JP3199879U - High performance optical fiber cable - Google Patents

Abstract

A high-performance optical fiber cable that improves the reflectivity of an optical signal by a gap filled with air inside the optical fiber. A high-performance optical fiber cable includes a bellows tube, an optical fiber member, and two connectors. Each bellows tube has openings at both ends, and the optical fiber member is a bellows. An air gap is formed between the inside of the tube and the bellows tube, and a plurality of optical fibers are formed. The optical fiber member is installed at both ends of the optical fiber member, and attached to the outside of the corresponding opening of the bellows tube. [Selection] Figure 2

Description

  The present invention relates to a high-performance optical fiber cable that improves the reflectivity of an optical signal, particularly by a gap filled with air inside the optical fiber.

With the promotion of digital homes by electronic product manufacturers, the need for high-resolution audio and video continues to increase year by year, and video capture devices (monocular cameras, tape recorders, video recorders, etc.) and video processing devices (computers, cloud computing) Servers, etc.), video output devices (high-definition digital televisions) and other industries and consumer markets are expanding.
In addition, when using conventional cables when transmitting conventional analog signals, electromagnetic loss and absorption loss due to materials may occur, resulting in reduced energy and weakened signals. Cannot be displayed.

  For this reason, video related companies such as SONY and Philips developed an interface of S / PDIF (Sony / Philips Digital Interface Format) in the 1980s. According to this technical means, an analog signal can be converted into an optical signal, transmitted to a video terminal device via an optical fiber, and the optical signal can be converted into a digital signal by a decoder of the video terminal device. In other words, when an optical fiber is used, there is no problem such as electromagnetic loss, and absorption loss due to the material can be reduced, so that high-quality signal transmission can be provided for audio or video. This signal transmission technique is widely used in high-quality sound systems such as Digital Theater Systems (DTS) or Dolby Digital.

  As shown in FIG. 7, the conventional optical fiber cable has a single-core optical fiber 40, a clad 41, and a covering portion 42, and a clad 41 is provided on the outer peripheral surface of the single-core optical fiber 40. A covering portion 42 is provided on the outer peripheral surface of the clad 41, and both ends of the single-core optical fiber 40 are formed so as to protrude from the cladding 41 and the covering portion 42, respectively. When the single-core optical fiber 40 is used, one end is connected to a signal source, the other end is connected to a terminal device such as a video, and an analog signal from the signal source is converted into an optical signal to convert the single-core optical fiber. 40 to a terminal device such as a video. According to this configuration, since the optical signal inside the single-core optical fiber 40 is transmitted while being totally reflected, when the terminal device such as audio or video receives the signal, the optical signal is converted into a digital signal, and the signal is high. Resolution and high quality signals are obtained.

  However, the clad of the conventional optical fiber is usually made of polyethylene (PE, polyethylene) and has a refractive index of 1.52, but the difference between the two is small compared to the refractive index of 1.47 of the single-core optical fiber. . In this case, since the clad is perfectly coated on the surface of the single-core optical fiber by the optical Snell's Law (Shell's Law), the critical angle of total reflection is large, and the single-core optical fiber Since the ratio of total reflection of the internal optical signal is reduced and transmission loss is increased, a predetermined signal amount cannot be transmitted unless the inner diameter of the single-core optical fiber is increased. Therefore, the optical signal inside the conventional single-core optical fiber needs to pass through a long path, which has the disadvantage that the energy signal is attenuated and the optical signal deteriorates, so the structure needs to be improved. was there.

The high-performance optical fiber cable according to the present invention is
A bellows tube having openings at both ends, and
Light that penetrates inside the bellows tube, forms an air gap between the bellows tube, and includes a plurality of optical fibers, and both ends of each optical fiber project from openings at both ends of the bellows tube, respectively. A fiber member;
And two connectors that are installed at both ends of the optical fiber member and attached to the outside of the corresponding opening of the bellows tube.

In such a high performance optical fiber cable,
The connector includes an outer frame, an inner tube, a tip connecting unit, a spring, and a rear end connecting unit, and the outer frame is mounted around one end of an optical fiber member. The tube is attached to the outer frame, and the tip connecting unit, the spring, and the rear end connecting unit are sequentially attached to the optical fiber member and attached to the inner tube, and the spring is connected to the tip connecting unit. It is preferable to be sandwiched between the two while contacting the rear end connecting unit.

In such a high performance optical fiber cable,
The inner tube is inserted into the outer frame, a head protruding from the outer frame is provided at the tip, an insertion hole is formed in the head, and the tip connecting unit passes through the insertion hole and the inner tube It is preferable to protrude from the outside.

In such a high performance optical fiber cable,
It is preferable that a rubber ring is wrapped around the outer peripheral surface of the outer frame.

In such a high performance optical fiber cable,
The optical fiber member preferably includes at least 7000 optical fibers.

In such a high performance optical fiber cable,
The bellows tube is preferably configured by spirally winding a long metal material.

In such a high performance optical fiber cable,
It is preferable that a covering member formed by knitting a plastic material is provided outside the bellows tube.

  The high-performance optical fiber cable according to the present invention mainly increases the ratio of performing total reflection of the optical fiber using the refractive index of air by forming an air gap between the optical fiber member and the bellows tube, In addition, since the optical fiber member is composed of a plurality of small-diameter optical fibers, the signal transmission path is shortened to increase the optical signal transmission effect, so that the weakening of the optical signal is reduced and the high-performance signal is reduced. Can achieve transmission.

1 is a perspective view of a high performance optical fiber cable according to the present invention. 1 is an exploded perspective view of a high performance optical fiber cable according to the present invention. 1 is a partial cross-sectional view of a high performance optical fiber cable according to the present invention. 1 is a side sectional view of a high-performance optical fiber cable according to the present invention. 1 is a partially enlarged cross-sectional view of a high performance optical fiber cable according to the present invention when viewed from the front. It is explanatory drawing which shows the optical total reflection state in the high performance optical fiber cable which concerns on this invention. It is a side view fragmentary sectional view of the conventional optical fiber cable.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, the following Example is only what showed the preferred embodiment of this invention, and the technical scope of this invention is not limited to the following Example itself at all.

As shown in FIGS. 1 to 3, the high-performance optical fiber cable according to the present invention includes a bellows tube 10, an optical fiber member 20, and two connectors 30.
Among them, openings are formed at both ends of the bellows tube 10, the outer diameter of the optical fiber member 20 is smaller than the inner diameter of the bellows tube 10, and the optical fiber member 20 is coaxially provided inside the bellows tube 10. The
Furthermore, the bellows tube 10 is formed by spirally winding a long metal material, and has elasticity and flexibility. If the metal bellows tube 10 is provided, the optical fiber member 20 inside the metal bellows tube 10 can be protected, and external pressure or impact can be prevented. Further, a covering member 100 configured by weaving a plastic material such as nylon outside the bellows tube 10 is provided.

Since the optical fiber member 20 is coaxially provided inside the bellows tube 10 and the outer diameter of the optical fiber member 20 is smaller than the inner diameter of the bellows tube 10, the optical fiber member 20 An air gap 11 is formed between the bellows tube 10 and the air gap 11 is filled with normal air, so that the outer circumference of the optical fiber member 20 is not completely covered with the bellows tube 10.
The optical fiber member 20 is composed of a plurality of optical fibers 21, and the optical fibers 21 are arranged in the lateral direction, and both ends of the optical fibers 21 protrude from the openings at both ends of the bellows tube 10. .
The optical fiber member 20 of the present embodiment is made of an optical fiber material at the same level as that of an industrial optical fiber endoscope, and includes at least 7000 optical fibers 21. Communication can be performed at a resolution higher than a pixel.

  An optical signal input connector 30 is installed at one end of the optical fiber member 20 and an optical signal output connector 30 is installed at the other end. Each connector 30 corresponds to the bellows tube 10. Installed outside the opening. In this embodiment, each connector 30 has an outer frame 31, a rubber ring 32, an inner tube 33, a tip connecting unit 34, a spring 35, and a rear end connecting unit 36. Among them, the outer frame 31 is mounted on one end of the optical fiber member 20, the rubber ring 32 is mounted on the outer peripheral surface of the outer frame 31, and the inner tube body 33 is connected to the optical fiber in the outer frame 31. It is attached so as to be inserted from the end opposite to the member 20, and a head 331 is provided at the tip of the inner tube 33 so as to protrude from the outer frame 31, and an insertion hole 332 is formed in the head 331. The front end connecting unit 34, the spring 35, and the rear end connecting unit 36 are sequentially attached to the optical fiber member 20 and attached to the head 331 of the inner tube 33. The front end connecting unit 34 passes through the insertion hole 332. From the inner tube 33 Protrudes into parts, the spring 35 is sandwiched between them while in contact with the distal end connecting unit 34 and the rear end connecting unit 36.

  When using the high-performance optical fiber cable according to the present invention, the connector 30 at one end is connected to the optical signal output end, the connector 30 at the other end is connected to the optical signal input end, and the optical signal is output from the optical signal output end. Is transmitted from the optical fiber member 20 to the optical signal input end, so that the optical signal inside the optical fiber member 20 can be transmitted while being totally reflected.

As shown in FIGS. 2 to 5, an air gap 11 is formed between the optical fiber member 20 and the bellows tube 10, and the air gap 11 is filled with air, so that the optical signal is totally reflected. Therefore, the absorption loss due to the signal material can be greatly reduced. When a part of the optical signal enters one of the plurality of optical fibers 21, the optical signal is transmitted while being totally reflected by the inner wall of the optical fiber 21.
In addition, the total reflection is related to the refractive index of the interface of different materials and the incident angle of the optical signal from the signal input source, that is, based on the wave-particle duality of quantum physics. Thus, a part of the optical signal input to the optical fiber 21 is defined as a photon (Photon), and the two materials in the photon are defined according to Snell's Law well known to those skilled in the optical field. The critical angle for realizing total reflection at the interface with different refractive index is calculated.
As shown in FIG. 6, an appropriate critical angle when the photon enters the interface of refractive index n ₂ from the interface of refractive index n ₁ can be calculated by the following formula.
θc = arcsin (n ₁ / n ₂ )

With respect to the above-mentioned interfaces having different materials and refractive indexes, the photon is obtained under the condition that the refractive index n ₁ is larger than the refractive index n ₂ and the angle between the incident locus of the photon and the normal of the interface is larger than the critical angle θc. Total reflection can be achieved.
Also, if the photon satisfies the conditions for realizing total internal reflection, the photon two materials are then transmitted to a different interface, not divided polarization components to the interface of refractive index n _2, the refractive index n ₁ Total reflection on the interface.
Therefore, the loss of photon energy is extremely small, and even if an optical signal is transmitted from one end of the optical fiber member 20 to the other end, it is not attenuated and deteriorated.
Further, according to the above formula, the greater the difference between the refractive index n ₁ and the refractive index n ₂ , the smaller the critical angle θc at which total reflection is possible, that is, the greater the difference in refractive index. The achievement rate of total reflection increases and the loss of light energy also decreases.

In this embodiment, the refractive index of the optical fiber 21 is 1.47, the refractive index of air (1 atm, 0 ° C.) is 1.0, and the conventional single-core optical fiber is made of polyethylene. The refractive index is 1.52, and by subtraction, if the refractive index of air is subtracted from the refractive index of 1.47 of the optical fiber 21, it becomes 0.47, and the refractive index of the optical fiber 21 is 1.47. If the refractive index 1.52 of the cladding is subtracted to 0.05, the difference in refractive index between the optical fiber 21 and air is larger than the difference between the optical fiber 21 and the conventional cladding. The critical angle θc at which the total reflection 21 realizes total reflection is smaller than that of the conventional optical fiber, so that the ratio of achieving total reflection can be increased and energy loss can be reduced.
As described above, the high-performance optical fiber cable according to the present invention has the air gap 11 formed between the optical fiber member 20 and the bellows tube 10, so that the entire optical fiber is utilized by utilizing the refractive index of air. The ratio for realizing the reflection is increased, the optical signal transmission effect is increased, the deterioration due to attenuation of the optical signal is reduced, and high-performance signal transmission is performed.

  Further, the optical fiber member 20 is composed of a plurality of optical fibers 21, and each optical fiber 21 has a small diameter, so that the transmission path of the optical signal is shortened and a predetermined amount of optical signal can be transmitted. Therefore, the optical signal is not attenuated and deteriorated due to absorption loss caused by the material.

DESCRIPTION OF SYMBOLS 10 Bellows tube 11 Air gap 20 Optical fiber member 21 Optical fiber 30 Connector 31 Outer frame 32 Rubber ring 33 Inner tube 331 Head 332 Insertion hole 34 End connection unit 35 Spring 36 Rear end connection unit 100 Cover member 40 Core optical fiber 41 Cladding 42 Covering part

Claims (7)

A bellows tube having openings at both ends, and
Light that penetrates inside the bellows tube, forms an air gap between the bellows tube, and includes a plurality of optical fibers, and both ends of each optical fiber project from openings at both ends of the bellows tube, respectively. A fiber member;
A high-performance optical fiber cable having two connectors respectively installed at both ends of the optical fiber member and attached to the outside of the corresponding opening of the bellows tube.   The connector includes an outer frame, an inner tube, a tip connecting unit, a spring, and a rear end connecting unit, and the outer frame is mounted around one end of an optical fiber member. The tube is attached to the outer frame, and the tip connecting unit, the spring, and the rear end connecting unit are sequentially attached to the optical fiber member and attached to the inner tube, and the spring is connected to the tip connecting unit. The high-performance optical fiber cable according to claim 1, wherein the high-performance optical fiber cable is sandwiched between the two while being in contact with the rear end connecting unit.   The inner tube is inserted into the outer frame, a head protruding from the outer frame is provided at the tip, an insertion hole is formed in the head, and the tip connecting unit passes through the insertion hole and the inner tube The high-performance optical fiber cable according to claim 2, wherein the high-performance optical fiber cable protrudes outward from the cable.   4. The high-performance optical fiber cable according to claim 3, wherein a rubber ring is wrapped around the outer peripheral surface of the outer frame.   The high-performance optical fiber cable according to any one of claims 1 to 4, wherein the optical fiber member includes at least 7000 optical fibers.   The high-performance optical fiber cable according to claim 5, wherein the bellows tube is configured by spirally winding a long metal material.   6. The high-performance optical fiber cable according to claim 5, wherein a covering member formed by knitting a plastic material is provided outside the bellows tube.

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