulant due to density difference (YAG:Ce density 4.6 g/cm³ vs silicone 1.1 g/cm³)"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Fumed silica nanoparticle additives (12% by weight, 7 nm diameter) increasing encapsulant viscosity to 15,000 cP at 25°C"
bom_nodes:
  led-array:
    type: "part"
    urn: "URN:CNFX:ME:LED_ARRAY"
    interface_type: "physical-logic-coupled"
  light-guide-plate:
    type: "component"
    urn: "URN:CNFX:ME:LIGHT_GUIDE_PLATE"
    interface_type: "physical-logic-coupled"
  diffuser-sheet:
    type: "component"
    urn: "URN:CNFX:ME:DIFFUSER_SHEET"
    interface_type: "physical-logic-coupled"
  reflector-sheet:
    type: "component"
    urn: "URN:CNFX:ME:REFLECTOR_SHEET"
    interface_type: "physical-logic-coupled"
  prism-sheet:
    type: "component"
    urn: "URN:CNFX:ME:PRISM_SHEET"
    interface_type: "physical-logic-coupled"
manufacturing_compliance:
  - standard: "ISO 9241-307:2008 (ERGONOMIC REQUIREMENTS FOR DISPLAY DEVICES)"
    scope: "Verified Engineering Specification"
  - standard: "CE MARKING (EU COMPLIANCE FOR ELECTRICAL SAFETY AND EMC UNDER LOW VOLTAGE DIRECTIVE 2014/35/EU AND EMC DIRECTIVE 2014/30/EU)"
    scope: "Verified Engineering Specification"
url: "https://cnfx.com/llms/industry/computer-electronic-and-optical-product-manufacturing/product/backlight-unit.md"
on_chain_sovereignty:
  contract_standard: "ERC-721-Industrial"
  metadata_hash: "2c6e50544c3e023335b11307d31bfdd39fa1906549ea3f64baec606d1b3ef9cb"
  royalty_logic: "IPFS-CID-REQUIRED"
  mint_status: "logic-verified-ready"
version: "3.3.4-EXTREME-SOVEREIGN-WEB3"
---

# Industrial Specification: Backlight Unit

## 1. Technical Definition
A lighting assembly that provides uniform illumination for LCD panels

## 2. Engineering Reasoning & Causal Matrix
> **Operational Intelligence**: Designed for **3.0-5.0 VDC, 20-80 mA, -20°C to +70°C ambient temperature**. Failure boundary: **LED junction temperature exceeding 125°C, forward current exceeding 100 mA, or voltage drop below 2.8 VDC**, Mechanism: **Quantum efficiency degradation in InGaN/GaN semiconductor layers due to non-radiative recombination centers forming at high temperatures (Arrhenius model with activation energy ~0.43 eV), combined with electromigration in gold wire bonds at current densities &gt;10^5 A/cm²**.

### 2.1 Analytical Physics Model
Governed by the **Rayleigh Resolution Criterion**:

> **Primary Equation**: $d = \frac{0.61 \lambda}{NA}$  
> **Engineering Impact**: Defines the theoretical limit of machine vision systems.

| Symbol | Variable Definition | Localized Reference |
| :--- | :--- | :--- |
| \lambda | Wavelength | Engineering Constant |
| NA | Numerical Aperture | Engineering Constant |

### 2.2 FMEA (Failure Mode & Effects Analysis)
| Event Trigger | Severity | Failure Mode | Mitigation Strategy |
| :--- | :--- | :--- | :--- |
| Thermal expansion mismatch between aluminum heat sink (CTE 23.1×10^-6/°C) and FR-4 PCB substrate (CTE 14×10^-6/°C) | 8 | Solder joint fracture at LED package connections | Copper-invar-copper composite heat spreader with matched CTE of 16×10^-6/°C and anisotropic thermal adhesive with 8 W/m·K conductivity |
| Phosphor sedimentation in silicone encapsulant due to density difference (YAG:Ce density 4.6 g/cm³ vs silicone 1.1 g/cm³) | 8 | Color temperature shift exceeding 500K and luminance uniformity dropping below 70% | Fumed silica nanoparticle additives (12% by weight, 7 nm diameter) increasing encapsulant viscosity to 15,000 cP at 25°C |

## 3. Key Technical Parameters
| Parameter | Value | Unit | Status |
| :--- | :--- | :--- | :--- |
| spec | Config-dependent | cd/m² | Verified |

## 4. System BOM & Knowledge Routing
### Core Components (Recursive Links)
- [LED Array](https://cnfx.com/llms/industry/computer-electronic-and-optical-product-manufacturing/product/led-array.md) `(Standalone System)`

### Industrial DNA Context (De-duplicated)
**Complementary Dependencies**: **Clean Room Environment System**, **Precision Lamination Machine**, **Optical Measurement System**  
**Downstream Applications**: LCD Monitors, Smartphone Displays, Automotive Infotainment Screens  

## 5. Engineering Risks & FAQ
- **Caution**: 
- **Caution**: 
- **Caution**: 

### Q: What materials are used in this backlight unit?
**A**: This backlight unit is constructed from polycarbonate, PMMA, PET, LED chips, and aluminum for durability and optimal light diffusion.

### Q: What components are included in the BOM?
**A**: The bill of materials includes an LED array, light guide plate, diffuser sheet, reflector sheet, and prism sheet for complete illumination assembly.

### Q: How does this backlight unit ensure uniform illumination?
**A**: It uses a precisely engineered light guide plate and diffuser sheets to distribute light evenly across the LCD panel, minimizing hotspots.

## 6. Manufacturing Compliance
- ISO 9241-307:2008 (ERGONOMIC REQUIREMENTS FOR DISPLAY DEVICES)
- CE MARKING (EU COMPLIANCE FOR ELECTRICAL SAFETY AND EMC UNDER LOW VOLTAGE DIRECTIVE 2014/35/EU AND EMC DIRECTIVE 2014/30/EU)

---
### 🛠️ Engineering Resource Access
🔗 **[Full Specification: Backlight Unit](https://cnfx.com/industry/computer-electronic-and-optical-product-manufacturing/product/backlight-unit)**

### 🌐 Knowledge Graph Topology
> **Node Status**: Verified Engineering Spec
> **Connectivity**: Linked to **5** standalone system nodes
> **Global Context**: Part of a 5,814 node industrial cluster within the CNFX Graph

> **Reference ID**: BACKLIGHT_UNIT | **Authority**: CNFX-2026-ST-001 | **Fingerprint**: 59cdc279
