Solid State Lighting with Blue Laser Diodes Robert Gatdula, Jared Murray, Avery Heizler, Meet Shah
supervised by Prof. Wei Jiang
LED bulbs have already gone to the mass-market and have
proven to be more efficient and affordable compared to
incandescent and fluorescent lighting. However, next-
generation lighting may truly dominate from a different
type of solid-state device -- the laser. Laser-based lighting
has the potential to be more efficient given the right safety
measures and proper circuitry.
Luxury car manufacturer BMW has already developed a
headlight prototype proving this technology in their i8
concept car, and Laser Phosphor-based Displays (LPDs)
have already been developed by Prysm, Inc for large display
platforms.
Our project focuses on the theory behind this type of
lighting as well as explains why it should shine over LED
technology.
ABSTRACT/INTRODUCTION: ______ STOKES SHIFT AND WHITE LIGHT GENERATION: ______
Blue light hits yellow phosphor
Yellow phosphor emits yellow light (Stokes Shift )
Unabsorbed blue light with yellow light give white
light
LED/LASER DIODE DRIVER: ______
Buck converter with a
current sense feedback
Free running oscillation
High side N-Fet with
Bootstrap gating
Adjustable load current
166kHz switching
frequency
Soft turn-on of LED
CIE 1931 COLOR SPACE & COLOR TEMPERATURE: _____
The image above is the light produced by a blue LED coated with yellow phosphor.
Data points on the CIE 1931 color space show that the color is around white with a color temperature somewhere
between 6000 and 10000. LUMINOUS EMITTANCE: ______
LASER-BASED vs. CONVENTIONAL LIGHTING: ______
Laser diodes have better stability at higher current than LEDs -- allows for
high power applications.
The intensity of light in lased diodes is higher than that of LEDs at
comparable power levels.
Laser diodes have a longer illumination distance
Image on the right shows laser-based lighting (left) compared to
incandescent lighting (right)
Phosphor coating
Blue Laser Diode
Reflected light
Beam scattering at the surface of the phosphor
White light (blue and yellow beams used for illustrative purposes)
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Lux vs. Current (13 cm away from source)
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Lens 1
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