摘要:
A scanning optical system for delivering electromagnetic radiation onto tissue to be treated is cooperative with a lightguide or optical fiber. Radiation to be delivered is provided by a source thereof via the optical fiber. The optical system includes an optical projection arrangement comprising a plurality of lenses cooperatively arranged with the lightguide. A first of the lenses is arranged to receive radiation emerging from the lightguide. The beam of radiation is passed through the projection arrangement to form a treatment spot the radiation on the tissue. Scanning is effected by causing relative motion between the exit-end of said lightguide and at least the first lens, transverse to the optical axis of the projection arrangement. The treatment spot undergoes a related transverse motion over the tissue. In one example scanning is effected by moving the first lens with the lightguide fixed. The first lens is moved using an arrangement of piezo-electric actuators.
摘要:
A semiconductor gain-structure functions as a gain-element in a laser-resonator. The gain-structure is bonded to a diamond heat-spreader that is peripherally cooled by a heat-sink configured to allow access to the gain-structure by laser-radiation circulating in the laser-resonator. In one example, the gain-structure is used as a transmissive gain-structure in a traveling-wave ring-resonator. In another example, the gain-structure surmounts a mirror-structure which functions as an end-mirror of a standing-wave laser-resonator.
摘要:
An optical pulse-shaper includes a prism, a delay line having positive optical power and a reflective spatial light modulator. In one arrangement the delay line has a selectively variable optical path length for accommodating pulses of different spectral bandwidth and positive optical power is provided by a concave mirror. In another arrangement, the delay line includes a zoom-mirror arranged to provide selectively variable optical power for accommodating pulses of different spectral bandwidth.
摘要:
An optically pumped semiconductor pumped optical parametric oscillator (OPS-pumped OPO) includes an OPS laser resonator and an OPO resonator A portion the OPS laser resonator axis and the OPO resonator axis are collinear. An optically nonlinear crystal is located in the coaxial portion of the resonators and arranged to frequency divide fundamental radiation generated in the OPS laser resonator into signal and idler radiations. In one arrangement, the OPO laser resonator is also an OPS resonator and is arranged to generate radiation at the wavelength of the signal radiation, with the idler radiation having the difference-frequency wavelength of the signal and fundamental radiations
摘要:
A multilayer semiconductor laser includes a substrate on which is formed a semiconductor multilayer heterostructure divided into a plurality of electrically pumped regions and an elongated optically pumped region. The electrically pumped regions generate and deliver optical pump radiation laterally into the elongated optically pumped region. Output radiation is generated and delivered by the optically pumped region.
摘要:
An optically pumped semiconductor laser includes an active ring-resonator having two or more optically pumped semiconductor (OPS) structures each including a mirror-structure and a multilayer gain-structure. The mirror-structures serve as fold mirrors for the resonator axis. An optically nonlinear crystal may be included in the ring-resonator for generating second-harmonic radiation from fundamental radiation generated in the resonator. Another optically nonlinear crystal may be provided for generating third-harmonic or fourth-harmonic radiation from the second-harmonic radiation. In one example, including a third-harmonic generating crystal, a passive ring-resonator partially coaxial with the active ring-resonator is provided for circulating second-harmonic radiation to provide resonant amplification of the second-harmonic radiation for enhancing third-harmonic conversion. Apparatus for automatically maintaining the passive ring-resonator in a resonant condition for the second-harmonic radiation is disclosed.
摘要:
Apparatus for projecting a line of light includes a linear array of diode-lasers arranged in a diode-laser bar. The apparatus includes an optical system. Components of the system include a plurality of lenses and array of cylindrical microlenses having the same spacing as diode-lasers in the diode-laser array. The microlens array is spaced at a distance from the diode-laser bar and aligned with the diode-laser bar such that the front focal plane of the microlens array is between the diode-laser bar and the microlens array. The optical system components are configured and arranged to project overlapping elongated images in a predetermined plane. The overlapping images form the line of light. The elongated images are images of cross-sections of beams from the diode-lasers where the beams are intersected by the front focal plane of the microlens array.
摘要:
Negative Group-delay-dispersion mirror (NGDD-mirror) multilayer structures include a generally-orderly arrangement of layers or groups of layers in which the function of certain individual layers or groups of layers can be recognized and defined. The structures are broadly definable as a rear group of layers which are primarily responsible for providing a desired reflection level and reflection bandwidth together with a low and smoothly varying reflection phase-dispersion, and a front group of layers which are primarily responsible for producing high reflection phase-dispersion necessary for providing a desired NGDD level and bandwidth. The front group of layers relies on multiple resonant trapping mechanisms such as two or more effective resonant-cavities, employing one or more sub-quarter-wave layers to shape the phase-dispersion for providing a substantially-constant NGDD. In certain embodiments of the structures, a base layer or substrate of a highly-reflective metal can be used to reduce the number of dielectric layers needed to provide high reflectivity.
摘要:
The present invention is directed to an anti-reflection and UV rejection coating. The coating comprises at least eight layers wherein adjoining layers alternate between high and low refractive index materials. The layer adjacent an article on which the coating is formed has a high refractive index greater than about 2.10 at a wavelength of about 520 nanometers and greater than about 2.50 at a wavelength of about 330 nanometers. The index of refraction of the low refractive index material is less than about 1.50 at a wavelength of about 520 nanometers. The two layers of low refractive index material nearest the article each have an optical thickness at a wavelength of about 330 nm of about one-quarter wavelength.
摘要:
A multilayer, thin-film, broad-band, anti-reflection structure applicable to transparent substrates. The present invention makes use of the UV absorption properties of zinc oxide to provide UV rejection for wavelengths shorter than 380 nm, while providing anti-reflection properties in the visible region of the spectrum. The structure provides a reflection value less than 0.25% in the visible region of the spectrum, and blocks 99 percent of UV radiation below 380 nm.