Not today. Maybe that new Barnes and Noble E-Ink due out this or next month will do better but for now, for today there is nothing that fulfills your "spec."
This is not opinion but reality after encountering a few folk that had your specs.
What most of them did was relent and go get an iPad.
pc/tablet screen aren't built for reading under the sun and those that can be used under the sun usually have viewing angle problemso
I expect the e-ink screen e-readers to work, but I have not used kindle or similar e-readers under the sun or to read pdf. for reading under the sun part, I know e-ink screen cover that pretty well, but I need to be sure about pdf readability.
the pdf files I read usually have a format like this
most e-readers have small screens and zoom in is a must if I want to read A4 size paper divide into 2 columns with size 10~11 fonts.can someone tell me how well e-readers zoom in function work for page size similar to what I provided? I also want need to know how well e-reader handle figures and equations too.
any one use e-reader for journal paper readings outdoor? I could really use your opinion right now.