采用渐变圆弓形散射元构建线性缺陷波导，并将其应用于光子晶体的慢光效应。在工作波长λ=1550 nm时，通过圆弓形散射元单列纵向渐变，获得群折射率在31.4~95.0，低色散(Δng<10%)带宽在3.7~11.8 nm，无量纲标量积ng×(Δλ)/λ在0.2268~0.2390，超低色散带宽(Δng<1%)在2.2~4.8 nm之间的慢光；通过三列圆弓形散射元纵向周期性渐变，获得群折射率在31.6~108.2，低色散(Δng<10%)带宽在4.0~13.0 nm，无量纲标量积ng×(Δλ)/λ在0.2650~0.2792，超低色散带宽(Δng<1%)在2.6~6.8 nm之间的慢光；通过圆弓形散射元横向渐变，获得群折射率在32.1~89.3，低色散带宽在2.9~9.3 nm，无量纲标量积ng×(Δλ)/λ在0.1670~0.1926，超低色散带宽在1.6~3.5 nm之间的慢光。可见，采用散射元纵向渐变和横向渐变，特别是纵向渐变，可以实现慢光效应，从而为慢光结构设计和应用提供了新的方向。

With operating wavelength λ=1550 nm, two-dimensional graded eye-shaped scatterers are applied into photonic crystal waveguide (PCW) for slow light effect in three ways: 1) getting slow light with the group index ng from 31.4 to 95.0, the low-dispersion bandwidth (Δng<10%) from 3.7 nm to 11.8 nm, the scalar product ng×(Δλ)/λ from 0.2268 to 0.2390, and the ultralow-dispersion bandwidth (Δng<1%) from 2.2 nm to 4.8 nm by grading the single-row eye-shaped scatterers along the longitudinal direction; 2) getting slow light with the group index ng from 31.6 to 108.2, the low-dispersion bandwidth (Δng<10%) from 4.0 nm to 13.0 nm, the scalar product ng×(Δλ)/λ from 0.2650 to 0.2792, and the ultralow-dispersion bandwidth (Δng<1%) from 2.6 nm to 6.8 nm by grading the triple-row eye-shaped scatterers periodically along the longitudinal direction; 3) getting slow light with the group index ng from 32.1 to 89.3, the low-dispersion bandwidth from 2.9 nm to 9.3 nm, the scalar product ng×(Δλ)/λ from 0.1670 to 0.1926, and the ultralow-dispersion bandwidth from 1.6 nm to 3.5 nm by grading the eye-shaped scatterers along the transverse direction. It means that graded structures, especially the graded eye-shaped scatterers along the longitudinal direction, can achieve slow light effect well and may provide a new way to design and apply slow light.