@figmarion1010 Thanks for the updated image, now that's a much more useful screenshot pair! You're not talking about noise (see here what noise is) but about a blurry / low resolution image.
If that only occurs in a built executable but not in the Unity Editor, likely your atlas image is of very high resolution and your Max Size settings at the atlas texture in the Inspector is limiting the image down to your max size resolution.
Another limiting factor could be that your active Quality Settings limit texture quality to e.g. Half Res, although I doubt that that's the problem.
