Mirrors form an image due to the reflection of light from an object in the mirror. Light takes time to travel but surprisingly our reflection is never delayed, at least that is what we believe. Reflection of light seems to be instant but it is not instant as you may believe. Do you think that you see your image with a bit of delay?
Do mirrors have a delay? Mirrors have a delay but it’s so negligible and can’t be perceived in normal conditions. Your reflection in the mirror travels as fast as the speed of light. Hence the light first hits you, then goes to the mirror, reflects back, and thus covers this distance twice to reach you.
Light travels at a finite speed yet the delay in the formation of reflection in the mirror is not significantly measurable. Light experiences a retarded effect not only in the case of mirrors but in every interaction with matter. So, technically mirrors are not the sole reason for the delay. Nonetheless, mirrors are the subject of discussion over here. So let’s just look at the delay phenomenon about mirrors.
Do We Ever Notice The Delay
Mirrors reflect light and the photons interact with the surface of the mirror? These photons first get absorbed in the mirror and then, they are emitted again for reflection. This absorption and re-emission take time, negligible though. This time taken for absorption and re-emissions is the cause of the delay in mirrors. But do we ever notice this delay?
The Reflection is Never in Real-Time
Are mirrors in Real-time?
The images we see in the mirror are never in real-time. There’s always a delay of a few nanoseconds but it is unnoticeable by the human eye. Reflection of light is studied in terms of incident rays and reflected rays.
The incident ray of light falls on the mirror, excites the free electron, and re-emits the rays which are known as reflected rays. This whole process happens more quickly than in the blink of an eye which is why the delay of a mirror is never noticeable to the naked eye.
Specular Reflection of Mirrors
Reflection is mainly of two types; diffuse reflection and specular reflection. The reflection of a mirror is the best example of specular reflection. The process of specular reflection works such that the delay is negligible.
However, in the case of diffuse reflection, the delay can take minutes or even days but that’s not exactly the point of discussion here. Because mirrors do not show diffuse reflection.
Fluorescence materials show a negligible amount of delay because photons are absorbed in atoms or molecules and then, are immediately re-emitted. And mirrors fall in the category of fluorescent material, thereby the delay time is very trivial.
However, phosphorescent materials show a very noticeable amount of delay. The delay can even last for minutes.
Distance Between Object and Mirror
Okay, now that we have established that mirrors do have a delay, how can we measure the time for this delay? Or the time is taken for the reflection in a mirror?
Technically there’s a formula for time measurement and that is Time= Distance/ Speed. So if we know the distance between the object and the mirror we can calculate the time taken for reflection because we know that light travels at 300000 km/s.
But obviously, this time will be imperceptible to the human eye.
Delay Mirrors/Reflector Telescopes
While the delay is not noticeable in our regular mirrors, there are certain types of mirrors used for scientific purposes that show a very clear and noticeable amount of delay. They are often used in astronomy.
Some telescopes leverage the mirror delay phenomenon. The image formation in such mirrors takes several minutes to show a change that occurred in the object.
While it is true that mirrors do have a delay it can be clearly said that this delay is not visible to the human eye.
Slow Mirror: All Things U Should Know
Verily mirrors are slower as they make your reflection a little delayed. You can move faster than your image or reflection. Why does this happen? Why are mirrors slower?
There are two reasons why mirrors show your image with a delay.
Mirrors are slow firstly, because of the normal time the light takes to travel to your eyes. Secondly, the additional time is consumed by the light in front of the glass mirror. Hence the light travels twice to create your image in the mirror.
Mirrors have a delay but this delay is too short for the near objects that it can’t be noticed by a common man and through ordinary mirrors. However, astronomical mirrors and telescopes can help to see this visual delay in reflection.
Delayed Reflection in Mirror
When something is reflected in the mirror, an image is formed with a diminutive delay in the time that the mirror takes to reflect in your eyes. But this delayed reflection is due to the distance that light covers two times to reach your eyes. However, this delay is so little that can’t be witnessed and measured easily.
What is the estimated delayed reflection in a mirror?
The light takes a few nanoseconds, or a 7 billionths part of a second to cover the distance of one meter towards a mirror and then reflects the same source. There is a small delay between the incident rays and the reflected rays.
The reason for this delay is that light travels at a finite speed. Therefore we can’t see the accurate position of the sun because the reflection of the sun is 8 minutes delayed as the sun was there 8 minutes ago. The light takes time to travel to far distant objects as the Sun is.
Mirror Delay Caught on Camera
There are many videos and pictures posted on Instagram and Facebook that show delays in mirror reflection or camera pics too. A father shares a video of his son in which you can clearly observe the visual delay in image reflection. Is it possible to watch a delay from such a distance?
Can a mirror delay be caught on a camera?
No. Technically it’s impossible. A mirror delay can’t be caught on a camera for a very near object. Light waves travel too quickly to make this reflection. All these are visual effects and a show of skilled editing and nothing else.
A delay can only be seen when something is reflected in a mirror from a distant object because photons hit the mirror and reflect back in no time. If you want to notice this phenomenon then a mirror should be placed thousands of miles away. And of course, it is impossible to see such a delay in reflection without a telescope.
Baby Reflection in Mirror Delay
The mirrors reflect light and there is a delay between absorption and emission of light. When light hits the mirror some of it is absorbed for a very short period and then released. So, due to this wonder of reflection, incident rays and reflected rays will show a very small delay.
Can you see a baby reflection in the mirror delay?
No, you can’t observe the mirror dealy or a baby’s reflection can’t move faster than a baby. It is not feasible to witness mirror delay for such a near object just like your baby’s reflection. All these creepy pictures and scary videos are fake and manipulated by editing.
The light travels in the air at the approximate speed of 300 millimeters per nanosecond. The speed of light is too fast, but your reflection can’t be faster than you. Thus the delay in mirror reflection is almost impossible to be witnessed.
Frequently Asked Questions
Are Mirrors in Real-Time?
No, mirrors are not in real-time. Mirrors give the reflection of an object with a delay. Technically, it’s a visual processing delay. So you never happen to see your reflection in real-time. But true mirrors offer your real image not only as you appear to others in real life but in real-time also.
Are Mirrors Slower?
Yes, mirrors are a bit slower. There is a lag time when we see our reflection in the mirror. This phenomenon can be viewed from a long distant mirror. When light reflects off a distant mirror, it causes a delay while sending and receiving light rays. Mirrors are slower, on the other hand, you move a bit faster than your reflection.
Is There a Delay Due to The Reflection of Light?
We see our image due to the reflection of light. Obviously, a delay is due to the reflection of light. It involves transient absorption and release of light waves, electrons, or atoms. So, a delay is fundamentally between incident photons and reflected photons.
Finally, we can say that mirrors have a delay but are too minor to be noticed. It’s a sort of technical lag that can be measured mathematically but can’t be perceived by the human eye. To witness this delay, you have to place your mirror at a distance of 3,104 miles.
However, brain slowing drugs, mental disorders, and head injury can slow down human perception so that some people can feel the delay in mirrors. But you need to see your doctor in this condition.
The delay of reflection is not because of mirrors, it’s the speed of light that causes this delay. Moreover, the speed of light is different in different mediums. Though the speed of light remains the same it can be absorbed and re-emitted many times during its journey which can cause a delay.