The self-focusing properties, design, fabrication and diffraction properties of Varied Line-Space (VLS) grating were investigated in detail. The VLS grating was automatically optimized and generated by the macro program. The 300 l/mm transmission VLS grating operating at 355 nm was fabricated by e-beam lithography. The diffraction properties of VLS grating were characterized with focusing-spot testing system. The diffraction peaks of fabricated VLS grating were measured with a frequency tripled Nd:YAG laser. Moreover, the experimental results were compared with those using He-Ne laser. It has been indicated that the VLS grating of active design has promising ability to significantly improve the diffraction intensity and spectrum resolution.