METHOD AND DEVICE FOR FORMING PRECISION HOLES IN OPTICALLY TRANSPARENT FILM WITH ULTRA-SHORT LASER RADIATION PULSE Russian patent published in 2015 - IPC B23K26/38 

FIELD: physics.

SUBSTANCE: film is placed in a liquid medium which is transparent for laser radiation, having a refraction index of not less than 1.5 and pulses are focused by an optical system with a lens with a numerical aperture of not less than 0.33 or the film is placed behind a plate made of material which is transparent for laser radiation, having a refraction index of not less than 1.5 and pulses are focused by an optical system with a lens with a numerical aperture of not less than 0.5. The film is placed at a distance from the lens which is greater than the focal distance of said system during paraxial approximation. Said film is placed in a focal constriction with overlapping of the film and a hole is formed in said film. The energy of the ultra-short laser radiation pulse is set based on a condition of providing energy density of the laser radiation which is higher than the breakdown threshold of the material of the film in the region of the focal constriction.

EFFECT: device enables to form a hole with a diameter of up to 5 mcm in a film with thickness of up to 100 mcm using a single ultra-short laser radiation pulse.

7 cl, 5 dwg