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Santa Monica, CA, United States

Patel C.K.N.,Pranalytica
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2012

QCLs are becoming the most important sources of laser radiation in the midwave infrared (MWIR) and longwave infrared (LWIR) regions because of their size, weight, power and reliability advantages over other laser sources in the same spectral regions. The availability of multiwatt RT operation QCLs from 3.5 μm to >16 μm with wall plug efficiency of 10% or higher is hastening the replacement of traditional sources such as OPOs and OPSELs in many applications. QCLs can replace CO 2 lasers in many low power applications. Of the two leading groups in improvements in QCL performance, Pranalytica is the commercial organization that has been supplying the highest performance QCLs to various customers for over four year. Using a new QCL design concept, the non-resonant extraction [1], we have achieved CW/RT power of >4.7 W and WPE of >17% in the 4.4 μm - 5.0 μm region. In the LWIR region, we have recently demonstrated QCLs with CW/RT power exceeding 1 W with WPE of nearly 10 % in the 7.0 μm-10.0 μm region. In general, the high power CW/RT operation requires use of TECs to maintain QCLs at appropriate operating temperatures. However, TECs consume additional electrical power, which is not desirable for handheld, battery-operated applications, where system power conversion efficiency is more important than just the QCL chip level power conversion efficiency. In high duty cycle pulsed (quasi-CW) mode, the QCLs can be operated without TECs and have produced nearly the same average power as that available in CW mode with TECs. Multiwatt average powers are obtained even in ambient T>70°C, with true efficiency of electrical power-to-optical power conversion being above 10%. Because of the availability of QCLs with multiwatt power outputs and wavelength range covering a spectral region from ∼3.5 μm to >16 μm, the QCLs have found instantaneous acceptance for insertion into multitude of defense and homeland security applications, including laser sources for infrared countermeasures for protecting aircraft from MANPADS, testing of infrared countermeasures, MWIR and LWIR lasers for identify-friend-or-foe (IFF) personnel beacons, infrared target illuminators and designators and tunable QCL applications including in-situ and standoff detection of chemical warfare agents (CWAs) and explosives. The last of these applications addresses a very important and timely need for detection of improvised explosive devices (IEDs) in combat environments like Iraq and Afghanistan. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase I | Award Amount: 149.40K | Year: 2014

We propose the development of an ultra-compact and highly reliable quantum cascade laser (QCL) two-color module with operating range from 100m to over 3km for weapon-mounted applications and up to 10km for small unmanned aircraft systems. Operational characteristics of QCLs in the module will be carefully tailored to provide the required optical power intensity on the target at the highest wall plug efficiency to ensure the longest run time from batteries. Electronic control of each laser will enable the user to operate the system with one or any combination of QCLs, thus optimizing the run-time with CONOPS. Output optical beam will be circularized on laser chip level to reduce the cost of the beam expander optics. The module will measure less than 3"x 1"x 2"with continuous run times of up to 30 minutes and intermittent 30 second on 1 minute off cycles for up to 4 hours. The manufacturing analysis shows that that fabrication cost of the laser module of $5,000 for the batch size of at least 1,000 units is realistic.

A system for collecting gas samples emitted from skin and detecting concentrations of specified components therein. The system includes a collection chamber housing defining an interior space, the collection chamber housing having a gas inlet, a gas outlet, and an opening. The opening is configured for enclosing a skin portion from which to receive an emitted gas sample and sealing the interior space against the skin portion. An inert gas source is connected to the gas inlet, which is capable of allowing inert gas from the inert gas source to flow into the interior space. A gas cell is connected to the gas outlet, which is capable of allowing the inert gas and the gas sample to flow from the interior space into the gas cell. As a laser travels through the gas cell, power and optoacoustic signals are measured and used to determine a concentration of the specified component.

Agency: Department of Defense | Branch: Navy | Program: SBIR | Phase: Phase I | Award Amount: 79.47K | Year: 2014

Development of a 100W QCL platform based on 2-D QCL bar array is proposed. QCL bar geometry will be optimized for the highest wall plug efficiency under full operating conditions. Each element in the array will deliver optical power of 3W to 4W in high quality beam with beam quality parameter M2 = 1.5. The QCL platform will be designed so that each element in the array could be individually controlled. The platform output optical power will be scalable up to 1kW. Waste heat generated by the QCL bars will be removed by a two phase cooling system. Compared with traditional single-phase microchannel coolers, the two-phase cooling takes advantage of the latent heat of vaporization of the refrigerant, which enables the evaporator to handle higher fluxes with significantly lower mass flowrates, i.e., less pumping power resulting in a more compact system. The cooling system will be insensitive to orientation and will be designed to operate under several g"s of shock/acceleration. Unprecedented combination of the high optical power and small size of the entire platform will pave the way to a new generation DIRCM systems to counter emerging new generation of MANPADS and other DoD applications.

Agency: Department of Defense | Branch: Army | Program: STTR | Phase: Phase I | Award Amount: 149.66K | Year: 2014

In response to the Army STTR Topic A14A-T015 solicitation for tunable high-power LWIR lasers for standoff detection applications, Pranalytica proposes to develop a compact, rugged and highly reliable wavelength tunable quantum cascade laser (QCL) module delivering over 5W of peak power and over 0.5W of average power in the spectral region spanning from 7 to 11µm. The proposed approach is based on a new external cavity configuration, not used for QCLs heretofore, and offers several critical advantages, over either the QCL arrays or the traditional grating external cavity QCL, for practical field applications, including rapid wavelength tuning, high manufacturing yield, and compatibility with standard QCL packaging. Unprecedented combination of the projected operational characteristics of the module will pave the way to a new generation of standoff detection systems.

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