SBIR-STTR Award

Vibration Impact and Pressure (VIP) Sensors Inc. proposes to develop a small, very low noise, highly sensitive low power, extrinsic fiber-optic sensor and signal processing module that can be integrated into a single node of the Autonomous Undersea Weapon System (AUWS) for target detection, classification, localization and tracking (DCLT). This sensor is enclosed in a cylindrical canister containing a battery pack, a miniature Optical MOMS(micro-optical-mechanical-systems) sensor chip, and a surface mounted printed circuit board that includes all the electronics to process the sensor signals through highly effective DCLT algorithms, and when appropriate, broadcasts commands to other deployed assets. Normally different nodes with different types of sensors would be needed to provide proper AUWS trigger information. VIP Sensors proposes for this program to specifically develop a single sensor, a fiber optic hydrophone, specially designed to be a multi-mode distributed sensor. Multiple fiber-optic sensors of different types (accelerometer, magnetometer, pressure, etc.) can be processed with the same hardware and be included in the same sensor module. The fiber-optic sensors are miniature MOMS Silicon chips based on the Extrinsic Fabry-Perot Interferometric principle. The MOMS technology allows customizing the performance and design for different types of sensor modalities and low cost production rates.

Keywords:
Fiber Optic Sensors, Fiber Optic Sensors, Multi-Drop Sensor Arrays, Magnetometer, Accelerometer, Hydrophone, Optical Mems, Optical Detection

The successful results of the Phase I work will be utilized by implementing an optimized ultra-short pulse Optical Parametric Chirped Pulse Amplifier at an eye safer Short Wave InfraRed (SWIR) wavelength. The system will be designed with a goal of 1 kHz repetition rate and will ultimately reach a pulse energy of 100 mJ in two OPA stages. The OPA process was chosen due to its inherent 100% efficiency, i.e., all input laser energy is either instantaneously transferred to the signal and idler beams or stays in the pump. A number of novel techniques demonstrated in Phase I will increase the energy transfer into the signal and idler beams to over 90%. These same techniques will reduce the small absorption of the idler beam in the OPA crystals to less than 1 Watt each at the full 100 Watt average output power. Combined with efficiency improvements in other aspects of the laser system these techniques will reduce the required pump energy by 75%. The use of pulsed DPSS technology and other novel techniques in the pump laser will reduce the thermal load on the gain modules to a sufficiently small level to allow for 1 kHz operation.

Benefit:
Ultra-Short Pulse Lasers (USPL) are utilized to create localized sources of ultra-broadband EM / photonic radiation. The high average power USPL sources developed in this work will improve signal to noise ratio in femtosecond spectroscopy and related remote sensing applications; increase speed of repetition rate-intensive applications such as machining and surgery; and aide military and similar applications by reducing dwell time per unit area. The eye safer SWIR wavelength of the proposed laser is ideal for military applications in a field environment due to its much higher MPE (Maximum Permissible Exposure). A side benefit of the proposed design is the generation of intense femtosecond pulses at both 800 nm and 3.4 microns, corresponding to the so-called idler 0x9D beam generated in the Optical Parametric Amplifier (OPA) process. This combination of wavelengths will provide options appropriate for counter ISR (Interrogation, Surveillance, and Reconnaissance) missions against a broad range of systems.

Keywords:
High power laser, optical parametric amplifier, directed energy, Ultra-short pulse laser, High Energy Laser, OPCPA, Laser amplifier, LASER