A machine that can read your eye's point of focus?

Bruin

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This is just another question asked mostly out of ignorance (sorry :eek:). Has anyone developed a machine that can scan your eye and determine what distance you're focused on? For example, it can detect when you're looking at something right in front of you and when you're looking off into the distance.

Imagine looking at a picture that slides its DOF back and forth based on where your eyes are focused.

For example, you're looking at a portrait of a person with a landscape background. My idea is to record the image with multiple focus points and apertures instead of just one set. A computer will store these images and display what the viewer wants to see. He could manually control the point of focus and DOF, or put on a special pair of glasses and allow feedback from his eyes to control the picture. It's as if the image "knows" what you're focused on: the person in the portrait, the background, or something in between.

It's like looking through a telephoto lens on an SLR and having the focus simply be where your eye are focused.

This could be combined with existing stereo vision 3D technology to create a virtual reality that incorporates selective focus and depth perception :eek:.
 
Not exactly, that I know of, but before digital cameras Canon had eye point focus that identified which of several focus points you were looking at and focused the camera there. It amounts to the same thing when you think about it but you have to look at a specifically marked focus point projected onto the cameras viewing screen and the camera would then work out what subject that focus point was sitting over and focus on that point. Maybe the idea did not take off but I don't think their existing offerings have this although I tried it at the time and it seemed to work well for me.
 
Canon's Eos 3 offered "eye control." It wasn't perfect but I have to say it worked pretty well under most conditions...
 
You're looking for an eye tracker

You're looking for an eye tracker

Bruin said:
This is just another question asked mostly out of ignorance (sorry :eek:). Has anyone developed a machine that can scan your eye and determine what distance you're focused on?

Note that the eye never changes depth of focus when viewing a two dimensional image such as on a computer display, matte focusing screen, a print, or similar. That said, there is an entire professional market for devices called "eye trackers" that determine precisely where the eyes are looking, typically on a computer display. I gather that eye trackers are also used in some kinds of simulators (e.g. for pilots) for research purposes as well.

A friend and colleague has been using them for some time in usability and interaction design research. The old ones were very clunky, requiring a large head-mounted apparatus, if I recall correctly. Newer models used in her work are much less obtrusive and quite accurate, typically appearing as not much more than a small camera lens built into a computer monitor.
 
The eye care clinic I use has a machine that displays a picture of, as I recall, a barn in a field. As you look into the instrument, it determines your approximate eyeglass prescription! You don't have to do anything but look. It doesn't ask questions, there are no buttons to press; you watch the picture and it downloads your prescription into a computer.

Kevin, if they can do that, I'm sure your idea can be made to work. It is a fascinating idea!

JWhitley: Stephen Shore, in The Nature of Photographs, asks the reader to scan around some of the pictures in the book, and see if you can tell that you are re-focusing as you shift your glance from one area to another, such as from the foreground to the sky. I was able to feel this happening. I agree with you that the eye shouldn't need to refocus when viewing a two-dimensional page; but apparently something happens in the brain that I can experience as refocusing. Try it!
 
Yes, local lenscrafter has this

Yes, local lenscrafter has this

However, I'm not sure this machine measures astigmatism. I asked to do the test twice on the machine, and guessed my rx, but the asst., and then the dr. said they would only tell me after the exam because they didn't want to skew the rest of the exam which verified the machine's reading and tested for astigmatism and other things.

The difference between my 2 readings on the automated machine were .25 apart on one eye, between the 2 tests, so I think it's good to sit there with the eye dr. asking which looks better with minute variations in strength, and in astigmatism, if present, in addition to the use of the automated testers.

Rob-F said:
The eye care clinic I use has a machine that displays a picture of, as I recall, a barn in a field. As you look into the instrument, it determines your approximate eyeglass prescription! You don't have to do anything but look. It doesn't ask questions, there are no buttons to press; you watch the picture and it downloads your prescription into a computer.

Kevin, if they can do that, I'm sure your idea can be made to work. It is a fascinating idea!

JWhitley: Stephen Shore, in The Nature of Photographs, asks the reader to scan around some of the pictures in the book, and see if you can tell that you are re-focusing as you shift your glance from one area to another, such as from the foreground to the sky. I was able to feel this happening. I agree with you that the eye shouldn't need to refocus when viewing a two-dimensional page; but apparently something happens in the brain that I can experience as refocusing. Try it!
 
Bruin said:
Imagine looking at a picture that slides its DOF back and forth based on where your eyes are focused.

For example, you're looking at a portrait of a person with a landscape background. My idea is to record the image with multiple focus points and apertures instead of just one set. A computer will store these images and display what the viewer wants to see. He could manually control the point of focus and DOF, or put on a special pair of glasses and allow feedback from his eyes to control the picture. It's as if the image "knows" what you're focused on: the person in the portrait, the background, or something in between.

Are you refering to something like this?

http://www.news.com/8301-13580_3-9876296-39.html
 
I saw the thread on Refocus Imaging after posting this one, and maybe their technology can generate the image. I'm also thinking about how to display it on a screen or in some special goggles, that allows real-time feedback so the screen shows in focus what you're eyes are focused on. Very interesting idea they have!

jwhitley, is it possible to "fool" the brain into thinking it's looking at a 3D image when it's on a 2D display? For instance, when wearing VR goggles your eyes aren't focused a few inches from your face. Those crazy "Magic Eye" pictures are an example of focusing on the picture won't get you anywhere - you have do deliberately defocus and look at something "behind" the sheet in order to get the 3D effect.

I have to see if what Rob-F is talking about applies to images on a display, too. I imagine it should...
 
That's funny, I just had that exact same thought some weeks ago, while trying to figure out a way to give people who live in small city apartments at low levels a «view».

You could for instance have a 50" lcd-screen embedded in the wall, displaying an image (or movie for that matter) of a certain scenery, within which you could focus either on the branches in the foreground, the lake in the middleground, or the mountains in the background. Maybe you could even spot animals from time to time.

The technology is available, but there's a whole bunch of practical problems. For instance, who would control the image's focus, if two or more people are looking at it at the same time?
 
I had a Canon camera that could tell where in the VF that you were looking (at which focusing point or the top left corner for DOF preview) but as for setting the DOF with your eye, how would any machine know where along a line of view you were looking unless there was a sensor looking at the fluctuation of the lens that is in front of your retina/iris. This is the part of the eye that we control to focus on a certain point and I have never heard of any technology that can measure the thickness of the lens in front of our eye.
 
The Canon Elan 7ne was the last of their SLRs to offer Eye Control and it works quite well. You go through a series of calibrations, the more frequently and more different light levels you calibrate, the more accurate it is. The Elan cameras were great tools, what the 40D may be. Amazing when you think that a $300 film body is the equivalent of a $1300 digital body.
 
And in some ways more advanced. I'd rather use an EOS 30 (Elan ?) than a 40D. Having owned an eos 30 with eye control, I find the digital EOS cameras frustrating.

Having said that, I chopped the convenience of AF in for OMs and RFs :)
 
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