31results about How to "Reduce laser power density" patented technology

The invention discloses a high-energy laser beam expanding and absorbing device which comprises a laser beam expanding cone, an energy absorption cavity, a front panel and a fixing plate, wherein the energy absorption cavity adopts a hollow cylinder; the front panel is arranged at a laser incident end of the energy absorption cavity, and the fixing plate is arranged at the rear end of the energy absorption cavity and used for fixing the laser beam expanding cone; and the laser beam expanding cone comprises a pointed beam expanding cone, at least two spherical beam expanding cones and cylinder transition sections which are arranged in the laser incident direction sequentially, and radii of cylinders of the cylinder transition sections are increased gradually in the laser incident direction. The laser beam expanding cone simultaneously realizes beam expanding of incident laser beams in the length direction and the circumference direction of the absorption cavity, and effectively reduces the power density of laser shot to a heat absorption cylinder by the laser beam expanding cone; and by means of the high-energy laser beam expanding and absorbing device, absorption and conduction of hundred thousand joules to a megajoule of high-power laser energy of continuous waves are realized, the measuring accuracy of an energy meter is improved greatly, and the device has wide applicability.

A method for cutting a semiconductor wafer by generating a crack within the wafer, and a system thereof, are provided. The method comprises irradiating a laser beam towards a surface of the wafer and converging the laser beam to form a focal point so that a focal volume defined by the focal point and a boundary of the laser beam within the wafer is formed. Energy encompassed within the focal volume causes the wafer located at the periphery of the focal volume to contract faster than the wafer located within the focal volume, thereby generating a crack within the wafer.

The invention discloses a tunable slab laser, and belongs to the technical field of lasers. The tunable slab laser aims at improving the output power of a small tunable slab laser. According to the technical scheme, the tunable slab laser comprises a vacuum cavity. A laser path folding system is transversely arranged in the vacuum cavity and comprises a reflection-type blazed grating, a total-reflection concave mirror, a total-reflection convex mirror and a partial-reflection output mirror. After frequency selecting is carried out on oscillation lasers through the blazed grating, the oscillation lasers sequentially pass through the total-reflection concave mirror and the total-reflection convex mirror and are reflected by the total-reflection concave mirror and the total-reflection convex mirror, and finally the reflected lasers are output through the partial-reflection output mirror. The structure is mainly used for the laser, the quality of output laser beams of the laser can be guaranteed, the power density on the grating face can be reduced, and larger power output can be achieved.

The invention provides a laser cutting method of tempered glass. The method comprises the following steps: (1) distributing a bilateral cooling jet assisted laser cutting beam at the to-be-cut starting position of tempered glass; (2) performing laser cutting along the to-be-cut path of the tempered glass, wherein the processing process parameters comprise a power density P and a cutting speed value v; and (3) closing laser when the laser cutting beam approaches the destination of the to-be-cut path of the tempered glass, and closing bilateral strip cooling jet flow when the bilateral strip cooling jet flow reaches the destination of the to-be-cut path of the tempered glass. By utilizing the bilateral cooling jet forced cooling method, bilateral pulling force is formed in the original irridation position of the slit center, so that a steep tensile peak delta' pulling occurs in the center, the tempered glass is cut according to the cutting track when the cutting speed value v is more than a macro-cracking travelling speed of the tempered glass, and the technical problem that current tempered glass cannot be cut can be solved.

The invention disclose a total absorption superlaser energy meter which comprises a reflection cone and an absorption cavity, wherein the generatrix of the reflection cone is arc-shaped, the absorption cavity is formed by sealed connection of a base plate, an inner lateral plate, an absorption cylinder and a cover plate, the whole structure of the absorption cavity is concave, the wall of the absorption cylinder is arranged on the light path of a superlaser beam after the superlaser beam is reflected through the reflection cone, and the absorption cylinder is located behind the reflection cone in the front and back direction. According to the total absorption superlaser energy meter, the incident collimated light beam is reflected onto the wall of the absorption cylinder in an axial and circumferential two-dimensional beam expansion mode, the power density of laser irradiating on the wall of the absorption cylinder is reduced greatly, the light receiving area of the reflection cone is increased at the same time, and the laser irradiation bearing capacity of the reflection cone is improved; furthermore, due to the adoption of the cavity structure, the probability that the reflection cone is polluted by dust is effectively reduced, and meanwhile, the exit escape rate of laser is reduced and measurement accuracy of the energy meter is improved.

The invention provides a high-energy laser semi-integrating-sphere array attenuator, which comprises a front panel arranged along a laser incident direction, a back panel and a plurality of attenuation units, wherein the attenuation units comprise wide-angle sampling taper holes arranged on the front panel, semi-sphere cavities arranged on the back panel, and laser emergent holes which are arranged on the edges of the semi-sphere cavities and are vertical to the back panel; the positions of the wide-angle sampling taper holes are corresponding to the positions of the semi-sphere cavities one to one; and the wide-angle sampling taper holes and the laser emergent holes are respectively arranged on the two sides of the semi-integrating-sphere cavities. In the attenuator provided by the invention, laser is coupled into the semi-sphere cavities via the wide-angle sampling taper holes, is absorbed and diffuse-reflected by the semi-sphere cavities, and then is ejected from the laser emergentholes, large amplitude attenuation of laser power density is realized, and the requirement of attenuation sampling during oblique incidence of the laser can be satisfied.

A frequency doubling laser generating device, comprising: sequentially connected single-frequency lasers, phase modulators, laser amplifiers, space isolators and frequency doubling devices, and also includes a signal generator, which generates radio frequency or pseudo-random signals for use in Drive the phase modulator to modulate and output a single-frequency laser with a phase amplitude of Nπ. After the single-frequency laser is amplified by the laser amplifier, it is injected into the frequency doubling device through the space isolator to obtain the laser phase Single-frequency or narrow-linewidth frequency-doubled light with a modulation amplitude of 2Nπ, where N is an odd number. Since the phase modulator can achieve phase modulation in a wide wavelength range, and the high-power low-frequency fundamental frequency light obtained through the laser amplifier can be frequency-multiplied to obtain single-frequency or narrow-linewidth frequency-multiplied light, the structure is simple and With advantages such as flexible design, it provides a new technical solution for high-power, high-stability single-frequency or narrow-linewidth laser frequency doubling, and has high practical value and application prospects.