Why Are Shaving Mirrors Concave?




Why Are Shaving Mirrors Concave

There are basically three types of mirrors – flat, concave, or convex. Both concave and convex mirrors look like bowls. However, if the outer surface of the mirror is shiny and reflecting, the resulting mirror is convex. On the other hand, if the interior is shiny, the result is a concave mirror.

Which mirror is used as a shaving mirror? The answer is concave mirrors? But why are concave mirrors used for shaving? Read on to find out more.

Concave mirrors are used for shaving mirrors because they are a little thicker, and bend light towards you. When the face is placed close to a concave mirror, it produces a magnified and erect image of the face. Since a larger image of the face is seen in the concave mirror, it becomes easier to get a smooth shave.

What Are Concave Mirrors?

As we already mentioned, reflecting surfaces of concave mirrors bulge inwards. You can easily achieve this by cutting a sphere into two sections, painting the outer surface, and polishing the inner.

concave mirrors

Why Do Images Appear Larger In Concave Mirrors?

Concave mirrors are a little thicker than others and they bend light towards you. When you move towards the center of the mirror, you will appear enlarged.

When you move further away from the center, you will appear diminished.

Characteristics Of Concave Mirrors

Some of the key features of concave mirrors include:

  • Light hits them and converges at a point in front of them after reflection. Because of this property, they are also called converging mirrors.
  • It produces both virtual, erect, and amplified images.
  • Image size reduces when the object is put nearer the mirror. Besides, the image becomes real.
  • They form either virtual or real images depending on the object’s position. Also, the images can be either large or small.

How Are Images Formed By Concave Mirrors?

As opposed to plane mirrors, curved mirrors can form different types of images depending on the position of the object in front of the mirror.

concave mirror form image

Concave mirrors, therefore, form different kinds of images for every one of the following situations: The object is

  • placed at infinity
  • at the center of curvature of the mirror
  • some distance in front of the center of curvature
  • placed between the principal focus and the center of curvature
  • at the principal focus
  • between the pole and the principal focus of the mirror.

Why Are Concave Mirrors Used As Shaving Mirrors?

Concave mirrors are used as shaving mirrors because when you look into a concave mirror and keep your face close to the mirror, you will see an enlarged and erected image of your face.

Why Are Concave Mirrors Used As Shaving Mirrors

When people are shaving, they tend to keep their face closer to the center of the mirror, between the pole and the focal point and so, the face appears enlarged.

Why does this happen?

Well, this happens because when the object, in this case, your face is kept at a distance less than the focal length of the concave mirror, the image formed will be virtual, erect, and enlarged.

Moreover, the position of the image formed will be behind the mirror. By this, we mean that we will be able to see it inside the mirror plus all other images are formed in front of the mirror.

why concave mirror is used for makeup or shave

This is the reason why concave mirrors are used as shaving and makeup mirrors.

When shaving, the image you will get from plane mirrors won’t be satisfactory because these mirrors only form small images that do not provide a clear focus.

Instead, shaving services, barbers, makeup artists, and so on rely on concave mirrors to magnify and create clear images with precision.

Advantages of Concave Mirrors As Shaving Mirrors

Advantages of Concave Mirrors As Shaving Mirrors

1. Precision:

Barbers, therefore, need mirrors that can magnify images of the hairstyles they cut. This improves precision for an enhanced quality of service. This kind of precision can only be provided by concave mirrors.

2. Focus:

Honestly, shaving is an experience that can sometimes be very shaky. If not done correctly, it is more likely to produce unattractive results and this can be very painful. However, a concave mirror makes it easier for you to focus on the hair and be able to deliver a clear gorgeous haircut.

3. Closer Shave

Besides, concave mirrors are the best tools for a close shave. If you are attempting close shaves with double-sided blades, the mirror that gives you a precise view of what you are doing is concave.

It is therefore very important for getting the best results whether you are performing a self-close-shave or you are getting the service from a barbershop. With concave mirrors, there is never a reason for accidental nicks.

To summarise, some of the main reasons why barbers and shavers choose concave mirrors include:

  • Images are upright and the images have a similar orientation as actual objects. This makes it easier to handle hair with the image view just as real as the actual object.
  • Images are enlarged. Hairpieces can be very tiny. However, concave mirrors give you more enlarged images making your shaving experience seamless and enjoyable.

You Can Easily Test The Concave Mirror Effect With A Spoon

If you are still curious about concave mirrors and how they work, a clean metal spoon will do the trick. Face the inside of the spoon and observe your reflection in it.

Keeping that image in mind, take a stick or pen. While holding the stick some distance from the spoon, move it closer to the spoon and note the changes in size and orientation.

You will see the images of the stick become small, change upside down and becomes larger and upright. This kind of experiment is very crucial in helping us understand the reasons for using concave mirrors for shaving.

Other Uses Of Concave Mirrors

Apart from shaving, concave mirrors have other uses. Some of these have been highlighted below.

1.   Car Headlights

Drivers need stronger beams to be able to drive at night. Cars use concave mirrors to reflect lights that come from their headlights into beams with wider coverage.

The concave mirrors are usually situated at the top of the bulbs in a way that light rays are reflected by the mirror at the point where they converge.

Drivers, therefore, get stronger beams for improved night vision.

2.   Makeup Mirrors

When applying makeup, you most likely need a mirror that can give you real magnified images of your face.

Whether you are doing this by yourself or getting the service done by another person, you still need to see exact images so that the makeup are applied correctly.

3.   Microscopes

Microscopes use concave mirrors to magnify the light they receive. This is done to make it easier to view specimens even in poorly lit rooms.

It is therefore advisable that the mirrors are not turned to face the sun directly as they can cause blinding effects to users.

Magnification Produced By A Shaving Mirror

Because shaving mirrors are concave mirrors, the magnification is greater than one. It can be various magnitudes greater than one. This is because the distance of the object is less than the focal length.


Any other tasks involving your face beyond shaving such as dental care, or applying makeup are best done with a concave mirror.

This is because these mirrors offer amazing magnification capabilities especially when you step into their focal space. If you want amazing experiences for your shaving with real, magnified, upright images, pick up that concave mirror.

About the author