Important Parameters When Selecting a DFB Butterfly Laser

Choosing a DFB butterfly laser requires more than checking its center wavelength or output power. Several parameters should be considered according to the actual application.

Main Parameter and Description

Center Wavelength:Determines the operating wavelength and must match the application

Optical Output Power:Indicates the available optical power

Spectral Linewidth:Describes the width of the emitted optical spectrum

Side-Mode Suppression Ratio (SMSR):Measures the suppression of the strongest side mode relative to the main mode

Threshold Current:The current required to reach the onset of laser oscillation

Operating Current:The drive current required to achieve a specified output power

Wavelength Temperature Coefficient:Indicates how much the wavelength changes with temperature

Fiber Type:Determines whether single-mode or polarization-maintaining fiber is required

TEC Operating Parameters:Help determine compatibility with the temperature control system

Optical Isolation:Indicates the isolator's ability to suppress backward-propagating light

Other considerations include package dimensions, pin configuration, fiber connector type, operating temperature range, and long-term reliability.

Although the 14-pin butterfly package is widely used, pin assignments are not necessarily identical across different products. Never assume the wiring configuration based only on the package appearance or pin count.