5mm LED:
(Roithner-laser page)
Vf=2.65 If=20mA 3500-4500mcd Pd= 53mW high @ 20 mA, 20°
(from datasheet on the page):
Vf=2.65 If=20mA 2000-5000mcd Pd= 45mW(max) high @ 20 mA, 15-25°
The half-life of the optical output at 25℃ is over 3,000hrs at 20mA and 25C
luminous efficiency of 20 lm/W
The correlated color temperature for Rank B varies from 12,000K to infinity. For Rank P, it varies from 5,000K to 12,000K. For Rank Y, it varies from 3,000K to 5,000K.
For Rank O, it varies from 1,600K to 3,000K.
(compare to Nichia NSPW500BS 20° 9200mcd Vf=3.65 If=20mA Pd= 73mW)
http://www.procomp.com.tw/us/2_7_2_1.asp
Sumitomo + Procomp = Supra Opto Inc (joint venture)
Supra will begin mass production of the LEDs in March 2003.
Patent highlights
13 January 2004
The pick of this week's patent applications including a white LED based on zinc selenide.
• Title: Semiconductor light-emitting device
Applicant: Sumitomo Electric Industries, Ltd, Japan
International application number: WO 04/004018
Feb. 28, 2000
Sumitomo Electric has developed a new original white LED designed for use as backlights for liquid crystal displays in the rapidly growing field of cellular telephones and will begin mass-production this fall.
We succeeded in developing white LEDs utilizing ZnSe (zinc selenide) in 1999 and have since worked to commercialize this device....We are planning a monthly production of five million pieces beginning this fall while continuing to invest in new facilities and equipment....The green to red light emitted from the substrate is the result of a phenomenon peculiar to ZnSe, in which the small amount of dopant contained in the ZnSe substrate causes the absorbtion of short-wavelength light (blue light in the case of the ZnSe white LED element) and converts it to longer-wavelength green to red light emitted from the substrate, i.e., the so-called photoluminescence (PL) phenomenon.
http://www.sei.co.jp/news_e/press/00/00_01.html
Dec 2002
"Sumitomo Electric has teamed with Procomp to commercialize ZnSe white LEDs. The companies plan to establish a joint venture under the name Supra Opto Inc, with Procomp holding 60% ownership and Sumitomo the remainder.
Sumitomo developed ZnSe-based white LEDs about four years ago. The company's device is a homoepitaxial ZnSe blue LED grown on a ZnSe substrate, which simultaneously produces blue light from the active region and yellow emission from the substrate.
Sumitomo says that the ZnSe LED offers a number of advantages. In conventional white LEDs, the use of a phosphor makes packaging more complicated and reduces the overall efficiency of the device. The ZnSe substrate is conducting, allowing the use of top and bottom contacts, unlike GaN-on-sapphire devices. Also, the ZnSe LED operates at a low voltage of 2.7 V, and is highly resistant to static electrical discharge."
More of the article at:
http://www.compoundsemiconductor.net/articles/news/6/12/2/1
Photo:
http://www.sei.co.jp/RandD_e/electro/ele_e08.html
