The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 28, 2003
Filed:
Jul. 13, 2001
John J. Zayhowski, Pepperell, MA (US);
The United States of America as represented by the Secretary of the Air Force, Washington, DC (US);
Abstract
Many longitudinally pumped miniature lasers (single-frequency Nd:YAG microchip lasers and Q-switched microchip lasers) are sufficiently short that only a small fraction of the incident pump light is absorbed as it passes through the gain medium. The efficiency of such a laser is improved when the output face of the laser is coated to reflect the pump light, thereby allowing double-pass absorption of the light within the gain medium. The total absorption may still be small, however. Additionally, the divergence of typical pump sources (diode lasers or optical fibers) is large enough that there is often poor overlap between the reflected pump light and the oscillating mode, and the efficiency of the device is not significantly enhanced. If the output face of the miniature laser is coated to be highly transmitting to the pump radiation, the transmitted pump light can be collected with a lens and focused in to an amplifying medium (Nd:YVO ). The focusing optics will also focus the output of the laser, which may be concentric with the pump radiation, and good overlap between the collected pump light and the laser output can be obtained within the amplifier. If the amplifying medium is highly absorbing to the pump light and has high gain at the lasing wavelength, significant amplification can be obtained. The result is a simple, efficient, miniature laser/amplifier system pumped by a single pump source.