221results about How to "Reduce laser power" patented technology

A system for pulsed synchronized laser cutting of stents and/or other medical products includes a numerical controller and a machine for moving a tube of material during cutting. A pulsed fiber laser is configured to cut the tube into, for example, a stent, the numerical controller being in communication with the machine and configured to send movement control information to the machine. The numerical controller may also receive movement speed information from the machine. The numerical controller is also in communication with the pulsed fiber laser and is configured to send pulse control information to the pulsed fiber laser. The numerical controller is configured to cause average laser power to decrease by decreasing frequency of laser pulses as stent cutting speed decreases, and to cause average laser power to increase by increasing frequency of laser pulses as stent cutting speed increases.

In the rapid prototyping method of selective laser sintering, temperature gradients occur inside and between individual layers, leading to component deformation which is intolerable at least for high-quality components. The air of the invention is to provide a method for selective laser sintering, whereby the temperature inside the built-up particle cake is as homogeneous as possible. To this end, particles containing at least one material having a maximum softening temperature of approximately 70° C. are used.

A phase change optical recording medium is provided wherein the power of the laser beam per unit area required in the initialization is reduced. The optical recording medium has a phase change recording layer satisfying the relations: A.sub.I.ltoreq.8.0%, and C.sub.I/A.sub.I.gtoreq.3.0 when the medium is initialized with a light beam having a wavelength .lambda..sub.I, and said recording layer exhibits a reflectivity A.sub.I in amorphous region and a reflectivity C.sub.I in crystalline region at said wavelength .lambda..sub.I.

The invention relates to a method and apparatus for processing substrates, such as glass and semiconductor wafers. The method comprises directing to the substrate from a laser source a plurality of sequential focused laser pulses having a predetermined duration, pulsing frequency and focal spot diameter, the pulses being capable of locally melting the substrate, and moving the laser source and the substrate with respect to each other at a predetermined moving velocity so that a structurally modified zone is formed to the substrate. According to the invention, the pulse duration is in the range of 20-100 ps, pulsing frequency at least 1 MHz and moving velocity adjusted such that the distance between successive pulses is less than ⅕ of the diameter of the focal spot. The invention can be utilized, for example, for efficient dicing, scribing and welding of materials which are normally transparent.

The present invention utilizes a holographic optical forcing array for dynamic cellular probing and diagnostics. A holographic optical trapping system generates optical forces on objects so that deformations thereof may be quantified. In one embodiment, digital holography is used to generate an interference pattern, and an analysis thereof determines the phase profile which yields a measurement of the objects' shape deformation using only one image. In another embodiment, phase-stepped holography allows the phase profile of an object to be measured using only one image, by using a holographic optical element to make phase-shifted replicas of the beam in space. In another embodiment, the optical forcing array applies optical forces to beads placed on the objects' surface, deforming the objects. The beads' position is determined by applying Mie theory, and analysis thereof yields the three dimensional position of the beads, and a measurement of the deformation displacement on the objects' surface.

A thermally-assisted recording (TAR) head for recording data in data tracks of a TAR disk is supported on an air-bearing slider and includes the magnetic write pole, a near-field transducer (NFT), an optical waveguide that directs laser light to the NFT, and an electrically conductive layer between and in contact with the NFT and the write pole. The NFT has an output tip having a generally triangularly-shaped end at the slider's air-baring surface (ABS). The electrically conductive layer is located between the NFT and the write pole and contacts both the NFT output tip and the write pole. The electrically conductive layer has a contact edge that is generally parallel with the ABS but recessed from the NFT output tip end and a cross-track width greater than the cross-track width of the NFT output tip end.

A laser and double-electric-arc double-faced composite welding method for a T-type joint relates to a welding method for laser and electric arc composite welding, and particularly relates to applying the laser and the double-electric-arc double-faced composite welding to a workpiece with a T-type joint to be welded. The invention aims to solve the problems that the single laser penetration welding has strict requirement to the seam fit-up gap and smaller fusion diameter of the faying surface, which results in low shear strength of the seam; and the laser wire filling welding or the double-beam laser synchronous welding process has strict requirement and high cost in the prior T-type joint welding. The laser beams are vertically incident for penetration welding from the top surface of a top plate along the seam formed by the contact of a vertical slab and the top plate of the T-type joint, at the same time, a first electric arc welding gun and a second electric arc welding gun carry out synchronous welding from the two sides of the seam, and the first electric arc welding gun and the second electric arc welding gun are remained to be arranged symmetrically on the left and the right sides of the vertical slab. Compared with the single laser welding, the composite welding method of the invention has the advantages that the capacity usage ratio is improved by more than 30%, the welding speed is increased by more than twice, and the welding efficiency is improved by two to three times.

The invention provides a method for removing laser welding pores of a medium-thick D406A ultra-high-strength steel, and aims at solving the problem of pores of a medium-thick D406A ultra-high-strength steel plate in welding. The method comprises the following steps: grinding and cleaning a part to be welded; assembling; setting backing weld and filling weld process parameters; controlling the welding process parameters through a robot integration system; arcing through TIG (Tungsten Inert Gas Welding) electric arc; stabilizing the electric arc for 1 to 2 seconds; controlling a laser to emit laser; finally controlling a robot to drive a laser working head and a TIG welding gun to work together to finish the welding process. According to the method, different pore inhibiting measures are carried out for backing weld and filling weld.

The invention discloses a bifocus laser and InFocus arc hybrid welding method, and relates to a welding method. The method includes the steps that (1) a to-be-welded workpiece is polished or washed; (2) the spot diameter is set to range from 0.1 mm to 0.5 mm, and the defocusing amount ranges from -3 mm to +3 mm; (3) welding parameters are set, wherein the arc current ranges from 50 A to 900 A, an included angle formed between a welding gun and the vertical direction ranges from 25 degrees to 55 degrees, the welding speed ranges from 100 mm/min to 1000 mm/min, the wire feeding speed ranges from 100 mm/min to 600 mm/min, the protection gas is inert gas, and the flow of the protection gas ranges from 15 L/min to 30 L/min; and (4) a switch is started, and laser-InFocus arc welding is carried out. According to bifocus lasers and InFocus, as the InFocus arc fusion depth is larger, and a key hole can be formed through welding, when a medium-thickness plate is welded, the lasers can directly act on the bottom of the key hole generated by the InFocus arc, and the fusion depth is continuously increased.

The invention relates to a fundus optical full-field microangiography imaging device and method. The device comprises a fundus illumination optical path, a fundus imaging optical path, a synchronous triggering source and a data processing system, wherein the fundus illumination optical path and the fundus imaging optical path are synchronously triggered by the synchronous triggering source; the fundus illumination optical path comprises a light source controller, a laser light source, a beam expanding lens, a beam splitter lens and an eye piece objective lens which are sequentially connected; and the fundus imaging optical path comprises an eye piece objective lens, a beam splitter lens, an imaging ocular lens, a lens and a COMS (Complementary Metal Oxide Semiconductor) camera which are sequentially connected. The device and the method have the advantages that the light source gives out laser at the same frequency as the sampling frame rate of the camera; the realization of the fundus microvessel imaging is ensured; and meanwhile, the laser power is reduced, so that the value reaches the range capable of being borne by human eyes. The method and the device can realize the fundus optical full-field microangiography imaging. The method has the advantages that a contrast agent is not needed; the resolution ratio, the signal-to-noise ratio and the detection depth are high; and the fundus blood capillary can be rebuilt.

A laser surface treatment for reducing reflection loss on the surface of an optical material is provided. A metal film is formed on the surface of the optical material, and then the metal film is removed from the optical material by irradiation of an ultra-intense short-pulse laser beam having a pulse width of 1 femtosecond to 100 picoseconds, so that a fine periodic structure is formed on the surface of the optical material exposed by the removal of the metal film. The obtained fine periodic structure has asperities with a periodic interval of preferably 50 to 1000 nm, which can be controlled by changing the laser energy density.

The invention relates to a connecting method, in particular to a connecting method assisted by electro-magnetic induction synchronous preheating and based on laser additive manufacturing. The problems that Ti-Al system intermetallic compound materials, high-temperature alloy, aluminum alloy and the like are sensitive to laser welding cracks, materials serious in laser reflection are prone to defects like cracks during welding, and the laser utilization rate is small are solved. The method includes the steps that a workpiece to be welded is machined, ground and cleaned; process parameters are set, and welding is carried out. An electro-magnetic induction coil serves as a preheating heat source, the crack sensitivity tendency of the materials in the welding process is relieved, the defects that the materials are low in laser adsorption rate, large in energy consumption in the welding process and the like are effectively relieved, and the laser utilization rate is improved. Meanwhile, the welding joint and peripheral materials are heated in an induction mode, the temperature gradient of the area around the welding joint in the welding process is reduced, the micro structure after welding can be effectively improved, and the performance of a welding connector is improved.

The invention relates to a reservoir dam deformation monitoring method and system. The monitoring method includes the following steps that: 1) a reservoir dam deformation monitoring device is set; 2) the initial circular light spot images of each reference point are obtained; and 3) reservoir dam deformation monitoring is carried out. The reservoir dam deformation monitoring system includes a laser emitting device, reference point detecting devices and a main control system; the laser emitting device is arranged at one end of a dam and is used for emitting collimating laser light adopted as a reference line; a plurality of reference points with equal intervals are arranged one a ray with the laser emitting device adopted as an end point; one reference point detecting device is arranged at each reference point; the reference point detecting devices are used for detecting the subsidence and horizontal displacement of the dam; and the main control system is connected with the laser emitting device and the reference point detecting devices through a wireless communication mode and is used for transmitting detection commands, receiving detected data and performing analysis processing on the detected data. With the reservoir dam deformation monitoring method and system of the invention adopted, the automatic detection of the subsidence and horizontal displacement of the dam can be realized, the measurement accuracy of the reservoir dam is improved, and monitoring costs can be reduced.

The invention relates to a quick preparing method for a large-area surface Raman spectrum enhancing monocrystalline silicon substrate and belongs to the field of SERS substrate preparing. The quick preparing method comprises the steps that the surface of monocrystalline silicon is covered with a microballoon array which is periodically and densely arranged; microballoon left on the surface is removed through laser scanning or irradiating; the monocrystalline silicon is immersed into a sodium hydroxide water solution including alcohol, corrosion is carried out for 10-30 s in the environment with the water bath temperature ranging from 70 DEG C to 80 DEG C, the monocrystalline silicon is taken out and cleaned with deionized water, and the monocrystalline silicon with the microstructure array is obtained, wherein in the water solution, the sodium hydroxide accounts for 5%-10% by mass, and alcohol accounts for 8%-10% by mass; silver film deposition is carried out on the surface of the corroded monocrystalline silicon through magnetron sputtering, and the deposition thickness ranges from 50 nm to 200 nm. By means of the quick preparing method, the periodic and uniform microstructure array can be quickly, easily and conveniently prepared, and the performance of an SERS substrate can be controlled by controlling the morphology dimension feature of the microstructure array and the thickness of a silver film. Meanwhile, the method is high in reproducibility and low in cost, and prepared SERS substrate is stable in performance and capable of being repeatedly used.

Disclosed are an information reproduction method and an information recording medium that allow reproducing information below a diffraction limit. A recording layer formed with recording marks consisting of a nucleation inducer and a reading layer are provided. When a reading beam is irradiated, a predetermined area of the reading layer is crystallized based on the recording mark of the recording layer such that the area is magnified to a size larger than the recording mark, and information is thus reproduced. Information of the recording marks below the diffraction limit can be reproduced without using a special information reproduction apparatus.

Provided is a laser joining apparatus for joining a metal material and a resin housing made from a thermoplastic resin, wherein the laser joining apparatus enhances the efficiency of heat conduction and reduces the output of the laser beam. A joining apparatus that heat-joins the joint surfaces of a resin housing (7) and a metal material (3) by applying a laser to the surface of the metal material (3) on the opposite side of the joint surface, wherein the resin housing (7) and metal material (3) are positioned and fixed by an upper mold (1) and a lower mold (2) and the joint surfaces of the resin housing (7) and metal material (3) are brought into close contact by pressing the upper mold (1). At this time, the metal material (3) is preheated by a heater (8). A laser beam is applied thereafter from a hole (1a) in the upper mold (1). The efficiency of heating the metal material (3) using the laser can be enhanced, the laser output can be reduced, and the cost of joining can be vastly reduced by heating the resin housing (7) and metal material (3) to a predetermined temperature using the heater (8) and pressurizing the joint surfaces using the upper mold (1) and lower mold (2).

Provided is a laser beam apparatus for sealing a first substrate and a second substrate by irradiating a sealant between the first substrate and the second substrate using a laser beam, the laser beam apparatus including a controller, wherein the controller is configured to defocus the laser beam and to move a scanning central axis of the laser beam across a sealing path of the sealant.