A-scann.

Brit.

/ˈeɪskan/, U.S.

/ˈeɪˌskæn/

Origin: Formed within English, by compounding. Etymons: A n., scan n.

Etymology: < A n. + scan n., probably originally with reference to A as the first of a set (compare A n. 2a and B-scan n. at B n. Additions), although later often reinterpreted as showing the initial letter of amplitude n. Compare A-scanning n.

A radar or ultrasound scan in which the echo signals are used to generate a linear trace on an oscilloscope screen, the height of a peak being proportional to the strength of the echo; an image obtained by such a scan. Frequently attributive. Cf. B-scan n. at B n. Additions.

ΚΠ

1946 Brit. Patent 583,478 8/2 Means for indicating the range corresponding to a predetermined movement of a strobe-marker on the A scan cathode ray tube screen.

1955 Adv. in Electronics & Electron Physics 7 322 (caption) Solar radio bursts obtained at Sydney:..a type I (storm) burst photographed on ‘A scan’ display.

1996 D. J. Weatherall et al. Oxf. Textbk. Med. (ed. 3) xxiv. 3826/1 An ‘A’ scan can demonstrate midline intracranial structures.

2008 P. N. T. Wells in J. P. McGahan & B. B. Goldberg Diagnostic Ultrasound (ed. 2) I. i. i. 4/1 The A-scan produced by this instrument carries information only about the depths of echo-producing structures and the strengths of the echoes.

This is a new entry (OED Third Edition, June 2011; most recently modified version published online December 2021).

单词	a-scan
释义	A-scann. Brit. /ˈeɪskan/, U.S. /ˈeɪˌskæn/ Origin: Formed within English, by compounding. Etymons: A n., scan n. Etymology: < A n. + scan n., probably originally with reference to A as the first of a set (compare A n. 2a and B-scan n. at B n. Additions), although later often reinterpreted as showing the initial letter of amplitude n. Compare A-scanning n. A radar or ultrasound scan in which the echo signals are used to generate a linear trace on an oscilloscope screen, the height of a peak being proportional to the strength of the echo; an image obtained by such a scan. Frequently attributive. Cf. B-scan n. at B n. Additions. ΚΠ 1946 Brit. Patent 583,478 8/2 Means for indicating the range corresponding to a predetermined movement of a strobe-marker on the A scan cathode ray tube screen. 1955 Adv. in Electronics & Electron Physics 7 322 (caption) Solar radio bursts obtained at Sydney:..a type I (storm) burst photographed on ‘A scan’ display. 1996 D. J. Weatherall et al. Oxf. Textbk. Med. (ed. 3) xxiv. 3826/1 An ‘A’ scan can demonstrate midline intracranial structures. 2008 P. N. T. Wells in J. P. McGahan & B. B. Goldberg Diagnostic Ultrasound (ed. 2) I. i. i. 4/1 The A-scan produced by this instrument carries information only about the depths of echo-producing structures and the strengths of the echoes. This is a new entry (OED Third Edition, June 2011; most recently modified version published online December 2021). < n.1946
随便看	ostracoderm ostracodermal ostracodermatous ostracodermous ostracoderms ostracodes ostracodous ostracods ostracoid ostracological ostracology ostracon ostracophore ostracophorous ostracopod ostracopodous ostracostean ostracosteous ostracothere ostracy ostreaceous ostreal ostrean ostreiculture ostreiculturist