Fiber optic lighting in ATEX zone

Fri, 15 Apr 2022 15:17:00 +0200

Preambule

There are a number of LED lightings available for operation in explosive atmospheres. These lighting devices such as lights, projectors, street lamp smust follow ATEX directives and standards if they are intended to be used in an ATMosphere Explosible zone or ATEX. These ATEX lights are generally very expensive to respect these environmental constraints, there are fortunately fiber optic lighting alternatives.

LED lighting in ATEX zone

An ATEX zone is defined according to its degree of danger. It is linked to an atmosphere explosible characterized by a mixture of flammable substances with air. This mixture may consist of gases, vapors, mists or dust. After ignition of this mixture, the combustion spreads to the whole of the unburned mixture.

The types of blast can be linked to a chemical reaction, the sudden rupture of a pressurized container with the release of a large amount of energy stored under pressure or the ultra-rapid vaporization of a pressurized and superheated liquid.

Waterproof diffusing light guide on the ground
Tue, 24 Nov 2020 14:44:00 +0200

Use of luminous diffusing guide on the ground

It is now possible to make lighting on the ground,signage on a waterproof resin-based coating. This light diffusion takes place on a contour without supply of electricity thanks to the use of optical fiber diffusing and remote light source.

This light diffusing guide consists of a set of diffusing fibers inserted into a profile filled with transparent or phosphorescent granules. The injection of light into the diffusing guide is done via a light generator.
The bundle of diffusing fibers is conditioned to have a homogeneous diffusion of light over a given length. This homogeneous diffusion results in a constant diffusing light over a whole length from a light source to a point furthest from this light source

The resin protects the fibers when walking onthem and its transparency allows the light emitted by the fiber to be reflected back. This resin can also be phosphorescent, it can become UV...

Plastic optical fiber weaving
Wed, 22 Apr 2020 14:01:00 +0200

Uses of luminous optical fiber fabric

Several textile manufacturers have started to integrate light optical fiber into their textiles naturally. If the first tests were successful on clothing, the first bright textiles were produced for interior fittings, hotel decoration or for marketing at points of sale.

Since then, these luminous fabrics have developed for a number of uses far removed from the "designer and decorative luminous fabric", particularly in the medical field. Today there are several medical applications such as the treatment of jaundice in infants or the treatment against pre-cancerous skin bonds which require the use of a luminous tissue in a particular wavelength.

Implementation of luminous optical fiber weaving
Weaving approach

This weaving can be done from traditional weaving looms such as the Jacquard loom but also from...

Custom fiber optic light source
Fri, 17 Apr 2020 09:54:00 +0200

Preamble

For your visible fiber optic light guide projects, it is imperative to choose your LED light source carefully. Most of the time, we can be satisfied with light sources existing on the market if we do not have particular requirements such as compactness, advanced optical characteristics, luminous efficiency, wavelength. This light source connected to the light guide allows light to be shifted to one or more points in often restricted spaces.
The luminous efficiency of a light guide is closely linked to its coupling with its light source.
In the industrial sector, discreet light sources at reasonable prices are sought after if volumes are expected. In this case there is no other choice than to design a light source for its own use with the expected light guide.
Defnition of light source specifications

These specifications must be determined by the use of the light guide with expected light requirements (wavelength, lighting level) and space constraints.
This first expression of need must make it possible to select :

Nature of the light guide: illuminating optical fibers (light point at the end of the fiber) versus...

Polymer optical fiber with large numerical aperture
Fri, 17 Apr 2020 09:54:00 +0200

Propagation modes within polymer optical fiber
A plastic optical fiber with index step consists of a transparent PMMA(Polymethyl Methacrylate) core and a cladding of fluorinated polymer with a refractive indexlower than that of the core. The confinement of light within the fiber is donethanks to the phenomenon of total internal reflection.

Fibers supporting many propagation paths for light or transverse modes are called multimode fibers as opposed to single mode fibers which only support one mode.

Optical fiber is a waveguide which exploits the refractive properties of light. A step index optical fiber is also characterized by its numerical aperture NO which defines the maximum angle of light at the entry of the fiber for its reflection within the fiber, namely the aperture of the acceptance cone . The theoretical value of the numerical aperture is calculated according to the refractive indices n_c of the heart and n_g of the cladding :

PMMA refractive index is around 1.49.

Reading light in polymer optical fiber
Fri, 20 Mar 2020 17:25:00 +0200
Use of plastic optic fiber reading light

A fiber optic reading light provides a reading function in a place where it is inappropriate to put classic lighting in it. The optical fiber then makes it possible to deport lighting by installing a light source with its power supply in a place without risk on its general functioning but also on an environment sensitive to electromagnetic disturbances, or on the safety of materials or people.
The optical fiber which only conducts light does no thave any sealing defects compared to conventional lighting with its electrical circuit. This characteristic makes it possible to respond to a problem of sealing in any lighting exposed to splashing water, for example in a boat or aboat cockpit.
It can be recommended to avoid generating electromagnetic disturbances caused by a power supply of conventional lighting.The optical fiber does not generate any electromagnetic disturbance, makes it possible to respond to this constraint, in particular for lighting of control centers such as for example cockpits of planes or helicopters.
For obvious safety rules, It is inappropriate to put a light source in contact with flammable material, or a person. This is the case,for example, where you must integrate a reading light in a car, train, planeseat ... The use of fiber for lighting makes it possible to eliminate any risk linked to an electric short-circuit. maintenance of the assembly is all the easier as the plastic optical fiber is maintained over time, it comes down only to the maintenance of the light source for all the reading lights.

Insensitivity to X-rays of polymer optical fibers
Thu, 12 Mar 2020 17:51:00 +0200
Radiation tests on polymer optical fibers
Polymer optical fiber is found in various fields such as lighting, data transmission in an industrial environment, sensors, medicine, audio cables.These plastic fibers are made of PMMA (Polymethyl Methacrylate), a thermoplastic polymer offering very high light transparency in the visible range. These plastic optical fibers also have the distinction of resisting electromagnetic disturbances but also of being easy to handle unlike optical fibers based on silica. They also represent an economical alternative to optical fibers based on silica and are often used to transport light from one place to another. These fibers can be exposed in environments with high radiative stresses.
We wanted to test whether these plastic optical fibers were sensitive to X-ray irradiation. Indeed, the fibers can be put in extreme conditions whetherin space, nuclear. When the optical fibers are sensitive to radiation, we observe a phenomenon of radio darkening with a degradation of transmission of the fiber; these are linked to the appearance of an absorption band on theoperating spectrum of the fiber.

Radiation results on polymer optical fiber

The Institute of Physics of Nice (INPHYNI, University of the Côte d'Azur -UMR 7010 of CNRS) carried out this test by exposing...

Flexible image guide
Mon, 10 Feb 2020 13:58:00 +0200
General around flexible image guides

Flexible image guides have established themselves in the industry to capture images in dangerous or difficult-to-access areas. Many cameras and sensors are used in the industry to monitor processes. It is inappropriate to install them in a harsh environment either because of the risk of damage or because of the risk to the environment itself. A harsh environment can be characterized by very high temperatures, strong magnetic fields, strong pressures, strong irradiations; it can contain a very explosive environment, it can also be located in confined spaces.
A flexible image guide made up of over a hundred thousand glass fibers enables high-resolution images to be transmitted without risk from a sensitive area to a camera, camera, chip or installed monitoring station in a safe and easily accessible area.

Each pixel is transmitted coherently by each of fiberglass strands constituting the image guide, so that the individual position of each strand is identical at each end of the image guide.

The diameter of the fiberglass strand defines the size of the pixel. On the other hand, there is no risk of causing electronic interference given the nature of the fiber optic image guide.
These optical fibers can...

Overview of polymer optical fiber
Mon, 3 Feb 2020 17:41:00 +0200

General information on polymer optical fibers

Polymer or plastic optical fiber is found in various fields such as lighting, waveguides, data transmission in an industrial environment, sensors, medicine, audio cables. They have the distinction of working well in the visible area as shown by this attenuation curve of a standard fiber of the brand Toray.
These polymer fibers consist of a large PMMA (Polymethyl Methacrylate) core, and a cladding made of fluorinated polymer. The thickness of the cladding can represent 1% of the diameter of the heart. This fiber is a waveguide which exploits the refractive properties of light with a confinement of light between the core andthe optical cladding by multiple reflection at the interface of these two materials (phenomenon of total internal reflection).

As the core diameter of this fiber is important; the fiber behaves like a multimode fiber; the light rays injected will follow different paths according to their angles of incidence in the fiber. We also define the numerical aperture of the fiber which characterizes the maximum angle of light input into the fiber through the light can be guided.

The, majority of polymer optical fibers are step-index profile, that is to say that the core has a refractive index n_c and the cladding has a refractive index n_glower than the refractive...

Blog

Fiber optic lighting in ATEX zone

Preambule

LED lighting in ATEX zone

Waterproof diffusing light guide on the ground

Use of luminous diffusing guide on the ground

Plastic optical fiber weaving

Uses of luminous optical fiber fabric

Implementation of luminous optical fiber weaving

Custom fiber optic light source

Preamble

Defnition of light source specifications

Polymer optical fiber with large numerical aperture

Propagation modes within polymer optical fiber

Reading light in polymer optical fiber

Use of plastic optic fiber reading light

Insensitivity to X-rays of polymer optical fibers

Radiation tests on polymer optical fibers

Radiation results on polymer optical fiber

Flexible image guide

General around flexible image guides

Overview of polymer optical fiber

General information on polymer optical fibers