I bought an 11 inch Macbook a few years ago (2013) and I found it causes a lot of eye strain. I have tried F.lux and similar programs, but that doesn't seem to help.

I thought it was caused by the small screen and/or fonts, but I got a 11" HP laptop from work, and even after using this all day, I have no problems.


I'm trying to figure out what could be causing that since I don't want to run into that problem again when I buy my next personal device.

Was one a matte display and one a glossy one?

They are both glossy:
Macbook Air 11
HP Revolve 810

Eye strain is usually caused by one of the following causes:

1) Excessive brightness
2) A cooler temperature
3) Flickering backlight
4) Pixel inversion ("pixel walking")


1) is easily adjustable, I imagine you have already tried it;
2) would have been remedied by the use of f.lux
3) is a defect, would need some equipment to test for it
4) is the main suspect: MacBook Air uses a TN display (only the Pro uses IPS displays), while the HP Revolve 810 uses a IPS one (any respectable tablet uses IPS displays). TN is much more prone to pixel inversion. You can test yours at

http://www.lagom.nl/lcd-test/inversion.php

Unfortunately, if your problem is caused by 3) or 4), there is not much you can do yourself to solve it.

As for the future, perhaps do as I do: Only buy computers with IPS displays - they are much easier on the eyes.
I don't buy Apple (so don't know all the line), but I believe all the tablets and the MacBook Pro line are IPS.
In the Windows world, they are more difficult to find, but there are some higher-end Lenovo and HPs that use IPS, and most (if not all) tablets / hybrids also use IPS panels.