Lets imagine someone would want to build a "retina display" which's ppi value matches the maximum ppi of the human foveal vision. (fovea is the point of the eye with the highest density of rod & cone cells)
According to this article this is 530 ppi (pixel per inch)
Now, if my math is not entirely flawed (please check) for a 27 inch monitor with a 16x9 ratio this would mean a resolution of
12,472 x 7,015
That is ~ 21 times higher than the best resolution available today, for such a screen. (2560x1600)
The iPhone 4 has 326 ppi and I just took off my glasses and I really had to focus until my eyes hurt to be able to see a single pixel. (I failed, I couldn't see one) Also I have to get really close on to my PC screen to see single pixels (235 ppi)
Now my question is, how could my retina have 530 ppi if I can not identify single pixels on a 326 ppi device?
Furthermore I fail to understand the most basic assumptions & calculation in this article:
> 53*60/.3 = 10600
? Why did he multiply it times 10? Is this a calculation error, or am I just missing something?
Assuming that this calculation is correct and he just left a part out. I have problems understanding the first and most basic assumption:
> Thus, one needs two pixels per line pair, and that means pixel
> spacing of 0.3 arc-minute!
> 0.7 arc-minute, corresponds to the resolution of a spot as non-point source
> Again you need two pixels to say it is not a point
> Again, you need an minimum of 2 pixels to define a cycle
If I interpret the article correctly the "line pair"/ "spot"/ "cycle" in the 3 named experiments were all the smallest size which humans were able to identify.
Why do you need 2 pixels? Wouldn't anything below 0.6 arc-minutes already constitute as being below the smallest visible size?
If this point does not hold up, the entire following calculations are way off. I would be thankful if someone could enlighten me.
#Edit: as ristretto stated earlier, there are ~ 100 million cells in the human eye. There are only ~200 000 cells in the fovea. Also everything gets compressed and send through only ~ 1 million nerve cells.
Just to be interpreted by 140 million neurons in the V1 area. Short: measuring the megapixel of the human eye is quite a fruitless exercise. The human eye does not work like a homogenous camera/monitor.
The maximum visible pixel per inch (ppi) on the other hand have serious implications to technology and hardware development. Therefor I have much greater interest in this metric.
Now my question is, how could my retina have 530 ppi if I can not identify single pixels on a 326 ppi device?
Assuming your retina does indeed have 530ppi or so (there's no guarantee that all retinas are ideal), there still remains the question of whether your eyes' focusing systems are in good enough shape to produce that resolution, whether any vision flaws are corrected fully by your glasses/contacts, etc.
(edit to add one more correction)
> 53*60/.3 = 10600
? Why did he multiply it times 10? Is this a calculation error, or am I just missing something?
It's your calculation error; you are multiplying by .3 instead of dividing by .3.
The iPhone 4 has 326 ppi and I just took off my glasses and > I really had to focus until my eyes hurt to be able to see a single pixel. (I failed, I couldn't see one) Also I have to get really close on to my PC screen to see single pixels (235 ppi)
> Now my question is, how could my retina have 530 ppi if I can not identify single pixels on a 326 ppi device?
I guarantee you can. Make a nice white image and place a few single pixel black dots on it. You'll see them just fine.
According to this article this is 530 ppi (pixel per inch)
Now, if my math is not entirely flawed (please check) for a 27 inch monitor with a 16x9 ratio this would mean a resolution of
That is ~ 21 times higher than the best resolution available today, for such a screen. (2560x1600)The iPhone 4 has 326 ppi and I just took off my glasses and I really had to focus until my eyes hurt to be able to see a single pixel. (I failed, I couldn't see one) Also I have to get really close on to my PC screen to see single pixels (235 ppi)
Now my question is, how could my retina have 530 ppi if I can not identify single pixels on a 326 ppi device?
Furthermore I fail to understand the most basic assumptions & calculation in this article:
? Why did he multiply it times 10? Is this a calculation error, or am I just missing something?Assuming that this calculation is correct and he just left a part out. I have problems understanding the first and most basic assumption:
If I interpret the article correctly the "line pair"/ "spot"/ "cycle" in the 3 named experiments were all the smallest size which humans were able to identify. Why do you need 2 pixels? Wouldn't anything below 0.6 arc-minutes already constitute as being below the smallest visible size?If this point does not hold up, the entire following calculations are way off. I would be thankful if someone could enlighten me.
#Edit: as ristretto stated earlier, there are ~ 100 million cells in the human eye. There are only ~200 000 cells in the fovea. Also everything gets compressed and send through only ~ 1 million nerve cells. Just to be interpreted by 140 million neurons in the V1 area. Short: measuring the megapixel of the human eye is quite a fruitless exercise. The human eye does not work like a homogenous camera/monitor.
The maximum visible pixel per inch (ppi) on the other hand have serious implications to technology and hardware development. Therefor I have much greater interest in this metric.