This thesis deals with the precise measurement of distances in nanometer range at ultrasonic frequencies for the purposes of vibrometry. The paper is primary focused on~nanometric displacement measurement methods. First the thesis deals with the physical phenomena based on light in the theoretical section. This includes interference of light, index of refraction, polarization, interferometry and more. Understanding of these physical laws is crucial for design and assembling of the interferometer. Subjects of interferometric method for precise and fast measurement of the nanometric displacement and vibration are discussed. Interferometer components such as lasers, photodetectors and optical elements are described are described in the final part of this section. Practical section of thesis can be divided into two parts. The design and assembling issues are discussed in the first section. Many problems which I had to solve are described. Control software and implementation of the signal processing is the subject of the second part. I met with particular problems such as phase unwrapping. I solved this problem of discontinuous phase field with user written algorithm. Finally the graphical user interface was created. Using assembled interferometer and written software application I measured vibration of Langevin transducer on ultrasonic frequencies.

It is desirable to modify the spectral signature of a surface, particularly in the infrared (IR) region of the electromagnetic spectrum. To alter the surface signature in the IR, two methods are investigated: thin film application and antenna array application. The former approach is a common and straightforward incorporation of optically-thin film coatings on the surface designated for signature modification. The latter technique requires the complex design of a periodic array of passive microantenna elements to cover the surface in order to modify its signature. This technology is known as frequency selective surface (FSS) technology and is established in the millimeter-wave spectral regime, but is a challenging technology to scale for IR application. Incorporation of thin films and FSS antenna elements on a surface permits the signature of a surface to be changed in a deterministic manner. In the seminal application of this work, both technologies are integrated to comprise a circuit-analog absorbing IR FSS. The design and modeling of surface treatments are accomplished using commercially-available electromagnetic simulation software. Fabrication of microstructured antenna arrays is accomplished via microlithographic technology, particularly using an industrial direct-write electron-beam lithography system. Comprehensive measurement methods are utilized to study the patterned surfaces, including infrared spectral radiometry and Fourier-transform infrared spectrometry. These systems allow for direct and complementary spectral signature measurements--the radiometer measures the absorption or emission of the surface, and the spectrometer measures its transmission and reflection. For the circuit-analog absorbing square-loop IR FSS, the spectral modulation in emission is measured to be greater than 85% at resonance. Other desirable modifications of surface signature are also explored; these include the ability to filter radiation based on its polarization orientation and the ability to dynamically tune the surface signature. An array of spiral FSS elements allows for circular polarization conditioning. Three techniques for tuning the IR FSS signature via voltage application are explored, including the incorporation of a pn junction substrate, a piezoelectric substrate and a liquid crystal superstrate. These studies will ignite future explorations of IR FSS technology, enabling various unique applications.

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