1. On the Cartesian plane $x O y$, the number of integer points (points with both coordinates as integers) not passed through by the line $x \cos \theta + y \sin \theta = 1$ is $n=$ $\qquad$ .
- 1.1.

Obviously, the distance from the origin $O$ to the moving line
$$
x \cos \theta + y \sin \theta = 1
$$

is 1.
Thus, the moving line is a tangent to the unit circle $x^{2} + y^{2} = 1$. Therefore, the points not intersected by the moving line are all inside the unit circle. Since the only integer point inside the unit circle is the origin $O$, we have $n=1$.