Scanning optical system and light projecting and receiving apparatus

Patent metadata

Field	Value
Publication number	US-10162171-B2
Application number	US-201515518200-A
Country	US
Kind code	B2
Filing date	Oct 6, 2015
Priority date	Oct 9, 2014
Publication date	Dec 25, 2018
Grant date	Dec 25, 2018

Abstract

A scanning optical system, includes a mirror unit having a first mirror surface and a second mirror surface which incline to a rotation axis; and a light projecting system having a light source. A light flux emitted from the light source is reflected on the first mirror surface of the mirror unit, thereafter, reflected on the second mirror surface, and then, projected so as to scan in a main scanning direction onto an object in accordance with rotation of the mirror unit. In the case where a virtual plane is set in a range including the object, a light flux reflected on the second mirror surface has, upon entering the virtual plane, a cross sectional shape in which a length in a direction orthogonal to the main scanning direction is longer than a length in the main scanning direction.

First claim

The invention claimed is:

1. A scanning optical system, comprising:
a mirror unit equipped with a first mirror surface and a second mirror surface each of which inclines to a rotation axis; and
a light projecting system including at least one light source to emit a light flux toward the first mirror surface,
wherein a light flux emitted from the light source is reflected on the first mirror surface of the mirror unit, thereafter, reflected on the second mirror surface, and then, projected so as to scan in a main scanning direction onto an object in accordance with rotation of the mirror unit, and
wherein the light flux toward the object has a cross sectional shape in a plane orthogonal to a direction toward the object in which a length in a direction orthogonal to the main scanning direction is longer than a length in the main scanning direction.

2. The scanning optical system described in claim 1 , wherein the mirror unit includes a plurality of pairs of the first mirror surface and the second mirror surface, and an intersection angle between the first mirror surface and the second mirror surface in each pair is different from respective intersection angles of the other pairs.

3. The scanning optical system described in claim 1 , wherein the mirror unit includes a plurality of pairs of the first mirror surface and the second mirror surface, and the plurality of pairs includes at least two pairs which have the same intersection angle between the first mirror surface and the second mirror surface and at least one pair which has an intersection angle different from the intersection angle of the two pairs.

4. The scanning optical system described in claim 1 , further comprising:
a deflecting element which is disposed between the light source and the mirror unit and changes a proceeding direction of a light flux emitted from the light source.

5. The scanning optical system described in claim 1 , wherein the light source has a light emitting surface in which a length along the rotation axis is linger than a length in a direction orthogonal to the rotation axis.

6. A light projecting and receiving apparatus, comprising:
a scanning optical system comprising:
a mirror unit equipped with a first mirror surface and a second mirror surface each of which inclines to a rotation axis; and
a light projecting system including at least one light source to emit a light flux toward the first mirror surface,
wherein a light flux emitted from the light source is reflected on the first mirror surface of the mirror unit, thereafter, reflected on the second mirror surface, and then, projected so as to scan in a main scanning direction onto an object in accordance with rotation of the mirror unit, and
wherein the light flux toward the object has a cross sectional shape in a plane orthogonal to a direction toward the object in which a length in a direction orthogonal to the main scanning direction is longer than a length in the main scanning direction.

7. The light projecting and receiving apparatus described in claim 6 , wherein the light receiving system reflects the reflected light flux reflected from the object by a second mirror surface, further reflects the reflected light flux by a first mirror surface, and thereafter, receives the reflected light flux with the light receiving element.

8. The scanning optical system described in claim 2 , wherein the plurality of pairs of the first mirror surface and the second mirror surface includes a pair in which an intersection angle of the first mirror surface and the second mirror surface is 90 degrees.

Assignees

• Konica Minolta Inc

Inventors

• Ishikawa Ryouta
• Kogo Shoji

Classifications

• G02B27/0031

  for scanning purposes · CPC title

• G02B26/12

  using multifaceted mirrors · CPC title

• G02B26/129 Primary

  Systems in which the scanning light beam is repeatedly reflected from the polygonal mirror · CPC title

• G01S7/481

  Constructional features, e.g. arrangements of optical elements · CPC title

• G02B26/10

  Scanning systems · CPC title