Laser diode array with an in-phase output

Details Laser diode array with an in-phase output Laser diode array with an in-phase output

2002-10-03

2003-12-23

Ip, Paul (Department: 2828)

Coherent light generators

Particular active media

Semiconductor

C372S046012, C372S045013

Reexamination Certificate

active

06668003

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The subject matter disclosed generally relates to the field of semiconductor lasers.
2. Background Information
Semiconductor lasers are used in a variety of system applications. For example, semiconductor lasers are used as a light source in fiber optic communication systems. It is generally desirable to provide a semiconductor laser that has a high power output. High power output reduces the number of repeaters and amplifiers required for the optical system.
FIG. 1
shows a laser diode array
1
that contains a plurality of laser stripes
2
each separated by an unpumped region
3
. Each laser stripe
2
emits a laser beam. Collectively, the laser stripes
2
increase the power output of the device
1
.
The laser stripes
2
are formed in relative close proximity to each other. Consequently, there is a coupling between stripes
2
due to the electromagnetic fields emitted by the laser beams formed therein. This coupling creates various operating modes.
As shown in
FIG. 2
the stripes may be coupled in a coherent “supermode” where adjacent stripes operate in-phase. The in-phase supermode creates a high power, high quality diffraction limited output beam.
Unfortunately, most laser diode arrays operate in an anti-phase supermode where adjacent stripes are 180 degrees out of phase from each other. The anti-phase supermode is shown in FIG.
3
. In the anti-phase supermode, the intensity profile more closely matches the amplification gain profile of the array, where both gain and light intensity are at a minimum in the unpumped regions that separate the stripes. This matching of intensity and gain tends to induce the array to operate in the anti-phase supermode.
The resultant output beam of a laser diode array operating in the anti-phase supermode has a double peak rabbit ear shape with minimums at 0 degrees. Such a waveform is difficult to focus and is essentially useless for applications that require a high quality, diffraction limited beam.
BRIEF SUMMARY OF THE INVENTION
A laser diode array that includes two or more laser stripes. The laser diode array also includes a phase shifter appended to every second laser stripe.


REFERENCES:
patent: 4751707 (1988-06-01), Krebs et al.
patent: 4757268 (1988-07-01), Abrams et al.
patent: 4791648 (1988-12-01), Vojak et al.
patent: 5953359 (1999-09-01), Yamaguchi et al.
patent: 6025060 (2000-02-01), Meissner
patent: 6289032 (2001-09-01), Fay et al.
patent: 6480513 (2002-11-01), Kapany et al.
patent: 2002/0009274 (2002-01-01), Gharavi

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