Ink Displays: A Safer, Low-Blue Light Alternative for Eye Health and Sustainability

Ink Displays: A Safer, Low-Blue Light Alternative for Eye Health and Sustainability

Taipei, May 14 – E Ink, the global leader in ePaper technology, has shared results from a peer-reviewed study conducted in collaboration with researchers at the Harvard T.H. Chan School of Public Health. The research highlights the harmful effects of high-energy blue light emitted by traditional displays and contrasts these with the safer characteristics of E Ink ePaper screens.

Blue Light and Its Effects on Eye Health

According to data from Nielsen, adults now spend approximately 13 hours a day looking at digital screens. Long-term exposure to LCD and LED screens can subject the eyes to high levels of blue light, which may contribute to retinal stress and cell damage. Especially at night, this blue light exposure can reduce melatonin levels, disrupt sleep patterns, and interfere with the body's circadian rhythm.

The Harvard study revealed that displays emitting brighter and cooler-toned light caused significantly more oxidative stress to retinal cells than displays with warmer or no light. Importantly, ePaper displays without a front light emit no blue light at all, making them an eye-friendly alternative for extended reading or screen time.

Key Findings from the Study:

• Backlight and front light spectrum are major contributors to retinal cell stress.
• Blue light exposure stimulates the production of reactive oxygen species (ROS), which may lead to photo-oxidative damage over time.
• E Ink devices using ComfortGaze™ front light create up to three times less retinal stress than comparable LCD screens.
• Color temperature impacts eye strain, with LCDs—even in night mode—still producing more stress than E Ink’s optimized lighting.
• E Ink displays without any front light do not emit blue light and are considered the least harmful to the eyes.

Dr. Rick Rogers, lead researcher and imaging expert from Harvard’s Biomedical Imaging Lab, emphasized that the goal of the study was to measure actual biological responses to commercially available screens, not just theoretical exposure levels. Dr. Rogers is also affiliated with the Massachusetts Biomedical Research Institute.

Safer Displays in a Digital World

"Reducing screen time isn’t always feasible in today’s connected world," said Johnson Lee, Chairman of E Ink. "But not all screens are the same. As concerns grow among parents about children’s prolonged screen use, switching to eye-safe displays like ePaper can provide a healthier alternative without disconnecting from the digital ecosystem."

Unlike LCD panels, which rely on backlighting, E Ink screens mimic printed paper by reflecting ambient light. When used in low-light settings, front lights (such as those in E Ink ComfortGaze™) serve as gentle illumination similar to a reading lamp, rather than flooding the eyes with blue light.

The Advantage of ComfortGaze™

The study also evaluated multiple front light configurations—cool white LEDs, amber lights, and E Ink's proprietary ComfortGaze™. This light system is designed to minimize surface reflection and blue light output without creating the strong amber tones often associated with "night mode." It offers enhanced reading comfort with reduced risk to the eyes.

Notably, to reach the same level of retinal oxidative stress induced by LCDs in a “cool white” mode, a user would have to spend three times as long using a ComfortGaze-equipped E Ink display in “warm white” mode.

Even Safer Than Paper?

Interestingly, the research also found that non-front-lit E Ink displays may be safer than even traditional white paper, which often contains fluorescent brighteners that reflect more blue light. In contrast, E Ink displays contain no such agents, making them a truly eye-friendly reading solution.

Environmental Benefits: Beyond Eye Health

Beyond eye safety, E Ink continues to explore the environmental advantages of ePaper over LCDs and printed materials. The results are impressive:

• A bank with 125 branches switching to digital notebooks using ePaper technology could reduce the use of 16.5 million A4 sheets annually, saving approximately 1,100 tons of CO₂ emissions.
• Over 130 million eReaders have replaced paper books in the past five years. Assuming each reader downloads 10 books per year, this shift prevents tens of thousands of times more carbon emissions than printing or using LCD tablets.
• Approximately 600 million ePaper shelf labels (around 3 inches in size) have been deployed globally. If pricing is updated four times daily, the carbon emissions from paper labels would be 32,000 times higher than those from ePaper alternatives.
• Replacing a 10-inch LCD billboard with an ePaper version for five years can save 400 kWh of energy per unit.
• Solar-powered ePaper signs used in smart bus stops and public information displays offer a 100% renewable energy solution, supporting global efforts toward net-zero emissions.

Original source from: https://cn.eink.com/news/detail/harvard-study-shows-e-ink-epaper-is-three-times-healthier-for-your-eyes-than-lcd