Blue light is the light closest to the UVA spectrum and includes all HEV (High Energy Visible) light. The blue light spectrum spans from 380 to 500 nm on the visible light spectrum. 

Natural blue light is essential for the body’s circadian rhythm as it is important for daytime alertness and mood. Too much blue light has been shown to have negative effects and cause symptoms such as eye strain, headaches, sleep disturbances, and macular degeneration (1234).

The light-emitting diodes (LED) have taken a natural part in our daily life, with less energy consumption as the main advantage. The downside of this technology is the high amounts of HEV (high energy visible) blue light emitted. LED is seen as one of the main contributors to symptoms caused by blue light.

Blue light has a direct connection to the body’s circadian rhythm, giving input to the brain via the surrounding light environment. This is done via specialized photoreceptors in the eyes constructed to react to blue light spectrum regulating the sleep hormone melatonin. Late-night exposure for blue light will disturb the body, which will regulate for a state of wakefulness instead of getting ready for sleep (123).


For the best effect, put the glasses on 45 to 60 minutes before bedtime, and make sure to turn the lights off before you put them on the bedside table. The blue-light-blocking effect will get reduced if unfiltered light reaches the eyes.

Consider setting a reminder on your phone to wear them at least an hour before your normal bedtime. Most people get good results wearing the glasses at least one hour before bedtime, and some of our customers have got even better effect extending the time to two or three hours.

This lens type is not suitable for use as sunglasses. The blue-light-blocking lenses filter out 99.5% of all blue light and have been developed specifically for sleep improvement. The lenses have been balanced to be as bright as possible, giving a clear and relaxed viewing experience. Sunglasses typically have noticeable darker lenses filtering out more light.

This lens type is not suitable for daytime or nighttime driving. The lenses filter out 99.5% of all blue light and have been developed specifically for sleep improvement. This gives a sunset-like color scheme, which affects the ability to differentiate traffic lights and reduces nighttime visibility.

Yes, you can use the blue-light-blocking glasses during the day. Many of our customers are enjoying the benefits of blocking blue light when working. Ensure the body gets enough blue light for its circadian rhythm regulation / daytime alertness by using the glasses exclusively for computer screen time.

To find a size and color that fits you well, we recommend looking at the given size reference and compare the measurements to your existing glasses.

We offer glasses in three categories: Narrow, Regular and Wide.

See our size guide here.


The orange color is connected to how effective the lenses are at filtering out blue light. Our custom-made orange lenses block out 99,5% of all blue light and a large amount of the green light spectrum, which is optimal for sleep improvement. Yellow or lighter colored lenses are not sufficient, as they fail to block out light between 460 and 480 nm.

The lenses filter out 99,5% of the blue and over 75% of the green light spectrum (See the grayed out area in the chart below). This includes the range of 460-480 nm that has been proven to have the most melatonin suppressing effect. 100% green light blocking lenses would become very dark red and interfere with the overall visibility, with negligible improvements in performance.  

THL Sleep graph second generation blue light blocking orange lens for sleep

The majority of our glasses come with lenses including premium anti-reflective/ anti-glare coatings to reduce glare and reflections. This ensures a combination of supreme optical clarity with a more relaxed viewing experience.

The lenses are made without a polarization filter, as this would interfere with polarized digital displays as a blackout effect would appear depending on the position. This blackout effect can be tested, rotating a pair of polarized sunglasses in front of another pair.

All our models have 100% UV protection. The lenses filter out all light up to 400 nm (UV400), which is verified according to industry standards.

We have left out the UV400 marking as it could potentially create confusion with a strong association with sunglasses. Sunglasses normally have a noticeably higher darkening effect that is more evenly distributed over the visible light spectrum.


Our warehouse is located in the US and we ship internationally to many countries.
For other countries, please check the availability to order from our store here.

Your order may be subject to import duties and taxes, which are levied once a shipment reaches your country. You are responsible for paying additional charges for customs clearance and for any duties or taxes applied to your package. Customs policies vary widely from country to country; please contact your local customs office for further information.

Please contact us immediately if you need to make any changes to your order. Once your package has shipped, we can’t make any further changes. All orders are processed quickly, and changes can only be made within 12 hours after an order has been placed.


We offer hassle-free 30-day returns for all U.S. orders. If you are not happy with the product for any reason, you can return it within this time period. All international (non-US) sales are final. Please refer to our full return policy for more information.

If you want to exchange a product within the return window, start by returning the item so that we can refund your order. Once this is done, place a new order for the item you want.

All of our products are covered by a 24–month limited warranty against manufacturing defects from the date of purchase. If any parts are defective when delivered, and it's our fault, we will replace your product for free.