The Power Topled with lens (SFH 4258S/4259S) from OSRAM Opto Semiconductors has an 80% higher optical output than the standard version of the infra-red LED - despite the same surface area and the same current. This boost comes from a special thin-film chip which, thanks to Nanostack technology, has not just one but two p-n junctions that are grown one on top of the other. The resultant increased range will above all benefit applications in the security sector and in gesture recognition. The Power Topled is now available at distributor Rutronik.
Apart from the Nanostack chip and the associated higher output the new infrared Power Topled is the same as the standard version and can therefore be used as a simple direct replacement. The package dimensions (footprint) remain the same so existing designs can continue to be used. Because of the series circuit the voltage is higher by about factor 2. The infrared Power Topled produces an optical output of 80mW from an operating current of 70mA - around 80% higher than the standard model from the same current. The LED emits at a wavelength of 850nm and is therefore a good compromise between maximum spectral sensitivity for CCD and CMOS cameras and suppressed visibility for the human eye. It is available with beam angles of +/-15° (SFH 4258S) and +/-25° (SFH 4259S) from two different lens types.
