Abstract: A method for suppressing the blockage of a miniature Joule-Thomson cryocooler based on a photothermal effect includes: determining form and temperature of a trace impurity contained in a working medium of the cryocooler according to an operating condition of the cryocooler, and selecting an optimal wavelength of an electromagnetic wave based on the form and temperature of the impurity and a peak of absorption spectrum of the impurity to electromagnetic waves; estimating, via a prediction model of input power of the electromagnetic wave, an initial value of input power corresponding to the optimal wavelength; and emitting an electromagnetic wave with the power W by a laser capable of generating the optimal wavelength in a direction perpendicular to a passage of a throttle in the cryocooler to eliminate the impurity in the passage of the throttle.

Abstract: A miniature Joule-Thomson cryocooler operating at liquid helium temperatures includes an integral structure formed by welding at least three base plates sequentially superposed, an outermost base plate in the at least three base plates is configured as a cover plate and configured to seal the rest of the at least three base plates, the rest of the at least three base plates is configured as a first-stage cooling circulator, a second-stage cooling circulator and a third-stage cooling circulator respectively, the first-stage cooling circulator, the second-stage cooling circulator and the third-stage cooling circulator have a first-stage working fluid, a second-stage working fluid and a third-stage working fluid respectively, the first-stage cooling circulator is configured to precool the second-stage working fluid and the third-stage working fluid through the first-stage working fluid, and the second-stage cooling circulator is configured to precool the third-stage working fluid through the second-stage working

Abstract: A method for suppressing the blockage of a miniature Joule-Thomson cryocooler based on a photothermal effect includes: determining form and temperature of a trace impurity contained in a working medium of the cryocooler according to an operating condition of the cryocooler, and selecting an optimal wavelength of an electromagnetic wave based on the form and temperature of the impurity and a peak of absorption spectrum of the impurity to electromagnetic waves; estimating, via a prediction model of input power of the electromagnetic wave, an initial value of input power corresponding to the optimal wavelength; and emitting an electromagnetic wave with the power W by a laser capable of generating the optimal wavelength in a direction perpendicular to a passage of a throttle in the cryocooler to eliminate the impurity in the passage of the throttle.