Component Blog Posts

How Can We Help Your Gas Sensing and Other Applications Succeed?

Single-frequency lasers have long been the cornerstone of standoff gas detection applications, particularly in traditional LIDAR (Light Detection And Ranging), DIAL (Differential Absorption LIDAR), and TDLAS (Tunable Diode Laser Absorption Spectroscopy).  More recently, as single-frequency laser diodes have become more common and less expensive, they are being utilized in more localized and industrial gas sensing applications.

A large number of the molecules of interest for gas sensing have strong absorption in the near infrared region, for example; NH2 at 1512 nm, H2O at 1392 nm & 1877 nm, CH4 at 1654 nm, and CO2 at 2004 nm.   As a result, our propitiatory Discrete Mode (DM) single-frequency laser diode technology is an ideal solution for this application, available in wavelengths from 1270nm up to 2300nm.

Eblana Gas Wavelengths.png

These REP Series lasers, featuring Discreet-Mode (DM) technology (a DFB-like technology), allow for excellent side mode suppression ratio (SMSR – up to 40dB) and narrow linewidth (<2MHz), which make them an effective solution for Gas Sensing and scientific needs. Since laser-based gas sensing requires excellent tuning characteristics, our DM lasers are the ideal choice as they feature mode-hop-free tuning over a minimum of 2nm.

In our DM laser diodes, single-frequency operation is achieved by introducing index perturbations etched into a few specific locations along the wave-guide. This manipulates the Fabry-Pérot cavity loss, resulting in the enhancement of one longitudinal mode and the suppression of all others, as can be seen in the figure below. This results in a single-mode output spectrum with >40dB SMSR. To ensure similar performance from a DFB laser with a stable single-frequency operation requires asymmetric or low reflectivity coated laser facets, which can induce either modal instability or linewidth broadening.

Eblana SMSR Graph

At RPMC Lasers we currently offer these single-frequency REP Series lasers in a wide variety of packages depending on the application, operating environment, and integration requirements. Our technology platform gives you the freedom to specify your laser characteristics from the widest possible range of electro-optical parameters. With wavelengths spanning 1270nm to 2300nm, coupled with package options ranging from simple TO-Can to a PM fiber pig-tailed butterfly package, we can deliver a laser to completely meet your requirements in the shortest time frame and at a competitive cost to fit your budget. Whether you require a minor modification to an existing standard product or wish to specify a custom laser product from the ground up, our team of laser physicists and engineers are on hand to assist you from start to finish to ensure that you get the support you need, as well as a laser that completely satisfies the needs of your custom application.

   See Our Discreet Mode Diode Lasers   

Package Options:

The preferred package depends on the application, operating environment, and integration needed.  We offer various packages suited to meet your needs.

14-pin butterfly



Our 14-pin butterfly is designed with stability and ease of use in mind. Tested to Telcordia standards, it is the ideal package for thermal stability and fiber coupled integration.

Key features

– Temperature controlled
– PM/SMF coupled with FC/APC
– Built-in optical isolator

TO-39 with TEC


We have worked with industrial partners in order to design a free space package specifically for the gas sensing industry. The TO-39 incorporates an internal TEC for accurate wavelength control.

Key features

– Temperature controlled
– Angled AR coated window
– Free-space design



Typically used for high volume communications applications, our TO-56 package is tested to Telcordia standard and is RoHS qualified. Available with flat window or with a ball lens.

Key features

– Free-space design
– Hermetically sealed
– Flat window or 1.5 mm ball lens

High speed

7-pin butterfly

R1Z1_EP_7-pin Butterfly_Package


The high speed and pulsing capabilities of our DM and FP laser diodes can be fully exploited using the high speed 7-pin butterfly, which incorporates a K-connector for modulation up to 10 GHz.

Key features

– K-connector for high speed modulation
– PM/SMF coupled with FC/APC
– Built-in optical isolator

DX-1 Module



Our proprietary DX-1 incorporates the butterfly module with an integrated current driver and TEC controller. Designed for ease of operation, it is the ideal platform for high stability gas detection or remote sensing.

Key features

– Integrated driver and TEC controller
– PM/SMF coupled with FC/APC
– Built-in optical isolator
– Powered by +5 V DC source

These single-frequency laser diodes are ideal for gas sensing and other scientific applications.  The REP series of DM laser diodes possess inherently narrow linewidth relative to traditional DFBs, in addition to superior electro-optical performance with respect to output power, threshold, SMSR (up to 40dB) and tuning characteristics. These devices are available as OEM components (14-pin BF packages and TO-cans), as well as modules complete with drive electronics and TEC control. All of these single-mode lasers are of monolithic construction making them ideal for operation in environments prone to mechanical shock and vibration. We have supplied lasers to a range of aerospace applications including the European Space Agency’s next generation atomic clock development program. If you would like to learn more about these Discreet Mode Laser Diodes, please contact us with the button below, or call us at 636.272.7227!