Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Physics
Wide Angle Achromatic Prism Beam Steering For Infrared Countermeasures Applications, Bradley D. Duncan, Philip J. Bos, Vassili Sergan
Wide Angle Achromatic Prism Beam Steering For Infrared Countermeasures Applications, Bradley D. Duncan, Philip J. Bos, Vassili Sergan
Electro-Optics and Photonics Faculty Publications
The design and analysis of achromatic doublet prisms for use in laser beam steering is presented. The geometric relationships describing the maximum steering angle are given, as are discussions of first- and second-order dispersion reduction. Infrared (IR) material alternatives and optimum IR material characteristics for wide-angle achromatic prism beam steering are also investigated. Sixteen materials in 120 different combinations have been examined to date. For midwave IR applications it is shown that the minimum dispersion currently achievable across the full 2 to 5 μm spectrum is 1.7816 mrad at an average maximum steering angle of 45 deg. This is accomplished …
Index-Matched Boundary Techniques For The Elimination Of Acoustical Resonances, Jack H. Parker, Bradley D. Duncan
Index-Matched Boundary Techniques For The Elimination Of Acoustical Resonances, Jack H. Parker, Bradley D. Duncan
Electro-Optics and Photonics Faculty Publications
We extend the principle of optical index of refraction to apply the concept of acoustical index for transverse acoustical wave propagation in strings. The relationship between acoustical index and mass density of the acoustic material is developed. With this theoretical link established, classic index-matching techniques are explored at acoustical boundaries. Proper selection of boundary interface segments leads to the elimination of resonant vibrationalmodes that occur in rigidly supported strings, while maintaining the nonresonant vibration response.