Blue LED with no emission beyond 480 nm

[Steve]

I'm looking for an LED with no emission beyond (longer than) 480 nm.
It's best if it was eye-safe so as little UV emission as possible is
desired (> 400 nm ?). The few blue led's I've come across with peak
or dominant wavelengths of 430 nm have very wide spectra extending
beyond 480 nm.

 

[Don Klipstein]

I'm looking for an LED with no emission beyond (longer than) 480 nm.
It's best if it was eye-safe so as little UV emission as possible is
desired (> 400 nm ?). The few blue led's I've come across with peak
or dominant wavelengths of 430 nm have very wide spectra extending
beyond 480 nm.

You will either need a laser or need to filter the output of the LED.

Dichroic filters, including dielectric interference filters, work well.
Beware that their performance varies with angle of incidence. Other than
that, try a Wratten 47B - beware, it will eventually degrade with heavy
use.

Blue LEDs generally produce little enough UV for UV to not be the
limiting factor for eye safety. If you need severe UV removal, get a "UV
shield" stage lighting filter gel such as GAM 1510 or equivalent.

- Don Klipstein ([email protected])

 

[Don Klipstein]

You could try these leds listed under violet blue LEDs.

http://www.roithner-laser.com/LED_diverse.htm

Beware of epoxy body ones with peak wavelength 420 nm or less, or
dominant wavelength 430 nm or less. The shorter wavelengths in the
emission band (likely UV) cause epoxy around the LED chip to degrade
significantly in as little as several hundred or about 1,000 hours of use
at "rated current" or even the usual 20 mA "characterizing current".

Been there done that with some Uniroyal Optoelectronics devices with
peak wavelength 416 and 420 mA.

The 430 nm SiC blue LEDs tend to have rated dominant wavelength 466 nm.
I seem to think more like 460 or in the 450's since they appear a slightly
lavendarish whitish blue.

- Don Klipstein ([email protected])

 

[Steve]

I've seen references to such Uniroyal leds. Are they still being made
? If so, part number, distributor, etc ?

 

[Don Klipstein]

I've seen references to such Uniroyal leds. Are they still being made
? If so, part number, distributor, etc ?

I was referring to having the LEDs degrade significantly in several
hundred or around 1,000 hours - not successfully using them for anything.

IIRC, Uniroyal Optoelectronics went out of business quite a few years
ago.

They are possibly still avaiilable from LEDREPs:

https://www.ledreps.com/store/products/uoe2.htm

UVA-L3N30K-xx (3 mm size, 420 nm peak wavelength)

Datasheet for same wavelength 5 mm lamp:

https://www.ledreps.com/products/UOE/datasheet/UVA-L5N20K Data Sheet.pdf

LEDREPs has a 418 or 420 nm "violet" LED by Brite-LED Optoelectronics:

BL-LBVT5N18C

https://www.ledreps.com/store/products/brite-led/Default.htm

https://www.ledreps.com/store/products/brite-led/PDF/
BL-LBVT5N18C%20series%20datasheet.pdf (page not found)

- Don Klipstein ([email protected])

 

[Steve]

Thanks Don. The Brite-LED parts can also be ordered direclty from
Brite-LED in small quantity for a bit less cost than LEDREP.