Considering the constant evolution of technology these days and its role in our daily lives, it comes as no surprise that our well-being is also affected in one way or another. However, it has come to a point where the concerns we have now are virtually non-existent in the past, like health problems and lifestyle hazards.
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Fortunately, the advancement in technology also paves the way for devices that address these concerns in the best way possible. Such is the case for sleep disorders, and the device that could help solve it best – light therapy glasses. Light therapy glasses have become famous for one main reason, they work!
- What Is Light Therapy?
- The Battle of Top Brands: Pegasi 2 vs. Luminette 3 Review
- 1. Pegasi 2 Smart Light Therapy Glasses
- 2. Luminette 3 Light Therapy Glasses
- Other Recommendations
- 3. AYO Light Therapy Glasses
- 4. Re-Timer Light Therapy Glasses
- 5. Propeaq Premium Light Glasses
- 6. Airblasters Timer Plus Light Therapy Glasses
- What Are the Benefits of Light Therapy Glasses?
- How Much Do Light Therapy Glasses Cost?
- Light Boxes vs. Light Glasses
- What Are Some Conditions That Respond to Light Therapy?
- Why We Would Recommend Light Therapy Glasses When being, i.e., sad
- Why Adding Sound Therapy to Light Therapy Glasses Could Work for you to Improve Sleep.
- What are the Cautions and Side Effects of Bright Light Therapy?
- How Do You Choose the Best Light Therapy Glasses?
- Frequently Asked Questions on Bright Light Therapy
What Is Light Therapy?
Light therapy, also called phototherapy, uses light in treating a broad range of health and medical conditions. It is beneficial in treating problems that suffice when the internal circadian rhythm is misaligned to natural light and darkness patterns. This may impact your ability to sleep and release hormones such as melatonin, energy levels, and mood.
The light therapy might be accomplished by timing exposure to the morning sunlight. Unfortunately, this may be difficult for people living in the northern latitudes, especially during the winter months. In such cases, you may need an artificial light source, and certain medical conditions respond greatly to this treatment.
How can light therapy glasses help me?
If you've been on the fence about getting help for your difficulties in sleeping, you've probably thought this question a lot to yourself. "How can light therapy glasses help me?"
These glasses are meticulously designed to benefit the user from light therapy or phototherapy. As the name suggests, light therapy is the scientific use of light to treat a medical condition. But, most of the time, it is used to address problems when a person's internal circadian rhythm is not aligned with the natural patterns of light and darkness.
You would likely fall into the category of people who could benefit greatly from light therapy glasses if you exhibit mood disorder symptoms, difficulties in sleeping, and jet lag. They also work for those on shifting schedules at work, who are often exposed to the light from computer or laptop screens and mobile devices, and those who live in the northern hemisphere, where days are usually longer than nights. Do not be surprised by what aids there are for everything – take hair loss as an example. We wrote a long piece on "Hair Growth Systems," which can help people regenerate their hair.
When Should I Wear Light Therapy Glasses?
Guidelines will vary from manufacturer to manufacturer, and each glass has different optical properties. However, for a general rule, if you need to optimize your sleep using light therapy, you wear them first thing in the morning for about 20 to 30 minutes to stimulate the rising sun. Notably, a lot of people use light therapy for their energy properties. In such cases, you should use your device during the morning, midday or after lunchtime, and this is to counteract the post-prandial circadian slump.
The Battle of Top Brands: Pegasi 2 vs. Luminette 3 Review
Two of the most highly talked about light therapy glasses today are Pegasi and Luminette. These two companies have been in the industry for so long that thousands of consumers have benefitted from their patented technology.
But for those who are just finding their way through the world of light therapy glasses, here are reviews of the two products that could help you make your mind on which product to get.
1. Pegasi 2 Smart Light Therapy Glasses
- 【SPECIAL BLUE-GREEN LIGHT】PEGASI II features the wavelengths of...
- 【SOLVE YOUR SLEEP PROBLEMS】PEGASI Smart Sleep Glasses II can help...
- 【EASY TO USE】Drug-free.You only need to wear PEGASI light therapy...
- 【SAFE FOR YOUR EYES】PEGASI is a member of the US National Sleep...
- 【Traveling Case Included】Upgraded 2.0 Version with new Carrying...
Pegasi 2 boasts research-backed technology that uses green and blue light to treat sleep problems without compromising comfort. The wavelengths between green and blue light are seen to be as equally effective as 10,000 lux white light, and you can choose from the three intensity levels.
It has a user-friendly design with an ultra-comfortable soft nose rest and a smart touch soft button, and it's a universal fit design with an adjustable size. In addition, the new generation light therapy device comes with features such as Bluetooth 4.0 connectivity and a patented flat LED panel. This means it will easily connect to your smartphone, and you can monitor the desired intensity and battery levels just from the smartphone app.
Its benefits are lumped in three main categories – improving sleep, boosting energy, and beating jet lag – with claims of significant changes showing just after 7 days of use. In addition, when not in use, it can double up as fashion wear, and the glass automatically switches off after each session of about 20 to 45 minutes.
Product Variants: This particular version of the Pegasi glasses is available in two variants – black and white. Both colors look classy and elegant no matter where you wear them to.
2. Luminette 3 Light Therapy Glasses
- ON-THE-GO LIGHT THERAPY - Enjoy more sessions anywhere you go with...
- PROVEN RESULTS – These portable glasses emit a blue-enriched white...
- COMFORTABLE & LIGHTWEIGHT - Luminette 3 wearable light therapy glasses...
- VERSATILE DESIGN - The Luminette 3’s patented illumination system...
- SAFE & CERTIFIED - Enjoy peace of mind knowing Luminette has been...
Luminette 3 is the newest model from this Belgian brand that has catered to over 70,000 users since 2006 and has 8 LED lights angled downwards. It comes with a slimmer design than its predecessor, a lighter frame, and a more convenient on/off button with the same level of effectiveness, and the glass itself fits perfectly on your face with the adjustable silicone nose piece.
It uses blue-enriched white light in three various intensities, which, studies show, is more beneficial than a 10,000-lux lamp. You can choose from three intensities 500, 1000 and 1500 lux, and it's pretty intense even at the lightest setting, especially if you are pretty new to it, and you should work your way up starting with the lowest setting. In addition, with its patented optical technology, the Luminette 3 ensures that the beam of light comes from a top-down angle that mirrors how natural light falls on the eyes.
It helps regulate your sleep patterns, keeps you energized in the morning, and can help you if you travel a lot in different time zones. However, you may find it challenging to wear them when going about your office work or household chores, especially in a dim room, but you eventually get used to it. Notably, if you are struggling to see, increase the brightness of your laptop screen or the lights in the room. A great tip would be to simultaneously use a modern rocking chair for the ultimate experience.
Product Variants: The Luminette 3 is only available in white.
3. AYO Light Therapy Glasses
- ✔ POWERFUL ENERGIZER - Meet AYO, premium light therapy glasses...
- ✔ ALL NATURAL SLEEP IMPROVEMENT LIGHT - AYO’s sleeping aid light...
- ✔ JET LAG PREVENTION - This compact light therapy solution allows...
- ✔ INNOVATIVE AND AWARD-WINNING TECHNOLOGY - The AYO wearable fits...
- ✔ PROVEN, SAFE, AND CERTIFIED – The AYO LED light glasses are a...
Known as one of the best-selling light therapy glasses on Amazon, AYO Light Therapy Glasses have cemented its place in the market as a trusted brand by consumers. The award-winning AYO Light Therapy Glasses are ergonomically designed to provide gentle exposure to a blue-turquoise light without affecting their lifestyle. It is designed more like a headband, and it's light (1.1 ounces) that it almost feels nothing when worn; hence can be worn over eyewear or sunglasses and will still give a stunning look.
AYO premium light glasses are Bluetooth compatible, and you can change most settings through the GoAyo app, and it fits comfortably on your face with no button on the slim frame. The glasses include a capsule-shaped travel case that doubles up as the charger, and it has a relaxed look and charges the unit entirely in about an hour and a half. The glass emits a blue wavelength of 475nm, and it's soothing and is made as an effective medical device that helps in boosting energy and regulating sleep patterns.
You can only use a smartphone to control it, and it's a disadvantage when your smartphone is drained, and you need an urgent boost of light therapy. However, it's also a positive as it minimizes the risk of soft buttons getting damaged because of frequent use.
Product Variants: The AYO Light Therapy Glasses are only available in white with blue side trimmings.
4. Re-Timer Light Therapy Glasses
- LIGHT THERAPY ON THE GO: Re-Timer was designed for active people whom...
- SAFE GREEN LIGHT: The most effective wavelengths of light are Blue and...
- WORLD’S BEST SELLING GLASSES: Available in 46 countries, Re-Timer is...
- EQUIVALENT TO A 10,000-LUX LAMP: Six published clinical trials...
REe-Timer and Luminette 2 therapy glasses were launched at roughly the same time, and the glasses have been pitted against each other, which is for a good reason. This is because they came with identical features, and they even shared identical price tags until Luminette dropped its price recently.
Re-timer is very popular with people with seasonal affective disorder (SAD), and it sold in 46 countries and are often advertised as the 'Gold Standard' in light therapy. This is because it packs a better build quality, is comfortable to wear, and is easy to adjust to your fit as it has a soft nose piece, and it can also be worn over any existing eyewear and perform routine tasks with the light switched on.
Re-timer light glasses have only two light settings, 300 Lux and 500 Lux and therefore, after weight the bright light exposure glasses for a few months, you might find the light emitted weak because your body has adjusted to it. Also, the light intensity at its highest is more of a green wavelength than a white one, and there's also a hint of blue, but according to most research, it favors the green.
Re-timer glasses are super effective for people who have irregular work hours, such as night-shift workers, as it helps to retime the circadian system body clock and regulate your sleep schedules. In addition, these glasses are suitable for you if you struggle with sleep due to insomnia, stress or nocturnal hypoxemia after an illness or injury.
Product Variants: The Re-Timer Light Therapy Glasses are only available in white.
5. Propeaq Premium Light Glasses
- The Propeaq light glasses are designed in collaboration with...
- The glasses feature integrated LEDs that provide blue light.
- This specific blue light suppresses the production of the hormone...
- Boost your energy, just like a power nap and fight fatigue
- The Propeaq glasses are used to chase away the winter blues, help with...
Propeaq Premium Light Glasses is the best portable bright light therapy option for anyone looking to optimize their productivity, performance and biohacking. It features an active blue light with LEDs function such as an extra sunrise for your senses, and this helps the user's body react by increasing the production of the cortisol hormone. In addition, it has interchangeable lenses, which you can swap to quickly when you are getting ready to sleep, and the orange lenses work by blocking the blue light to start a high production of the night hormone melatonin.
Propeaq can be used for half an hour to get maximum effects, and the glasses will conveniently turn off after 30 minutes. The glasses use a patented technology with a wavelength of 468 nanometers at a light intensity of 35 lux, and the bright light LEDs are distanced at over 1.5cm from the eyes and are safe to use every day. In addition, to get the most out of these glasses, the Propeaq ShiftWork app allows a user to set personalized schedules with clear usage instructions.
Propeaq Premium Light Glasses are suitable for irregular shift works such as night shift work, and they help workers get more energy levels, mood, health and alertness. In addition, they are also suitable for people with seasonal affective disorder, for athletes or anyone who wishes to wear glasses to boost their energy levels and get peak performance.
Product Variants: The Propeaq Premium Glasses are only available in white.
6. Airblasters Timer Plus Light Therapy Glasses
- Boost Energy-Blue Light-visible 470nm
- Blue light boosts alertness, helps memory and cognitive function and...
- Exposure to blue,light during daytime hours helps maintain a healthful...
- One year warranty Free return in 3 weeks withe money back
Airblasters Timer Plus Light Therapy Glasses are slightly better than the above light glasses because they include a feature not present in all the therapy glasses. They feature the ability to switch between blue light and red light. Studies have shown that red light is more suitable for evening use because of the low color temperature, which is lower than regular sunlight than the contrast feeling of blue light. A user can enjoy the red light in the evening without pushing your body and changing your internal body clock as a blue light does, which may contribute to sleep deprivation every night.
In addition, Airblasters Timer Plus Light Therapy Glasses, thanks to the blue light, boost a user's alertness, helps in memory and also cognitive function, and regulate the circadian rhythm, hence giving a user's body the natural sleep-wake cycle. Conversely, switching to the red light allows the body to ease into its sleep-wake cycle easier, and you can sleep better.
In addition, these light glasses help to minimize visual fatigue and discomfort over long periods of gaming, working under fluorescent lights or surfing. The light sensitivity glasses also include UV400 protection and glare reduction to maximize the benefits you will get from this pair.
However, these glasses have a significant design flaw. According to most user reviews, they will not be the most comfortable to wear as they are made of a cheap design and an impaired quality where they even break during the shipping process. Luckily, the manufacturer will send out replacements easily if a user has a good reason.
Product Variants: The Airblasters Timer Plus Light Glasses are only available in black.
What Are the Benefits of Light Therapy Glasses?
Fortunately, light therapy is now accessible even without going to hospitals or a specialist's clinic regularly. With the help of light therapy glasses, people have a more convenient way to work on their difficulties within the comforts of their homes or even wherever they prefer.
Light therapy glasses can improve sleep quality, improve one's mood, treat winter blues, and fight jet lag with regular use. In addition, users attest that light therapy glasses have shown positive effects in addressing their difficulty falling asleep, difficulty waking up, lack of deep restorative sleep, and lack of energy brought about by poor sleep quality.
On a greater scale, users of therapy glasses also enjoy other benefits such as improved mood and more alert brain function, which are also often associated with good sleeping habits. We recommend this excellent research paper on the benefit of light therapy glasses.
How Much Do Light Therapy Glasses Cost?
A quality brand of light therapy glasses may cost a couple of hundred dollars to as much as $300.
Although the price may seem a bit too steep to some, avid users of the device agree that it is worth the investment, especially if it manages to address sleeping problems that could eventually take a toll on one's health if left untreated.
For others who are not willing to spend a lot of money on light therapy glasses, though, some options go as low as $75 with pretty much the same benefits as the pricier ones.
Light Boxes vs. Light Glasses
Clinical bright light therapy for the seasonal affective disorder (SAD) has been around since the 1980s, but the standard treatment method of using a lamp type called light-box has not been updated in all these years. A light-box is a bright white light source that outputs at least 10,000 lux units at a specific distance.
The method is to sit in front of the light-box as soon as you wake up for about 30 minutes, and while there are significant benefits to the traditional light-box treatment, there are also some pretty obvious drawbacks. They include having to sit still in the morning while most people are rushing around trying to get ready for a busy day, and also you need to sit at a distance because the light source is very bright and intrusive by nature.
On the other hand, light therapy glasses are small and portable, and you can still boost energy in the morning while getting dressed, brushing your teeth, having breakfast and even working out. This is because these glasses are worn close to the eye, and the brightness of the light source can be somehow dim compared to a standard light-box. This means it's more discreet and won't blind anyone you are talking to, but you will still get the benefits you would get from sitting in front of the bright light-box.
- Large and bulky in terms of size
- For luminosity, 10,000 lux at 30 cm
- For positioning, you need the correct angle and at the required distance
- For power requirements, it is generally powered by main power only
- When it comes to the light color spectrum, it features a full-spectrum white light
- For smart features, it has none apart from maybe a timer
Light Therapy Glasses
- Ultra-light and small in terms of size
- For luminosity, 35-40 lux at eye level, equivalent to 10,000 lux white light-box at 30 cm.
- For positioning, you will need to wear and forget.
- For power requirements, you need a long battery life of up to a week
- For light color spectrum, it has a blue-enriched white light or a monochromatic blue or green light
- When it comes to smart features, it has advanced app functionality
What Are Some Conditions That Respond to Light Therapy?
Circadian rhythms of the body are affected by bright light therapy, and the part of the light spectrum works in full-spectrum sunlight. Notably, it can also be isolated and delivered at a lower light intensity, and it will still have equivalent effectiveness. Certain conditions will respond best to light therapy when delivered through light glasses, and they include:
a). Seasonal Affective Disorder (SAD)
Seasonal Affective Disorder (SAD), also called winter depression, occurs when there is a lack of light exposure, leading to a deterioration of your mood and energy levels. It could be associated with social isolation, changes in appetite, weight gain, lack of initiative and increased sleeping. In addition, it can be used for treating seasonal and nonseasonal depression, especially during the winter months in places with low light.
If you struggle and have difficulty falling asleep, bright light therapy might help you fall asleep faster and better. In addition, if artificial light exposure in the evening is an issue, you should use light glasses when you wake up in the morning, as this may help realign your circadian rhythms.
c). Morning Sleepiness
If you struggle with getting out of bed in the morning because of sleepiness, then bright light therapy might be for you. Light will naturally wake us up as it initiates the circadian alerting signal. So using it consistently in the morning may help align the sleep-wake cycle and get sleep's place to the darkness of the night.
d). Delayed Sleep Phase Disorder
Night owls usually experience the delayed sleep phase syndrome. It may lead to difficulty falling asleep at the appropriate time and difficulty waking up early in the morning. The bedtime for people with the delayed sleep phase disorder may be at around 2 pm or later, and they may wake up at around mid-morning or midday. Even though this syndrome is not associated with insomnia, it can be related to social pressures that may need the human body to wake up at times inconsistent with the normal.
e). Jet Lag
In today's world, jet travel allows the misalignment of the body's circadian rhythms to the patterns of darkness and light in the environment, and it may take a day to adjust to each time zone you cross. Light therapy makes adjusting occur quicker, and these light therapy glasses usually list this as one of the uses. However, note that this is not backed up with scientific evidence yet as a review of the studies has not yet found significant effects.
f). Energy boost
If you work with a dim light or in a dimly-lit environment, you will be generally tired during the day, and these glasses are a suitable and safe way of giving you an immediate energy boost. When you are having the afternoon slump, wear these glasses, and they will stimulate the natural effects of bright sunlight, giving you a needed energy boost. Light therapy is an alternative to taking a sleep med at night, overdosing on coffee, consuming a Redbull and taking a nap to give you an energy boost.
g). Shift Work
Shift work, done by night shift workers, is one of the primary uses of these glasses as shift workers may find it difficult for their body clock to fit the schedules that often change and rotate from days to nights. Research shows that bright light therapy and other methods such as melatonin supplementation can be a great strategy to help night-shift workers adapt to their schedules quickly.
Why We Would Recommend Light Therapy Glasses When being, i.e., sad
Light therapy glasses are highly recommended for people suffering from the effects of a messed-up body clock. Although it doesn't seem to be as big of a deal to some when they experience difficulties sleeping or constantly notice depleted energy, it wreaks havoc on their overall health.
Consistent use of light therapy glasses has proven beneficial in correcting the internal circadian rhythm and helping you recover energy, especially in the morning. But aside from helping you enjoy a restful sleep, the effects of light therapy glasses also extend to your ability to perform daily tasks with ease.
Moreover, it can be incredibly beneficial for people who have shifting schedules at work, those who live in the northern hemisphere, and those who often travel to different time zones. Combine these with a weighted blanket, and you will probably see results quickly.
Why Adding Sound Therapy to Light Therapy Glasses Could Work for you to Improve Sleep.
While light therapy is already effective with specialized glasses, the inclusion of sound therapy could also work wonders for users.
Also known as vibrational medicine or sound healing, sound therapy is a great way to relax and further stimulate healing.
If you have been using light therapy glasses for quite a while and have yet to see significant improvement in your sleeping patterns and energy levels, consider adding sound therapy to your home treatment to improve your body's reaction to therapy.
However, remember that while light therapy glasses and sound therapy are generally well-accepted, it is still best to consult specialists and discontinue use if there is any form of discomfort.
What are the Cautions and Side Effects of Bright Light Therapy?
Generally, phototherapy is well tolerated by most users, but if it's not, it should be discontinued. Any perceived side effects should be resolved once you stop using the light glasses.
Importantly, there isn't ultraviolet (UV) light exposure while using these light glasses, and therefore there are no risks associated with this, such as eye damage or cancer. However, some cases may have some short term side effects such as:
Seeing the light at the wrong time might cause sleep deprivation, like using light glasses during bedtime may cause a shift in the sleeping time to later. This might contribute to the circadian rhythm sleep disorders making it hard to fall asleep and wake up. You should avoid this by using the light glasses according to the instructions that come with the program.
Even though it's rare, fatigue may occur with phototherapy, which can have a lot to do with changes in the sleep-wake cycle. Ensure you use the bright light therapy as directed with the program to minimize the risk.
Artificial light therapy may trigger some migraines or headaches in those predisposed, and in such cases, it may be helpful to use the low light intensity for prolonged periods.
Blue light therapy may cause some sensitivity to light, and this may cause pain or an aversion to bright light exposure and is characterized by squinting. However, the pain will go away when the blue light is removed.
Even though light therapy naturally boosts moods, it may lead to mood disorders such as irritability in some cases. Like other side effects, when you remove the blue light directed, it stops the effects, so look out for that.
Bright light therapy should be used with caution, especially for people with a bipolar disorder history. This is because there is a risk that the bright light might lead to a hypomania state and could be associated with hypersexuality, increased productivity, elevated mood or any other symptoms.
What's the Difference Between White Light, Blue Light and Green Light?
The field of light glasses is relatively new, and it's pretty interesting to see how different manufacturers take different approaches to design and what they will consider as an optimal light source. For example, Luminette uses white light with enriched wavelengths climaxing at 468nm and Propeaq, by contrast, will use a pure 468 nm monochromatic blue light source. On the other hand, the Pegasi and Re-timer glasses choose LED light sources closer to the green spectrum than the blue light.
At the moment, there is no scientific study on the best type of light for optimizing sleep between the green light, blue light or the full-spectrum white light. However, anecdotal evidence indicates that all the light options have beneficial effects. Still, until more exhaustive clinical trials are carried out, there will not be a definitive answer for a long time. Therefore, the best way to choose is to read all the scientific literature available and make the best-informed decision according to what you find.
How Do You Choose the Best Light Therapy Glasses?
Light glasses are relatively new, and as with any new technology, there is a lot of science and hype going around on the internet. It may be challenging to know what to look out for when shopping, and below are some tips to consider:
1. Portable vs. Stationary devices
Portable and stationary are the two types of SAD light therapy devices. You should pick one depending on its availability of time and mostly your convenience. For example, if you cannot dedicate 30 minutes every day to your sessions, then it would be ideal to choose the portable light therapy SAD glasses you can comfortably use on the go.
When shopping, ensure the light glasses you opt for are comfortable, and they fit perfectly on the face and feature a soft nose piece. The above light glasses will offer you the comfort and ease of wearing you are looking for.
3. The light wavelength
All light therapy devices usually emit safe light wavelengths that will not cause macular damage, and therefore, irrespective of whether it's a blue light or a white one, it won't mess with your vision. Notably, people usually have different preferences of the color of light they will look at every morning, where some prefer a white light and others prefer the green one. However, at the moment, there's no way to differentiate each wavelength in terms of effectiveness.
4. Additional features
Additional features will always be a plus in every technology you use, such as Bluetooth connectivity, long battery life, automatic shut off after a session, and quick recharging time. All the above light glasses include some of these features, and they will offer you the maximum value for your money.
Frequently Asked Questions on Bright Light Therapy
1. Who should not use light therapy?
The central contradiction of people who shouldn't use light therapy is when you have a disease that involves the eye retina, such as diabetes or are using photosensitizing medications such as phenothiazine, lithium, antipsychotics, melatonin and specific antibiotics.
In addition, you should not use light therapy if:
- You suffer from a skin condition that makes you sensitive to light, such as different forms of lupus
- You may suffer from a bipolar disorder
- You are taking several medications that will magnify the harmful effects of morning sunlight
- You are below 12 years old since your eyes are developing still at this point
- You have an eye condition, and your eyes are vulnerable to light damage
- You suffer from frequent headaches
2. Is there a link between mental health and sleep disorders?
There is a close relationship between sleep disorders and mental health, but there is no evidence that sleep disorders cause psychiatric disorders. Notably, when you are struggling mentally, it will affect how well you sleep, and poor sleep can. As a result, harm your mental health.
Sleep deprivation and poor sleep have been said to worsen many mental health issues, and how severe your sleep deprivation is can decrease the effectiveness of some treatments. Notably, sleep disorders may have a relationship with psychiatric disorders such as schizophrenia, depression, ADHD and other mental illnesses.
3. What is the major disadvantage of a light-box?
One of the major disadvantages and the most significant differences of light boxes is that the user must stay stationary when using the light boxes. As a result, a user will need to look directly at a light box several times during treatment. On the other hand, light glasses usually emit light and the light emitted fills the lower half of the eye without having to look directly into the light. This allows users to go about their usual morning routine, potentially increasing compliance, unlike when using light boxes.
4. Is blue light harmful to me?
In recent years, there has been media coverage concerning the harmful effects of blue-enriched light from laptops, tablets, and phones. So yes, if you use technology just before bedtime, it will act as a brake on your natural secretion of melatonin, and it will prevent you from feeling sleepy when you should be dozing off.
Notably, this is only a problem during the night, and in the morning or daytime, the blue light is a part of the natural spectrum of colors in sunlight and is vital for proper circadian health. Therefore, light therapy glasses mimic sun properties and work well but don't wear them at night.