What is a DFB Laser?
86.8 هزار بار بازدید -
13 سال پیش
-
http://www.fiberoptics4sale.com/wordp...
Hello everyone! This is Colin from Fiber Optics For Sale.
In this tutorial, we will quickly explain what is a DFB laser. So let's get started.
What does DFB mean? Here, DFB means "Distributed Feedback".
In a DFB laser, on top of its active region, there is a diffraction grating. This diffraction grating functions as a Bragg reflector, basically a mirror. Now let's take a closer look.
This figure shows the cross section view of a DFB laser.
DFB lasers do not use two mirrors to form the optical cavity as used in conventional lasers such as a FP laser. Instead, a diffraction grating is formed on the upper waveguide layer on top of the active region. The active region is composed of multiple quantum wells, and then the active region is buried with current blocking layers.
Traditionally, DFB lasers have antireflection coated on one side of the cavity and high reflectivity on the other side. In this case the grating forms the distributed mirror on the antireflection coated side, while the high reflectivity side forms the other mirror.
The grating is constructed so as to reflect only a narrow band of wavelengths, and so produce a single lasing mode. This wavelength is determined by the grating's period. Conventional DFB lasers have a single mode wavelength from 1.3 to 1.55 µm.
This picture shows exactly how a DFB laser works. The Bragg grating works like a mirror, selectively reflecting only one wavelength. This wavelength can be found from the Bragg condition.
These pictures show the emission spectrum of a DFB laser at 1545 nm. The background radiation is suppressed by more than 50 dB.
DFB lasers come in many different packages. The first picture shows a coaxial pigtailed DFB Laser Diode. The second picture shows a 14 pin butterfly packaged DFB laser. The third picture shows a 5.6mm diameter TO-CAN packaged DFB laser.
So there you have it. Please leave your comment below if you'd like to see other topics.
Don't forget to visit fo4sale.com for more free fiber optic tutorials.
I hope you learned a thing or two from this tutorial. I will see you in the next video!
Hello everyone! This is Colin from Fiber Optics For Sale.
In this tutorial, we will quickly explain what is a DFB laser. So let's get started.
What does DFB mean? Here, DFB means "Distributed Feedback".
In a DFB laser, on top of its active region, there is a diffraction grating. This diffraction grating functions as a Bragg reflector, basically a mirror. Now let's take a closer look.
This figure shows the cross section view of a DFB laser.
DFB lasers do not use two mirrors to form the optical cavity as used in conventional lasers such as a FP laser. Instead, a diffraction grating is formed on the upper waveguide layer on top of the active region. The active region is composed of multiple quantum wells, and then the active region is buried with current blocking layers.
Traditionally, DFB lasers have antireflection coated on one side of the cavity and high reflectivity on the other side. In this case the grating forms the distributed mirror on the antireflection coated side, while the high reflectivity side forms the other mirror.
The grating is constructed so as to reflect only a narrow band of wavelengths, and so produce a single lasing mode. This wavelength is determined by the grating's period. Conventional DFB lasers have a single mode wavelength from 1.3 to 1.55 µm.
This picture shows exactly how a DFB laser works. The Bragg grating works like a mirror, selectively reflecting only one wavelength. This wavelength can be found from the Bragg condition.
These pictures show the emission spectrum of a DFB laser at 1545 nm. The background radiation is suppressed by more than 50 dB.
DFB lasers come in many different packages. The first picture shows a coaxial pigtailed DFB Laser Diode. The second picture shows a 14 pin butterfly packaged DFB laser. The third picture shows a 5.6mm diameter TO-CAN packaged DFB laser.
So there you have it. Please leave your comment below if you'd like to see other topics.
Don't forget to visit fo4sale.com for more free fiber optic tutorials.
I hope you learned a thing or two from this tutorial. I will see you in the next video!
13 سال پیش
در تاریخ 1390/07/20 منتشر شده
است.
86,839
بـار بازدید شده