Illumination apparatus and image pickup apparatus

• US 8,147,078 B2
• Filed: 09/04/2009
• Issued: 04/03/2012
• Est. Priority Date: 09/10/2008
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Idera, Shuichi
• Primary Examiner(s): Neils, Peggy A.
• Application Number:
  US12/554,496
• Publication Number:
  US 20100061102A1
• Time in Patent Office: 942 Days
• Field of Search: 362/3, 362/16, 362/309, 362/310, 362/328, 362/329, 396/176, 396/200, 348/371
• US Class Current: 362/16
• CPC Class Codes: G03B 15/05 Combinations of cameras with electronic flash apparatus; Electronic flash units
• CPC Class Codes: G03B 2215/0503 Built-in units
• CPC Class Codes: G03B 2215/0578 Flashtube mounting
• CPC Class Codes: G03B 2215/0592 installed in front of light emitter

Abstract

The illumination apparatus includes a light source, an optical member configured to at least transmit therethrough light from the light source, and a reflective member configured to include a reflective portion which extends closer to the optical member than the light source and reflects the light from the light source to cause the light to enter the optical member. A concave portion is formed, on a light entrance side surface of the optical member, in an outside area located outside a light entrance area where the light reflected by the reflective portion reaches. The concave portion includes a refractive surface refracting light, which is part of the light from the light source and enters the concave portion without being reflected by the reflective portion, toward an exit surface of the optical member.

Claims

1. An illumination apparatus comprising:

a light source;

an optical member configured to at least transmit therethrough light from the light source; and

a reflective member configured to include a reflective portion which extends closer to the optical member than the light source and reflects the light from the light source to cause the light to enter the optical member,

wherein an upper inner surface of the optical member and a lower inner surface of the optical member disposed between a light entrance surface of the optical member and an exit surface of the optical member are formed as internal reflective surfaces,

wherein a concave portion is formed in upper and lower outside areas located outside the light entrance surface where the light reflected by the reflective portion reaches,

wherein the concave portion includes a refractive surface refracting light, and

wherein the refractive surface reflects light proceeding toward the refractive surface from the light entrance surface of the optical member, and the reflected light introduces to the exit surface of the optical member.

2. The illumination apparatus according to claim 1,

wherein the reflective member is configured to include as the reflective portion a first reflective portion and a second reflective portion each of which extends closer to the optical member than the light source and reflects the light from the light source to cause the light to enter the optical member, and

wherein the concave portion includes a first concave portion and a second concave portion,

wherein the first concave portion is concaved so as to be away from front end of the first reflective portion, and

wherein the second concave portion is concaved so as to be away from front end of the second reflective portion.

3. An image pickup apparatus capturing an image of an object illuminated with light from an illumination apparatus, the image pickup apparatus comprising:

the illumination apparatus which comprises;

a light source;

an optical member configured to at least transmit therethrough light from the light source; and

a reflective member configured to include a reflective portion which extends closer to the optical member than the light source and reflects the light from the light source to cause the light to enter the optical member,

wherein an upper inner surface of the optical member and a lower inner surface of the optical member disposed between a light entrance surface of the optical member and an exit surface of the optical member are formed as internal reflective surfaces,

wherein a concave portion is formed in upper and lower outside areas located outside the light entrance surface where the light reflected by the reflective portion reaches,

wherein the concave portion includes a refractive surface refracting light, and

wherein the refractive surface reflects light proceeding toward the refractive surface from the light entrance surface of the optical member, and the reflected light introduces to the exit surface of the optical member.