Understanding LED Illumination

Understanding LED Illumination

by M. Nisa Khan
Released August 2013
Publisher(s): CRC Press
ISBN: 9781000755756

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Book description

This book provides an in-depth introduction to the fundamentals and practical aspects of LED lamp design. Covering light generation, efficiency, theoretical limits, efficiency limiting factors, and LED lamp design elements, it explains the principles of large-space and 3D object illumination for developing competitive LED lamps. It presents design and simulation requirements for LED lamps with real examples that demonstrate how to make more energy-efficient and higher-quality lamps. This book also applies lamp output metrics and characterization methods to retail and prototype lamps for comparison.

Table of contents

  1. Cover
  2. Half Title
  3. Title Page
  4. Copyright Page
  5. Dedication
  6. Table of Contents
  7. Preface
  8. Acknowledgments
  9. About the Author
  10. 1. Introduction
    1. 1.1 Introduction
    2. 1.2 Lighting Fundamentals
      1. 1.2.1 A Very Brief History of the Study of Light
      2. 1.2.2 Introduction to Lighting Fundamentals
      3. 1.2.3 Quantitative Parameters of Lighting
        1. 1.2.3.1 Color Metrics
        2. 1.2.3.2 Luminance, Illuminance, and Spatial Light Distribution
        3. 1.2.3.3 Summary of Lighting Metrics Used by Engineers and Manufacturers
    3. 1.3 Lighting Technologies
      1. 1.3.1 Introduction
      2. 1.3.2 Fluorescent Lamps
        1. 1.3.2.1 Compact Fluorescent Lamps
        2. 1.3.2.2 Toxicity
        3. 1.3.2.3 High-Intensity Discharge Lamps
      3. 1.3.3 Incandescent Lamps
        1. 1.3.3.1 Halogen Lamps
        2. 1.3.3.2 Other Lighting Technologies
      4. 1.3.4 Light-Emitting Diode Lamps
    4. 1.4 Understanding Illumination
      1. 1.4.1 Lighting Parameters: A Deeper Look
      2. 1.4.2 Parameters Important for LED Lighting
      3. 1.4.3 Units of Measurement
    5. 1.5 Understanding Energy Efficiency
      1. 1.5.1 “Green” Energy Solutions
      2. 1.5.2 Luminous Efficacy versus Luminous Efficiency
      3. 1.5.3 Determining Maximum Efficacy
      4. 1.5.4 Efficiency of Light Sources
      5. 1.5.5 LED Luminaire Efficacy
    6. 1.6 The LED Industry: Current and Future Prospects
      1. 1.6.1 Worldwide Growth
      2. 1.6.2 High-Brightness LEDs
      3. 1.6.3 LED Applications
      4. 1.6.4 Challenges and Limitations for the LED Industry
  11. 2. LED Lighting Devices
    1. 2.1 Introduction
    2. 2.2 Basics in Semiconductor Optoelectronics
      1. 2.2.1 Light Emission in Semiconductors
      2. 2.2.2 LED—The Semiconductor Diode
      3. 2.2.3 LED Device Structure
      4. 2.2.4 White LED Configurations and Challenges
      5. 2.2.5 Blue LEDs’ Unique Challenges
      6. 2.2.6 Substrates for Nitride-Based LEDs
    3. 2.3 Compound Semiconductor Materials and Fabrication Challenges
      1. 2.3.1 Yield or Binning Effects for Costs
      2. 2.3.2 Manufacturing Automation
      3. 2.3.3 Standards Implementation
      4. 2.3.4 Chip Production and Inventory Management
      5. 2.3.5 Technology Advancements of Compound Semiconductors
        1. 2.3.5.1 LED Materials Science
      6. 2.3.6 Large-Scale Manufacturing Process Control
    4. 2.4 Determining and Improving LED Lighting Efficacy
      1. 2.4.1 Quantification of LED Efficiency and Efficacy
      2. 2.4.2 Determination of Phosphor Efficiency
      3. 2.4.3 Estimation of White LED Efficacy Limit
        1. 2.4.3.1 Theoretical Efficacy Limit
        2. 2.4.3.2 Practical Efficacy Limit
  12. 3. LED Module Manufacturing
    1. 3.1 Introduction
    2. 3.2 LED Lighting Components and Subsystems
      1. 3.2.1 Power-Based LED Module Configurations
      2. 3.2.2 LED Subsystem Configurations
        1. 3.2.2.1 Printed Circuit Board Subsystems
        2. 3.2.2.2 Chip-on-Board Subsystems
        3. 3.2.2.3 Electronic Drivers
    3. 3.3 Thermal Management and Lifetime Studies
      1. 3.3.1 Heat Transfer Mechanisms
      2. 3.3.2 LED Junction Temperature
      3. 3.3.3 Thermal Analysis and Modeling
        1. 3.3.3.1 Thermal Resistance
      4. 3.3.4 Thermal Simulation
        1. 3.3.4.1 Simulation Techniques
        2. 3.3.4.2 Incorporation of Thermal Measurements
      5. 3.3.5 Lifetime and Aging Studies
        1. 3.3.5.1 Defining LED Lamp Lifetime
        2. 3.3.5.2 Lumen Maintenance during Lifetime
    4. 3.4 Optimizing Module Designs for Manufacturing Platforms
      1. 3.4.1 Thermal Design Considerations
        1. 3.4.1.1 Module Heat Sink
        2. 3.4.1.2 Board Technologies
        3. 3.4.1.3 Extruded Heat Sink
        4. 3.4.1.4 Adhesive Materials
        5. 3.4.1.5 Utilizing Convection
        6. 3.4.1.6 Optimization of LED and Drive Current Quantities
        7. 3.4.1.7 Active Cooling
      2. 3.4.2 Optical Design Considerations
        1. 3.4.2.1 Light Extraction from LED Emitter
        2. 3.4.2.2 Shaping Light Distribution
        3. 3.4.2.3 Color Parameters
      3. 3.4.3 Electrical Design Considerations
        1. 3.4.3.1 Fabrication of Anode and Cathode Contacts
        2. 3.4.3.2 LED Arrangement Designs
        3. 3.4.3.3 Electrical Control Functions
      4. 3.4.4 Mechanical Design Considerations
  13. 4. Lamp Measurement and Characterization
    1. 4.1 Introduction
    2. 4.2 Measurement and Characterization of General Lighting Parameters
      1. 4.2.1 Primary Lighting Metrics and Measurements
      2. 4.2.2 Secondary Lighting Parameters
      3. 4.2.3 Conversion Methods for Radiometric and Photometric Quantities
        1. 4.2.3.1 Monochromatic Radiation
        2. 4.2.3.2 Polychromatic Radiation
      4. 4.2.4 General Photometric Measurements
        1. 4.2.4.1 Luminous Flux, Φ
        2. 4.2.4.2 Luminance, L
        3. 4.2.4.3 Illuminance, Ev
        4. 4.2.4.4 Luminous Exitance, M
        5. 4.2.4.5 Flux Distribution
        6. 4.2.4.6 Luminous Efficacy and Luminous Efficiency
      5. 4.2.5 General Colorimetric Measurements
        1. 4.2.5.1 The CIE Standard Illuminants
        2. 4.2.5.2 The CIE Standard Color Spaces
        3. 4.2.5.3 The CIE Standard Chromaticity Diagrams
    3. 4.3 Application of Standard Photometry and Colorimetry to LED Lamps
      1. 4.3.1 Lamp Measurements and Comparisons
        1. 4.3.1.1 Ambient Lamp Measurements
        2. 4.3.1.2 Task Lamp Measurements
      2. 4.3.2 Recommendations and Guidelines for LED Lighting Metrics
        1. 4.3.2.1 Specification Guidance for Retail Lamps
    4. 4.4 Measurement and Characterization of LED-Specific Semiconductor Lighting Properties
      1. 4.4.1 Optoelectronic Measurement and Characterization of LEDs
      2. 4.4.2 Lighting Parameter Characterization under Varying Thermal Conditions
      3. 4.4.3 Standard Activities for Photometric Measurements
  14. 5. LED Lamp Design Considerations
    1. 5.1 Introduction
    2. 5.2 Lighting Applications and Lamp Requirements
      1. 5.2.1 Ambient Lighting for Residential and Commercial Applications
      2. 5.2.2 Downlighting for Home and Commercial Applications
      3. 5.2.3 Large Space Lighting for Industrial Environments
      4. 5.2.4 Outdoor Lighting for Creating Visibility
      5. 5.2.5 Ultrahigh-Brightness Lighting from Confined Surfaces
    3. 5.3 Designs to Suit Lighting Applications
      1. 5.3.1 Lighting Quality Factors
        1. 5.3.1.1 Color
        2. 5.3.1.2 Brightness
        3. 5.3.1.3 Distribution
      2. 5.3.2 LED Lamp Design Considerations for Common Lighting Applications
        1. 5.3.2.1 Ambient Lighting Design Elements
        2. 5.3.2.2 Downlighting Design Elements
        3. 5.3.2.3 Large Space Lighting Design Elements
        4. 5.3.2.4 Outdoor Lighting Design Elements
        5. 5.3.2.5 Ultrahigh-Brightness Spot Lighting Design Elements
    4. 5.4 LED Lamp Design Parameters and Trade-offs
      1. 5.4.1 Trade-offs Specific to LED Lamps
      2. 5.4.2 LED Trade-off Study from Transient Data
      3. 5.4.3 LED Technology Improvement Roadmaps
  15. 6. LED Lighting Design and Simulation
    1. 6.1 Introduction
    2. 6.2 Simulation of LED Light Output
      1. 6.2.1 Lighting Simulation Basics of Packaged LEDs
      2. 6.2.2 Simulation of LED Luminous Intensity Distribution in Polar Coordinates
      3. 6.2.3 Simulating Detector Output as Observed in Practice
      4. 6.2.4 Simulation of Illumination Maps for Lighting Designers
    3. 6.3 Scaling Light Distribution over Large Spaces
      1. 6.3.1 Single- and Two-LED System Simulations
      2. 6.3.2 Two-LED System Simulations at Various Distances
      3. 6.3.3 Luminance Analysis with Varying Detector Size
      4. 6.3.4 Simulation Output Choices: Luminance or Incoherent Illumination
      5. 6.3.5 Summarizing the Nature of LED Illumination
    4. 6.4 Generating Uniform-, Multi-, and Omnidirectional LED Light Distribution
      1. 6.4.1 Application of Electromagnetic Theory to LED and Standard Lamps
      2. 6.4.2 Illumination Comparison of LEDs and Curved-Surface Lamps
      3. 6.4.3 Methods of Generating Multidirectional and Diffused LED Distribution
        1. 6.4.3.1 Uniform and Broadened LED Lamp Output Using Light Pipes and Compound Optical Elements
        2. 6.4.3.2 Uniform and Omnidirectional LED Lamp Output Using Tapered Waveguides
    5. 6.5 Experimental Verification of Expected LED Light Distribution Properties
      1. 6.5.1 Measurement and Comparison of Downlight Lamp Data
      2. 6.5.2 Measurement and Comparison of Ambient Lamp Data
      3. 6.5.3 Measurement and Comparison of 3-D Goniophotometric Lamp Data
  16. 7. LED Replacements for Incandescent and Linear-Tubular Fluorescent Lamps
    1. 7.1 Introduction
    2. 7.2 Household Lamp Comparisons and Replacement Considerations
      1. 7.2.1 Why Does the Edison Incandescent Lamp Remain Popular?
      2. 7.2.2 LED Replacement Opportunities for the Edison Lamp
      3. 7.2.3 Energy Savings Comparisons of LED, CFL, and Incandescent Lamps
    3. 7.3 Why Are Linear Fluorescent Lamps Popular in Commercial Buildings?
      1. 7.3.1 Features and Benefits of Linear Tubular Fluorescent Lamps
        1. 7.3.1.1 Energy Efficiency of Linear Tubular Fluorescent Lamps
    4. 7.4 Linear Tubular LED Replacement Lamp Developments
      1. 7.4.1 Department of Energy CALiPER Tests for Linear Tubular Lamps
      2. 7.4.2 A Novel LED Lamp Design for Replacing LFLs
        1. 7.4.2.1 Features and Benefits of the Novel LED Replacement Lamp
        2. 7.4.2.2 Overcoming Manufacturing Challenges for the Novel LED Lamp
    5. 7.5 Comparison of Measured Data from Various Tubular Lamps
      1. 7.5.1 Description of Tubular LED Replacement and LFL Luminaire Test Samples
        1. 7.5.1.1 Retrofitting LED Lamps into Existing Fluorescent Lamp Fixtures
      2. 7.5.2 Comparison of Illuminance Data for T8 Lamps
      3. 7.5.3 Comparison of Luminance Data for T8 Lamps
      4. 7.5.4 Comparison of Chromatic Data for T8 Lamps
      5. 7.5.5 Comparison of Goniophotometric Data for T8 Lamps
    6. 7.6 Conclusion
  17. References

Product information

  • Title: Understanding LED Illumination
  • Author(s): M. Nisa Khan
  • Release date: August 2013
  • Publisher(s): CRC Press
  • ISBN: 9781000755756