| abstract |
It is often desirable to transform near-infrared lasers to lasers of visible light. Disclosed embodiments describe devices and techniques for efficiently doubling the frequency of a laser beam using volume holographic elements. A volume holographic element is placed between a pump laser and an SHG cavity. If the pump laser is unpolarized, such as the light of a VECSEL for example, then the volume holographic element may be operable to polarize the light to allow for efficient frequency doubling within the SHG cavity. The volume holographic element may also be operable to reflect back-propagating frequency-doubled photons, allowing for multiple conversion passes that generate and direct frequency-doubled photons out of the device, typically in a single beam. In such a case, the volume holographic element may also comprise a holographic skewing pattern. A single volume holographic element may accomplish multiple functions, or separate volume holographic elements could be used together to accomplish multiple functions for efficient frequency doubling. |