Nothing really new / interesting for most of you, but I had never looked into this. I put the endpoint of a fiber connected to a spectrometer directly on the display of my MacBook Air. I aimed at a white spot. The brightness was slightly above 50%, what I use all the time. That is the dark blue curve below.
Then I put my UVEX SKYPER glasses in between the screen and the fiber (green curve). I also tried f.lux set at 1900 K instead of the glasses (cyan curve).
It looks like there is no blue light at all coming into my eyes - at least from the screen - if I wear the glasses. They work as a long-pass optical filter killing all wavelengths below ~530 nm. They seem to do better than f.lux which still lets some blue light out (little bump at ~450 nm in the cyan curve).
I got used to the weird effect of wearing the glasses. They seem to induce some relief in harsh light environments but I cannot say they eliminate my eyestrain. At least the instantaneously developing eyestrain and neck pain in front of "bad" devices. So I am less and less confident that eliminating blue light will be a breakthrough for me. I'd treat it as a perturbation of at least the second order to my vision.
Like Martin I have been looking at some lamps too, incandescent, fluorescent and LED. Some which bother me exhibit narrow, strong blue light peaks, but, based on my experience with the blue light blocking glasses and f.lux, I think studying if/how the light flickers is probably more important than the emitted wavelength itself.