GB2076988A - Infra red transmitting light guide - Google Patents
Infra red transmitting light guide Download PDFInfo
- Publication number
- GB2076988A GB2076988A GB8114107A GB8114107A GB2076988A GB 2076988 A GB2076988 A GB 2076988A GB 8114107 A GB8114107 A GB 8114107A GB 8114107 A GB8114107 A GB 8114107A GB 2076988 A GB2076988 A GB 2076988A
- Authority
- GB
- United Kingdom
- Prior art keywords
- transmission path
- infrared light
- light transmission
- fibers
- light guide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- -1 silver halide Chemical class 0.000 claims abstract description 20
- 229910052709 silver Inorganic materials 0.000 claims abstract description 11
- 239000004332 silver Substances 0.000 claims abstract description 11
- 229910052716 thallium Inorganic materials 0.000 claims abstract description 10
- 239000004033 plastic Substances 0.000 claims abstract description 6
- 229920003023 plastic Polymers 0.000 claims abstract description 6
- 230000005855 radiation Effects 0.000 claims abstract description 6
- 239000000835 fiber Substances 0.000 claims description 28
- 230000005540 biological transmission Effects 0.000 claims description 23
- 239000013078 crystal Substances 0.000 claims description 18
- 238000000576 coating method Methods 0.000 claims description 7
- 239000011248 coating agent Substances 0.000 claims description 6
- 230000001419 dependent effect Effects 0.000 claims 1
- 238000009529 body temperature measurement Methods 0.000 abstract description 3
- 230000003287 optical effect Effects 0.000 description 7
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 3
- 229910021607 Silver chloride Inorganic materials 0.000 description 3
- 150000004820 halides Chemical class 0.000 description 3
- 238000002329 infrared spectrum Methods 0.000 description 3
- ADZWSOLPGZMUMY-UHFFFAOYSA-M silver bromide Chemical group [Ag]Br ADZWSOLPGZMUMY-UHFFFAOYSA-M 0.000 description 3
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 3
- 238000005253 cladding Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- CPELXLSAUQHCOX-UHFFFAOYSA-M Bromide Chemical compound [Br-] CPELXLSAUQHCOX-UHFFFAOYSA-M 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 1
- 229910018557 Si O Inorganic materials 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 229920001903 high density polyethylene Polymers 0.000 description 1
- 239000004700 high-density polyethylene Substances 0.000 description 1
- 238000001192 hot extrusion Methods 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- XMBWDFGMSWQBCA-UHFFFAOYSA-N hydrogen iodide Chemical compound I XMBWDFGMSWQBCA-UHFFFAOYSA-N 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000013307 optical fiber Substances 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Inorganic materials [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 1
- 238000004611 spectroscopical analysis Methods 0.000 description 1
- 238000002834 transmittance Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/44—Mechanical structures for providing tensile strength and external protection for fibres, e.g. optical transmission cables
- G02B6/4401—Optical cables
- G02B6/4403—Optical cables with ribbon structure
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/02—Constructional details
- G01J5/08—Optical arrangements
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/02—Constructional details
- G01J5/08—Optical arrangements
- G01J5/0818—Waveguides
- G01J5/0821—Optical fibres
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
- G02B6/102—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type for infrared and ultraviolet radiation
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Optics & Photonics (AREA)
- Health & Medical Sciences (AREA)
- Toxicology (AREA)
- Radiation Pyrometers (AREA)
- Measuring Temperature Or Quantity Of Heat (AREA)
- Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
Abstract
The light guide comprises an assembly of fibres 3 of crystalline silver halide or thallium halide and a flexible sheath 4, 5 of rubber or plastics. The fibres may be of circular or rectangular section. The assembly of fibres may be of circular or (as shown) flattened section. For temperature measurement, infra red radiation from the object is focussed onto the guide which directs it to one or more radiation detectors. If the light guide is flattened in section, and the fibres are connected to respective detectors, the position or movement of the object can be detected. <IMAGE>
Description
SPECIFICATION
An infrared light transmission path
This invention relates to an infrared light transmission path.
Objects radiate infrared rays whose energy varies with their temperature. The relation between the wavelength for the peak of the magnitude of the radiation and the temperature of the object is represented by formula (1) that is derived from Planck's law of radiation: Am.T=. K (1) wherein Am is the wavelength (lim) at which a maximum intensity of light is radiated, T is the absolute temperature ("K) of the object, and K is a constant (K = 2897 ym.deg). This formula indicates that the temperature of an object can be measured by detecting its infrared spectrum.
A wide range of temperatures can be determined by infrared light transmitting fibers made of a silver halide or thallium halide crystal that transmits light in the far infrared spectrum of from 0.5 to 1 5 microns and from which is easy to produce polycrystalline fibers by hot working. An optical temperature measurement generally involves the guiding of light from a remote or inaccessible source to an infrared spectrum detecting optical system by means of a lens, prism or reflective mirror.
This method requires much time in adjusting the optical axis precisely and, to maintain the optical accuracy, the equipment must be installed in a place where dust does not build up on the lens or reflective mirror and where minimum vibration occurs.
A system is known that transmits light from the source to the light detector over a desired path of quartz glass fibers that are used as optical fibers for communication. The formula (1) indicates that the light radiated from an object having a temperature of 773"K (500"C) has a peak wavelength at about 3.8 microns, and it shifts to a longer wavelength if the temperature of the object is decreased.
Therefore, the system of using quartz glass is unsuitable for measuring the temperature of cold objects; quartz glass has a great absorption loss at about 4.75 mcrons due to the vibration of the lattice of Si-O bond and this affects the transmission of infrared light.
Therefore, an object of this invention is to eliminate or minimise the above-mentioned problems experienced in the prior art and provide an infrared light transmission path that transmits a wide spectrum of light and hence can measure a wide range of temperatures.
Accordingly, the invention resides in an infrared light transmission path for transmitting heat rays which comprises a plurality of fibers of a silver halide crystal, a mixed crystal of silver halide, a thallium halide crystal or a mixed crystal of thallium halide, said fibers being encased in a rubber or plastic flexible coating.
In the accompanying drawings,
Figures 1 and 2 are illustrations of two types of fiber which can be used in the infrared light transmission path of this invention;
Figures 3 and 4 are perspective views of infrared light transmission paths according to first and second examples respective of the invention, and
Figure 5 is a block diagram of a temperature measurement system using the infrared light transmission path of Fig. 3 or Fig. 4.
Referring to the drawings, Fig. 1 depicts a fiber having a circular cross section produced by hot extrusion, and Fig. 2 depicts a fiber having a rectangular cross section produced by hot rolling. Each fiber is of the step index type wherein the core 1 has a higher refractive index than the cladding 2 to confine light rays in the core. Alternatively, the fiber may be of graded index type wherein the refractive index decreases from the center outwards.
Fig. 3 illustrates an infrared light transmission path comprising a bundle of fibers encased in a large-diameter cylindrical plastic tube, whereas Fig. 4 illustrates an infrared light transmission path comprising a row of fibers encased in a flat plastic tube. In Figs. 3 and 4 the reference numeral 3 depicts an individual fiber, the numeral 4 is a primary coating, and 5 is a secondary coating. Each fiber is made of flexible silver halide or thallium halide and is encased in an easily deformable plastics or rubber tube, so that the resulting infrared light transmission path is also flexible. Each of the primary and secondary coatings serving as the flexible encasing may consist of two or more layers.
The infrared light transmission paths of
Figs. 3 and 4 are used in an optical temperature measuring system as shown in the block diagram of Fig. 5, wherein 6 is an object whose temperature is to be measured, 7 is an image forming optical system (lens), 8 is an infrared light transmission path, and 9 is a temperature measuring unit comprising a light detector and a signal processing section. By using more fibers and collecting more light, a temperature measuring system more sensitive than a single fiber can be produced. By connecting the individual fibers to respective light detectors, an image of temperature distribution, hence an image of heat rays, can be measured. By connecting a light detector to each of the fibers arranged in a row as in Fig.
4, a system capable of detecting the position of an object or detecting its movement according to a change in time can be produced.
The halide of the silver halide crystal, mixed crystal of silver halided, thallium halide crystal or mixed crystal of thallium halide can be fluoride, bromide, chloride or iodide. The fiber according to this invention is preferably composed of crystals having the same halide portion, but a mixed crystal can be those having different halides. A preferred silver halide is silver bromide or silver chloride.
The proportion of these crystals is not critical and can be any proportion in the fiber of this invention.
This invention is now described in greater detail by reference to the following example which is given here for illustrative purposes only and is by no means intended to limit the scope of the invention.
Example
A cylinder of ground silver bromide crystal was fitted into a hollow tube of ground silver chloride crystal to form an extrudable billet.
The billet was hot extruded at a temperature between 1 80 C and 350at to form a fiber 0.5 to 1.0 mm in diameter made of a silver bromide core and a silver chloride cladding. A hundred of these fibers were bundled into a cylinder and covered with a primary coating of heat-shrinkable tetrafluoride resin and a secondary coating of high-density polyethylene to thereby form an infrared light transmission path about 1.5 cm in diameter. A length of about 40 cm of the flexible infrared light transmission path was connected between the light source of a single-beam infrared spec froscope and a light detector.A spectroscopic analysis with this system gave a transmittance
between about 60% and 70% in a wavelength range of 1 to 1 5 microns, with the- reflection loss at both ends of the transmission path measured. The system could detect the light radiated from an object whose temperature varied from about 3000"K to about 2000"K, so it was found to be applicable to the measurement of temperature-.
As described in the foregoing, the infrared light transmission path of this invention uses fibers made of silver halide or thallium halide which transmit infrared rays, so it transmits a wide spectrum of light and can measure a wide range of temperatures. The fibers are flexible, and therefore a high degree of free dpm is allowed for connecting the transmission path between an object the temperature of which is to be measured (a light source) and a detector (a light detector). A higher sensitivity can be obtained by increasing the
number of fibers to be encased so as to
collect more light Another advantage is that
an image of iseat rays can be produced by
connecting detectors to the respective fibers.
The infrared light transmission path of this
invention is used with advantage in an optical temperature measuring system, position detector, image forming device for temperature
distribution, etc.
Claims (5)
1. An infrared light transmission path for transmitting heat rays which comprises a plurality of fibers of a silver halide crystal, a mixed crystal of silver halide, a thallium halide crystal or a mixed crystal of thallium halide, said fibers being encased in a rubber or plastic flexible coating.
2. An infrared light transmission path according to Claim 1, wherein said fibers are arranged in a cylindrical or flat form.
3. An infrared light transmission path a claimed in Claim 1, substantially as hereinbefore described with reference to, and as shown in, Fig. 1 or Fig. 2 and Fig. 3 or Fig. 4 of the accompanying drawings.
4. A temperature measuring system including an infrared light transmission path as claimed in any preceding Claim disposed between an object whose temperature is to be measured and a radiation detector capable of producing an output dependent on the wavelength of the radiation incident thereon.
5. A temperature measuring system as claimed in Claim 4, substantially as hereinbefore described with reference to, and as shown in, Fig. 5 of the accompanying drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6149880A JPS56156803A (en) | 1980-05-09 | 1980-05-09 | Infrared light transmission line |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2076988A true GB2076988A (en) | 1981-12-09 |
| GB2076988B GB2076988B (en) | 1983-11-09 |
Family
ID=13172814
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8114107A Expired GB2076988B (en) | 1980-05-09 | 1981-05-08 | Infra red transmitting light guide |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPS56156803A (en) |
| CA (1) | CA1159691A (en) |
| DE (1) | DE3118327A1 (en) |
| FR (1) | FR2482314B1 (en) |
| GB (1) | GB2076988B (en) |
| NL (1) | NL8102231A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0079708A1 (en) * | 1981-11-09 | 1983-05-25 | Sumitomo Electric Industries Limited | Infrared transmitting material consisting of silver chloride and silver bromide |
| EP0131918A2 (en) * | 1983-07-19 | 1985-01-23 | Gebr. Bindler Maschinenfabrik GmbH & Co. KG | Device for joining parts of an object together |
| WO2021209137A1 (en) * | 2020-04-16 | 2021-10-21 | Huawei Technologies Co., Ltd. | Thermal radiation detection device and system, as well as electronic device comprising such a device or system |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104991326A (en) * | 2015-07-24 | 2015-10-21 | 长飞光纤光缆股份有限公司 | Optical cable in central sleeve structure |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4217199Y1 (en) * | 1966-12-29 | 1967-10-03 | ||
| DE2513722B2 (en) * | 1975-03-25 | 1979-09-06 | Siemens Ag, 1000 Berlin Und 8000 Muenchen | Optical cable |
| DE2821642B2 (en) * | 1977-05-24 | 1980-02-07 | Hughes Aircraft Co., Culver City, Calif. (V.St.A.) | Fiber optic waveguides and process for their manufacture |
| US4170997A (en) * | 1977-08-26 | 1979-10-16 | Hughes Aircraft Company | Medical laser instrument for transmitting infrared laser energy to a selected part of the body |
-
1980
- 1980-05-09 JP JP6149880A patent/JPS56156803A/en active Pending
-
1981
- 1981-05-06 CA CA000376930A patent/CA1159691A/en not_active Expired
- 1981-05-07 NL NL8102231A patent/NL8102231A/en not_active Application Discontinuation
- 1981-05-08 DE DE19813118327 patent/DE3118327A1/en active Granted
- 1981-05-08 FR FR8109255A patent/FR2482314B1/en not_active Expired
- 1981-05-08 GB GB8114107A patent/GB2076988B/en not_active Expired
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0079708A1 (en) * | 1981-11-09 | 1983-05-25 | Sumitomo Electric Industries Limited | Infrared transmitting material consisting of silver chloride and silver bromide |
| EP0131918A2 (en) * | 1983-07-19 | 1985-01-23 | Gebr. Bindler Maschinenfabrik GmbH & Co. KG | Device for joining parts of an object together |
| EP0131918A3 (en) * | 1983-07-19 | 1986-02-12 | Gebr. Bindler Maschinenfabrik GmbH & Co. KG | Device for joining parts of an object together |
| WO2021209137A1 (en) * | 2020-04-16 | 2021-10-21 | Huawei Technologies Co., Ltd. | Thermal radiation detection device and system, as well as electronic device comprising such a device or system |
| CN114441046A (en) * | 2020-04-16 | 2022-05-06 | 华为技术有限公司 | Thermal radiation detection apparatus and system and electronic apparatus comprising such apparatus or system |
Also Published As
| Publication number | Publication date |
|---|---|
| DE3118327A1 (en) | 1982-04-01 |
| GB2076988B (en) | 1983-11-09 |
| NL8102231A (en) | 1981-12-01 |
| JPS56156803A (en) | 1981-12-03 |
| DE3118327C2 (en) | 1988-10-20 |
| FR2482314B1 (en) | 1986-06-20 |
| CA1159691A (en) | 1984-01-03 |
| FR2482314A1 (en) | 1981-11-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5113277A (en) | Fiber optic distributed temperature sensor system | |
| US4151747A (en) | Monitoring arrangement utilizing fiber optics | |
| US4307607A (en) | Temperature sensing arrangement and method | |
| US4295739A (en) | Fiber optic temperature sensor | |
| Klocek et al. | Chalcogenide glass optical fibers and image bundles: properties and applications | |
| US4362057A (en) | Optical fiber temperature sensor | |
| EP0606377B1 (en) | Optical fiber for spectroscopic monitoring | |
| JPS6156449B2 (en) | ||
| US3984332A (en) | Radiation detection system | |
| US4714829A (en) | Fibre optic sensing device and method | |
| CA2008515C (en) | Optical taper | |
| US4508461A (en) | Distributed fiber optic temperature monitoring apparatus and method | |
| GB2076988A (en) | Infra red transmitting light guide | |
| US4955979A (en) | Optical pyrometer with at least one fibre | |
| Kharaim et al. | On the Possibility of Application Infrared Crystalline Fibers for Transfer of Temperature Signals from Bearings inside Nuclear Power Plants’ Containment | |
| Klocek et al. | The development and applications of chalcogenide infrared optical fibers | |
| Saito et al. | Radiation thermometry for low temperatures using an infrared hollow waveguide | |
| Vázquez et al. | High spatial resolution optical fiber thermometers for applications in harsh environments | |
| JPH03277343A (en) | Temperature distribution measuring instrument for endoscope | |
| Campbell | Use of fiber optics in industrial infrared thermometry | |
| GB2162308A (en) | Wavelength detection | |
| Zur et al. | Theory of noncontact point thermal sensing by fiber-optic radiometry | |
| JPS6344134A (en) | Image guide type radiation thermometer | |
| GB2265711A (en) | Optical fibre sensors | |
| JPS63311307A (en) | Optical fiber type temperature sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19970508 |