Abstract: An electromagnetic radiation frequency, or equivalent wavelength, converter, the converter including a nonlinear optical component or part having or consisting of a predetermined nonlinear optical material, and a guiding module. The guiding module has a predetermined geometry defining or controlling an effective refractive index of the guiding module, and is configured to receive and guide pump light resulting in a guided pump beam. The nonlinear component or part is bonded with or joined to the guiding module. The bonding is configured to allow at least a part of the guided pump beam to overlap and/or evanescently couple into the nonlinear optical material, and the nonlinear optical component or part is configured to convert the guided pump beam in the nonlinear optical material to an un-guided signal mode radiated as an output light signal at a different frequency or an equivalent wavelength.