Photonic Crystal Enhancement
Photonic Crystal Enhancement is a dynamic research enterprise. We are developing photonic crystal design and fabrication approaches to improve the performance of current infrared MEMS chips while improving production yields, shrinking die size, and ultimately reducing die costs. At the same time, we are conducing fundamental research – extreme IR emitter materials, spatial and spectral coherence, active electronic modulation – to provide radically new products and applications.
A photonic crystal is a periodic medium which is opaque to light of certain wavelengths travelling in certain directions, much the same way that electrons are forbidden at energy levels within the electrical band gap of a semiconductor device. The physical parameters of the medium, such as film thickness and material dielectric constant, determine what wavelengths are forbidden. A thin-film Bragg grating is a one-dimensional photonic crystal for incident light at the correct wavelength which strikes the grating perpendicular to the surface. Light is reflected by each surface of all films that compose the grating and the light waves interfere destructively to produce useful properties like reflection or absorption.
A two-dimensional photonic band gap is formed by creating a periodic 2-D pattern of features in a metal or dielectric layer. In the 2-D case, the edges of the etched features act as interfaces that refract and reflect incident light. Two dimensional structures can serve as a transmission filter for light at the correct wavelength. Some two dimensional structures completely block light transmission in the plane of the surface and these structures have been developed as waveguides, by designing the refractive index of the material, and the size and period of the features.
Large Area IR Scene Projector
Remote IR Calibration Target
Extreme SiC Emitters
Photonic Crystal Coherent Emission for Sensors
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