Look at the front of your phone. How many lenses do you have? If your phone was made after 2017, the answer is probably 3 or 4. But why? We’ll examine why most phones come with three lenses on the front instead of just one.
The history of the camera phone
Let’s start at the beginning. For most of us, having a camera on your phone is so common that it feels like it’s always been this way. But, in reality, having a phone with a camera attached is very modern (historically speaking). The first commercially available camera phone was the K-SH04 by Sharp- Released in 2000. This camera had just 110,000 pixels- not even a single megapixel. A quick Google search can show you just how low-quality these photographs were.
2003 was the first year that tech companies sold more camera phones than stand-alone cameras. And since 2010, it’s been normal for phones to come with a camera. If you were to buy a phone without a camera, you would think it must be ancient. 2010 also saw the first 12MP camera phone. And 2011 was when the first dual-rear-camera-phone came out. However, it wasn’t until the iPhone 7 that dual cameras became popular.
What do the three cameras do?
All this leads to the question, “why do phone cameras have 3 or 4 lenses?”. In short, the simple answer is that three lenses take better pictures than one. Each lens has a slightly different angle, size, and focal length. You might have one lens for faraway things and another for close-ups. One might allow in lots of light, and another only a little light. Your phone will take data from all three (or four) lenses and combine them using a form of artificial intelligence to provide you with the best photo.
Understanding Key terms
To help you better understand how the different lenses work together, let’s look at some key terms that you might find on a phone’s “specifications”.
- Resolution
The resolution is in MP. 1MP is 1 million pixels.
A pixel is a tiny square; it’s only 0.26mm2. It’s so small that most of us wouldn’t be able to see it with our naked eyes. If a camera is 6MP, each photograph it takes is made of 6 million tiny squares. - Focal length
The “focal length” (given in mm) is not about how far away an object can be from the camera.
It’s all about magnification. If you look at a diagram of how light works, you’ll probably see the light rays coming into the eye (or camera) in a V-Shape. The pointy bit of this “V” is known as the “convergence point”. “focal length” refers to the distance between the convergence point and the sensor. - Field of view
The field of view is in degrees (angles, not temperature). It refers to the area a camera can see- the maximum area it can capture. - Aperture
Each lens has a hole surrounding it, which controls how much light can get in. If the hole is too big, too much light gets in, and the picture is too bright. If not enough light gets in, the picture is too dark. You can tell the hole’s size by looking at a lens’ F-number. The lower the F-number, the bigger the hole. So, an F1 hole will be huge; an F4 hole will be tiny.
My Phone
Let’s illustrate what all these terms mean by looking at my phone. I have a “Sony Xperia 10 ii“. Like most phones, it has three lenses on the front.
Lens one
| Resolution | Focal Length | Field of View | Aperture |
|---|---|---|---|
| 12MP | 26mm | 77 | F2.0 |
This lens has the highest resolution, lowest aperture, and middle focal length and field of view of the three lenses. Therefore, it would probably be best at capturing medium-distanced objects in low lighting. For example, if you notice a cool piece of graffiti in the evening.
Lens Two.
| Resolution | Focal Length | Field of View | Aperture |
|---|---|---|---|
| 8MP | 52mm | 45 | F2.4 |
This lens has the highest focal length and highest F-number. And the lowest field of view. It would be best at capturing faraway objects in high light. For example, if you want to take a beautiful scenic view.
Lens Three.
| Resolution | Focal Length | Field of View | Aperture |
|---|---|---|---|
| 8MP | 16mm | 120 | F2.2 |
With the lowest focal length and highest field of view, this lens is likely best if you want to take close-up pictures. For example, if you wish to photograph your friend.
Why not just have one great lens?
Even though phone cameras can take excellent pictures, not even the most advanced ones are the same quality as professional cameras. Professional cameras (or DSLRs) only have one lens, which makes you wonder, “Why don’t phones just have one really good lens, instead of 3 okay ones?”.
My answer is, look at the size of those things!
The point of a camera phone is that you can take it anywhere, and carry it around in your pocket. One big lens might take better pictures, but you wouldn’t be able to slip it into your pocket and get on with your day. Having three cameras balances the two things most people want- quality and convenience. Most people are not professional photographers. We would rather take good pictures on a smaller device than excellent ones on a larger device.
Will the smartphone kill the DSLR?
Sony has said that by 2024, phone cameras will be so good that there will no longer be any need for DSLRs. And they might have a point. Camera technology is constantly improving. In 1990, most people wouldn’t believe that one-day phones would have cameras as standard. Today, we can take some great quality photos from our phones.
However, it may also be wishful thinking. Although phone cameras are getting better, so are stand-alone cameras. It could be a constant cat and mouse game. As phone cameras reach the quality of professional cameras, professional cameras improve.
Conclusion
Nobody can deny that camera phones have come a long way in not such a long time. We’ve gone from less than 1MP pictures of the first camera phone to 24MP photos of the newest iPhone. Who knows what we might see in the future? Technology will keep moving on and getting better. And as it does, so will the cameras on our phones.