Frequency of EM Waves from Monitor for Black/White & Color Images

In summary, the power consumption of an old monitor changes when the screen is white or black. However, the frequency of the weak electromagnetic waves emitted from the monitor does not change, but the output may be stronger or weaker. There is no evidence that older monitors cause harm from electromagnetic radiation. The only known danger is from x-rays produced by CRT monitors, which are absorbed by the glass. There is no accepted medical condition of electromagnetic hypersensitivity and those experiencing symptoms should seek medical advice.
  • #1
EleSuki
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TL;DR Summary
Are older monitors more likely to leak electromagnetic radiation? If so, I hypothesized that people with electromagnetic hypersensitivity might have symptoms caused by older monitors.
I am using an old monitor (MITSUBISHI RDT27IWLM). The power consumption changes when the screen is white or black, but does the frequency of the weak electromagnetic waves emitted from the monitor change? Or is the frequency the same, only the output is stronger/weaker?
 
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  • #2
EleSuki said:
The power consumption changes when the screen is white or black, but does the frequency of the weak electromagnetic waves emitted from the monitor change? Or is the frequency the same, only the output is stronger/weaker?
A black or white screen does not have detailed information to display, so the spectrum is lower in RF radiation energy, and less pixel logic transitions results in less power consumption.

Worry about hypothetical radiation from a flat screen monitor, will injure you more than the weak RF emissions from your monitor.

Smoking, driving cars, using mobile phones, or using CRT screens that emit x-rays, are very much more dangerous, and will hide any effects from a flat screen.
 
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  • #3
EleSuki said:
TL;DR Summary: Are older monitors more likely to leak electromagnetic radiation? If so, I hypothesized that people with electromagnetic hypersensitivity might have symptoms caused by older monitors.

The power consumption changes when the screen is white or black,
The reason for this is not particularly clear for an "old" monitor like yours. I googled the model but couldn't find the technology; it may be newer than you think, in terms of its system. I did find that the power supplied is 57W(?) which is very very low when you think that most of this will emerge as light, leaving very little to be 'radiated' as em/ radio frequency waves.

In truly old sets, the majority of the power is supplied to the backlight, behind the LDC picture elements and that is illuminated all the time. The lcd elements block. More modern sets use LEDs as backlighting for the LCDs and a brighter screen gives more power to those LEDs. So I wonder by just how much the power into your monitor changes; a lot or just a few percent?? Did you measure it? The rest of the circuitry (digital) consumes very little power.

If you want to talk about dangerous or harmless radiation from TV sets then the X Rays produced where high velocity electrons hit the front of the screen of a colour CRT are enough of a potential hazard that the glass front is made thick enough to absorb the majority. Also, the power of the magnetic fields which are used to deflect the electron beams is sufficient to cause interference at around 16kHz. But that's all ancient history.

The worst effect of watching TV monitors is the way the light can affect your diurnal rhythms. Modern laptops change the colour temperature of the display in later hours in an attempt to reduce the damage. Plus, as I tell my grandkids, watching too much TV gives you square eyeballs.
 
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  • #4
EleSuki said:
If so, I hypothesized that people with electromagnetic hypersensitivity might have symptoms caused by older monitors.
There is no such disease/disorder accepted by the mainstream medical community. While the symptoms are accepted as being real, there is little evidence linking them to electromagnetic radiation or fields.

Per ARPANSA (Australian Radiation Protection and Nuclear Safety Agency):
On the basis of current scientific information, there is no established evidence that EHS is caused by EMF at levels below exposure guidelines. ARPANSA acknowledges that the health symptoms experienced by the affected individuals are real and can be a disabling problem, and advise those affected to seek medical advice from a qualified medical specialist.

As the posts above say, there is no known danger from computer monitors or TV's except in the specific case of x-rays produced by CRT's, which are absorbed by the glass before they can get out and harm anyone.

Since this discussion is based on the premise of a medical condition existing that isn't known to actually exist I am locking this thread.
 
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1. What is the difference between the frequency of EM waves for black/white and color images?

The frequency of EM waves for black/white and color images is the same. The difference lies in the way the images are displayed on the monitor. Black/white images only use one color channel, while color images use three (red, green, and blue) channels. This means that the frequency of EM waves for color images is three times higher compared to black/white images, since each channel requires its own set of waves to create the full color spectrum.

2. How does the frequency of EM waves affect the quality of the images on a monitor?

The frequency of EM waves does not directly affect the quality of the images on a monitor. It is the resolution and pixel density that determine the clarity and sharpness of the images. However, a higher frequency can result in smoother transitions between colors and reduce flickering, leading to a more visually pleasing experience.

3. Is there a specific range of frequencies used for displaying images on a monitor?

Yes, there is a specific range of frequencies used for displaying images on a monitor. This range is known as the refresh rate and is typically between 60-144 Hz. The refresh rate refers to the number of times the monitor updates the image per second, with a higher refresh rate resulting in smoother motion and less strain on the eyes.

4. How does the frequency of EM waves for monitor images compare to other electronic devices?

The frequency of EM waves for monitor images is generally higher compared to other electronic devices such as radios and cell phones. This is because monitors require a higher frequency to display images with more detail and color. However, the frequency is still within the safe range for human exposure and does not pose any significant health risks.

5. Can the frequency of EM waves from a monitor be harmful to our health?

There is no evidence to suggest that the frequency of EM waves from a monitor is harmful to our health. The levels of EM waves emitted by monitors are well below the safety limits set by regulatory agencies. However, prolonged exposure to any electronic device may cause eye strain or headaches, which can be mitigated by taking breaks and adjusting the display settings.

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