A variable wavelength light emitter comprising:
- at least one light source;
- a wavelength changing film spaced apart from the at least one light source by a predetermined distance and comprising a plurality of regions, each of the plurality of regions corresponding to each of, each column of, or each row of the at least one light source;
- a driving motor configured to change an irradiation region of the wavelength changing film illuminated by the light source;
- and
- a processor configured to control an operation of the driving motor to adjust a wavelength of output light from the wavelength changing film,
- wherein the plurality of regions of the wavelength changing film are separated either in rows or in columns, and the driving motor moves the wavelength changing film either in a row direction or in a column direction to change the irradiation region of the wavelength changing film illuminated by the light source.