释义 |
Lecher, n.2 Physics.|ˈlɛçə(r), ˈlɛtʃə(r)| Also lecher. The name of Ernst Lecher (1856–1926), Austrian physicist, used attrib. (esp. in Lecher wires) and † in the possessive to designate a pair of parallel wires in which the frequency of a high-frequency electric oscillation may be measured by means of a sliding detector or conductor placed so as to bridge the wires, positions of maximum response or absorption being separated by a distance equal to half the wavelength of the oscillation.
1897Phil. Mag. XLIV. 202 In Lecher's arrangement..the wires are of equal diameter. 1902Encycl. Brit. XXVIII. 59/2 Many problems of electric waves along wires can readily be investigated by a method due to Lecher, and known as Lecher's bridge. 1929J. A. Ratcliffe Physical Princ. Wireless iii. 35 A pair of parallel wires is often used to guide the waves, instead of the single wire... This arrangement is known as the Lecher wire system. 1947Jrnl. Inst. Electr. Engin. XCIV. 953/2 The tuned circuit consisted of a pair of lecher rods, the output being fed through a resonant line to a fixed end⁓fed half-wave vertical aerial. 1962W. B. Thompson Introd. Plasma Physics ii. 12 In arc discharges the electron density is 1011-1012 cm-3 and the plasma frequency ∼ 100 Mc/s, so the high-frequency signals were picked up on resonant Lecher wires, rectified by a crystal and detected by a galvanometer. 1968Radio Communication Handbk. (ed. 4) xix. 12/2 Lecher lines..comprise a pair of taut parallel wires, spaced an inch or so apart to form an open wire transmission line, and a bridge to short circuit the wires which can be moved along the line as required. |