OPTICAL FIBER SCANNING APPARATUS AND ENDOSCOPE

• US 20190317316A1
• Filed: 06/25/2019
• Published: 10/17/2019
• Est. Priority Date: 12/26/2016
• Status: Active Grant

• Current Assignee: Olympus Corporation
• Original Assignee: Olympus Corporation
• Inventors: OGATA, Masanori
• Granted Patent: US 11,061,222 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 1/0008 characterised by distal tip features
• CPC Class Codes: A61B 1/00165 with light-conductive means, e.g. fibre optics A61B1/07 takes precedence
• CPC Class Codes: A61B 1/00172 with means for scanning
• CPC Class Codes: A61B 1/07 using light-conductive means, e.g. optical fibres
• CPC Class Codes: G02B 2006/0098 for scanning
• CPC Class Codes: G02B 23/2469 using optical fibres
• CPC Class Codes: G02B 26/103 having movable or deformable optical fibres, light guides or waveguides as scanning elements light guides per se G02B6/00
• CPC Class Codes: G02B 6/0006 Coupling light into the fibre in general G02B6/4298
• CPC Class Codes: G02B 6/0008 the light being emitted at the end of the fibre
• CPC Class Codes: H04N 23/555 for picking-up images in sites, inaccessible due to their dimensions or hazardous conditions, e.g. endoscopes or borescopes
• CPC Class Codes: H04N 23/56 provided with illuminating means

Abstract

An optical fiber scanning apparatus includes an optical fiber whose fixed end is fixed and a free end for emitting illumination light of which vibrates in a first direction (X-axis direction) and a second direction (Y-axis direction), a ferrule including a through hole through which the optical fiber is inserted and including a pair of first fixing sections and a pair of second fixing sections which respectively fix the fixed end of the optical fiber, and piezoelectric elements or a magnet configured to vibrate the optical fiber, in which the optical fiber is sandwiched between the pair of first fixing sections and fixed in the first direction, and is sandwiched between the pair of second fixing sections and fixed in the second direction, and the pair of first fixing sections and the pair of second fixing sections differ in a shape of an abutment portion abutting on the optical fiber.

Claims

1. An optical fiber scanning apparatus comprising:

an optical fiber a fixed end of which is fixed and a free end for emitting illumination light of which vibrates in a first direction and a second direction perpendicular to the first direction;

a ferrule including a through hole through which the optical fiber is inserted and including a pair of first fixing sections and a pair of second fixing sections which respectively fix the fixed end of the optical fiber; and

piezoelectric elements or a magnet configured to vibrate the optical fiber,

wherein the optical fiber is sandwiched between the pair of first fixing sections and fixed in the first direction, and is sandwiched between the pair of second fixing sections and fixed in the second direction, and the pair of first fixing sections and the pair of second fixing sections differ in a shape of an abutment portion abutting on the optical fiber.

2. The optical fiber scanning apparatus according to claim 1, wherein the pair of first fixing sections and the pair of second fixing sections are composed of a same material.

3. The optical fiber scanning apparatus according to claim 1, wherein a groove including an opening on a wall surface of the through hole and extending in the first direction is formed in each of the pair of second fixing sections.

4. The optical fiber scanning apparatus according to claim 3, wherein a width of the groove is a same as an outer diameter of the optical fiber, and the pair of second fixing sections do not prevent vibration in the first direction of the optical fiber.

5. The optical fiber scanning apparatus according to claim 3, wherein a width of the groove is less than an outer diameter of the optical fiber.

6. The optical fiber scanning apparatus according to claim 1, wherein at least one of the pair of first fixing sections and the pair of second fixing sections includes fixing sections respectively disposed in a pair of grooves facing each other among four grooves each including an opening on a wall surface of the through hole and formed to be rotationally symmetric around the through hole.

7. The optical fiber scanning apparatus according to claim 1, wherein each of the pair of first fixing sections and the pair of second fixing sections includes a fillet extending to an outer peripheral surface of the optical fiber from a distal end surface of the ferrule.

8. The optical fiber scanning apparatus according to claim 6, wherein the fixing section is composed of solder or resin.

9. The optical fiber scanning apparatus according to claim 6, wherein

a resonance frequency in the first direction of the optical fiber is lower than a resonance frequency in the second direction of the optical fiber, and

among corner portions formed between the distal end surface and side surfaces of the ferrule, corner portions in a direction in which the first fixing sections are disposed are chamfered.

10. An endoscope including an optical fiber scanning apparatus in a distal end portion of an insertion section,

the optical fiber scanning apparatus comprising

an optical fiber a fixed end of which is fixed and a free end for emitting illumination light of which vibrates in a first direction and a second direction perpendicular to the first direction,

a ferrule including a through hole through which the optical fiber is inserted and including a pair of first fixing sections and a pair of second fixing sections which respectively fix the fixed end of the optical fiber, and

piezoelectric elements or a magnet configured to vibrate the optical fiber,

wherein the optical fiber is sandwiched between the pair of first fixing sections and fixed in the first direction, and is sandwiched between the pair of second fixing sections and fixed in the second direction, and the pair of first fixing sections and the pair of second fixing sections differ in a shape of an abutment portion abutting on the optical fiber.

11. The endoscope according to claim 10, wherein

a movie with a frame rate of N (fps) is shot with reflected light from an object to be observed illuminated with the illumination light scanned by a Lissajous method, and

a difference between a resonance frequency in the first direction and a resonance frequency in the second direction of the optical fiber is kN (Hz) (k is a natural number).