CRYSTAL FILTER PLATE, AND CRYSTAL FILTER

• Main Author: KODA NAOKI
• Format: Patent
• Language: English; Japanese
• Published: 11.01.2018
• Subjects: BASIC ELECTRONIC CIRCUITRY; ELECTRICITY; IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS

PROBLEM TO BE SOLVED: To provide a crystal filter plate having a wiring structure of a higher-reliability extraction electrode in which disconnection is unlikely to occur, and a crystal filter at lower cost.SOLUTION: A crystal filter comprises: an AT cut crystal filter plate 5 having a tabular shape that is rectangular in a planar view, with an X axis and a Z axis defined as sides and including a thin vibration part 53 in the center, a thick outer frame part 54 in a circumference and a step wall 56 connecting the vibration part with the outer frame part; a split electrode which is formed on one principal surface of the crystal filter plate and in such a first electrode 501 and a second electrode 502 are formed side by side; a common electrode 503 which is formed on the other principal surface of the crystal filter plate and formed oppositely to the split electrode; and extraction electrodes 504, 505, 506 and 507 connected with the electrodes and extending from the vibration part to a portion of the outer frame part. In the step wall, uneven surface step wall parts 5691, 5692, 5693 and 5694 are formed in portions where the extraction electrodes 506 and 507 pass.SELECTED DRAWING: Figure 1 【課題】 より安価に断線が生じにくいより信頼性の高い引出電極の配線構造を有する水晶フィルタ板、および水晶フィルタを提供する。【解決手段】 Ｘ軸とＺ′軸を各辺とした平面視矩形板状で、中央の薄肉の振動部５３と、外周の厚肉の外枠部５４と、振動部と外枠部とをつなぐ段差壁５６とを有するＡＴカットの水晶フィルタ板５と、水晶フィルタ板の一主面に形成されＺ′軸に沿って第１電極５０１と第２電極５０２とが並んで形成された分割電極と、水晶フィルタ板の他主面に形成され分割電極に対向して形成された共通電極５０３と、上記各電極と接続され振動部から外枠部の一部へと延出される各引出電極５０４，５０５，５０６，５０７とを備えており、上記段差壁のうち引出電極５０６，５０７が通過する部分には、凹凸面状段差壁部５６９１，５６９２，５６９３，５６９４が形成されている。【選択図】 図１