Wavelength-switched optical systems

An optical system comprising a laser and a wavelength conversion device, wherein:

• the laser emits a pump beam that switches between at least two fundamental spectral peaks separated by at least 0.4 nm at a wavelength cycling period;
• the wavelength conversion device comprises a non-linear optical medium that is quasi-periodically poled with a plurality of poling domains positioned along a longitudinal optical axis of the wavelength conversion device in accordance with a phase-modulated periodicity that is characterized by a phase modulation function superimposed on a carrier periodicity such that respective positions of at least some of the poling domains are longitudinally shifted relative to normal periodic positions defined by the carrier periodicity;
• and
• the phase-modulated periodicity of the plurality of poling domains is such that the wavelength conversion device is characterized by at least two phase matching peaks that phase match the frequency doubling of the at least two switched fundamental spectral peaks such that an output beam that switches between at least two frequency-converted spectral peaks separated by at least 0.2 nm in wavelength is emitted from an output facet of the wavelength conversion device when the pump beam of the optical source is incident on an input facet of the wavelength conversion device;
• and
• the optical system is programmed to:
• generate at least a portion of a laser image on a projection surface by operating the laser for optical emission of encoded image data, the laser image comprising a plurality of successive image frames temporally separated by an inter-frame time;
• and
• control the laser such that the pump beam switches between the at least two fundamental spectral peaks during the inter-frame time.