Coherent, Inc.

Spectra-physics Gmbh

Acle V Hicks

Ralph Bradford Bettman

Charles Xiaoyi Wang

Edward C Rea, Jr

Robert W Johnson

Michael Yessik

A method for operating an extracavity frequency-converted solid-state laser for performing a laser processing operation is disclosed. The laser has a laser-resonator including an optically-pumped gain-medium. The resonator is configured to compensate for a predetermined range of thermal lensing in the gain-medium. An optically-nonlinear crystal located outside the resonator converts fundamental laser radiation delivered by the resonator into frequency converted radiation. The laser processing operation is performed by a train of pulses of the frequency-converted radiation having sufficient power to perform the processing operation. The power of frequency-converted radiation is dependent on delivery parameters of the laser radiation from the laser-resonator. The laser is operated in a manner which provides that the resonator delivers effectively the same average power of fundamental laser radiation before and during the laser processing operation. This provides that thermal-lensing in the gain-medium is within the predetermined range before and during a laser processing operation. Delivery parameters of the laser radiation before and during the processing operation are varied such that power of frequency-converted radiation generated before the processing operating is insufficient to perform a laser processing operation.

Laser rod thermalization

A diode laser device and method of use for achieving transcutaneous laser photocoagulation of the retina is described. A diode laser is used since it is much more efficient than the ion or dye lasers presently used for laser photocoagulation, and therefore will not require forced air of water cooling and can be made for compact. In addition, the diode laser can be used with standard 110 v wall sockets, and does not require the high power, three phase sockets required for the ion lasers. The end result is that compared to the ion laser device, the diode laser device can be brought directly into the operating room, which makes it ideal for transcutaneous delivery. A characteristic of diode lasers is that the emitted light diverges rapidly. In addition, the diode laser beam is emitted from a rectangular edge of a diode, and the light emitted along the longer sides of the rectangular edge will diverge more rapidly than that light emitted along the shorter sides of the rectangular edge. As a result, the emitted beam will become shaped as an ellipse as it travels from the rectangular edge. In one embodiment of the invention, the elliptical laser beam is shaped into a circle by an optical system before it is coupled to the fiber optic cable of the delivery system. In another embodiment, the fiber optic cable is directly coupled to the rectangular edge of the diode, making the optical system for shaping unnecessary.

Diode laser device for photocoagulation of the retina

Growing community of inventors

Cupertino, CA, United States of America

Acle V Hicks