The Defense Systems Information Analysis Center (DSIAC) received an inquiry requesting information on invisible lasers, light-emitting diodes (LEDs), or other technologies for target illuminators at technology readiness level (TRL) 6 or higher, preferably TRL 9. A DSIAC subject matter expert (SME) contacted a variety of original equipment manufacturers, government organizations, and contractors. Additionally, the SME searched the Defense Technical Information Center (DTIC) Research and Engineering (R&E) Gateway database, laser vendor websites collected from the Directed Energy Professional Society (DEPS), Photonics West Exhibitors, and well-known manufacturers in the field. The SME stated that there are many off-the-shelf fiber lasers that appear to satisfy the majority of the stated requirements. Typically, the most difficult requirement to achieve is the shock and vibration (mostly due to lack of information from the manufacturers), but the industrial nature of these lasers may make them suitable. Additionally, the power source for the lasers prove to be challenging as some require two- or three-phase power. Based on the SME’s research, the IPG Photonics YLR-1000 laser appeared to be the best fit to the requirements and has been previously ruggedized by Fibertek, Inc. for use in an airborne application.
1.0 Introduction
A Defense Systems Information Analysis Center (DSIAC) subject matter expert (SME) contacted several U.S. government agencies and industrial companies to request information on a target illuminator that met the inquirer’s specifications, including the following:
- Defense Advanced Research Projects Agency (DARPA).
- Directed Energy Joint Technology Office (DE-JTO).
- Directed Energy Professional Society (DEPS).
- Coherent, Inc.
- RPMC Lasers.
- Fibertek, Inc.
The SME also searched the Defense Technical Information Center (DTIC) Research and Engineering (R&E) Gateway database for information from original equipment manufacturers (OEMs), academia, the U.S. Department of Defense (DoD), and other government agencies. Additionally, the SME searched laser vendor websites collected from DEPS, Photonics West Exhibitors, and well-known manufacturers in the field. Pertinent findings were summarized and compiled in this report.
2.0 Summary of Findings
Table 1 summarizes the lasers identified by DSIAC that potentially meet the inquirer’s requirements. There are many commercial off-the-shelf (COTS) items that generally meet most of the requirements but may need to be modified for appropriate platform requirements. Most systems do not provide information regarding environmental ruggedness besides temperature and humidity as shock and vibration data are not present. Furthermore, many of the systems identified in Table 1 require alternating current (AC) power—at times, two-phase or three-phase—due to the large optical powers generated along with separate liquid cooling units (not included in SWaP). The DSIAC SME noted that due to the limited time given to complete this search and the lack of response from some of the contacted contractors, there are likely more ruggedized versions of industrial lasers available from companies such as Raytheon, Lockheed, and Northrop Grumman. However, the IPG YLR-1000 laser, identified in Table 1, appears to meet the inquirer’s system requirements and was previously ruggedized by Fibertek for use in an airborne application. Specifically, Fibertek, Inc. ruggedized the YLR-1000 for mounting in an Apache helicopter [1].
Table 1: Comparison of Potential Laser Systems [2–8]
| Manufacturer | Model number | Wavelength (nm) | Output power (watts) | Volume (mm × mm × mm) | Weight (kg) | Beam quality | Wall plug efficiency |
| IPG [2] | YLR-1000 YLR-1500 |
1070 | 1000 1500 |
448 × 680 × 177 | 70 | 1.1 | — |
| IPG [3] | ELS-2000 | 1567 | 2000 | 856 × 806 × 1206 | 350 | — | 18% |
| SPI Lasers [4] | redPower Prism 1 kW | 1075–1080 | 1000 | 2 U (88 mm) × 445 × 550 | — | 1.1 | ~30% |
| redPower Prism 1.5 kW | 1500 | 2 U (88 mm) × 445 × 702 | |||||
| redPower Prism 2 kW | 2000 | 2 U (88 mm) × 445 × 702 | |||||
| nLight [5] | CFL-1000 | 1070 | 1000 | 480 × 677 × 177 | — | 1.1 | — |
| CFL-1200 | 1200 | ||||||
| Lumentum [6] | YLE2100 | 1080 | 2100 | — | — | — | — |
| Coherent [7] | HighLight FL1000CSM | 1070 | 1000 | 751 × 953 × 584 | 150 | — | ~30% |
| HighLight FL1500CSM | 1500 | ||||||
| HighLight FL2000CSM | 2000 | ||||||
| HighLight FL2500CSM | 2500 | ||||||
| Laserline [8] | LDM Line | 900–1080 | 1000 | 480 × 220 × 636 | 50 | — | ~25% |
| 2500 | 480 × 220 × 636 | 50 | |||||
| 3500 | 480 × 220 × 636 | 50 | |||||
| 5000 | 480 × 220 × 705 | 110 | |||||
| 6000 | 480 × 220 × 705 | 110 | |||||
| Convergent Photonics [9] | CF1000 | 1070–1080 | 1000 | 501 × 89 × 787 | 23.5 | — | 32% |
2.1 Original Equipment Manufacturers (OEMs)
2.1.1 IPG Photonics
IPG Photonics is one of the most popular fiber laser companies for both DoD and industrial applications. While their ELS-2000 series of fiber lasers provides a source in the 1567-nm band, it requires three-phase power and has a high SWaP [3]. However, the YLR-1070 series is rack mounted, has relatively low SWaP, and was previously installed in aircraft [1, 2].
2.1.2 SPI Lasers
SPI Lasers of the United Kingdom sells industrial laser systems. Their redPOWER prism series of lasers is rack mounted, has relatively low SWaP, and runs off 48 volts of direct current (VDC) [4].
2.1.3 nLight
nLight is a semiconductor and fiber laser company that produces a single-mode, rack-mounted fiber laser that seems to fit most of the requirements for this application. However, it requires 200–240 volts of alternating current (VAC) and is not rugged [5].
2.1.4 Lumentum
Lumentum is an optical component company that primarily builds laser transmitter components. Their Corelight series of fiber lasers is rack mounted. The company’s datasheets provided limited information, but they are one of the few manufacturers that provided specifications for shock and vibration [6].
2.1.5 Coherent
Coherent is a large industrial and scientific laser manufacturer and has numerous products across both pulsed and continuous wave systems, from ultraviolet through infrared. The HighLight FL Single Mode Series of lasers best meets the inquirer’s requirements; however, these lasers require three-phase AC power and large cooling units, and their SWaP may limit their applications [7].
2.1.6 Laserline
Laserline is a German company that produces industrial lasers. Their LDM series has high power but has a large SWaP and requires three-phase power [8].
2.1.7 Q-Peak
No information on this type of laser was available on the Q-Peak website, although the DSIAC SME noted that they may have potentially built suitable lasers on government contracts.
2.1.8 Raytheon
Although it was not possible to contact Raytheon Electronic Systems within the timeframe of the request, it is known that they have previously built tracking illuminator lasers (TILLs) for the Airborne Laser Program (ABL).
2.1.9 Northrop Grumman
Although it was not possible to contact Northrop Grumman Space Systems within the timeframe of the request, the DSIAC SME noted that they have previously built beacon illuminator lasers (BILLs) previously for the ABL.
2.1.10 Furukawa Electric
It was not possible to contact Furukawa Electric, a Japanese electronics company, but the DSIAC SME noted that they do produce high-power industrial lasers.
2.1.11 Convergent Photonics
Convergent Photonics is an industrial laser manufacturer whose CF series of fiber lasers is the closest fit to the requirements. The system is rack mountable, has the lowest stated SWaP of any of the observed systems, and requires one-phase 90/230/264 VAC [9].
2.2 Fibertek, Inc.
Fibertek is a contract laser manufacturer, not an OEM. They expressed that they could create a custom laser with the specifications, but it most likely wouldn’t be necessary as IPG Photonics has a suitable laser. However, the IPG laser is potentially not as rugged as would be required. Fibertek has worked with a government customer to modify a COTS laser, so it met airworthiness requirements to be mounted in an Apache helicopter [1].
2.3 DARPA
DARPA’s Autonomous Real-Time Ground Ubiquitous Surveillance–Infrared (ARGUS-IR) aimed to provide persistent surveillance, high-resolution aerial infrared photographs with sufficient image resolution to distinguish dismounted soldiers. This system does not have any active illuminators [10].
2.4 DTIC Search
A DTIC search for “shortwave infrared,” “SWIR,” “illumination laser,” “track illumination laser,” “beacon illumination laser,” “CW,” “kW,” and “high power” did not result in any information on systems that fit the requirements.
References
[1] Fibertek Laser. Personal communication with an Engineer at Fibertek, 16 January 2019.
[2] IPG Photonics. “YLR-1070 Series.” https://www.ipgphotonics.com/en/173/ FileAttachment/ YLR-1070+Series+Datasheet.pdf, March 2018.
[3] IPG Photonics. “ELS-2000.” https://www.ipgphotonics.com/en/48/ FileAttachment/ELS-2000+Data+Sheet.pdf, January 2014.
[4] SPI Lasers. “SPI Lasers Datasheets.” https://www.spilasers.com/register-for-datasheets/, accessed January 2019.
[5] nLIGHT. “nLIGHT Single Mode Rackmount Fiber Lasers.” http://nlight.net/nlight-files/ file/datasheets/fiber-lasers/Datasheet-500-1500W-SM-180807.pdf, 2018.
[6] Lumentum. “CORELIGHTTM Series Fiber Laser Engines.” https://www.solidstatelasersource.com/files/pdfs/solidstatelasersource_com/product-372/Lumentum_Fiber_Laser_1080nm_6300W_CW-1470669656.pdf, 2015.
[7] Coherent. “HighLight FL Single Mode.” https://edge.coherent.com/assets/pdf/ COHR_HighLightFL_Compact_SingleMode_DS_0818.pdf, 2018.
[8] Laserline. “Laserline LDM: The Compact Class for Diode Laser.” https://docplayer.net/ 49552576-Laserline-ldm-the-compact-class-for-diode-laser.html, accessed January 2019.
[9] Convergent. “CF 1000 – High Power Industrial Fiber Lasers.” http://www.convergent-photonics.com/wp-content/uploads/2018/05/CF1000_rev.02.pdf, May 2018.
[10] DARPA. Personal communication with a Scientific, Engineering, and Technical Assistance (SETA) contractor, 15 January 2019.