An acoustic wave device includes a piezoelectric layer, first and second upper electrodes, first and second lower electrodes, and first and second acoustic reflection films. In plan view, first and second resonator portions are respectively defined by portions where the first upper electrode and the first lower electrode overlap and where the second upper electrode and the second lower electrode overlap. The first and second acoustic reflection films respectively include first and second metal layers. First and second overlapping portions are respectively defined by portions where only the first upper electrode overlaps with the first metal layer and where only the second upper electrode overlaps with the second metal layer. An area of the first resonator portion is smaller than an area of the second resonator portion and an area of the first overlapping portion is larger than an area of the second overlapping portion.

An acoustic wave device includes a piezoelectric layer, first and second upper electrodes, first and second lower electrodes, and first and second acoustic reflection films. In plan view, first and second resonator portions are respectively defined by portions where the first upper electrode and the first lower electrode overlap and where the second upper electrode and the second lower electrode overlap. The first and second acoustic reflection films respectively include first and second metal layers. First and second overlapping portions are respectively defined by portions where only the first upper electrode overlaps with the first metal layer and where only the second upper electrode overlaps with the second metal layer. An area of the first resonator portion is smaller than an area of the second resonator portion and an area of the first overlapping portion is larger than an area of the second overlapping portion.

An oscillating device includes a first quartz crystal resonator, a driving circuit, a first waveform adjustment circuit, and at least two second quartz crystal resonators. The first quartz crystal resonator has a first resonant frequency. The driving circuit, coupled to the first quartz crystal resonator, drives the first quartz crystal resonator to generate a first oscillating signal having the first resonant frequency. The second quartz crystal resonators, coupled in parallel and coupled to the driving circuit and the first quartz crystal resonator, have a second resonant frequency and receive and rectify the first oscillating signal to generate a second oscillating signal having the second resonant frequency. The first waveform adjustment circuit, coupled to the second quartz crystal resonators, receives the second oscillating signal and adjusts the second oscillating signal to generate a first waveform adjustment signal.

An oscillating device includes a first quartz crystal resonator, a driving circuit, a first waveform adjustment circuit, and at least two second quartz crystal resonators. The first quartz crystal resonator has a first resonant frequency. The driving circuit, coupled to the first quartz crystal resonator, drives the first quartz crystal resonator to generate a first oscillating signal having the first resonant frequency. The second quartz crystal resonators, coupled in parallel and coupled to the driving circuit and the first quartz crystal resonator, have a second resonant frequency and receive and rectify the first oscillating signal to generate a second oscillating signal having the second resonant frequency. The first waveform adjustment circuit, coupled to the second quartz crystal resonators, receives the second oscillating signal and adjusts the second oscillating signal to generate a first waveform adjustment signal.

An oscillating device includes a first quartz crystal resonator, a driving circuit, a first waveform adjustment circuit, and at least two second quartz crystal resonators. The first quartz crystal resonator has a first resonant frequency. The driving circuit, coupled to the first quartz crystal resonator, drives the first quartz crystal resonator to generate a first oscillating signal having the first resonant frequency. The second quartz crystal resonators, coupled in parallel and coupled to the driving circuit and the first quartz crystal resonator, have a second resonant frequency and receive and rectify the first oscillating signal to generate a second oscillating signal having the second resonant frequency. The first waveform adjustment circuit, coupled to the second quartz crystal resonators, receives the second oscillating signal and adjusts the second oscillating signal to generate a first waveform adjustment signal.

An oscillating device includes a first quartz crystal resonator, a driving circuit, a first waveform adjustment circuit, and at least two second quartz crystal resonators. The first quartz crystal resonator has a first resonant frequency. The driving circuit, coupled to the first quartz crystal resonator, drives the first quartz crystal resonator to generate a first oscillating signal having the first resonant frequency. The second quartz crystal resonators, coupled in parallel and coupled to the driving circuit and the first quartz crystal resonator, have a second resonant frequency and receive and rectify the first oscillating signal to generate a second oscillating signal having the second resonant frequency. The first waveform adjustment circuit, coupled to the second quartz crystal resonators, receives the second oscillating signal and adjusts the second oscillating signal to generate a first waveform adjustment signal.

Provided is a crystal element that includes: a crystal piece that is in a substantially rectangular shape on a plan view; an excitation electrode part located on both main surfaces of the crystal piece; a connection lead part extended to a first short-side of the crystal piece from the excitation electrode part; a convex part located on both ends of a second short-side of the crystal piece; and a projected part located on both ends of the first short-side of the crystal piece. Further, a concave part is located in the convex part, and a recessed part is located in the projected part.

Provided is a crystal element that includes: a crystal piece that is in a substantially rectangular shape on a plan view; an excitation electrode part located on both main surfaces of the crystal piece; a connection lead part extended to a first short-side of the crystal piece from the excitation electrode part; a convex part located on both ends of a second short-side of the crystal piece; and a projected part located on both ends of the first short-side of the crystal piece. Further, a concave part is located in the convex part, and a recessed part is located in the projected part.

A vibration element includes: a base; a first arm continuous with the base; a second arm that is continuous with the base and is adjacent to the first arm; a first electrode disposed on the first arm, the second arm, and the base; a first piezoelectric layer that has a first polarity and that is disposed on the first electrode on the first arm; a second piezoelectric layer that has a second polarity different from the first polarity and that is disposed on the first electrode on the second arm; an insulating layer disposed on the first electrode on the base; and a second electrode disposed on the first piezoelectric layer, the second piezoelectric layer, and the insulating layer.

A vibration element includes: a base; a first arm continuous with the base; a second arm that is continuous with the base and is adjacent to the first arm; a first electrode disposed on the first arm, the second arm, and the base; a first piezoelectric layer that has a first polarity and that is disposed on the first electrode on the first arm; a second piezoelectric layer that has a second polarity different from the first polarity and that is disposed on the first electrode on the second arm; an insulating layer disposed on the first electrode on the base; and a second electrode disposed on the first piezoelectric layer, the second piezoelectric layer, and the insulating layer.