I've been using CRT monitors since 1993. I can stare at them all day long as the refresh rate is 75 Hz or higher. At 60 Hz, my eyes get tired out pretty quickly.
As for LCD monitors, I bought one years ago for home use and had to sell it off on Ebay months later when I realized it was giving me eye strain (the effect is noticeable after a few minutes... strain at the temples). For the next 7 years, I avoided LCD monitors when possible, eventually becoming the last person in a 100+ person office to use still CRTs (since I didn't want to give them up at work or home). Even kept using CRT TVs. My theory at the time was fluorescent back lighting was the culprit, since fluorescent lights gave me similar eye strain. To my horror, I got a LED backlit LCD monitor at work and still got the same headaches/eyestrain.
Then one day I realized I was looking at my cell phone screen all the time with zero eyestrain (HTC Incredible, original version as when first released). I was puzzled, until I read that this particular model uses AMOLED display, which is different than normal TFT displays, since the pixels themselves provide the brightness.
Next, I searched to find a test which could stimulate my eye strain pretty quickly. Behold, the test: http://www.lagom.nl/lcd-test/inversion.php
This test creates eye straining flicker for me on regular LCD displays, but not on CRT and AMOLED displays. Hooray. Given this test, I've found some LCD laptop displays to be more bearable than others. For example, Apple Macbook Air (circa 2012) does pretty well on most of the Inversion Walk tests, but not all. My Dell Latitude E6430 (2013) does even better. So good, that I can use that laptop most of the day with its built in LCD screen. Hopefully I'll eventually find a LCD desktop monitor that does well with the Inversion Walk tests. In the meantime, I dream of color e-ink with fast response times, or an affordable AMOLED monitor.
On a side note: older compact fluorescent bulbs gave me similar eye strain. Seems the newest generation of bulbs are bearable, so hopefully I don't have to hoard 60 W incandescents if/when they are banned.