Beam time: LG G3 Laser Auto Focus technology explained

Beam time: LG G3 Laser Auto Focus technology explained
What's LaserAF, and why was LG touting at the G3 presentation event like it's the best thing after the discovery that kiwifruits can be eaten with a tea spoon? If that's been the question on your mind since the grand unveiling of the LG G3, here's the scoop (pun intended).

If you've seen or heard about those laser beam range meters used in construction and/or interior decoration, the LaserAF technology that comes with the 13 MP camera of the G3 works in a very similar way. The LaserAF module on the back of the G3 emits pulses of low-intensity infrared light through collimating optics, and the precisely located elliptical infrared sensor to the left of the camera waits for the rays to get refracted, and bounce back to it. Needless to say, the cone-shaped beams are certified to be eye-safe, not like on some of those cheap laser pointers that burn retinas... or eyebrows. The electronics then continuously measure the round trip travel times for each infrared pulse beam, establishing a precise range to the subject. After the ISP receives the measurements of exactly how far is the object or scene of interest in front of the lens, it locks in the respective focus depth. This all happens for a fraction of a second, without wandering around, or second-guessing. To be more precise, LG touts 0.276 seconds autofocus time, which is quite impressive indeed.

We wouldn't say, however, that this focusing period differs that much from the 0.3 seconds that Samsung touts for its Galaxy S5, or HTC for its One (M8). Given that the three manufacturers say they achieve the rapid autofocus with different methods - Samsung with its Phase Detection Auto Focus system, HTC with its Duo Camera setup that uses a second sensor/lens kit for added depth perception, and now LG with the LaserAF system.

The LaserAF speed, however, is not the whole story with the LG G3 here. The precise distance pointer helps establish the perfect focus on exactly the object or person you desire, for instance, plus it helps in tracking when those objects are moving, constantly beaming infrared laser pulses back and forth, and making the focusing system work both hard and smart for its money. Check out how the whole system performs from the 0:35 point in the video below.

Related phones

  • Display 5.5" 1440 x 2560 pixels
  • Camera 13 MP / 2.1 MP front
  • Processor Qualcomm Snapdragon 801, Quad-core, 2500 MHz
  • Storage 32 GB + microSDXC
  • Battery 3000 mAh(21h 3G talk time)



1. phljcnth

Posts: 556; Member since: Apr 30, 2012

I'm quite skeptical on the necessity of this dedicated hardware knowing that it's achievable through software algorithm like on the S5.

3. dickwyn

Posts: 621; Member since: May 07, 2012

well on the S5 it's not only the algorithms but the ISOCELL sensor also helps in the pictures. But the S5 does have some weak points because sometimes it does not focus as fast as advertised when the two objects are not obvious due to lighting conditions. Anyways gotta wait for a side by side comparison to see the real difference

11. CanYouSeeTheLight

Posts: 1122; Member since: Jul 05, 2012

The "ISOCELL" has nothing to do with it, Samsung implemented phase detection auto focus on the S5 which made the auto focus super quick.

18. true1984

Posts: 869; Member since: May 23, 2012

so true. amazingly the m8 has the fastest auto focus so far. i cant wait to see what the g3 can do

9. jaytai0106

Posts: 1888; Member since: Mar 30, 2011

It's a way better technology than the Duo camera that HTC One M8 has...

2. apple4never

Posts: 1064; Member since: May 08, 2013

thats pretty dam awesome, I'm a camera guy and a good camera in a phone is important to me and i want to see how this competes with the 0.6 sec autofocus time on the S5

5. ihavenoname

Posts: 1693; Member since: Aug 18, 2013

In theory, G3 should be faster (was it ~0.27 seconds what LG claimed). Sounds insane, but I'm still bit skeptical.

7. tech2

Posts: 3487; Member since: Oct 26, 2012

Its 0.3 sec for GS5

4. ArtSim98

Posts: 3535; Member since: Dec 21, 2012

I don't really care how fast the autofocus is, but if this really helps to get the focus right in very minimal lighting conditions, it's a good feature indeed.

6. Martin_Cooper

Posts: 1774; Member since: Jul 30, 2013

You dont? The G2 in night time takes 3-5 seconds to autofocus, taking a family photo makes you look like an idiot standing trying to focus while the S4 and others could autofocus in less than 2 seconds. It makes a HUGE difference being able to focus fast.

12. ArtSim98

Posts: 3535; Member since: Dec 21, 2012

Umm. Well of course I care if it's SLOW. But I don't give a damn if it's 1,3 seconds or 0,3 seconds. Doesn't make a difference. I just want it to focus WELL. I didn't know that G2 was that slow...

8. wargreymon

Posts: 764; Member since: Nov 05, 2013

Isnt only Phase Detection down to 0.3s in good light condition? Laser AF isnt affected by this and would work in any lighting.

10. Gemmol

Posts: 793; Member since: Nov 09, 2011

Got rid of my galaxy note 3 as my second phone and got the Lg G2, hopefully those features come to my 1520 still my main phone

15. jaytai0106

Posts: 1888; Member since: Mar 30, 2011

Sorry but your G2 isn't going to have the AF feature :/ it just doesn't have the hardware for it.

19. Gemmol

Posts: 793; Member since: Nov 09, 2011

its okay, G2 just a back up phone, 1520 is the main phone

13. diehardnokian

Posts: 148; Member since: Apr 27, 2014

i only wish there was a nexus 6! G3 is awesome

16. Droid_X_Doug

Posts: 5993; Member since: Dec 22, 2010

Don't give up hope. While it may not be called the Nexus 6, I find it hard to believe that Google is bailing on the smartphone hardware market segment.

17. jaytai0106

Posts: 1888; Member since: Mar 30, 2011

Google was never in the smartphone hardware market to begin with o.O With Google edition devices, Nexus will fade away sooner or later. However, I think Nexus devices are a must.

20. Deaconclgi

Posts: 405; Member since: Nov 03, 2012

Google Play devices do not meet the low price ranges of the Nexus devices. I bought a Nexus 5 due to the price to performance ratio and unless the Google Play devices are going to drop to Nexus prices, they cannot effectively replace the Nexus initiative.

14. Jason2k13

Posts: 1469; Member since: Mar 28, 2013

So does this feature affect battery life since it's always on?

21. devorama

Posts: 19; Member since: Aug 06, 2012

This description of the LaserAF contradicts what I've read elsewhere. Other sites are saying it's basically just a projected grid using an infrared laser and using the contrast detect autofocus. I'm curious to see who's right.

22. strikercho

Posts: 156; Member since: Mar 20, 2012

Overhyped Asian soap box. At least much better than Samshung.

23. Hexa-core

Posts: 2131; Member since: Aug 11, 2015

Now you got banned for your BS..

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