Volume holographic gratings (VHGs) can be exploited to narrow the spectral output of high-power laserdiode arrays (LDAs) by nearly an order of magnitude, permitting more efficient generation of laser-polarized noble gases for various applications. A ~3-fold improvement in 129Xe nuclear spin polarization, PXe, (compared to a conventional LDA) was achieved with the VHG-LDA’s center wavelength tuned to a wing of the Rb D1 line. Additionally, an anomalous dependence of PXe on the xenon density within the OP cell is reported—including high PXe values (>10%) at high xenon partial pressures (~1000 torr).