Optical apparatus, image forming apparatus, and image reading apparatus

Patent metadata

Field	Value
Publication number	US-9541756-B2
Application number	US-201314655082-A
Country	US
Kind code	B2
Filing date	Dec 18, 2013
Priority date	Dec 27, 2012
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

An optical apparatus includes: a light source including multiple light-emitting points arrayed in a first direction; and an imaging optical system including multiple lens optical systems arrayed in the first direction. The imaging optical system forms images of the multiple light-emitting points on a light-receiving surface. In a first cross-section and in a second cross-section, half-value of a maximum value of angle of divergence of an imaging optical flux input to the light-receiving surface, resolution, and a size of each image of the plurality of light-emitting points formed on the light-receiving surface, satisfy predetermined conditions.

First claim

The invention claimed is:

1. An optical apparatus comprising:
a light source including a plurality of light-emitting points arrayed in a first direction; and
an imaging optical system including a plurality of lens optical systems arrayed in the first direction wherein the imaging optical system forms images of the plurality of light-emitting points on a light-receiving surface; and
wherein a condition of

0.8
≤

P
m

P
s

⁢

1
-

P
s

⁢

D
s

1
-

P
m

⁢

D
m

⁢

tan
⁢

⁢

θ
m

tan
⁢

⁢

θ
s

≤
1.2

is satisfied, where
in a first cross-section which is parallel to the first direction and an axial direction of the lens optical systems, θ m represents a half-value of a maximum value of angle of divergence of an imaging optical flux input to the light-receiving surface, P m [lp/mm] represents resolution, and D m [mm] represents a size of each image of the plurality of light-emitting points, formed on the light-receiving surface, and
in a second cross-section which is perpendicular to the first direction, θ s represents a half-value of a maximum value of angle of divergence of an imaging optical flux input to the light-receiving surface, P s [lp/mm] represents resolution, and D s [mm] represents a size of each image of the plurality of light-emitting points, formed on the light-receiving surface.

2. The optical apparatus according to claim 1 , wherein θ m is θ m ′ which is half-value of a maximum value of effective angle of divergence, and θ s is θ s ′ which is half-value of a maximum value of effective angle of divergence.

3. The optical apparatus according to claim 1 , wherein the imaging optical system performs erecting same-size imaging of each of the plurality of light-emitting points on the light-receiving surface in the first cross-section, and performs inverted imaging of each of the plurality of light-emitting points on the light-receiving surface in the second cross-section.

4. The optical apparatus according to claim 1 , wherein the plurality of lens optical systems each have an anamorphic surface.

5. The optical apparatus according to claim 1 , wherein the plurality of lens optical systems each include a plurality of lens portions arrayed in the optical axis direction of the lens optical systems.

6. The optical apparatus according to claim 1 , wherein the imaging optical system is an enlarging system in the second cross-section.

7. The optical apparatus according to claim 1 , wherein the plurality of light-emitting points are organic light-emitting devices.

8. An optical apparatus comprising:
a light source including a plurality of light-emitting points arrayed in a first direction; and
an imaging optical system including a plurality of lens optical systems arrayed in the first direction,
wherein the imaging optical system forms images of the plurality of light-emitting points on a light-receiving surface, and
wherein a condition of

0.8
≤

P
m

P
s

⁢

1
-

P
s

⁢

D
s

1
-

P
m

⁢

D
m

⁢

n
m

⁢
P

T

≤
1.2

is satisfied, where
in a first cross-section which is parallel to the first direction and an axial direction of the lens optical systems, p [mm] represents an array pitch of the plurality of lens optical systems, n m represents the maximum number of lens optical systems through which light rays from one of the plurality of light-emitting points pass, P m [lp/mm] represents resolution, and D m [mm] represents a size of each image of the plurality of light-emitting points, formed on the light-receiving surface, and
in a second cross-section which is perpendicular to the first direction, T [mm] represents the maximum effective width of the imaging optical system, P s [lp/mm] represents resolution, and D s [mm] represents a size of each image of the plurality of light-emitting points, formed on the light-receiving surface.

9. The optical apparatus according to claim 8 , wherein the maximum number n m is the maximum effective number n m ′.

10. The optical apparatus according to claim 8 , satisfying a condition of
n m ≦4.

11. The optical apparatus according to claim 8 , wherein the imaging optical system performs erecting same-size imaging of each of the plurality of light-emitting points on the light-receiving surface in the first cross-section, and performs inverted imaging of each of the plurality of light-emitting points on the light-receiving surface in the second cross-section.

12. The optical apparatus according to claim 8 , wherein the plurality of lens optical systems each have an anamorphic surface.

13. The optical apparatus according to claim

Assignees

• Canon Kk

Inventors

• Saiga Takeyoshi
• Teramura Masayasu
• Miyajima Yu

Classifications

• H04N1/02409

  Focusing, i.e. adjusting the focus of the scanning head · CPC title

• G02B27/0018

  with means for preventing ghost images (anti-reflection coatings G02B1/11) · CPC title

• G02B13/26 Primary

  for reproducing with unit magnification · CPC title

• G02B3/005

  arranged along a single direction only, e.g. lenticular sheets (G02B3/0043 takes precedence) · CPC title

• G03G15/0435

  by introducing an optical element in the optical path, e.g. a filter · CPC title