FIBER UNIT

• US 20140177266A1
• Filed: 12/06/2013
• Published: 06/26/2014
• Est. Priority Date: 08/08/2012
• Status: Active Grant

• Current Assignee: Olympus Corporation
• Original Assignee: Olympus Medical Systems Corporation (Olympus Corporation)
• Inventors: KATAKURA, Masahiro, SUGA, Takeshi
• Granted Patent: US 9,014,517 B2
• Time in Patent Office: Days
• US Class Current: 362/574
• CPC Class Codes: A61B 1/00165 with light-conductive means, e.g. fibre optics A61B1/07 takes precedence
• CPC Class Codes: A61B 2562/0233 Special features of optical sensors or probes classified in A61B5/00
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: G02B 6/00 Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
• CPC Class Codes: G02B 6/02042 Multicore optical fibres

Abstract

A fiber unit has an illumination fiber and detection fibers. The illumination fiber and the detection fiber comprise a soft portion that is bendable, a distal end hard portion provided at an end thereof and having a greater hardness than the soft portion, and a pitch conversion portion that connects the soft portion and the distal end hard portion and changes a distance between adjacent fibers at the distal end hard portion with respect to a distance between the adjacent fibers at the soft portion, by bending and extending. 1.0 degree<Deg_max<6.0 degrees, where Deg_max is a most inclined angle of angles each formed by a central axis of the distal end hard portion and a line segment connecting an end portion of the pitch conversion portion closer to the soft portion and an end portion of the pitch conversion portion closer the distal end hard portion.

Claims

1. A fiber unit having one or a plurality of illumination fibers and a plurality of detection fibers and provided in a measurement probe that performs optical measurement by inputting and outputting light from a distal end thereof, wherein each of the illumination fibers and the detection fibers comprises:

a soft portion that is bendable;

a distal end hard portion provided at an end thereof and having a greater hardness than the soft portion; and

a pitch conversion portion that connects the soft portion and the distal end hard portion and changes a distance between adjacent fibers at the distal end hard portion with respect to a distance between the adjacent fibers at the soft portion, by bending and extending,

wherein when a most inclined angle of angles each formed by a central axis of the distal end hard portion and a line segment connecting an end portion of the pitch conversion portion closer to the soft portion and an end portion of the pitch conversion portion closer the distal end hard portion is denoted by Deg_max, the following is satisfied;

1.0 degree<

Deg_max<

6.0 degrees.

2. The fiber unit according to claim 1, further′

comprising a first covering unit that covers a lateral surface of the soft portion, wherein when a covering thickness of the first covering unit is denoted by D₁ and a length of the pitch conversion portion is denoted by D_A, the following is satisfied;

0.005<

D₁/D_A<

0.032.

3. The fiber unit according to claim 2, further comprising a second covering unit that covers lateral surfaces of the distal end hard portion and the pitch conversion portion, wherein when a covering thickness of the second covering unit is denoted by D₂, the following is satisfied:

15<

D₁/D₂<

100.

4. The fiber unit according to claim 1, wherein the illumination fibers and the detection fibers are arranged in a line.

5. The fiber unit according to claim 1, wherein each of the illumination fibers and the detection fibers includes a core unit that transmits light, wherein a diameter D_core of the core unit satisfies the following:

15 μ

m<

D_core<

45 μ

m.

6. The fiber unit according to claim 5, wherein each of the illumination fibers and the detection fibers comprises an outer layer unit covering an external periphery of the core unit and having a refractive index smaller than the core unit, wherein the diameter D_core of the core unit and the diameter D_clad of the outer layer unit satisfy the following:

0.60<

D_core/D_clad<

0.75,

and a numerical aperture NA of each of the illumination fibers and the detection fibers satisfies the following;

0.20<

NA<

0.25.