KAIST develops skin-conforming LED mask that boosts elasticity by up to 4 times

A South Korean research team has demonstrated that an LED mask of its own design can improve skin whitening and boost elasticity by up to four times.

KAIST announced Wednesday that a joint research team led by Professor Lee Geon-jae of the Department of Materials Science and Engineering has confirmed skin-whitening and elasticity benefits using a face-conforming LED mask. The device combines a flexible, surface-emitting micro-LED array — which distributes light evenly across a broad area rather than in isolated points — with a three-dimensional elastic support structure whose individual sections move independently to conform to the varying contours of the face, including the nose, cheeks and chin.

Home beauty devices have grown increasingly popular as consumers seek convenient at-home skin care, but conventional rigid LED masks struggle to maintain simultaneous contact with both raised areas like the nose and recessed areas like the under-eye and cheek zones. Gaps between the LED and the skin increase light reflection, reducing the amount of light delivered to the skin, and can also raise the risk of low-temperature burns when heat becomes concentrated.

To address these shortcomings, the research team developed a surface-emitting LED mask that conforms to facial contours in 2024, demonstrating elasticity improvements of up to 340 percent over conventional LED masks. The latest research extended that work by verifying whitening effects in human subjects and examining the benefits of combining the mask with polynucleotide injections — widely used in dermatology for skin regeneration — on both elasticity improvement and post-procedure recovery.

The team irradiated the skin through the conforming mask using 630-nanometer red light, a wavelength absorbed by the skin to stimulate cellular activity. Treated areas showed significant improvements in brightness and tone uniformity compared with untreated areas, and improvements were recorded across five representative whitening indicators — including the amount of dead skin cells and the number and area of age spots. The effects were also confirmed in skin tissue samples obtained from human subjects.

The elasticity benefits were particularly pronounced when the mask was used alongside polynucleotide injections, a DNA-derived substance used for skin regeneration. When only the injection was applied to one side of the face, the deep-skin elasticity improvement rate was about 3 percent. When the injection was combined with the conforming LED mask on the other side, the rate rose to about 13 percent — roughly four times higher than with the injection alone.

The research team attributed the enhanced results to red light delivered through the conforming mask activating mitochondria — the energy-generating organelles within dermal cells — which increased production of ATP (adenosine triphosphate), the cell's primary energy source. This significantly amplified regenerative responses that the injection alone had been insufficient to trigger. Skin damage and inflammation caused by the micro-injection needles also subsided more quickly.

"This research clinically confirmed that a home-use LED mask can deliver not only skin regeneration but also whitening effects, and demonstrated the importance of close skin contact for effective light delivery," Lee said. "We plan to expand the face-conforming LED technology we have developed beyond cosmetic skin care into the field of home-care phototherapy."

The findings were published in the October issue of the international journal Nano Energy.