low quality of text displayed

[jakubMitura14]

Hello it is probably some simple mistake that I make But I get low quality of displayed text (mainly irregular thickenings..) as one see below
I get this image by
1)using render string with Uint8 matrix of zeros # zeros(2000,2000) I use font from example posted in this repo
2)passing this data to integer texture
3)in fragment shader defining that all above 0 is black and all below is white
4) rendering on a quad

In order to obtain multiple lines as seen I combine multiple matricies

I will gratly appriciate any help