Vibration elements

• US 8,199,389 B2
• Filed: 03/10/2009
• Issued: 06/12/2012
• Est. Priority Date: 03/10/2008
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Saitoh, Tetsurou, Sato, Yukito, Eiji, Mochizuki
• Primary Examiner(s): FONT, FRANK G
• Application Number:
  US12/400,911
• Publication Number:
  US 20090225384A1
• Time in Patent Office: 1,190 Days
• Field of Search: 3591961-1991, 359/201.1, 359/201.2, 359/212.1, 359/213.1, 359/221.2, 359/223.1, 359/224.1
• US Class Current: 359/213.1
• CPC Class Codes: B81B 2201/047 Optical MEMS not provided for in B81B2201/042 - B81B2201/045
• CPC Class Codes: B81C 1/00682 Treatments for improving mechanical properties, not provided for in B81C1/00658 - B81C1/0065
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means

Abstract

A vibration unit including a frame, a vibration element including a substrate configured to vibrate, and a beam configured to connect the vibration element to the frame. The vibration unit is produced by applying an etching process to at least two surfaces of a substrate. A meeting position of the two surfaces of the substrate is located where a first etching process, which takes place on a first surface of the substrate and a second etching process, which takes place on a second surface of the substrate meet, and is located at a position other than a center position in a width direction of the beam.

Claims

1. A vibration unit, comprising:

a frame;

a vibration element configured to vibrate and with a substrate having a first etched surface formed on a top surface of the substrate and a second etched surface formed on a bottom surface of the substrate, the first etched surface and the second etched surface communicate with each other at a meeting point located at a position other than a center position in a thickness direction of the substrate of the vibration element; and

a beam connecting the vibration element to the frame.

2. The vibration unit according to claim 1,

wherein the meeting point is located at a position which is more than d/4 apart from the center position of the vibration element, wherein d is a measured thickness of the vibration element.

3. The vibration unit according to claim 1,

wherein a width of the beam between the second etched surface and the meeting point is larger than a width of the beam between the first etched surface and the meeting point.

8. The vibration unit according to claim 1,

wherein the vibration element has a reflective coating including a titanium layer, a platinum layer, and a gold layer.

9. The vibration unit according to claim 8,

wherein the platinum layer has a thickness of 0.05 μ

m.

10. The vibration unit according to claim 8,

wherein the gold layer has a thickness of 0.05 μ

m.

11. The vibration unit according to claim 1,

wherein the vibration unit includes two pairs of ribs which are indentations formed in the substrate on an opposite side of a surface containing a reflective coating.

12. The vibration unit according to claim 1,

wherein the beam includes two etched surfaces.

13. The vibration unit according to claim 1,

wherein an upper-most portion of the frame is located higher than an upper-most position of the vibration element.

4. A vibration unit, comprising:

a frame;

a vibration element configured to vibrate and with a substrate having a first etched surface formed on a top surface of the substrate and a second etched surface formed on a bottom surface of the substrate, the first etched surface and the second etched surface communicate with each other at a meeting point located at a position other than a center position in a thickness direction of the substrate of the vibration element; and

a beam connecting the vibration element to the frame, and the beam has a first surface on a top portion of the beam and a second surface on a bottom portion of the beam, and a width of the beam at the first surface is smaller than a width of the beam at the second surface.

5. The vibration unit according to claim 4,

wherein the beam has a first height from the second surface to a meeting point larger than a second height from the first surface to the meeting point, wherein the meeting point is located where a first etching process, which takes place on the first surface of the substrate, and a second etching process, which takes place on the second surface of the substrate, meet.

6. The vibration unit according to claim 5,

wherein the meeting position is located at the end of the beam in a width direction of the beam.

7. The vibration unit according to claim 6,

wherein the vibration element is an optical unit that includes a reflection unit configured to reflect light.