Coherent light generators – Particular active media – Semiconductor
Reexamination Certificate
1998-12-04
2001-05-08
Font, Frank G. (Department: 2877)
Coherent light generators
Particular active media
Semiconductor
C372S018000, C372S092000, C372S098000, C372S099000
Reexamination Certificate
active
06229835
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a compact solid-state laser, and particularly to a compact solid-state laser used for a multiwavelength optical source for a wavelength-division-multiplexed communication system, a wide-spectrum optical source for spectroscopy, a ultra-short pulse source for distance measurement, a ultra-short pulse source for instrumentation, and the like. The invention also relates to a transmitter using this compact solid-state laser.
Various cavity structures for the solid-state laser have been proposed, as described for example in publication “Ultra Short Pulse Technology” (“KOGAKU” Japanese Journal of Optics, Vol.24, No.7, pp.378). Their basic structure includes four or more mirrors which form a cavity, a gain crystal as gain medium, and a prism pair or a grating pair which compensates the dispersion attributable to the gain crystal.
However, this basic structure has too many component parts and needs to space the prism pair or grating pair by several tens centimeters for dispersion compensation. Therefore, this structure it does not allow for the compact design of a solid-state laser. In the case of pulsative operation, the repetition frequency cannot be raised unless the cavity length is made short. The conventional solid-state laser has a repetition frequency of around 100 MHz, whereas the solid-state laser used for the communication system must have a repetition frequency of several gigahertz or higher.
There is a proposal for making the solid-state laser compact so that its repetition frequency is higher, as described in the article entitled “Compact Kerr-lens model-locked resonator” by B. E. Bouuma et al. in OPTICS LETTERS, Vol.21, No.2, pp.134-136, published in 1996. The proposed compact Kerr-lens model-locked resonator has its cavity made up of three elements including a gain crystal, a curved mirror, and a prismatic output coupler.
SUMMARY OF THE INVENTION
It is an object of the present invention to make the solid-state laser compact so that its repetition frequency is several gigahertz or higher and it is usable for the communication system.
For making a compact solid-state laser, it is necessary to reduce the number of component parts and compensate the dispersion attributable to the gain crystal without using the prism pair or grating pair. The above-mentioned proposal by B. E. Bouuma et al. uses a prism and a crystal pair, instead of using a prism pair, for dispersion compensation, thereby reducing the number of cavity elements to three so as to provide a compact solid-state laser.
In contrast, the present invention is intended to offer a compact solid-state laser which is designed to compensate the dispersion by means of a chirped mirror formed by multilayer coating (described in the article entitled “Chirped multilayer coating for broadband dispersion control in femtsecond laser” by Robert Szipocs et al. in OPTICS LETTERS, Vol.19, No.3, pp.201-203, published in 1994), so that the cavity is virtually formed of only two elements of a chirped mirror and a gain crystal. Specifically, the gain crystal has its one side rendered with a reflection coating, chirped-mirror coating, or saturable-absorber mirror coating so that it functions as a mirror, with the chirped mirror serving as another mirror of the cavity, thereby reducing the number of mirrors required.
REFERENCES:
patent: Re. 34192 (1993-03-01), Baer
patent: 5136596 (1992-08-01), Rao et al.
patent: 5249193 (1993-09-01), Watanabe
patent: 5856996 (1999-01-01), Durkin et al.
patent: 5986234 (1999-11-01), Mathews et al.
patent: 851205 A2 (1998-01-01), None
patent: 4-025084 (1992-01-01), None
Optics Letters, vol. 21, No. 2, Jan. 15, 1996, “Compact Kerr-lens model-locked resonator”, B.E. Bouuma et al, pp. 134-136.*
Optics Letters, vol. 19, No. 3, Feb. 1, 1994, “Chirped multilayer coating for broadband dispersion control in femtsecond laser”, R. Szipocs et al, pp. 201-203.*
Optics Letters, vol. 19, No. 14, Jul. 15, 1994, “Self-starting Kerr-lens mode locking of a Ti:sapphier laser”, G. Cerullo et al, pp. 1040-1042.*
Japanese Journal of Applied Physics, vol. 35, 1996, “All-Solid-State Mirror-Dispersion-Controlled Sub-10 fs Ti:Sapphier Laser”, K. Yamanak et al, pp. L989-L991.*
Kogaku, vol. 24, No. 7, (1995, 7), “Ultra Short Pulse Technology”, S. Watanabe, pp. 378(8)-383(13).*
“Center Mount”, Models 9807, 9813M and 9855 manufactured by v-Focus (Corp.).*
Ultima Series, manufactured by Newport (Corp.).
B.E. Bouma et al., “Compact Kerr-lens Mode-Locked Resonators”, OPTICS.*
Letters, vol. 21, No. 2, Jan. 15, 1996, pp. 134-136.*
T. Sorokina et al., “Femtosecond Pulse Generation From the Novel Low-Loss Chirped-Mirror Dispersion Controlled Cr: LiSAF and Cr:LiSGaF Lasers”, OSA Trends in Optics and Photonics Series, vol. 10 - Advanced Solid State Laser, Jan. 1997, pp. 322-325.
Petek Hrvoje
Tomaru Tatsuya
Font Frank G.
Hitachi , Ltd.
Mattingly, Stanger & Malur
Rodriguez Armando
LandOfFree
Compact solid-state laser and transmitter using the same does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Compact solid-state laser and transmitter using the same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Compact solid-state laser and transmitter using the same will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2532126