Mr. Paul Klocek Profile

Paul Klocek

CEO at Brain Foundry LLC

SPIE Involvement:

Publications (21)

PROCEEDINGS ARTICLE | July 26, 1999

Advances in low-cost long-wave infrared polymer windows

Proc. SPIE. 3705, Window and Dome Technologies and Materials VI

KEYWORDS: Long wavelength infrared, Infrared imaging, Refractive index, Antireflective coatings, Imaging systems, Polymers, Ultraviolet radiation, Resistance, Infrared radiation, Photorefractive polymers

Read Abstract

PROCEEDINGS ARTICLE | August 8, 1996

Infrared optical materials

Proc. SPIE. 10286, Inorganic Optical Materials: A Critical Review

KEYWORDS: Diamond, Magnesium fluoride, Glasses, Crystals, Germanium, Gallium arsenide, Zinc, Infrared radiation, Infrared materials, ZBLAN

Read Abstract

SPIE Conference Volume | August 8, 1996

Inorganic Optical Materials: A Critical Review

PROCEEDINGS ARTICLE | September 28, 1994

Thermo-optic, thermo-mechanical, and electromagnetic effects in IR windows and domes, and the rationale for GaAs, GaP, and diamond

Proc. SPIE. 2286, Window and Dome Technologies and Materials IV

KEYWORDS: Diamond, Sensors, Germanium, Gallium arsenide, Silicon, Resistance, Zinc, Domes, Wavefront distortions, Absorption

Read Abstract

Electro-optical (EO) systems, the platforms they perform on, and their missions continue to place increasing requirements on the infrared windows and domes associated with these systems. Supersonic flight, observability, EMI shielding, sensor range, multispectral sensors, environmental degradation resistance (sand and rain erosion resistance), and affordability are some of the requirements that are rendering most current IR window and dome technologies inadequate. Texas Instruments (TI), through both IR&D and DoD contract work, has been developing enabling IR materials technology to address these critical needs. Specifically, our work on CVD diamond, gallium arsenide (GaAs), gallium phosphide (GaP), and polymers is described and compared with othe IR window and dome materials. Trade studies involving thermal shock, transmission, absorption, emission, strength, durability, protective coatings, EMI shielding, transmitted wavefront distortion, and material status are presented. High-speed IR domes for use with 8- to 12 micrometers sensors on Mach 3 or greater missiles will generally require diamond; slower missiles could use ZnS, GaAs, and possibly GaP. For Mach 3 or greater missile systems with IR sensors operating in the 3- to 5-micrometers range, GaP is the most promising material, with its higher thermal shock resistance and lower absorption and, therefore, lower emission at elevated temperatures at 3 to 5 micrometers than sapphire, spinel, yttria, ALON, Si or ZnS. For multispectral use (3 to 5 and 8 to 12 micrometers ) at supersonic speeds, GaP and multispectral ZnS are the candidates; low supersonic use could include GaAs; and subsonic use could include ZnSe. For IR windows and domes where EMI shielding is required, GaAs offers the highest shielding of any window with or without metal grids. Si, Ge, and GaP offer bulk electrical conductivity like GaAs, but, because of the intrinsic behavior of the carriers, cannot offer the same level of shielding. Durability is a growing concern on all IR windows and domes. Various coatings for rain and sand erosion including diamond, BP, and TI GaP, amorphous carbon and novel Ti IR polymers are discussed.

SPIE Conference Volume | September 28, 1994

Window and Dome Technologies and Materials IV

PROCEEDINGS ARTICLE | September 28, 1994

Engineered polymeric IR-transparent protective coatings

Proc. SPIE. 2286, Window and Dome Technologies and Materials IV

KEYWORDS: Antireflective coatings, Polymers, Interfaces, Gallium arsenide, Optical coatings, Domes, Infrared radiation, Modulation transfer functions, Adhesives, Absorption

Read Abstract

PROCEEDINGS ARTICLE | September 28, 1994

Optical-quality high-growth-rate, arc-jet CVD diamond

Proc. SPIE. 2286, Window and Dome Technologies and Materials IV

KEYWORDS: Diamond, Polishing, Gases, Hydrogen, Diffusion, Chemistry, Chemical vapor deposition, Domes, Plasma, Absorption

Read Abstract

PROCEEDINGS ARTICLE | December 14, 1992

High-resistivity and conductive gallium arsenide for IR optical components

Proc. SPIE. 1760, Window and Dome Technologies and Materials III

KEYWORDS: Optical components, Antireflective coatings, Crystals, Gallium arsenide, Coating, Resistance, Zinc, Domes, Electromagnetic coupling, Absorption

Read Abstract

Infrared (IR) windows and domes for use with electro-optic (EO) systems operating in the 8- to 12-micrometer region are currently fabricated from the following limited number of materials: germanium (Ge), zinc sulfide (ZnS), and a zinc selenide (ZnSe) sandwich. A multiyear development effort at Texas Instruments (TI) has been produced another such material: gallium arsenide (GaAs). A novel crystal growth process has been developed that allows for economical growth of either high-resistivity (10⁷ ohm-cm) or conductive [> 1 (ohm-cm)^-1] GaAs crystals of various thicknesses in sizes up to 12 by 12 inches. This unique growth process permits production of GaAs, which is highly uniform or has a tailored electrical conductivity. With high IR transparency from approximately 1 to 14 micrometers, the high resistivity and conductive GaAs remain operationally useful to 400 degree(s) and 200 degree(s)C, respectively. The low resistivities allow for effective electromagnetic interference (EMI) shielding of 60 dB or more in the gigahertz region in highly transmissive IR windows made of this conductive GaAs. Besides fabrication of traditional precision optical components like lenses and prisms, TI has developed precision fabrication techniques for domes, windows, and segmented windows made of GaAs. These same techniques have also been designed to lower the mean size and distribution of the traditional optical component fabrication flaws, thereby increasing the strength and Weibull modulus of GaAs to 19.1 Kpsi and 4.7, respectively. These high strengths and the corresponding survival probabilities are comparable to those of chemical vapor deposition grown ZnS. TI has also developed techniques to further toughen GaAs, specifically for window and dome applications, in terms of increased strength through increasing the critical stress intensity factor (K_IC) by changing the GaAs microstructure. Toughening in terms of impact resistance to rain during aerodynamic flight has also been developed by means of a protective coating. Antireflective coatings for surface-impedance matching have also been developed. This paper describes the properties of these various GaAs technologies.