Optical scanning device, projection device, and display device

Patent metadata

Field	Value
Publication number	US-10587849-B2
Application number	US-201715635527-A
Country	US
Kind code	B2
Filing date	Jun 28, 2017
Priority date	Jul 6, 2016
Publication date	Mar 10, 2020
Grant date	Mar 10, 2020

Abstract

An optical scanning device includes a light source, a scanning member, and an incident optical system. The scanning member two-dimensionally scans a scanning area with the deflected light beam in a first direction and a second direction perpendicular to the first direction. The incident optical system guides the emitted light beam to the scanning member, the incident optical system including the light source. The scanning area includes a first area and a second area surrounding the first area. When the scanning area is viewed from a side of the scanning member, at least a part of the incident optical system is disposed in an area of the second area that overlaps one of two divided areas of the scanning area. The two divided areas are divided by a line segment parallel to the first direction.

First claim

What is claimed is:

1. An optical scanning device comprising:
a light source to emit a light beam;
a scanning member to deflect the light beam emitted from the light source to cause the deflected light beam to two-dimensionally scan a scanning area in a first direction and a second direction perpendicular to the first direction; and
an incident optical system to guide the light beam emitted from the light source to the scanning member, the incident optical system including the light source and an optical element,
wherein the scanning area includes a first area and a second area surrounding the first area, the first area being an image-forming area in which an intermediate image is formed and the second area being a non-image-forming area in which no intermediate image is formed,
wherein, when the scanning area is viewed from a side of the scanning member, the scanning area is divided into two divided areas by a line segment parallel to the first direction, and at least a part of a component that constitutes the incident optical system is disposed in an area of the second area that overlaps one of two divided areas of the scanning area, and
wherein the at least the part of the component that constitutes the incident optical system is disposed between the scanning member and the scanning area along a scanning optical path such that the light beam in the scanning optical path intersects the at least the part of the component that constitutes the incident optical system, the scanning optical path being an optical path in which the light beam deflected by the scanning member travels to the scanning area when the scanning member scans.

2. The optical scanning device according to claim 1 , further comprising a sensor to detect a synchronization of deflecting and scanning of the scanning member,
wherein the sensor is disposed in the area of the second area that overlaps one of two divided areas of the scanning area, and
wherein the at least a part of the component is disposed side-by-side with the sensor in a direction parallel to the first direction, in the area of the second area that overlaps one of two divided areas of the scanning area when the scanning area is viewed from the side of the scanning member.

3. The optical scanning device according to claim 2 ,
wherein the sensor is disposed in a vicinity of an end of the first area in the first direction, outside the first area in the second direction, in the area of the second area that overlaps one of two divided areas of the scanning area, and
wherein the at least a part of the incident optical system is disposed closer to a center of the second area in the first direction than the sensor, outside the first area in the second direction, in the area of the second area that overlaps one of two divided areas of the scanning area.

4. The optical scanning device according to claim 3 , further comprising another sensor different from the sensor,
wherein said another sensor is disposed in a vicinity of other end other than the end of the first area in the first direction, outside the first area in the second direction, in the area of the second area that overlaps one of two divided areas of the scanning area, and
wherein the at least a part of the incident optical system are disposed between the sensor and said another sensor in the first direction, outside the first area in the second direction, in the area of the second area that overlaps one of two divided areas of the scanning area.

5. The optical scanning device according to claim 1 ,
wherein the first direction is a main scanning direction of the scanning area, and
wherein the second direction is a sub-scanning direction of the scanning area.

6. The optical scanning device according to claim 1 ,
wherein the at least a part of the component is the optical element.

7. The optical scanning device according to claim 6 ,
wherein the optical element is a lens.

8. The optical scanning device according to claim 7 ,
wherein the lens is a meniscus lens that has a concave surface toward the scanning member.

9. The optical scanning device according to claim 1 ,
wherein the at least part of the component is a holding member to hold the optical element in the incident optical system.

10. The optical scanning device according to claim 9 ,
wherein the optical element is a lens.

11. The optical scanning device according to claim 10 ,
wherein the lens is a meniscus lens that has a concave surface toward the scanning member.

12. A projection device comprising the optical scanning device according to claim 1 to project an image formed by the scanning member scanning the first area with the light beam emitted from the light source.

13. A display device comprising the optical scanning device according to claim 1 to display an image formed by the scanning member scanning the first area with the light beam emitted from the light source.

Assignees

• Hayashi Yuki
• Ricoh Co Ltd

Inventors

• Hayashi Yuki

Classifications

• G02B27/0172

  characterised by optical features · CPC title

• G02B26/101 Primary

  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 title

• G02B2027/0161

  characterised by the relative positioning of the constitutive elements · CPC title

• G02B2027/015

  involving arrangement aiming to get less bulky devices · CPC title

• H04N9/3129 Primary

  scanning a light beam on the display screen (scanning a light beam on a screen in displays other than projection devices G09G3/02; scanning systems in general G02B26/10; projectors using laser light sources in general H04N9/3161) · CPC title