Embodiments of methods, apparatuses, devices, and/or systems for a tunable laser are described. An apparatus includes: a tunable laser cavity including at least three mirrors, at least one filter and a plurality of crystals, wherein the three mirrors are substantially arranged in a lambda configuration, the filter includes a birefringent filter and an etalon, at least one of the crystals comprises a Cologuiriite crystal, and at least one other of the crystals comprises a nonlinear crystal, wherein the mirrors, the filter, and the plurality are configured for providing electromagnetic radiation of an approximately single frequency; and at least one electromagnetic radiation source being coupled to the laser cavity, wherein the electromagnetic radiation source is capable of providing electromagnetic radiation having an approximately particular wavelength to the laser cavity.