9 results about "Optical breakdown" patented technology

In certain embodiments, an ophthalmic laser surgical system for treating a target tissue in an eye includes a target detection system and a laser device. The target tissue has an optical breakdown threshold. The target detection system directs detection beams along a detection beam path towards the target tissue in a vitreous of the eye, and determines a location of the target tissue within the vitreous. The laser device includes a femtosecond laser that generates subthreshold laser pulses that have a pulse energy below the optical breakdown threshold of the tissue. The laser device directs a laser beam comprising the subthreshold laser pulses along a laser beam path towards the target tissue.

A light-based skin treatment device is for treating skin by laser induced optical breakdown of hair or skin tissue. A focusing system has an exit focusing lens for focusing the incident light beam into a focal spot in the hair or skin tissue. This lens has a central aperture. This serves to reduce back-reflectance from the lens surface, which can cause damage to the focusing system.

An ophthalmic surgical system for monitoring incision performance includes a laser device, a camera, and a computer. laser device delivers a laser beam with a laser setting energy towards a target to create optical breakdowns in the target. The camera generates images of the optical breakdowns in the target. The computer instructs the laser device to create the optical breakdowns in the target to yield a test pattern. The test pattern comprises regions of optical breakdowns, where each region was created with a different laser setting energy. From the images, the computer identifies a lowest energy region with substantially continuous optical breakdowns, and designates the laser setting energy used to create the identified region as a threshold energy.

A catheter system (100) for treating a treatment site (106) within or adjacent to a blood vessel (108) includes a power source (124), a light guide (122), and a plasma target (242). In various embodiments, the light guide (122) receives power from the power source (124). The light guide (122) has a distal tip (244), and the light guide (122) emits light energy (243) in a direction away from the distal tip (244). The plasma target (242) is spaced apart from the distal tip (244) of the light guide (122) by a target gap distance (245). The plasma target (242) is configured to receive light energy (243) from the light guide (122) such that plasma bubbles (234) are generated at the plasma target (242). The power source (124) may be a laser, and the light guide (122) may be an optical fiber. The catheter system (100) may also be an inflatable balloon (104) surrounding the distal tip (244) of the light guide (122). The plasma target (242) may have a target surface (1672) that receives the light energy (243) from the light guide (122). The plasma target (242) may be formed from one or more of tungsten, tantalum, platinum, molybdenum, niobium, iridium, magnesium oxide, beryllium oxide, tungsten carbide, titanium nitride, titanium carbonitride, and titanium carbide.

A method for treating presbyopia of a crystalline lens using a femtosecond laser system, operated in a parameter regime characterized by extremely short pulse duration (below 100 fs) and low pulse energy (sub-μJ) of the pulses delivered to the lens tissue. The laser beam has a small focal volume in the tissue that is achieved by the short spatial pulse length, rather than defined by the large depth of focus resulting from the low numerical aperture of the laser beam. The laser energy density within the small focal volume (below 50 μm3) is sufficiently high to induce optical breakdown of the tissue, which reduces the Young's modulus of the lens to improve accommodation, thereby reducing presbyopia. Meanwhile, the total pulse energy in the focal volume is sufficiently low, resulting in small cavitation bubbles, which reduce light scattering and other damage or undesirable effects in the treated lens tissue.

A method for treating presbyopia of a crystalline lens using a femtosecond laser system, operated in a parameter regime characterized by extremely short pulse duration (below 100 fs) and low pulse energy (sub-µJ) of the pulses delivered to the lens tissue. The laser beam has a small focal volume in the tissue that is achieved by the short spatial pulse length, rather than defined by the large depth of focus resulting from the low numerical aperture of the laser beam. The laser energy density within the small focal volume (below 50 µm3) is sufficiently high to induce optical breakdown of the tissue, which reduces the Young's modulus of the lens to improve accommodation, thereby reducing presbyopia. Meanwhile, the total pulse energy in the focal volume is sufficiently low, resulting in small cavitation bubbles, which reduce light scattering and other damage or undesirable effects in the treated lens tissue.

The application provides a water jet guided high-power laser beam shaping method, system and application device, which comprises a laser, a beam expander and a focusing unit arranged in sequence, a beam shaping unit arranged between the beam expander and the focusing unit, and the beam shaping unit shapes the laser energy from Gaussian distribution into flat-top light distribution with uniform energy and long focal depth. The multi-focus light path energy focused after the beam shaping unit is uniform, the energy density of a single focus is reduced, optical breakdown is not caused in the coupling and transmission process of the water beam fiber due to the high energy density, and the total energy of the water beam coupled laser can be improved. The water jet guided high-power laser beam shaping method, system and application device can apply high-power density laser to water guided laser processing technology, improve the uniformity degree of the radial and / or axial light beam, effectively ensure the coupling efficiency and system robustness, and improve the processing quality and processing efficiency.

The invention relates to the technical field of cross-medium communication, and discloses a three-dimensional amplitude-frequency modulation method based on an optical breakdown mechanism, the method is applied to laser-induced sound cross-medium communication, and the method comprises the following steps: S1, obtaining a mapping relation between laser parameters and sound signal characteristics; and S3, carrying out signal demodulation based on the inverse mapping of the three-dimensional amplitude-frequency modulation. According to the invention, the relation between the optical breakdown internal physical process and the external multi-dimensional laser parameters and the influence of each parameter on the amplitude-frequency characteristic of the laser sound signal can be discussed by building a laser-induced sound physical process diagnosis platform, so that a novel signal modulation mode of modulation parameter design is expanded; by simultaneously modulating pulse laser parameters of three dimensions, namely laser pulse energy, pulse repetition frequency and pulse number, the amplitude-frequency characteristic of a laser sound signal can be effectively influenced, so that the information transmission rate is improved, and more efficient underwater signal transmission is realized.

An ophthalmic surgical system for monitoring incision performance includes a laser device, a camera, and a computer. laser device delivers a laser beam with a laser setting energy towards a target to create optical breakdowns in the target. The camera generates images of the optical breakdowns in the target. The computer instructs the laser device to create the optical breakdowns in the target to yield a test pattern. The test pattern comprises regions of optical breakdowns, where each region was created with a different laser setting energy. From the images, the computer identifies a lowest energy region with substantially continuous optical breakdowns, and designates the laser setting energy used to create the identified region as a threshold energy.