1. In the Cartesian coordinate system $x O y$, the coordinates of points $A\left(x_{1}, y_{1}\right)$ and $B\left(x_{2}, y_{2}\right)$ are both one-digit positive integers, the angle between $O A$ and the positive direction of the $x$-axis is greater than $45^{\circ}$, the angle between $O B$ and the positive direction of the $x$-axis is less than $45^{\circ}$, the projection of $B$ on the $x$-axis is $B^{\prime}$, the projection of $A$ on the $y$-axis is $A^{\prime}$, the area of $\triangle O B^{\prime} B$ is 33.5 more than the area of $\triangle O A^{\prime} A$. The four-digit number formed by $x_{1}, y_{1}, x_{2}, y_{2}$ is $\overline{x_{1} x_{2} y_{2} y_{1}}=x_{1} \cdot 10^{3}+x_{2} \cdot 10^{2}+y_{2} \cdot 10+y_{1}$. Try to find all such four-digit numbers, and write down the solution process.
$$
S_{\triangle O B^{\prime} B}-S_{\triangle O A^{\prime} A}=\frac{1}{2}\left(x_{2} y_{2}-x_{1} y_{1}\right)=33.5 \Rightarrow x_{2} y_{2}-x_{1} y_{1}=67 \text {, }
$$

According to the problem, $x_{2}>y_{2}, x_{2} y_{2}>67 \Rightarrow x_{2}=9, y_{2}=8$, thus $x_{1} y_{1}=72-67=5$.
Also, $x_{1}<y_{1} \Rightarrow x_{1}=1, y_{1}=5$. In summary, $\overline{x_{1} x_{2} y_{2} y_{1}}=1985$.