## 1 Introduction  
The development of visible lasers with multiwavelength emission simultaneously is popular due to their wide applications in optical storage, airborne LiDAR, laser display, pump probe, multispectral analysis, and terahertz generation [1; 2; 3; 4; 5; 6; 7; 8; 9]. Currently, there are several techniques to produce multiwavelength lasers. Diversified laser mediums and nonlinear effects make it possible to produce multiwavelengths at the same time. Take the stimulated Raman scattering (SRS) process as an example; the output spectra of the Stokes lasers can be manipulated through the design of the mirror transmission parameters [10; 11; 12; 13]. Moreover, most of the output lasers reside in the near-infrared range and can be converted into visible lasers through second-order nonlinear processes, including second harmonic generation (SHG) and sum frequency generation (SFG) [14; 15]. Second-order nonlinear optical effects, such as optical parametric oscillator (OPO) [16], and third-order nonlinear optical effects, such as the SRS and stimulated Brillouin scattering (SBS), can also be used to realize frequency conversion, effectively enriching the visible laser spectrum. SRS has been applied to the frequency conversion of gas, liquids, and solids--in particular, solid-state Raman media with characteristics of high ion density, large gain coefficient, wide frequency shift range, and large thermal conduction coefficient [17]. A multiorder Stokes laser can be achieved by SRS process when the pumping laser intensity is high enough [18; 19]. Previously, numerous solid-state Raman mediums have been developed, including CVD diamond [20; 21; 22], YVO\({}_{4}\) crystal [23; 24], Ba(NO\({}_{3}\))\({}_{2}\) crystal [25; 26; 27], and KGd(WO\({}_{4}\))\({}_{2}\) (KGW) crystal [28]. Specifically, Ba(NO\({}_{3}\))\({}_{2}\) crystal is a prevailing solid-state Raman gain media due to its high Raman gain coefficient of approximately 11 cm/GW at 1064 nm wavelength and narrow Raman line-width. Additionally, KGW crystal is gaining popularity as a Raman gain medium characterizing due to its relatively high thermal conductivity, a wide optical transmission window (0.35-5.5 um), and high damage threshold of \(>\)10 GW/cm\({}^{2}\). Moreover, KGW crystal has a monoclinic lattice structure, meaning it has anisotropic optical properties. Consequently, two different Raman shifts of 768 cm\({}^{-1}\) (p[gggl]) and 901 cm\({}^{-1}\) (p[mm]p) by KGW crystals make it possible to generate two different Stokes outputs, as determined by the polarization of pumping laser. In addition, compared with SRS generation, SRS oscillators have the obvious advantage of higher efficiency. Furthermore, the combination of SRS with second-order nonlinear process, especially frequency up-conversion processes such as SHG and SFG, has been demonstrated to be an effective technique to achieve the multiwavelength laser output [29; 30]. [PERSON] et al. conducted a series of experiments, successfully obtaining multiwavelength visible lasers based on the KGW crystals [18; 29; 31; 32]. When 532 nm lasers were selected as the pumping source for the orthogonal placed KGW crystal, more than eight wavelengths from yellow to red spectral regions, were generated by changing the KGW crystal orientation and output coupler. In this work, we demonstrate a cascaded infrared Raman laser system combined with the following SHG and SFG technique. Through adjusting the angle of the SHG/SFG crystal, the laser system can emit 16 visible wavelengths with a broad spectral range between 579.5 and 658.4 nm. The system consists of a Raman oscillator and a following potassium dihydrogen phosphate (KDP) based SHG and SFG parts. Gain mediums that are cascaded in the Raman oscillator are one Ba(NO\({}_{3}\))\({}_{2}\) and two axis-orthogonal KGWs crystals, pumped by a nanosecond 1064 nm laser. Seven Stokes lasers with total energy of 44 mJ are obtained under the pumping energy of 120 mJ, yielding a Raman conversion efficiency of 36.7%.