Optical scanner having a variable focus mirror

Patent metadata

Field	Value
Publication number	US-10108005-B2
Application number	US-201514831996-A
Country	US
Kind code	B2
Filing date	Aug 21, 2015
Priority date	Aug 21, 2014
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

An optical scanner includes a substrate having a rigid body and a beam, and a layered body having multiple layers, including a lower conductive layer, a interlayer insulation film and an upper conductive layer, the layered body layered on and protruding outward from the rigid body and the beam. The layered body is patterned to form a resonance scanner portion and a vari-focal mirror, the resonance scanner portion (i) made as a part of the layered body and (ii) having an actuator part, and the vari-focal mirror made as a part of the layered body. The layered body including the resonance scanner portion and the vari-focal mirror is patterned to form a mirror driving wire. In such structure, the size of the optical scanner is reduced, and a frequency change of the resonance scanner portion due to the voltage application to the mirror driving wire is suppressed.

First claim

What is claimed is:

1. An optical scanner comprising:
a substrate forming a rigid body and a beam; and
a layered body formed on the rigid body and the beam and a portion of the layered body overhanging the rigid body and the beam, the layered body having multiple layers including a lower conductive layer, an interlayer insulation film, and an upper conductive layer, the interlayer insulation film in contact with and sandwiched between the lower conductive layer and the upper conductive layer, wherein
a portion of the layered body is patterned to form a resonance scanner portion, the resonance scanner portion formed on the rigid body and on a portion of the beam, the resonance scanner portion having a protruding portion that protrudes away from the rigid body and toward the beam to form an actuator part, and wherein
a portion of the layered body is patterned to form a vari-focal mirror on a remaining portion of the beam, a portion of the vari-focal mirror protruding away from the beam toward the rigid body, and wherein
a portion of the layered body is patterned to form a mirror driving wire, the mirror driving wire extending through and insulated from the resonance scanner portion to connect to the vari-focal mirror, the mirror driving wire configured to provide a drive voltage directly to the layered body directly at the vari-focal mirror to control a focus of the vari-focal mirror, and wherein
the interlayer insulation film of the resonance scanner portion is made from a piezoelectric film, and wherein
the interlayer insulation film of the mirror driving wire is made from a non-piezoelectric insulation film.

2. The optical scanner of claim 1 , wherein
the interlayer insulation film of the mirror driving wire extending through at least the actuator part of the resonance scanner portion is made from the non-piezoelectric insulation film.

3. The optical scanner of claim 1 , wherein
the non-piezoelectric insulation film in the mirror driving wire is made either by an ion injection method or by a laser annealing method.

4. The optical scanner of claim 1 , wherein
the mirror driving wire is electrically insulated from the resonance scanner portion by a groove between the interlayer insulation film and the upper conductive layer of the mirror driving wire and the interlayer insulation film and the upper conductive layer of the resonance scanner portion.

5. An optical scanner comprising:
a substrate forming a rigid body and a beam, the substrate made of a semiconductor material; and
a layered body formed on the rigid body and the beam and a portion of the layered body overhanging the rigid body and the beam, the layered body having multiple layers including a lower conductive layer, an interlayer insulation film, and an upper conductive layer, the interlayer insulation film in contact with and sandwiched between the lower conductive layer and the upper conductive layer, wherein
a portion of the layered body is patterned to form a resonance scanner portion, the resonance scanner portion formed on the rigid body and on a portion of the beam, the resonance scanner portion having a protruding portion that protrudes away from the rigid body and toward the beam to form an actuator part, and wherein
a portion of the layered body is patterned to form a vari-focal mirror on a remaining portion of the beam, a portion of the vari-focal mirror protruding away from the beam toward the rigid body, and wherein
a non-conductive film is interposed between the layered body and the substrate, and wherein
a part of the substrate under the resonance scanner portion is doped with impurities to form at least one diffusion layer, the at least one diffusion layer configured to form a mirror driving wire extending through the substrate and under the resonance scanner portion to connect to the vari-focal mirror, the mirror driving wire configured to provide a drive voltage directly to the layered body directly at the vari-focal mirror to control a focus of the vari-focal mirror.

6. The optical scanner of claim 5 , wherein
a thickness of the substrate varies such that the thickness of the substrate under the actuator part is thinner than the thickness of the rigid body, and wherein
the mirror driving wire is formed to pass under the actuator part.

7. An optical scanner comprising:
a substrate forming a rigid body and a beam; and
a layered body formed on the rigid body and the beam and a portion of the layered body overhanging the rigid body and the beam, the layered body having multiple layers including a lower conductive layer, an interlayer insulation film, and an upper conductive layer, the interlayer insulation film in contact with and sandwiched between the lower conductive layer and the upper conductive layer, wherein
a portion of the layered body is patterned to form a resonance scanner portion, the resonance scanner portion formed on the rigid body and on a portion of the beam, the resonance scanner portion having a protruding portion that protrudes away from the rigid body and toward the beam to form an actuator part, and wherein
a portion of the layered body is patterned to form a vari-focal mirror on a remaining portion of the beam, a portion of the vari-focal mirror protruding away from the beam toward the rigid body, and wherein
a portion of the layered body is patterned to form a mirror driving wire, the mirror driving wire extending through and insulated from the resonance scanner portion to connect to the vari-focal mirror, the mirror driving wire configured to provide a drive voltage directly to the layered body directly at the vari-focal mirror to control a focus of the vari-focal mirror, and wherein
the interlayer insulation film of the resonance scanner portion and the mirror driving wire is made from a piezoelectric film, and wherein
when the drive voltage is provided to the vari-focal mirror, the resonance scanner portion receives a resonance scanning voltage that includes a reverse phase signal that cancels a resonance frequency change in the resonance scan portion caused by the drive voltage.

8. The optical scanner of claim 7 , wherein
the mirror driving wire is electrically insulated from the resonance scanner portion by a groove between the interlayer insulation film and the upper conductive layer of the mirror driving wire and the interlayer insulation film and the upper conductive layer of the resonance scanner portion.

Assignees

• Denso Corp

Inventors

• Kawai Yusuke
• Sakai Kenichi
• Oyama Koichi
• Nishikawa Hideaki

Classifications

• G02B26/0858

  the reflecting means being moved or deformed by piezoelectric means · CPC title

• G02B26/0825 Primary

  the reflecting element being a flexible sheet or membrane, e.g. for varying the focus (flexible mirrors for cosmetic use A45D42/24) · CPC title

• B81B3/0078

  Constitution or structural means for improving mechanical properties not provided for in B81B3/007 - B81B3/0075 · CPC title

• B81B3/00

  Devices comprising flexible or deformable elements, e.g. comprising elastic tongues or membranes (B81B5/00 takes precedence) · CPC title

• B81B2201/042

  Micromirrors, not used as optical switches · CPC title