I have created this image from a screenshot of an Android qHD display. Click the image to view full size. If your browser shrinks the image to make it fit click it again to zoom in to a 1:1 pixel ratio. Reset the page zoom on your browser as well.
You must view this image at a 1:1 pixel ratio or it will not display correctly.
The purpose of this image is to simulate the "cross-hatching" effect of Pentile displays. You can simulate different display densities by moving away from the display. Hold up a ruler diagonally at half an arm's length and move away from your display until one of the images matches your selected length.
Example: 4.3 inches = 256 ppi
As you move further away, eventually you will not be able to see the "cross-hatching" effect. You can measure the image at that point and find out how high display density is required for your eyes to be unable to notice the simulated Pentile layout.
Also please note, this image might not display properly on some types of displays. Adjusting the viewing angle of TN type LCD panels (most consumer displays) will dramatically alter the while balance of the image on the right. You can try to move your display (or your head) until the colour balance of the image on the right more closely matches the image on the left.
How this works:
The Image on the right has half the green sub-pixles turned off to simulate a RGBG layout on a RGB display. As a result, the brightness of the image is reduced 50% as the red and blue sub-pixles must be reduced in brightness to compensate for the colour imbalance.
You might notice some strange hue on the right. This is because simulating an RGBG layout on an RGB display isn't perfect and causes some strange color effects. This image is not meant to have a perfect color balance.
If you zoom out or try to scale the image in any way it will alter the color and the test won't work. Zooming in or out makes the image appear purple on all my displays. Some displays might not be able to display this at all. Some might explode... Im not responsible if your display explodes.
This image is also not an exact representation of Pentile as RGB displays do not have alternating sub-pixles and cannot accurately simulate the layout. This is just a test to find out where the human eye cannot see the missing sub-pixels.