Transcript Challenges of Using UV LEDs

Introduction
Purpose
• Introduce Lumex’s new line of QuasarBrite UV LEDs
Objective
• Overview of UV wavelengths and applications
• Review of UV LED challenges
• Introduce three new UV products from Lumex
Content
• 10 Pages
Learning Time
• 5 Minutes
Welcome to the Lumex UV LED Technology training module. This module will present a general overview of UV
wavelengths and applications for UV technology. This module will also illustrate how Lumex’s new family of
QuasarBrite UV LEDs is overcoming some of the challenges faced today in designing products with UV technology.
A pioneer in the design and manufacture of user-interface technology for over 30 years, Lumex is a leader in semicustom and custom LED and LCD display technology.
Ultraviolet Light
UV
Visible Light
Infrared
Wavelengths in nanometers (nm)
100nm 420nm
780nm
Ultraviolet light or UV light is invisible to the human eye. This is because UV wavelengths are too short for human
eyes to perceive. UV LEDs span the wavelength spectrum from 100 nanometers to 420 nanometers.
Despite the potential hazards of ultraviolet light which are evident in every day life, such as sun burn, the UV spectrum
is proving to have many beneficial effects in a multitude of areas. Not unlike how standard, visible LEDs have
impacted today’s marketplace, the advancement of UV LEDs is offering a wide range of advantages to a diverse
number of applications. This promising technology is moving the UV market segment into a whole new level of product
innovation and performance.
Spectrum of UV Light
UV
Visible Light
Infrared
Wavelengths in nanometers (nm)
100nm 420nm
UV C
Short Wave
100nm
UV B
Medium
Wave
780nm
UV A
Long Wave
280nm 315nm
420nm
Within the wavelength spectrum, the range of UV light can be broken into three primary areas. The Ultraviolet A, or
UV-A long wave, falls within the range of 315 nanometers to 420 nanometers. Ultraviolet B or, or UV-B medium wave,
is within the 280 nanometers to 315 nanometer range. And finally Ultraviolet C, or UV-C short wave, is with the 100
nanometers to 280 nanometer range.
Each area within the UV spectrum offers distinct benefits in industries ranging from medical to forensic science to test
and measurement.
Applications
Fingerprint ID on a
computer mouse
with UV light
Security check of US
currency under UV light
UV laser passing
through a cuvette
for DNA testing
UV machine varnish
Bacterium in a petri dish
fluorescing under UV light
230nm-400nm : optical sensors & instrumentation
300nm-320nm : Medical light therapy
230nm-280nm : UV ID verification, barcodes
300nm-365nm : Polymer and Ink printing
240nm-280nm : Sterilization of surface areas and water
375nm-395nm : Counterfeit detection
250nm-405nm : Forensic & bodily fluid detection & analysis
390nm-410nm : Superficial sterilization
270nm-300nm : Protein analysis, drug discovery
Spectrum range lists market applications typical for a particular range. However, product applications can extend to any use within the full UV spectrum.
Many applications in today’s marketplace are ideally suited for, and already utilizing, UV LED technology. Within the
UV spectrum, examples of such applications include counterfeit detection, bodily fluid detection and analysis, polymer
and ink printing, and medical light therapy and sterilization.
Advantages of UV LEDs vs. CFL
There has been a marked increase in the adoption of UV LEDs for applications that until recently relied upon
fluorescent UV lights. UV LEDs offer many benefits over traditional CFL UV lamps. For example, UV LEDs utilize
much less energy than their CFL counterparts. UV LEDs are RoHS compliant and they are not toxic if broken. In
addition, UV LEDs offer much smaller, more compact sizes than CFL lamps, and UV LEDs are much more resistant to
vibration and impact.
Challenges of Using UV LEDs –
Life Hours
0 hours
5,000 hours
Until recently, the challenge of using UV LEDs had been stabilizing the die at the wavelengths needed. Recent
advancements have overcome the stabilization of the die, but challenges still remain in the packaging of the die in an
effort to yield the same life hours as existing standard LED technology. Standard epoxy packages usually provide less
than 5,000 life hours because the UV rays break the epoxy down rapidly. ‘Hardened’ or ‘UV resistant’ epoxy packages
usually have less than 10,000 life hours, which is still not nearly enough for most applications and the epoxy break
down is erratic, not graceful or linear.
Challenges of Using UV LEDs Efficiency
1 Watt
Input
Power
0.15 Watt
Output
Power
One of the other major challenges of utilizing UV LEDs for any application is the efficiency rate. For many applications
such as medical light therapy, water sterilization and polymer curing at less than 365nm, the output power is only 58% of the input power. At 395nm and above the efficiency improves, but only to about 15%.
Lumex QuasarBrite™ UV LEDs
The new Lumex QuasarBrite UV LED family comes in three different wavelengths, 385nm, 405nm and 415nm. The
applications at 385nm include counterfeit detection, bacterial sterilization and ink fluorescing. At 405nm one of the key
applications is forensic analysis of bodily fluids. Finally, the 415nm UV LED can be used in superficial sterilization
including skin treatment. All three LEDs come in a robust TO-42 package with glass lens, which increases life hours
from 5,000 compared to an epoxy package up to a minimum of 50,000 hours.
Summary
•
UV LEDs are positively influencing today’s marketplace, offering a wide
range of advantages to a diverse number of applications.
•
UV LEDs offer many benefits over traditional UV lamps, such as energy
consumption, environmentally friendly, are more compact and offer
much more resistance to vibration and impact
•
Challenges still remain for utilizing UV LEDs in product design, such as
extended life hours and efficiency
•
Lumex’s new, innovative family of UV LEDs overcome the challenges of
other UV LEDs available on the market and offer design engineers
greater flexibility and efficiency
UV LEDs have impacted today’s marketplace, offering a wide range of advantages to a diverse number of
applications. UV LEDs offer many benefits over traditional UV lamps, such as energy consumption, environmentally
friendly are more compact and offer much more resistance to vibration and impact. However challenges still remain
such as extended life hours and power output efficiency. Lumex’s new QuasarBrite UV LEDs overcome these
challenges and has extended the use of UV LEDs in ways that might not have been considered for applications in the
past, such as counterfeit detection, forensic science and medical devices.