摘要:
A selective aperture for a laser delivery system for providing incision, ablation and coagulation. A laser crystal disposed between two reflective surfaces forms a laser beam. An aperture member positioned between the laser crystal and one of the reflective surfaces includes a substantially circular aperture for passing the laser beam. The size of the aperture is selectively adjustable. The aperture member has a plurality of apertures of various different sizes and is rotatable about an axis of rotation. The axis of rotation is parallel to the longitudinal axis of the laser crystal. By appropriately rotating the aperture member, a selected one of the apertures is positioned to pass the laser beam. A stepper motor and flexible shaft are utilized for rotating the aperture member. At least one of the apertures is surrounded by a beveled portion of the rotatable member. Alternatively, two lasers with different size fixed apertures could be utilized and directed to a common surface. According to an aspect of the invention, an articulated arm is provided along with one or more refocussing optics for refocussing the laser beam as it travels through the arm. According to another aspect, a second laser source is provided along with a galvanometer for directing each of two laser beams to a surface to be treated. Such an arrangement provides exceptional versatility and control over the beam emitted. According to an another aspect, the aperture for a single laser source is rapidly changed during the performance of a procedure. By rapidly switching between forming an incision and cauterizing, an incision can be cauterized while being made.
摘要:
An applicator is configured with an optical window formed from a first and a second lens section. The applicator is configured for modulating the temperature of a working surface while simultaneously exposing the working surface to a radiation source. The first and the second lens sections form boundaries of a medium cavity for channeling a temperature regulating medium which is preferably a cooled liquid medium. The first lens section has an outer lens and an inner lens which are preferably separated by a distance in the range of 0.1 to 1.0 cm and form boundaries of an insulating region. In a preferred method, a temperature regulating medium is circulated through the medium cavity while exposing a target tissue to laser radiation through the optical window. The insulating region helps reduce fogging of the optical window thereby improving visibility through the window and reducing scattering of the laser radiation. Preferably, the insulating region is under vacuum. Alternatively, the insulating region is configured to channel a second temperature regulating medium. The applicator and system of the instant invention are preferably configured for exposing dermis to a pulsed laser source while simultaneously cooling dermis during procedures to remove hair or treat the cutaneous vascular lesions.
摘要:
A system for and method of performing laser assisted surgery is disclosed. Laser radiation is preferably delivered to a target area of tissue using a Er:YAG laser source. The laser radiation is delivered to the target area in bursts of laser radiation comprising sets of laser pulses. The bursts of laser radiation are preferably delivered to the target area at a repetition rate in a range of 10 to 40 Hz and with sufficient pulse fluences to cut and/or dissect. In accordance with a preferred embodiment, interchangeable and flexible endo-probes are configured with shield features. The shield features control the emission of laser radiation from the optical fiber while bending the flexible probes allow surgeons to access a range of approach angles for the laser treatment of biological tissue enclosed or within a cavity of a body. The probes can also be configured with mechanical cutters or other structures which allow for the mechanical manipulation of tissue during laser treatment. The system for and method of performing laser assisted surgery is particularly well suited for treating fibrous and/or fibro-vascular membranes (FVMs) on ophthalmic tissue during vitreoretinal surgery.
摘要:
A system for and method of performing laser assisted surgery is disclosed. Laser radiation is preferably delivered to a target area of tissue using a Er:YAG laser source. The laser radiation is delivered to the target area in bursts of laser radiation comprising sets of laser pulses. The bursts of laser radiation are preferably delivered to the target area at a repetition rate in a range of 10 to 40 Hz and with sufficient pulse fluences to cut and/or dissect. In accordance with a preferred embodiment, interchangeable and flexible endo-probes are configured with shield features. The shield features control the emission of laser radiation from the optical fiber while bending the flexible probes allow surgeons to access a range of approach angles for the laser treatment of biological tissue enclosed or within a cavity of a body. The probes can also be configured with mechanical cutters or other structures which allow for the mechanical manipulation of tissue during laser treatment. The system for and method of performing laser assisted surgery is particularly well suited for treating fibrous and/or fibro-vascular membranes (FVMs) on ophthalmic tissue during vitreoretinal surgery.
摘要:
A laser system employing one or more mirror sets having substantially astigmatism-free focusing power sufficient to maintain a desired laser beam diameter, for example, to compensate for thermally-induced distributed lensing. In one class of preferred embodiments, the invention is a high power gas laser system having a folded optical cavity with a periodic intracavity refocusing means to compensate for distributed negative thermal lensing in the hot plasma that comprises the active medium, and thus maintain a substantially constant beam diameter throughout the optical cavity. The periodic intracavity refocusing means preferably includes a corner mirror set (including at least one curved mirror and at least one other mirror) at each corner of the folded optical cavity. In one preferred embodiment, each corner mirror set is a mirror pair including a spherical mirror and cylindrical mirror. In another preferred embodiment, each corner mirror set comprises three mirrors (including three spherical mirrors, or two spherical mirrors and a planar mirror). In another class of preferred embodiments, the inventive focusing mirror sets are not included within the optical cavity of a high power laser, but instead, one or more such focusing mirror sets are included within the output beam delivery optical components of a high power laser. For example, one of the inventive focusing mirror sets may replace a conventional lens to direct the output beam of a high power laser system along a desired path and maintain a desired beam diameter.
摘要:
A servo alignment method and apparatus for maintaining laser beam alignment. An operating parameter of the laser (such as output beam power) is measured, and error signals are generated from the measured operating parameter signal for controlling the laser beam alignment. In one class of embodiments, modulation signals are supplied to an intra-cavity component of a laser system to modulated the beam path. The beam path may be modulated by reciprocating a laser resonator mirror about a mirror axis or two substantially orthogonal mirror axes. In the latter case, the mirror may be vibrated about the axes either alternately (first about one axis and then about the other) or simultaneously. In embodiments in which an intra-cavity component is modulated, the laser operating parameter is measured during such modulation, the measured operating parameter signal is demodulated (preferably by multiplication in a mixer with a selected frequency component of the modulation signal currently being asserted), and error signals are generated from the demodulated signal for controlling the laser beam alignment.
摘要:
A reader-scanner system using a laser as a source of a narrow beam of light and having optical means for directing the light beam from the laser to a scan target area with the optical means generating a pattern comprising a series of intersecting diagonal and horizontal lines relative to the path of objects which pass through the scan target area, with sequential scan pattern sets in the scan target area displaced in the direction of oncoming objects from the previous scan pattern set, with each of the lines defining each scan pattern set approaching the scan target area from a different direction and wherein the optical path of the incoming scan lines is shared by the reflected light as it travels to the system's optical detector.
摘要:
A servo alignment method and apparatus for maintaining laser beam alignment. An operating parameter of the laser (such as output beam power) is measured, and error signals are generated from the measured operating parameter signal for controlling the laser beam alignment. In one class of embodiments, modulation signals are supplied to an intra-cavity component of a laser system to modulate the beam path. The beam path may be modulated by reciprocating a laser resonator mirror about a mirror axis or two substantially orthogonal mirror axes. In the latter case, the mirror may be vibrated about the axes either alternately (first about one axis and then about the other) or simultaneously. In embodiments in which an intra-cavity component is modulated, the laser operating parameter is measured during such modulation, the measured operating parameter signal is demodulated (preferably by multiplication in a mixer with a selected frequency component of the modulation signal currently being asserted, and error signals are generated from the demodulated signal for controlling the laser beam alignment.
摘要:
A laser system employing one or more mirror sets having substantially astigmatism-free focusing power sufficient to maintain a desired laser beam diameter, for example, to compensate for thermally-induced distributed lensing. In one class of preferred embodiments, the invention is a high power gas laser system having a folded optical cavity with a periodic intracavity refocusing means to compensate for distributed negative thermal lensing in the hot plasma that comprises the active medium, and thus maintain a substantially constant beam diameter throughout the optical cavity. The periodic intracavity refocusing means preferably includes a corner mirror set (including at least one curved mirror and at least one other mirror) at each corner of the folded optical cavity. In one preferred embodiment, each corner mirror set is a mirror pair including a spherical mirror and cylindrical mirror. In another preferred embodiment, each corner mirror set comprises three mirrors (including three spherical mirrors, or two sperical mirrors and a planar mirror). In another class of preferred embodiments, the inventive focusing mirror sets are not included within the optical cavity of a high power laser, but instead, one or more such focusing mirror sets are included within the output beam delivery optical components of a high-power laser. For example, one of the inventive focusing mirror sets may replace a conventional lens to direct the output beam of a high power laser system along a desired path and maintain a desired beam diameter.
摘要:
The reflectors in a laser are mounted in precise axial alignment by means of an elongated mounting structure made of a material of low thermal coefficient of expansion which serves to prevent reflector misalignment due to temperature changes in the laser, the elongated mounting structure also including an associated member made of a material of high thermal conductivity which serves to direct heat away from the elongated mounting structure along the length, further reducing any temperature effects thereon. In addition, a kinematic mounting structure is provided for further enhancing the alignment stability characteristics of the plasma tube and resonator structure.