Vibration device and imaging unit including vibration device

Patent metadata

Field	Value
Publication number	US-11433426-B2
Application number	US-202017137505-A
Country	US
Kind code	B2
Filing date	Dec 30, 2020
Priority date	Nov 22, 2019
Publication date	Sep 6, 2022
Grant date	Sep 6, 2022

Abstract

A vibration device includes a protective cover to transmit light with a predetermined wavelength, a first cylindrical body to hold the protective cover at one end, a plate spring to support the other end of the first cylindrical body, a second cylindrical body to support, at one end, a portion of the plate spring in an outer side portion of a portion that supports the first cylindrical body, and a vibrating body that is provided at the other end of the second cylindrical body to vibrate in an axial direction of the second cylindrical body.

First claim

What is claimed is:

1. A vibration device comprising:
a light transmissive body to transmit light with a predetermined wavelength;
a first cylindrical body to hold the light transmissive body at one end;
a plate-shaped spring portion to support another end of the first cylindrical body;
a second cylindrical body to support, at one end, a portion of the spring portion in an outer side portion of a portion that supports the first cylindrical body;
a vibrating body provided at another end of the second cylindrical body to vibrate in an axial direction of the second cylindrical body; and
an excitation circuit to drive the vibrating body; wherein
a resonant frequency of the light transmissive body is larger than a resonant frequency of the spring portion; and
the excitation circuit selectively excites resonance of the light transmissive body and resonance of the spring portion.

2. The vibration device according to claim 1 , wherein
the vibrating body includes:
a vibrating plate extending outward from the another end of the second cylindrical body; and
a piezoelectric element provided on an upper surface or a lower surface of the vibrating plate.

3. The vibration device according to claim 1 , wherein
the vibrating body includes:
a plate-shaped vibrating plate extending inward from the another end of the second cylindrical body; and
a piezoelectric element provided on an upper surface or a lower surface of the vibrating plate.

4. The vibration device according to claim 1 , wherein a resonant frequency of the light transmissive body is equal to or more than about 1.2 times a resonant frequency of the spring portion.

5. The vibration device according to claim 1 , wherein the excitation circuit drives the vibrating body so that the first cylindrical body and the second cylindrical body vibrate in opposite phase from one another in an axial direction.

6. The vibration device according to claim 1 , wherein at least one of the light transmissive body, the first cylindrical body, the spring portion, the second cylindrical body, and the vibrating body has a circular or substantially circular shape when the first cylindrical body is viewed from the axial direction.

7. The vibration device according to claim 1 , wherein at least one of the light transmissive body, the first cylindrical body, the spring portion, the second cylindrical body, and the vibrating body has a rectangular or substantially rectangular shape when the first cylindrical body is viewed from the axial direction.

8. The vibration device according to claim 1 , wherein the light transmissive body has a dome shape.

9. The vibration device according to claim 1 , wherein the light transmissive body has a plate shape.

10. An imaging unit comprising:
the vibration device according to claim 1 ; and
an imaging element arranged so that the light transmissive body is in a field of view direction.

11. A vibration device comprising:
a light transmissive body to transmit light with a predetermined wavelength;
a first cylindrical body to hold the light transmissive body at one end;
a plate-shaped spring portion to support another end of the first cylindrical body;
a second cylindrical body to support, at one end, a portion of the spring portion in an outer side portion of a portion that supports the first cylindrical body; and
a vibrating body provided at another end of the second cylindrical body to vibrate in an axial direction of the second cylindrical body; wherein
a thickness of the first cylindrical body is shorter than a length from a position of the spring portion that supports the first cylindrical body to a position of the spring portion that is supported by the second cylindrical body.

12. The vibration device according to claim 11 , wherein
a resonant frequency of the light transmissive body is larger than a resonant frequency of the spring portion;
an excitation circuit to drive the vibrating body is further included; and
the excitation circuit selectively excites resonance of the light transmissive body and resonance of the spring portion.

13. A vibration device comprising:
a light transmissive body to transmit light with a predetermined wavelength;
a first cylindrical body to hold the light transmissive body at one end;
a plate-shaped spring portion to support another end of the first cylindrical body;
a second cylindrical body to support, at one end, a portion of the spring portion in an outer side portion of a portion that supports the first cylindrical body; and
a vibrating body provided at another end of the second cylindrical body to vibrate in an axial direction of the second cylindrical body; wherein
the vibrating body includes:
a vibrating plate extending outward from the another end of the second cylindrical body; and
a piezoelectric element provided on an upper surface or a lower surface of the vibrating plate; and

the vibrating body includes the vibrating plate that is provided with the piezoelectric element integrally provided along a shape of the vibrating plate.

14. A vibration device comprising:
a light transmissive body to transmit light with a predetermined wavelength;
a first cylindrical body to hold the light transmissive body at one end;
a plate-shaped spring portion to support another end of the first cylindrical body;
a second cylindrical body to support, at one end, a portion of the spring portion in an outer side portion of a portion that supports the first cylindrical body; and
a vibrating body provided at another end of the second cylindrical body to vibrate in an axial direction of the second cylindrical body; wherein
the vibrating body includes:
a vibrating plate extending outward from the another end of the second cylindrical body; and
a piezoelectric element provided on an upper surface or a lower surface of the vibrating plate;

the vibrating body includes a plurality of the rectangular or substantially rectangular piezoelectric elements provided along a shape of the vibrating plate.

15. An imaging unit comprising:
a vibration device including:
a light transmissive body to transmit light with a predetermined wavelength;
a first cylindrical body to hold the light transmissive body at one end;
a plate-shaped spring portion to support another end of the first cylindrical body;
a second cylindrical body to support, at one end, a portion of the spring portion in an outer side portion of a portion that supports the first cylindrical body;
a vibrating body provided at another end of the second cylindrical body to vibrate in an axial direction of the second cylindrical body; and
an excitation circuit to drive the vibrating body; and

an imaging element arranged so that the light transmissive body is in a field of view direction; wherein
a resonant frequency of the light transmissive body is larger than a resonant frequency of the spring portion;
and
the excitation circuit selectively excites resonance of the light transmissive body and resonance of the spring portion.

16. The imaging unit according to claim 15 , wherein
the vibrating body includes:
a vibrating plate extending outward from the another end of the second cylindrical body; and
a piezoelectric element provided on an upper surface or a lower surface of the vibrating plate.

17. The imaging unit according to claim 15 , wherein
the vibrating body includes:
a plate-shaped vibrating plate extending inward from the another end of the second cylindrical body; and
a piezoelectric element provided on an upper surface or a lower surface of the vibrating p

Assignees

• Murata Manufacturing Co

Inventors

• Fujimoto Katsumi
• Ishii Yuuki
• Sakaguchi Hitoshi

Classifications

• H04N23/50 Primary

  Constructional details · CPC title

• H04N23/52

  Elements optimising image sensor operation, e.g. for electromagnetic interference [EMI] protection or temperature control by heat transfer or cooling elements · CPC title

• B06B1/0644

  using a single piezoelectric element (B06B1/0688 takes precedence) · CPC title

• B06B1/0207

  Driving circuits (specially adapted for particular applications, see the relevant subclass, e.g. G01; circuits for steering transducer arrays G10K11/34; basic circuits H03) · CPC title

• G02B7/026

  using retaining rings or springs (G02B7/027 takes precedence) · CPC title