Endoscopic system using an extremely fine composite optical fiber

An endoscopic system, comprising:

• a composite optical fiber consisting essentially of
• a large-diameter, laser light transmitting optical fiber and
• a large number of image transmitting fibers that are bundled together to form an integral assembly with a central fiber,
• the large-diameter optical fiber being surrounded by the image transmitting fibers and
• the image transmitting optical fibers being fused to form a monolithic sea-island structure in which a large number of cores as islands are surrounded by a continuous phase of a cladding as a sea;
• a laser treatment and image observing optical unit that is connected to an eyepiece portion of said composite optical fiber such that the unit launches laser light into said large-diameter optical fiber and such that an image being transmitted through said image transmitting optical fiber is focused on a camera to become observable, and
• an illuminating light transmitting unit that transmits illuminating light to a tip of an objective portion of said composite optical fiber for irradiation purposes,
• wherein said laser treatment and image observing optical unit includes a beam splitter that reflects an emission of laser light from a laser oscillator to be launched into said large-diameter, laser light transmitting optical fiber and that transmits an image traveling through said image transmitting optical fiber so that it is focused on said camera,
• said illuminating light transmitting unit includes a light source and a light guide fiber that transmits the illuminating light emerging from said light source, at least a tip portion of said light guide fiber being made integral with said image transmitting optical fibers in its longitudinal direction, and
• said light guide fiber is made of a multi-component glass suitable for irradiating a wide range and is provided along the composite optical fiber, and
• wherein said large-diameter, laser light transmitting optical fiber and said image transmitting optical fibers are each an optical fiber having a core/cladding index difference Δ is 3.5 to 4%.

An endoscopic system, comprising:

• a composite optical fiber consisting essentially of
• a large-diameter, laser light transmitting optical fiber and
• a large number of image transmitting fibers that are bundled together to form an integral assembly with a central fiber,
• the large-diameter optical fiber being surrounded by the image transmitting fibers;
• a laser treatment and image observing optical unit that is connected to an eyepiece portion of said composite optical fiber such that the unit launches laser light into said large-diameter optical fiber and such that an image being transmitted through said image transmitting optical fiber is focused on a camera to become observable, and
• an illuminating light transmitting unit that transmits illuminating light to a tip of an objective portion of said composite optical fiber for irradiation purposes,
• wherein said laser treatment and image observing optical unit includes a beam splitter that reflects an emission of laser light from a laser oscillator to be launched into said large-diameter, laser light transmitting optical fiber and that transmits an image traveling through said image transmitting optical fiber so that it is focused on said camera,
• the image transmitting optical fibers are fused to form a monolithic sea-island structure in which a large number of cores as islands are surrounded by a continuous phase of a cladding as a sea,
• said illuminating light transmitting unit includes a light source and a light guide fiber that transmits the illuminating light emerging from said light source, at least a tip portion of said light guide fiber being made integral with said image transmitting optical fibers in its longitudinal direction;
• said light guide fiber is made of a multi-component glass suitable for irradiating a wide range and is provided along the composite optical fiber, and
• wherein said large-diameter, laser light transmitting optical fiber and said image transmitting optical fibers are each an optical fiber having a core/cladding index difference Δ is 3.5 to 4%.

An endoscopic system, comprising:

• a composite optical fiber consisting essentially of
• a large-diameter, laser light transmitting optical fiber and
• a large number of image transmitting fibers that are bundled together to form an integral assembly with a central fiber, the large-diameter optical fiber being surrounded by the image transmitting fibers;
• a laser treatment and image observing optical unit that is connected to an eyepiece portion of said composite optical fiber such that the unit launches laser light into said large-diameter optical fiber and such that an image being transmitted through said image transmitting optical fiber is focused on a camera to become observable, and
• an illuminating light transmitting unit that transmits illuminating light to a tip of an objective portion of said composite optical fiber for irradiation purposes, wherein
• the large-diameter, laser light transmitting optical fiber comprises a core made of a GeO2 doped quartz glass and a cladding made a quartz glass, a diameter of the core is in the range of 50 to 400 μm whereas a diameter of the cladding ranges from 1.02 to 1.3 times the core diameter, and the cladding of the large-diameter, laser light transmitting optical fiber has a lower reflective index that that of the core of the optical fiber, a value of a core/cladding difference Δ being between 3.5 to 4%;
• the image transmitting optical fibers are fused to form a monolithic sea-Island structure in which a large number of cores as islands are surrounded by a continuous phase of a cladding as a sea, the cores are made of a GeO2 doped quartz glass, the cladding is made of pure quartz glass or a fluorine doped quartz glass, and a value of a core/cladding index difference Δ is adjusted between 3.5 to 4%. to reduce a core-to-core spacing to as small as 3 μm;
• and
• the illuminating a light transmitting unit comprises a light source and a light guide fiber which consists of a multi-component glass suitable for irradiating a wide range of area and an angle of viewing of 60 to 120° and is provided along the composite optical fiber.

An endoscopic system, comprising:

• a composite optical fiber consisting essentially of
• a large-diameter center fiber transmitting laser light, and
• image transmitting optical fibers surrounding the large-diameter center fiber,
• the image transmitting fibers being bundled together to form an integral assembly with the large-diameter center fiber, being fused to form a monolithic sea-island structure in which a large number of cores as islands are surrounded by a continuous phase of cladding as a sea,
• a first portion of said image transmitting optical fibers being used for irradiation purposes and
• a second portion of said image transmitting optical being used for observing a blood flow;
• a laser treatment and image observing optical unit that is connected to an eyepiece portion of said composite optical fiber, to input laser light into said large-diameter center fiber, and to observe an image received through said second portion of the image transmitting optical fibers focused on a camera;
• and
• an illuminating light transmitting unit that transmits illuminating light to a tip of an objective portion of the composite optical fiber for irradiation purposes,
• wherein said illuminating light transmitting unit includes a light source and a light guide optical fiber that transmits the illuminating light emerging from said light source to the first portion of said image transmitting optical fibers used for irradiation purposes.

An endoscopic system, comprising:

• a composite optical fiber consisting essentially of
• a large-diameter center fiber transmitting laser light, and
• image transmitting optical fibers surrounding the large-diameter center fiber,
• the image transmitting fibers being bundled together to form an integral assembly with the large-diameter center fiber, being fused to form a monolithic sea-island structure in which a large number of cores as islands are surrounded by a continuous phase of cladding as a sea,
• a first portion of said image transmitting optical fibers being used for irradiation purposes and
• a second portion of said image transmitting optical fibers being used for observing a blood flow;
• a laser treatment and image observing optical unit that is connected to an eyepiece portion of said composite optical fiber, to input laser light into said large-diameter center fiber, and to observe an image received through said second portion of the image transmitting optical fibers focused on a camera;
• and
• an illuminating light transmitting unit that transmits illuminating light to a tip of an objective portion of the composite optical fiber,
• wherein
• said laser treatment and image observing optical unit includes a beam splitter that directs laser light emitted by a laser oscillator into said large-diameter center fiber and transmits the image received through said second portion of image transmitting optical fibers to be focused on said camera,
• said illuminating light transmitting unit includes a light source and a light guide optical fiber that transmits the illuminating light emerging from said light source to the first portion of said image transmitting optical fibers used for irradiation purposes, and
• said light guide optical fiber is made of a multi-component glass suitable for illuminating a wide range of area and is provided along the composite optical fiber.

An endoscopic system, comprising:

• a composite optical fiber consisting essentially of
• a large-diameter center fiber transmitting laser light, and
• image transmitting optical fibers surrounding the large-diameter center fiber,
• the image transmitting fibers being bundled together to form an integral assembly with the large-diameter center fiber,
• a first portion of said image transmitting optical fibers being used for irradiation purposes and
• a second portion of said image transmitting optical fibers being used for observing a blood flow;
• a laser treatment and image observing optical unit that is connected to an eyepiece portion of said composite optical fiber, to input laser light into said large-diameter center fiber, and to observe an image received through said second portion of the image transmitting optical fibers focused on a camera;
• and
• an illuminating light transmitting unit that transmits illuminating light to a tip of an objective portion of the composite optical fiber,
• wherein
• said laser treatment and image observing optical unit includes a beam splitter that directs laser light emitted by a laser oscillator into said large-diameter center fiber and transmits the image received through said second portion of image transmitting optical fibers to be focused on said camera,
• said image transmitting optical fibers are fused to form a monolithic sea-island structure in which cores are as islands surrounded by a continuous phase cladding as a sea, and
• said illuminating light transmitting unit includes a light source and a light guide optical fiber that transmits the illuminating light emerging from said light source to the first portion of said image transmitting optical fibers, said light guide optical fiber being connected to the first portion of the image transmitting optical fibers used for irradiation purposes, and
• said light guide optical fiber is made of a multi-component glass suitable for illuminating a wide range and is provided along the composite optical fiber.

An endoscopic system, comprising:

• a composite optical fiber consisting essentially of
• a large-diameter center fiber transmitting laser light, and
• image transmitting optical fibers surrounding the large-diameter center fiber,
• the image transmitting fibers being bundled together to form an integral assembly with the large-diameter center fiber,
• a first portion of said image transmitting optical fibers being used for irradiation and
• a second portion of said image transmitting optical fibers being used for observing a blood flow;
• a laser treatment and image observing optical unit that is connected to an eyepiece portion of said composite optical fiber, to input laser light into said large-diameter center fiber, and to observe an image received through said second portion of the image transmitting optical fibers focused on a camera;
• and
• an illuminating light transmitting unit that transmits illuminating light to a tip of an objective portion of the composite optical fiber,
• wherein
• said large-diameter center fiber has a core made of GeO2 doped quartz glass and a cladding made of quartz glass, a diameter of the core being between 50 and 400 μm and a diameter of the cladding being 1.02 to 1.03 times the diameter of the core, the cladding of the large-diameter center fiber having a reflective index lower than a reflective index of the core of the large-diameter center fiber,
• the image transmitting optical fibers are fused to form a monolithic sea-island structure in which cores are as islands surrounded by a continuous phase cladding as a sea, the cores of the image transmitting optical fibers being made of GeO2 doped quartz glass, and the continuous phase cladding being made of pure glass or a fluorine doped quartz glass, which a core/cladding index difference Δ being 2 to 5%, a core-to-core spacing being down to 3 μm, and
• said illuminating light transmitting unit includes a light source and a light guide optical fiber which consists of a multi-component glass suitable for illuminating a wide range of area and an angle of viewing of 60 to 120°, said light guide optical fiber being connected to the first portion of the image transmitting optical fibers used for irradiation.