Companies like Samsung and LG have been increasingly relying on OLED display technologies for smartphones, digital cameras, and even TVs. These screens have incredible black levels and are super-thin, but the battery life promises of OLED technology have still never been completely realized. Add to that the high cost of making OLED panels, and you have the reason older LCD technology still dominates mobile devices. New work on OLEDs out of the University of Bonn could change that.

One of the main problems with OLED panels is that only about one-quarter of the electrical energy supplied to a standard OLED pixel actually goes to emitting light. Unlike LCD screens, the pixels themselves in OLED panels emit all the light we see. Energy efficiency can be improved to acceptable levels by adding materials like platinum and iridium to the matrix, but these add significantly to the cost.

The tweak made to OLEDs in the laboratory at the University of Bonn comes from a careful examination of the quantum-mechanical principles that form the basis of the screen technology. OLED panels are composed of organic molecules in a conductive and emissive layer sandwiched between an electrical anode and cathode. An electrical current is passed through the organic layers from cathode to anode. Thus, electrons are removed from the conductive layer providing an opening for electrons flowing from the emissive layer. Each time an electron fills in one of these so-called “electron holes,” it gives up energy in the form of light.

That’s the way it’s supposed to work, but there are more than positive and negative charges to be considered — the spin, or magnetic moment, of the particles is also of importance. Most of the charges produced by the current have the same spin and will repel each other, resulting in energy lost as heat instead of light. That’s why only a quarter of energy supplied to a naked OLED goes to generating light. In this new study, the researchers have developed an organic layer that increases the efficiency of OLEDs simply by waiting the electrons out.

The point of the expensive platinum layers in current OLEDs is to fiddle with the magnetic moment of the particles so more of them are converted to light, but this is only necessary if time is a factor. Traditional organic molecules can’t store electrical energy long enough for the spin to spontaneously flip, which it does eventually. The new organic molecules used in the study simply retain an electric charge for a longer time, allowing it to exploit the natural change in spin to generate light from more of the power supplied to the display.

Doing away with the platinum and iridium components of OLEDs could make the panels considerably cheaper and easier to manufacture. That could make a big difference to consumers — the screen on your smartphone often costs as much as the rest of the components combined. If you figure in the customary profit margin markup, the screen is a big chunk of the final cost. Maybe that won’t be the case forever, though.

Now read: UCLA creates flexible OLED display that can be stretched to double its normal size, folded in half

Research paper: doi: 10.1002/anie.201307601 -“Metal-Free OLED Triplet Emitters by Side-Stepping Kasha’s Rule”