application brief AB20 5
replaces AN
1149 5
Secondary Optics Design
Considerations for SuperFlux LEDs
Secondary optics are those optics which exist outside of the LED package, such as reflector
cavities, Fresnel lenses, and pillow lenses. Secondary optics are used to create the desired
appearance and beam pattern of the LED signal lamp.
The following section details the optical characteristics and optical model creation for Lumileds
SuperFlux LEDs. In addition, simple techniques to aid in the design of collimating reflectors,
collimating lenses, and pillow lenses are discussed.
Table of Contents
Optical Characteristics of SuperFlux LEDs
LED Light Output
SuperFlux LED Radiation Patterns
Optical Modeling of SuperFlux LEDs
Point Source Optical Model
Detailed Optical Models
Secondary Optics
Pillow Lens Design
Design Case—Pillow Design for an LED CHMSL
Non symmetric Pillow Lenses
Selecting the Size of the Pillow Optic
Recommended Pillow Lens Prescriptions
Other Diverging Optics
Reflector Design
Design Case—Reflector for a CHMSL Application
Reflector Cavities with Linear Profiles
Reflector Cavities with Square and Rectangular Exit Apertures
Other Reflector Design Techniques
Collimating Lens Design
Fresnel Lens Design
Design Case—Collimator Lens
Other Lens Design Options
Appendix 5A
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