LLNL researchers have developed a TDLAS-based, standalone, real-time gas analyzer in a small form-factor for continuous or single-point monitoring. The system can analyze multiple gases with ultra-high sensitivity (ppm detection levels) in harsh conditions when utilizing wavelength-modulation spectroscopy (WMS).
Keywords
- Show all (218)
- Additive Manufacturing (44)
- Instrumentation (39)
- Synthesis and Processing (19)
- Diagnostics (12)
- Imaging Systems (9)
- Photoconductive Semiconductor Switches (PCSS) (9)
- 3D Printing (7)
- Electric Grid (7)
- Materials for Energy Products (7)
- Carbon Utilization (6)
- Semiconductors (6)
- Substrate Engraved Meta-Surface (SEMS) (6)
- Compact Space Telescopes (5)
- Data Science (5)
- Therapeutics (5)
- Laser Materials Processing (4)
- Material Design (4)
- Precision Optical Finishing (4)
- (-) Sensors (16)
- (-) Diode Lasers (4)
This invention proposes to engineer the current density along the length of a laser diode to overcome the penalty associated with non-uniformity resulting from asymmetry in the gain, photon or carrier density despite having uniform contact. Optimizing the current density profile enables diode lasers to operate with greater power conversion efficiency or operate with equivalent power conversion…
This invention proposes to engineer the temperature dependence of the emission wavelength of LEDs and laser diodes. The approach is to use a strain-inducing coating to counteract the intrinsic temperature coefficient of the emission wavelength of the LED or laser diode device thereby rendering it athermal. This invention avoids additional complexity, size, weight and power dissipation of…
This invention proposes a method to overcome the key limitation of electrically pumped lasers based on AlN, AlGaN, or AlInGaN, namely the lack of suitable shallow donor and acceptor dopants. As the band gap of these materials increases (and the emission wavelength decreases), both electrons and holes require greater thermal energies in order to ionize.
Laser diode lensing effect can be substantially reduced by creating a pattern interface such that the substrate is only attached at the diode mesa. This is achieved by either creating a pattern solder joint and/or pattern substrate.
This novel detector for characterizing IFE implosions is an alternative to the current RTNADs to measure neutron fluxes > 3x1011 neutrons/cm2 at high shot rates. The detector consists of a stack of small square metal wafers separated by thin insulating spacers. Every other wafer is held at high voltage while the remaining wafers are grounded. The stack acts as an…
LLNL’s SAS technology embedded within a facility is developed to sense, detect, localize, alert, and communicate an active shooter(s) to first responders. It relies on three integrated compact sensors that detect sound, infrared light (from the muzzle blast) and vibrations emanating from a gunshot. Fusing the data from these detectors minimizes false alarms.
The key to time-reversal for an active shooter detection/tracking application is being able to estimate the space-time transfer function (Green’s function) between source-enclosure-receiver. This approach begins with the acoustic mapping of an indoor muzzle blast.
LLNL researchers have designed and tested performance characteristics for a multichannel pyrometer that works in the NIR from 1200 to 2000 nm. A single datapoint without averaging can be acquired in 14 microseconds (sampling rate of 70,000/s). In conjunction with a diamond anvil cell, the system still works down to about 830K.
The LLNL method for optimizing as built optical designs uses insights from perturbed optical system theory and reformulates perturbation of optical performance in terms of double Zernikes, which can be calculated analytically rather than by tracing thousands of rays. A new theory of compensation is enabled by the use of double Zernikes which allows the performance degradation of a perturbed…
Transparent ceramic fabrication allows the production of gadolinium- , lutetium-, and terbium-based garnets which are difficult to grow by melt techniques due to phase instabilities. Phase stabilization of the garnets is accomplished by the addition of the intersubstitutional ions, Gallium and/or Scandium.
Scientists have developed many versatile and scaleable fabrication methods.…
LLNL's high fidelity hydrocode is capable of predicting blast loads and directly coupling those loads to structures to predict a mechanical response. By combining this code and our expertise in modeling blast-structure interaction and damage, along with our access to experimental data and testing facilities, we can contribute to the design of protective equipment that can better mitigate the…
LLNL researchers have grown and characterized scintillator crystals of Strontium Iodide (SrI2). Scintillator energy resolution and light yield proportionality surpass NaI and are similar to LaBr3. The SrI2 scintillators doped with europium (Eu) exhibit very high light yields (> 100,000 photons/MeV), extremely good energy resolution (<3% at 662 keV) and excellent light yield…
The LLNL detector measures radiation over a large dynamic range, spanning both high hazardous levels and weak levels, including natural background radiation. In weak radiation fields, the detector also measures gamma-ray spectra. The cost of the detector is significantly less than the total cost of existing separate detectors that could perform the same measurements.
LLNL's X-ray spectrometers based on STJ have been developed for high-resolution soft X-ray spectroscopy. STJ consist of two superconducting thin film electrodes separated by a thin insulating tunnel barrier. They measure X-ray energies from the increase in tunneling current after X-ray absorption in one of the electrodes excites additional charge carriers above the superconducting energy gap.…
LLNL has developed a radiation detector that cools to operating temperatures in 1-2 hours using two separate cooling stages. The first cooling brings the instrument to operating temperature. The embedded second cooling system achieves portable detection that can be sustained for 8-12 hours.
In addition, an integrated, hermetically-sealed package has been developed complete with…
LLNL has identified solution-grown organic crystals having scintillation efficiency not only close to, but even exceeding that of stilbene.. LLNL's invention relates to a new class of neutron detectors based on scintillation response of organic single crystals. More specifically, the use of organic molecules grown from solution and to molecules including the basic benzene or phenyl structure…
LLNL scientists have developed an approach for full spectrum analysis during gamma ray spectrometry using a spectral library signature created from a large amount of spectral data. The signature can be compared to unknown spectral measurements for the identification of previously unknown nuclear material.
Scientists at Lawrence Livermore National Laboratory have developed a plastic that can detect neutrons, something previously thought impossible.
Livermore scientists demonstrated a plastic scintillator that can discriminate between neutrons and gamma rays with a polyvinyltoluene (PVT) polymer matrix loaded with a scintillating dye, 2,5-diphenyloxazole (PPO). They have found that…
The invention utilizes the statistical nature of radiation transport as well as modern processing techniques to implement a physics-based, sequential statistical processor. By this we mean that instead of accumulating a pulse-height spectrum as is done in many other systems, each photon is processed individually upon arrival and then discarded. As each photon arrives, a decision is…
LLNL's neutron "Pillar Detector" fabrication technology uses semiconductor-based micro-structured elements as an electrical signal generation medium for the detection of neutrons. These materials in the form of semiconductor "pillars" embedded in matrix of high cross-section neutron converter materials (such as Boron) that emit charged particles upon interaction with neutrons. These charged…