A wavelength conversion device (100, 200, 600, 700), comprising: a wavelength conversion layer (110, 210, 610, 710) for absorbing an excitation light and generating a converted light; a box (120, 220, 620, 720), which includes a first area (121, 221, 621, 721) for transmitting the excitation light to the wavelength conversion layer (110, 210, 610, 710) and a second area (122, 222, 622, 722) for transmitting the converted light, and further includes an air inlet (124, 224, 624, 724) and an air outlet (123, 223, 623, 723); a conduit (130, 230, 630, 730), disposed outside of the box (120, 220, 620, 720), for connecting the air inlet (124,224, 624, 724) and the air outlet (123, 223, 623, 723), which is adapted to cooperate with the box (120, 220, 620, 720) to seal the wavelength conversion layer (110, 210, 610, 710) inside the box (120, 220, 620, 720); a heat exchanger, for lowering a temperature of the air inside the conduit(130, 230, 630, 730); an air circulation device (150, 250, 350, 450, 550, 650, 750), disposed in the sealed space formed by the box (120, 220, 620, 720) and the conduit (130, 230, 630, 730), for driving air exchange between the box (120,220, 620, 720) and the conduit (130, 230, 630, 730), and characterized by a drive device (660, 760), for driving the wavelength conversion layer (610, 710), so that a light spot formed by the excitation light on the wavelength conversion layer (610, 710) acts on the wavelength conversion layer (610, 710) along a predetermined path, wherein the air circulation device includes a plurality of blades, which are affixed to the drive device, wherein the plurality of blades and the wavelength conversion layer are driven by the drive device to move synchronously. a wavelength conversion layer (110, 210, 610, 710) for absorbing an excitation light and generating a converted light; a box (120, 220, 620, 720), which includes a first area (121, 221, 621, 721) for transmitting the excitation light to the wavelength conversion layer (110, 210, 610, 710) and a second area (122, 222, 622, 722) for transmitting the converted light, and further includes an air inlet (124, 224, 624, 724) and an air outlet (123, 223, 623, 723); a conduit (130, 230, 630, 730), disposed outside of the box (120, 220, 620, 720), for connecting the air inlet (124,224, 624, 724) and the air outlet (123, 223, 623, 723), which is adapted to cooperate with the box (120, 220, 620, 720) to seal the wavelength conversion layer (110, 210, 610, 710) inside the box (120, 220, 620, 720); a heat exchanger, for lowering a temperature of the air inside the conduit(130, 230, 630, 730); an air circulation device (150, 250, 350, 450, 550, 650, 750), disposed in the sealed space formed by the box (120, 220, 620, 720) and the conduit (130, 230, 630, 730), for driving air exchange between the box (120,220, 620, 720) and the conduit (130, 230, 630, 730), and characterized by a drive device (660, 760), for driving the wavelength conversion layer (610, 710), so that a light spot formed by the excitation light on the wavelength conversion layer (610, 710) acts on the wavelength conversion layer (610, 710) along a predetermined path, wherein the air circulation device includes a plurality of blades, which are affixed to the drive device, wherein the plurality of blades and the wavelength conversion layer are driven by the drive device to move synchronously.