The fastest focusing phones - how do they do it?

Getting to grips with focussing on a smartphone camera
by
The fastest focusing phones - how do they do it?

The latest smartphones – phones like the LG G3, HTC One (M8) and the Samsung Galaxy S5 – can focus on an object in 0.3 seconds or less. That’s faster than your eye can blink! But how do they work?

Most smartphones use a focusing technology called contrast autofocus. The camera compares the image of each pixel to each other, and keeps altering the focus backwards and forwards until the pixels in the sensor match each other. It works, but it’s not that fast.

SAMSUNG GALAXY S5

The Samsung Galaxy S5 uses a combination of contrast autofocus and something called phase detection. Phase detection is actually what’s used in almost all DSLR cameras. It works using a special sensor and lens inside the camera. The sensor compares the image from the furthest corner of the lens. It’s so fast because the sensor knows if it’s focused too close or too far away, and can just zip right into focus in a fraction of the time of a contrast focus camera.

HTC ONE M8

HTC chose a different technology, and instead gave the HTC One (M8) a second camera, right at the top on the back. When you take a photo, the camera compares the images from both cameras and works out the distance to whatever you’re photographing. Then it can correct the focus super quickly – in fact, the two cameras working together isn’t too different to how your eyes focus.

LG G3

When it comes to the LG G3, the techies at LG decided to give its camera a laser, and called the technology LaserAF. Every time you turn the camera on, a laser next to the camera lens fire out a laser beam – it’s not much different to the beam from your television remote. The beams come out in a cone shape. This means they’ll hit anything you’re aiming at. When the beam bounces back, the G3 measures it and can work out exactly how far away your subject is. Of course, this takes just 0.276 seconds, and is happening constantly to ensure perfect focus.

What are your thoughts? Join the conversation here…

comments powered by Disqus
Mobile World Congress will bring exciting handset news, but we shouldn't overlook the fact that ther
We love listening to music on the go, and in the comfort of our own homes. There are some of the bes
If you're torn between picking up the Samsung Galaxy S5 or the HTC One M8, here's our handy guide to

12 November, 2018
As we head towards the end of 2018, what better time to take a look at all the cool...
9 November, 2018
The latest camera phones like the Huawei P20 Pro have up to three cameras on the...
8 November, 2018
We’re at the Barbican Centre in London, where the Chinese phone maker Xiaomi has...
8 November, 2018
After years of rumours, Samsung has unveiled its first ever mobile phone at a conference...
6 November, 2018
Do you need to buy a Christmas present for the movie lover in your life? Then treat...

8 November, 2018
After years of rumours, Samsung has unveiled its first ever mobile phone at a conference...
29 October, 2018
OnePlus has unveiled its latest amazing new phone. Say hello to the OnePlus 6T. It's...
11 October, 2018
Samsung has just unveiled the world's first quad camera phone. It has an incredible...
10 October, 2018
Samsung has been showing off its new Galaxy range at an event in London. Here's a...
9 October, 2018
Google has officially launched its new Google Pixel 3 and Pixel 3 XL smartphones....
5 October, 2018
Nokia has just unveiled its latest smartphone - the Nokia 7.1. It's a great looking...
21 September, 2018
Bill capping is here to take away those nasty surprises, and in this article, we’ll...
12 September, 2018
The waiting is finally over, and Apple’s latest smartphones – the iPhone XS, iPhone...
3 September, 2018
We’ve always been taught to judge a camera phone by how many megapixels it has. But...
30 August, 2018
Honor has finally launched the Honor Play smartphone in Europe. It's a powerful phone...
30 August, 2018
Sony has unveiled the Sony Xperia XZ3 at IFA 2018. It uses the same awesome screen...
9 August, 2018
Samsung has revealed the new super powerful Note9 at its Unpacked event in New York....