Rayleigh distance Rayleigh distance Rayleigh distance in optics is the axial distance from a radiating aperture to a point at which the path difference between the axial ray and an edge ray is λ / 4. An approximation of the Rayleigh Distance is formula_1, in which Z is the Rayleigh distance, D is the aperture of radiation, λ the wavelength. This approximation can be derived as follows. Consider a right angled triangle with sides adjacent formula_2, opposite formula_3and hypotenuse formula_4. According to Pythagorean theorem, formula_5. Rearranging, and simplifying formula_6 The constant termformula_7 can be neglected. In antenna applications, the Rayleigh distance is
What Sound not feature the track "Written". 2002 Australian limited edition What Sound What Sound is the third album by English electronic music group Lamb, released in October 2001 Original members Andy Barlow and Lou Rhodes are joined by session musicians Arto Lindsay on guitar, Me'Shell NdegéOcello on bass, and Michael Franti with additional vocal work. Doves guitarist Jimi Goodwin, producers Nellee Hooper and Richard Dorfmeister (one half of Kruder & Dorfmeister) also contributed to the album. The track "Heaven" was used constantly on the HBO television series "Six Feet Under". A hidden track called "Blessing in Disguise" follows a period of