Microlens array, optical apparatus, single lens reflex camera and optical finder

• US 20030002871A1
• Filed: 06/17/2002
• Published: 01/02/2003
• Est. Priority Date: 06/20/2001
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Ohmura, Yusuke
• Granted Patent: US 6,836,619 B2
• Time in Patent Office: Days
• US Class Current: 396/150
• CPC Class Codes: G02B 5/0221 the surface having an irregular structure G02B5/0226 takes precedence
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G03B 13/24 Focusing screens

Abstract

A microlens array described below is disclosed.

In the microlens array, a plurality of microlenses are formed with an irregularity or probability-distributed regularity so as to differ from a hypothetical base pattern, the hypothetical base pattern having apexes of hypothetical microlenses each spaced apart from every adjacent microlens thereof by an equal distance L. All the apex positions of the microlenses lie within circles each centered on an apex position in said hypothetical base pattern and having a radius equal to or smaller than 0.3L, or meet a condition: 0.4L≦P≦1.6L. In this way, a microlens array with bright and clean viewing characteristics and a high reproducibility of a shape of each microlens is provided.

Claims

1. A microlens array, comprising:

a plurality of microlenses formed with an irregularity or probability-distributed regularity so as to differ from a hypothetical base pattern, the hypothetical base pattern having apexes of hypothetical microlenses each spaced apart from every adjacent microlens thereof by an equal distance L,

wherein all the apex positions of the microlenses lie within circles each centered on an apex position in said hypothetical base pattern and having a radius equal to or smaller than 0.3L.

2. An optical apparatus, comprising:

the microlens array according to claim 1.

3. A single lens reflex camera, comprising:

a focusing screen constituted by the microlens array according to claim 1.

4. An optical finder, comprising:

a focusing screen constituted by the microlens array according to claim 1.

5. A microlens array, comprising:

a plurality of microlenses formed with an irregularity or probability-distributed regularity so as to differ from a hypothetical base pattern, the hypothetical base pattern having apexes of hypothetical microlenses each spaced apart from every adjacent microlens thereof by an equal distance L,

wherein an apex interval P between microlenses adjacent to each other meets the following condition;

0.4L≦

P≦

1.6L.

6. An optical apparatus, comprising:

the microlens array according to claim 5.

7. A single lens reflex camera, comprising:

a focusing screen constituted by the microlens array according to claim 5.

8. An optical finder, comprising:

a focusing screen constituted by the microlens array according to claim 5.