OPTICAL SCANNING DEVICE, IMAGE PROJECTION DEVICE, AND MOBILE OBJECT

• US 20190310462A1
• Filed: 04/05/2019
• Published: 10/10/2019
• Est. Priority Date: 04/06/2018
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: YOSHIMURA, Kenichi, NAKAJIMA, Tomohiro
• Granted Patent: US 10,895,739 B2
• Time in Patent Office: Days
• CPC Class Codes: B60K 35/00 Instruments specially adapted for vehicles; Arrangement of instruments in or on vehicles
• CPC Class Codes: B60K 35/23 Head-up displays [HUD] optical aspects of head-up displays G02B27/01
• CPC Class Codes: G01C 21/365 Guidance using head up displays or projectors, e.g. virtual vehicles or arrows projected on the windscreen or on the road itself
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B
• CPC Class Codes: G02B 26/10 Scanning systems
• CPC Class Codes: G02B 26/101 with both horizontal and vertical deflecting means, e.g. raster or XY scanners colour television using laser beams scanning a display screen H04N9/3129
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 7/025 using glue
• CPC Class Codes: G03G 15/043 with means for controlling illumination or exposure G03G15/041 takes precedence
• CPC Class Codes: G09G 5/363 Graphics controllers
• CPC Class Codes: H01L 33/483 Containers

Abstract

An optical scanning device includes: a light source; a scanning unit configured to deflect light from the light source in a main scanning direction to scan a scanned area with light; an optical member configured to guide light from the light source to the scanning unit; a casing holding the light source and the optical member; and an attaching part disposed between the optical member and the casing to attach a part of the optical member to the casing, wherein a direction in which the attaching part is interposed aligns with a direction corresponding to the main scanning direction of the scanning unit.

Claims

1. An optical scanning device comprising:

a light source;

a scanning unit configured to deflect light from the light source in a main scanning direction to scan a scanned area with the light;

an optical member configured to guide the light from the light source to the scanning unit;

a casing holding the light source and the optical member; and

an attaching part disposed between the optical member and the casing to attach a part of the optical member to the casing, wherein

a direction in which the attaching part is disposed is aligned with the main scanning direction of the scanning unit.

2. The optical scanning device according to claim 1, wherein

the attaching part includes an adhesive layer that bonds the optical member to the casing,

the adhesive layer is asymmetrically disposed with respect to an optical axis of the optical member, and

a thickness direction of the adhesive layer is aligned with the direction corresponding to the main scanning direction.

3. The optical scanning device according to claim 1, wherein

the attaching part includes an intermediate holding member bonded to and in contact with the optical member in a direction orthogonal to the main scanning direction, and the intermediate holding member including an intermediate holding member fixing unit that extends to fix the optical member to the casing,

the intermediate holding member fixing unit is asymmetrically disposed with respect to an optical axis of the optical member, and

an extending direction in which the intermediate holding member extends from the intermediate holding member fixing unit to a contact part that contacts the optical member is aligned with the direction corresponding to the main scanning direction.

4. The optical scanning device according to claim 1, further comprising:

a light receiving unit configured to receive light scanned by the scanning unit within a predetermined range of the scanned area; and

a light source controller configured to control a write timing when light from the light source for forming an image starts to be irradiated onto an image forming surface in the scanned area based on a light receiving signal that detects receiving of light by the light receiving unit.

5. The optical scanning device according to claim 4 further comprising a plurality of the light sources, wherein

the light source controller controls the write timing of each of the light sources so as to overlap images formed by light irradiated from the light sources on the image forming surface, and

the light receiving unit sets the write timing among the light sources based on a light receiving signal indicating that the light receiving unit receives light irradiated from one of the light sources.

6. The optical scanning device according to claim 4, wherein the light receiving unit is disposed on both sides of the image forming surface in the main scanning direction to be outside the image forming surface and inside the scanned area.

7. The optical scanning device according to claim 4, wherein the light receiving unit detects a timing of light scanning to an amplitude end passes and a timing at which returned scanning light passes.

8. An image projection device comprising:

an optical scanning unit configured to scan a scanned area with light modulated based on image information;

a projection optical system configured to project light emitted from the optical scanning unit onto a projection surface; and

the optical scanning device, as the optical scanning unit, according to claim 1.

9. A mobile object comprising:

a mobile unit;

an image projection unit configured to project an image onto the projection surface; and

the image projection device, as the image projection unit, according to claim 8.

10. The optical scanning device according to claim 5, wherein the light receiving unit is disposed on both sides of the image forming surface in the main scanning direction to be outside the image forming surface and inside the scanned area.

11. The optical scanning device according to claim 5, wherein the light receiving unit detects a timing of light scanning to an amplitude end passes and a timing at which returned scanning light passes.

12. The optical scanning device according to claim 6, wherein the light receiving unit detects a timing of light scanning to an amplitude end passes and a timing at which returned scanning light passes.

13. The optical scanning device according to claim 10, wherein the light receiving unit detects a timing of light scanning to an amplitude end passes and a timing at which returned scanning light passes.