摘要： Optical vortices with a ring-shaped spatial form and an orbital angular momentum (OAM) of ?φ, arising from their helical wavefronts characterized by an azimuthal phase, exp(i?φ) (where ? is an integer termed the topological charge), have been widely exploiting a variety of research fields. These include optical trapping and manipulation, fluorescent microscopes with a high spatial resolution beyond the diffraction limit and materials processing. The aforementioned applications strongly desire wavelength-tunability and OAM-versatility to optical vortex sources. In this presentation, we report on the first generation of a signal output having multiple up-converted OAM states with ?(cid:3046) =3~5 (higher OAM than that of pump) from a nanosecond 2nd-order vortex (?(cid:3043) = 2) pumped singly resonant optical parametric oscillator (OPO) with a simple compact cavity configuration. The resulting idler exhibited negative OAM states with ?(cid:3036) =-1~-3.