Visible LED alternatives for high-radiance applications

Eric H. Altendorf

doi:10.1117/12.475719

3 July 2003 Visible LED alternatives for high-radiance applications

Eric H. Altendorf

Proceedings Volume 4996, Light-Emitting Diodes: Research, Manufacturing, and Applications VII; (2003) https://doi.org/10.1117/12.475719
Event: Integrated Optoelectronics Devices, 2003, San Jose, CA, United States

Abstract

Laser diodes are used in high radiance applications, requiring spatially and angularly localized optical power, in order to minimize system size, cost, and power requirements. For applications requiring visible wavelengths (400nm to 700nm), AlInGaP laser diodes are utilized for wavelengths between 630nm and 650nm, and recently InGaN-based laser diodes spanning the violet to blue spectral range (400nm to 450nm) have become available, with longer wavelength devices being actively developed. It is not clear, however, when reliable laser diodes emitting in the green to yellow portion of the visible spectrum (>500nm) will be realized. In addition, single mode laser diodes required for high radiance applications typically exhibit speckle effects, are temperature sensitive, require non-linear drive electronics, and can be effected by optical feedback. High radiance LEDs with appropriate emitter dimensions can be used in place of laser diodes provided that moderate coherence and power levels are acceptable. This article examines the general dependencies of beam focusing, collimation, and coherence, on LED emitter size and radiance. Specific model examples are considered, using parameters consistent with typical laser diode collimating lenses. Edge emitting LEDs or EELEDs used for miniature scanned displays are described as high radiance LEDs suitable for other applications requiring collimation, partial coherence, or localized irradiance.

Citation Download Citation

Eric H. Altendorf "Visible LED alternatives for high-radiance applications", Proc. SPIE 4996, Light-Emitting Diodes: Research, Manufacturing, and Applications VII, (3 July 2003); https://doi.org/10.1117/12.475719

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available