White Papers and Application Notes
X-Ray Toroids
Using toroidally shaped crystals is more practical now than ever, thanks to the high quality of synthetic crystals and state-of-the-art optical manufacturing and testing methods. For years, curved x-ray crystal optics have been used to analyze x-ray emissions in applications like analytical chemistry micro-probes and plasma diagnostics.
Production of Stilbene for Fast Neutron Detections
The organic scintillator stilbene is well-known as an excellent material for detection of fast neutrons in a gamma-ray background. Unfortunately, applications have been limited due to availability. Commercial production of stilbene using melt crystal growth techniques has not yielded material in large quantities and sizes. Solution crystal growth of stilbene has recently been demonstrated by researchers at Lawrence Livermore National Laboratory (LLNL) as a cost-effective alternative with the potential for scaling to large, high quality crystals. Inrad Optics is pursuing stilbene solution growth and fabrication in collaboration with LLNL to transfer that research to a production process.
Beryllium optics and beryllium-aluminum structures for reconnaissance applications
BAE Systems Inc., 450 Pulaski Road, Greenlawn, New York 11740
BAE Systems has developed and fielded the F-9120, a compact, lightweight, dual-band Electro-Optical/Infrared (EO/IR) long range sensor for high altitude tactical reconnaissance applications. The sensor’s weight and size allow it to be carried internally or in a pod on a variety of military aircraft. The challenge of maintaining optical performance over severe vibration and thermal environments has been met using beryllium optics coupled to a beryllium-aluminum structure. Material choices were vital to maintaining both the optical performance of the system over the environments as well as jitter control of the two-axis, inertially-stabilized gimbal. The beryllium and beryllium-aluminum combination has demonstrated unprecedented vibration performance in both laboratory and field environments. In addition, the close coefficient of thermal expansion (CTE) match between the optics and structure has enabled the sensor to meet its stringent imaging requirements over a wide temperature range as predicted.
Electro-Optic Behavior
Electrical Configurations. The configuration of the Pockels cell can be such that the electrical field is applied either longitudinally along the propagation direction of the light beam or transversely to it. Because of crystal symmetry and the desire for the light beam to experience no birefringence in the absence of an electric field, most KD*P Pockels cells are longitudinal-field devices all LiNbO3 and BBO Pockels cells are transverse-field devices.
Pockels cells can be configured to appear either as a capacitive load or as a portion of a coaxial transmission cable. Most INRAD Pockels cells are configured as capacitive loads with a typical capacitance of about 10 pF; the exact specifications can be found below. However, an impedance-matched design, the PKCM02, offers the advantage of being able to transmit a high voltage pulse or pulse sequence down a piece of transmission cable and have the voltage faithfully applied to the electrodes of the Pockels cell with subnanosecond rise and fall times.
Zinc Germanium Phosphide (ZGP)
Zinc Germanium Phosphide (ZGP) is one of those few reliable, efficient, high quality non-linear crystals that is beginning to dominate applications in a particular spectral region due to the unique properties of the material. A high non-linear coefficient (75 pm/V), good thermal conductivity (35 W/mK), relatively high Laser Damage Threshold (2-5 J/cm2 typically), and transparency with phase-matchability over the 2 μm – 8 μm range (and beyond) highlight the desirable properties of the material.
Soft X-ray Monochromators
Soft x-rays span the region between x-ray and UV and include energies from approximately 10 to 100 Å (0.12–1.2 keV)—a range that is particularly interesting for x-ray spectroscopy. While important applications include x-ray astronomy and metrology of high-energy plasmas, soft x-rays also have a potential use in next-generation surface inspection and material characterization tools. In these applications, the critical optical element is a high-quality crystal with suitable interplanar spacing to permit diffraction and focusing of soft x-rays. Inrad Optics offers several crystals that are suitable for these applications.
Custom Crystals for Doubling Ultrafast Ti:Sapphire Pulses
In the years since their first demonstration at MIT Lincoln Labs in 1982, mode-locked Ti:Sapphire oscillators have become almost ubiquitous. The ultrashort, tunable output pulses from these lasers permit investigation of previously extremely difficult to study phenomena. Typical output from these lasers ranges from red to near infrared, yet for many applications which require high peak powers and ultrashort pulses, shorter wavelengths are desirable. Harmonic generation using nonlinear optical crystals has become one of the most popular methods of reaching these wavelengths.