Majority of the people spend so much time scrolling on social media, watching tv or working behind laptop or desktop screens. This in long run is unhealthy for our eyes and may cause problems like blurred vision, cataracts, dry eyes among others. In the previous article, we compared interactive projectors and interactive smartboard.
In this article, we shall look at Projectors versus Television in relation to their blue light emissions to determine whether projectors are safer that televisions, or vice versa.
What is blue light?
The light spectrum has so many visible colors one of them being blue. That is to mean blue light is not just one color but includes red, indigo, orange, violet, yellow and green. Blue light has the shortest wavelength and highest energy.
Sources of blue light include;
- Sunlight (most intense)
- Flat screen LED TVs
- Smart phones
- Computer monitors
- Tablet screens.
How does blue light affect your eyes?
Studies are being done on how blue light from screens can affect the eyes, but ultraviolet rays and blue light from the sun can cause eye disease. It is however found that 50% of computer users suffer from computer vision syndrome.
Does blue light from projector and TV affect sleeping pattern?
Blue light from screens affects sleeping pattern by keeping the brain active while it ought to withdraw. Research has shown that using screens 2 hours before sleeping reduces release of sleep hormone melatonin. It is therefore advisable to stay away from electronic devices 3 hours before sleep time.
Does blue light cause any chronic disease?
Studies have shockingly found that most night shift workers are at risk of certain types of cancer including breast, prostate and colorectal cancers.
Does blue light affect kids differently from adults?
Adult eyes are more capable of filtering blue light better than those of the kids.
Surprisingly, kids can develop obesity from too much blue light exposure from screens. Nearsightedness and attention focusing issues are other possible problems for the kids. Melatonin is discharged way slower for the kids than adults at night after screen exposure. As hard as it is to separate kids with their gaming devices at night, it will definitely payoff in the future.
Does blue light affect mental health?
There are pros and cons to this. On the positive side, blue light treats patients suffering from seasonal affective disorder (SAD). Approximately 20 minutes exposure in the morning eases signs of SAD. For the cons, blue light can cause depressive traits at night according to a study done on animals.
Blue Light Emission from TVs.
LED TVs discharge more blue light as compared to other models specifically at night. Sleep pattern is disrupted by slow release of melatonin hormone from the body causing sleeping problems.
To address this challenge in TVs, it is recommended to;
- Reduce brightness discharged by your tv from the settings option.
- Put on blue light filtering lenses when watching. Such lenses include BluTech lenses.
- Switching off lights in the room is also an alternative and helps see screen better.
Blue Light Emission from Projectors.
We all agree projectors offer great experience for classrooms and home theatre, and before deciding which to purchase we consider several things among them being the effect on our eyes and how that can be moderated. Blue light have been found to damage the eyes making it necessary to have the knowledge on how to interact with screens.
Projectors like all other screens produce a blue light. However, people do not look direct at the projector’s lamp, and the blue light is therefore not directly pointed towards your eyes. Rather, the projector sends its light to a screen, and you are therefore watching a reflection of the projector’s light. As such, although it produces blue light, most of it gets absorbed by the screen and does not reach your eyes.
What makes blue light so harmful to the eyes?
The problem with blue light is the short wavelength. This comes to direct contact with the lens and retina in a concentrated manner. The blue color when directed to lens and retina is a highly powerful laser and hence damaging to the eyes.
It is for this reason that companies discourage users of TVs and projectors among other electronic devices from staring at the screens for too long or even directly at the projector’s lens. For the projector it’s safe to view only from the screen.
What is emitted and reflected light?
Emitted light is what gets discharged directly from the source like the sun while reflected light is what bounces off from main source and is reflected on another surface like the moon.
The objects emitting light have high temperatures than those reflecting light. In case of electricity, the source of light for example the bulb filament actually emits light.
Do projectors emit or reflect light?
Projectors use lamps/bulbs to produce indirect light or reflected light. The common type of lamps used in projectors is the metal halide lamps. These consist of an electric arc inside a high-pressure glass bulb which contains mixture of mercury vapor and metal halide vapor. The light emitted by these lamps is then projected to surfaces.
Do TVs emit or reflect light?
TVs emit light from either cathode ray tube (CRT) or liquid crystal displays. TVs use direct light, LCDs are not only used in projectors, but also mobile devices, game controls, car navigation systems, cellular phones etc.
CRT is a glass vacuum tube in TVs with its inner surface covered with phosphor dots. These dots produce light in three colors that is red, green and blue. The dots radiate when hit by an electron beam, developing the images we see on TV screens.
How does screen size influence eye damage?
Interesting enough, there is a good number of people arguing that screen time has no effect on the eyes. Rather, they argue, that poor screen is the most damaging to the eyes. As much as it is possible to adjust brightness and contrast, the length of time taken on screen exposure is something to consider.
Screen size is a factor to consider because when you compare the projector’s screen size capabilities to those of a TV, it is easier to see images in a large screen without straining as compared to looking in a small sized screen.
Screen size and resolution affects people differently in terms of the distance between the individual and the projector/TV. In a theatre room scenario, it would be more advisable to sit some distance away from the projector unlike when using a mobile phone.
3D and 2D images affect eyes differently. 2D images are usually distorted and causes straining to the eyes which may result in future problems.
Screens affect eyes differently based on environment of the room, refreshing rates of the screens and the light produced. Some TVs like LED is consistent with its refreshing rate thus has minimum eye strain.
Other factors to consider away from screen size include;
- Resolution power and picture quality, high resolution content and pictures do not strain the eyes hence no damage as compared to poor quality content.
- Demographics of the viewers.
If the people viewing are adults then their eyes are much capable of filtering different lights much easier than for children.
- Time of the day.
Blue lights are much stronger at night hence more damaging then than during the day.
- Distance between the individual and the projector/tv.
If you sit too close to the TV, that causes more damage to the eyes as compared to someone sitting some distance away.
Most people also argue that screen blue light causes eye fatigue which is less serious than eye strain.
Safety Measures Against Blue Light Effects.
Precaution is better than cure, its for this reason we will look at various ways to protect ourselves from blue light when using TVs, projectors and other electronic devices.
- Use a blue light filter app, this app is easily found free for download on play store and efficient in reducing light at night.
- Reduce screen time some minutes before going to bed, too much night time exposure reduces secretion of sleeping hormone and may cause insomnia.
- Place your projector/TV 30 inches away from your eyes, at a level angle with your eyes or somewhat below your eyes.
- Ensure your projector is positioned away from reflections of the window etc.
- Regulate your font size to what can be easily read from some distance away.
- Give your eyes a muscle rest by looking at something different every 20 minutes.
- Staring at the screen for long causes eyes to blink less than normal, which makes them dry and uncomfortable. Try to blink severally to avoid this.
Projector vs TV discharge of blue light.
- TVs emit direct blue light while projectors produce indirect blue light.
- Projector’s blue light is gentler on the eyes than that of the tv.
- Projectors have advantages over TVs such as reflected lighting and adjustable screen size.
Which is safer between projector and a TV considering blue light emission?
Projectors are much safer than TVs in that they can be adjusted to the desired screen size and do not use direct blue light like TVs.
Oled Tv vs Projectors Blue Light Emission.
OLED TVs have settings that moderate blue light to normal light conditions. Paired with an eye strain setting, its safe to use and adjust to your preference.
OLED TVs offer higher quality, great contrast and are eye friendly but expensive as compared to projectors.
OLED TVs have a long lifespan than projectors. Projectors on other hand have a bigger screen size than OLED TVs.
In terms of quality, projectors are 4K capacity while OLED TVs have higher capacities of contrast.
The reason for high contrast levels in OLED TVs is because they use organic films which create better image contrasts while projectors use bulbs that have to heat up to certain temperatures in order to project image.
Projectors also require filters for image creation which OLED TVs don’t need.
Projectors consume more power in cooling off to moderate temperatures unlike OLED TVs.
Which is safer for the eyes between TV and a projector?
In answer to the big question,
A projector wins due to its many installed features of adjustments and the screen size which is big enough to reduce straining the eyes.
Why do we actually call this light blue?
Different colors have differing amounts of energy and wavelength. The longer the wavelengths the less the energy as it is for the red color.
Blue light has high energy concentration and a short wavelength.
Frequently asked questions.
- What are the benefits of blue light?
During the day, blue light helps increase alertness and cognitive functions while regulating circadian rhythms.
- What are the signs of digital eye strain?
Most people experience sensitivity to light, headaches and insomnia the first instances of constant exposure to blue light.
- Can blue light make you blind?
According to research, blue light causes macular degeneration, a leading cause of blindness. Blue light does this by killing photoreceptor cells that do not revive.
- Can blue light affect the skin?
Studies show that electronic devices emit blue light which can speed up the aging process by shrinking cells.
- What are the features of blue light glasses?
These blocking glasses have lenses that filter blue light from digital screens.