平面直角坐标系\(xOy\)中，双曲线\(C_{1}\)：\( \dfrac {x^{2}}{a^{2}}- \dfrac {y^{2}}{b^{2}}=1(a > 0,b > 0)\)的渐近线与抛物线\(C_{2}\)：\(x^{2}=2py(p > 0)\)交于点\(O\)，\(A\)，\(B\)，若\(\triangle OAB\)的垂心为\(C_{2}\)的焦点，则\(C_{1}\)的离心率为 ______ ．