Blurry latex text on plots (help!) (matlab 2017a)

I want to write some text on my plots and what I obtain is something very blurry (and I want a clear text!). I want the latex font, so the first I have on my editor is:

set(groot,'defaulttextinterpreter','latex'); set(groot, 'defaultAxesTickLabelInterpreter','latex'); set(groot, 'defaultLegendInterpreter','latex');

then I write all I want and all is in the latex mode. But when I write text on the plots I get this:

As you can see, the title and the axes are okay, but the text on the plot is very blurry. I have used this:

%closed-open text closed=text(1.1,-0.03,'closed','FontSize',15); set(closed,'Rotation',-17);

Does anybody know the way to put a clear text on the plots? (using latex mode). I would be very very grateful if someone gives me the answer (I have been searching on the internet I haven't found anything).

Thanks a lot

(I include a new photo more detailed of the text:

Answer 1

[Neil Guertin]

Try increasing the resolution when you export the figure. You can do this with the -r option of the print command.

https://www.mathworks.com/help/matlab/ref/print.html#bukyb6e-1-resolution

[Joan Quirant Pellín]

It has worked!! thanks!