World’s smallest LED could turn your phone camera into a high-res microscope

Amazing stuff! Smartphones are getting smarter? Lab on a chip smartphone!

"... researchers from the Singapore-MIT Alliance for Research and Technology (SMART) who’ve developed the world’s smallest silicon light-emitting diode (LED) – at less than a micrometer wide – with an intensity comparable to much larger silicon LEDs. ...
Previous on-chip emitters have been difficult to integrate into standard complementary metal-oxide-semiconductor (CMOS) platforms. ...
Here, the researchers placed their tiny silicon LED in a 55 nm CMOS node alongside the other photonic and electronic components – all on one chip. ...
To test how their LED might be used in a real-world situation, they placed it into a lensless holographic microscope. Lensless microscopes are smaller than regular microscopes and less expensive because they don’t require complex, precise lens systems. ...

the researchers used a neural networking algorithm to reconstruct objects viewed by the holographic microscope. ...

The researchers found that their holographic lens provided more accurate high-resolution images than a regular optical microscope. ..."

From the abstract:

"A nanoscale on-chip light source with high intensity is desired for various applications in integrated photonics systems. However, it is challenging to realize such an emitter using materials and fabrication processes compatible with the standard integrated circuit technology. In this letter, we report an electrically driven Si light-emitting diode with sub-wavelength emission area fabricated in an open-foundry microelectronics complementary metal-oxide-semiconductor platform. The light-emitting diode emission spectrum is centered around 1100 nm and the emission area is smaller than 0.14 μm2 (~∅400

 nm). This light-emitting diode has high spatial intensity of >50 mW/cm2 which is comparable with state-of-the-art Si-based emitters with much larger emission areas. Due to sub-wavelength confinement, the emission exhibits a high degree of spatial coherence, which is demonstrated by incorporating the light-emitting diode into a compact lensless in-line holographic microscope. This centimeter-scale, all-silicon microscope utilizes a single emitter to simultaneously illuminate ~9.5 million pixels of a complementary metal-oxide-semiconductor imager."

World’s smallest LED could turn your phone camera into a high-res microscope Researchers have created the world’s smallest silicon LED and holographic microscope that opens up a wide range of potential applications, including turning your smartphone camera into a portable, high-resolution microscope.

SMART researchers create world’s smallest LED and holographic microscope that enable conversion of existing mobile phone cameras into high-resolution microscopes

A sub-wavelength Si LED integrated in a CMOS platform (open access)

Fig. 1: Device structure and emission spectra.