RU2516926C2 - Railway traffic light - Google Patents

Abstract

FIELD: physics, signalling.

SUBSTANCE: invention relates to light signalling. The railway traffic light comprises an array of LED emitters mounted on its surface, said emitters being equipped with a separate or common optical system in form of aspheric lenses. The inner side of the lenses has recesses for fitting light emitters. Between the lenses and the LED emitters, there is an antiglare compound a refraction index n≥1.4 and which contains a mixture of silicone and absorbent nanoparticles with size of 0.1-1 mcm.

EFFECT: increased noise-immunity of the traffic light.

6 cl, 5 dwg

Description

The invention relates to the field of light signaling, and in particular to LED railway traffic lights, and can be used as a regulatory or warning device, which is installed along the route of railway transport and at level crossings.

Railway traffic lights are known (RU 93354, RU 98386, RU 36328, RU 60764, RU 2436196), containing at least one LED matrix, a light shaper, a power supply and a traffic light color control device connected via a control input to the railway automation system.

A disadvantage of the known railway traffic lights on LEDs is the relatively low noise immunity from artificial and intentional interference. This is due to the physical nature of the known LEDs and the possibility of changing their color glow when external short-wave radiation of the Sun or other sources of artificial and natural noise get on their phosphor layer. Ultimately, the distortion of the signal information of the railway traffic light can lead to the creation of emergency situations and crashes on the railways.

The closest in purpose and technical essence to the claimed invention relates to a railway traffic light (RU 2436196), containing at least one matrix of LED light emitters of the type LED or semiconductor crystal mounted on its front surface, equipped with individual and / or common optics, the optics being made in the form aspherical lenses, on the inside of which are recesses for installing light emitters.

In this case, the LEDs are made in the ultraviolet or optical range and are coated with a phosphor. The wavelength at the output of their phosphor is λ = 405-460 nm, and the coordinates of its color are in the range X = (0.36, 0.36, 0.47, 0.46) ± 0.001, Y = (0.37, 0 , 35, 0.43, 0.39) ± 0.01. Phosphor LEDs made by Stokes on the basis of garnets and silicates. From the outside, the matrix is covered with general (integumentary) optics (lens). The common lens is made in the form of a cut filter with a wall thickness of ≤1 mm to obtain the desired color coordinates in the yellow range. The space between the coating lens and the LED matrix is filled with a transparent or scattering sealing elastic compound with a refractive index of n≥1.3.

The disadvantage of this railway traffic light is the possibility of distorting its signal information (creating flare - a response light signal with a color different from the color of the probe signal that caused the response signal) under the influence of radiation irradiating the traffic light. The consequence of this is the possibility of emergencies and crashes on the railways when it is used to control rail traffic.

The objective of the invention is to increase the reliability of regulation of railway traffic by LED traffic light.

The technical result that provides the solution to this problem is to increase the noise immunity of the LED railway traffic light from artificial and natural interference by reducing the possibility of distortion of the signal information of the LED traffic light.

The achievement of the claimed technical result and, as a consequence, the solution of the problem is ensured by the fact that the railway traffic light containing at least one matrix of LED light emitters of the type LED or semiconductor crystal installed on its front surface, equipped with individual and / or general optics, the optics being made in in the form of aspherical lenses, on the inside of which there are formed recesses for mounting light emitters, according to the invention, between aspherical lenses and LEDs My light emitters installed an anti-reflective compound with a refractive index of n≥1.4, including a mixture of silicone and absorbing nanoparticles with a size of 0.1 to 1 μm.

Moreover, each matrix of LED emitters is made with the glow of its LEDs and / or crystals of yellow, red, green, blue or white. A yellow, red, green, blue LED contains a semiconductor crystal coated on the outside with a layer of a transparent organosilicon gel and / or gel-phosphor mixture, and a white LED contains a crystal coated on the outside with a layer of a gel-phosphor mixture of variable thickness, which ensures preservation white glow of the LED regardless of the angle of observation. To ensure the visibility of LED matrix radiation in the white frequency spectrum, the wavelength of the LED crystal coated with a phosphor was chosen equal to λ = 405-460 nm, and its chromaticity coordinates in the range X = (0.31, 0.31, 0.45, 0 , 45) ± 0.001 or Y = (0.306, 0.335, 0.42, 0.39) ± 0.001. The gel-phosphor mixture contains, wt.%:

Stokes phosphor - 1 ÷ 10

gel-like silicone - 90 ÷ 99.

An inorganic gel is selected with a refractive index of n≥1.4.

The installation between an aspherical lens and LED light emitters of an antiglare compound with a refractive index of n≥1.4, including a mixture of silicone and absorbing nanoparticles with a size of 0.1 to 1 μm, allows to reduce the access of external radiation, which changes the color of the indication of traffic signals, to the phosphor layer LEDs by attenuating its ionizing energy. This reduces the possibility of distortion of the signal information of the LED traffic light and, as a result, increases the noise immunity of the railway traffic light from artificial and natural interference.

A rational choice of the parameters of LED light emitters and their coatings allows you to additionally create the entire required color spectrum of anti-glare railway traffic lights to regulate the movement of railway transport.

The invention is illustrated by drawings, where figure 1 shows a LED railway traffic light with three indicator heads; figure 2 - indicator head traffic light with a matrix of LEDs and a common cover lens, top view; figure 3 is a vertical section along A-A of the indicator head of a traffic light with a matrix of LEDs with a common cover lens; figure 4 - the design of the LED with individual integumentary lenses, figure 5 - the design of the white LED.

The railway traffic light includes a protective housing 1 with LED heads 2 in yellow, red, green, blue or white, connected to a power source, a traffic light control device and a railway automation system (not shown). Each LED head 2 of a railway traffic light contains at least one matrix 3 of LED light emitters (LED 4 or semiconductor crystal 5) equipped with individual 6 and / or 7 common optics made in the form of aspherical coating lenses. On the inside of the coating lenses 6 and 7, recesses are formed for installing light emitters. Between the aspherical lenses 6, 7 and the LED emitters 4 or 5, an anti-glare compound 8 is installed with a refractive index of n≥1.4. Compound 8 includes a mixture of silicone and absorbing nanoparticles with sizes from 0.1 to 1 μm. The composition of the nanoparticles includes inorganic absorbing materials and is an element of KNOW-HOW. LED 4 yellow, red, green, blue contains a semiconductor crystal 5, coated on the outside with a layer of transparent organosilicon gel 9 with a refractive index of n≥1.4. and / or gel-phosphor mixture 10. The white LED 4 (Fig. 5) contains a crystal 5 coated on the outside with a layer of gel-phosphor mixture 10 of variable thickness, which ensures the white glow of LED 4 regardless of its viewing angle. For this, the layer 10 of the gel-phosphor mixture is made in the form of an aspherical gel-phosphor lens with the parameters:

$$D\left(\epsilon ,\beta \right)=R\left(\epsilon ,\beta \right)-R,\left(\mathrm{one}\right)$$

$$\epsilon =\{0÷90\},\left(3\right)$$

$$\beta =\{0÷180\},\left(\mathrm{four}\right)$$

Where D (ε, β) is the thickness of the gel phosphor lens;

TC - the color temperature of the radiation emerging from the LED;

R is the inner radius of the aspherical lens;

R (ε, β) is the outer radius of the aspherical lens;

ε is the direction of measuring the radiation intensity of the LED relative to its central axis in elevation;

β is the azimuthal direction of measuring the radiation intensity of the LED relative to its central axis;

n is the specific density of the phosphor in the gel phosphor lens;

j = j (ε, β) is the intensity of the blue radiation of the light-emitting element;

F {n, j} is the function of the dependence of the color temperature of the radiation emerging from the LED.

The numerical value of the function F {n, j} depends on the density of the phosphor, the intensity of the blue radiation of the light-emitting element at the angles ε and β, and its geometric parameters. The form of the function F {n, j} and the specific value of its parameters (1 ÷ 4) for a given color of the LED heads 2 is determined empirically at the experimental stand of Infoled LLC for each crystal 5 of the matrix 3 of LEDs 4. To ensure the visibility of the radiation of LED matrices 3 in the white frequency spectrum, the wavelength of the LED crystal 5, coated with layers 9 and 10, was chosen equal to λ = 405-460 nm, and its color coordinates in the range X = (0.31, 0.31, 0.45, 0.45 ) ± 0.001 or Y = (0.306, 0.335, 0.42, 0.39) ± 0.001. The gel-phosphor mixture 10 contains, wt.%:

Stokes phosphor - 1 ÷ 10

gel-like silicone - 90 ÷ 99.

Railway traffic light operates as follows.

According to a given program of railway automation, regulating the movement of railway transport, LED heads 2 of the corresponding color are turned on. When the LED head 2 is turned on, the light emitting elements (crystals 5) of the matrix 3 of the LEDs 4 emit light in the blue region of the visible spectrum. The blue radiation of the crystals 5 passes through the transparent gel layer 9 and is scattered in the front hemisphere, providing an increase in the output of blue light over the area of the radiation. Further, blue scattered radiation with an increased blue glow area compared to the emitting area of the crystal 5 from layer 9 penetrates through the interface of radius R into layer 10 of the gel-phosphor mixture of LED 4. The phosphor particles in layer 10 partially absorb the radiation, transform the resulting energy and during the luminescence process emit light in another yellow region of the visible spectrum, changing the color of the radiation, in particular, so that the total radiation of the LEDs 4 of the matrix 3 indicates It is also perceived by man as a plain white color. The specific type of color (yellow, red, green, blue, white) of each matrix 3 LEDs 4 is selected by the thickness of layer 10, the type and density of the phosphor in it. The implementation of the layer 10 in the form of an aspherical lens from conditions (1 ÷ 4) allows, by reducing its thickness D (ε, β) from the central axis to the periphery, to compensate for the decrease in brightness of the crystal 5 along the vertical angle 8 by reducing the number of phosphor particles in layer 10 on the way the propagation of blue photons, the total radiation of which and the radiation of phosphor particles is perceived by a person as monophonic, for example, white light, in the entire upper hemisphere of LED 4 of matrix 3. This ensures the color constancy of each LED 4 of matrix tsy 3 regardless of the angle of observation of its glow. Next, the monochromatic light of the LEDs 4 of the matrix 3 passes through an anti-reflective compound 8 with a refractive index of n≥1.4 with a slight attenuation at the boundary with the coating lens 6 or 7 and is emitted from the front of the traffic light of a fixed color. Due to this, on the light head 2 of the traffic light, its corresponding color signal for controlling railway traffic lights up. Since the composition of the absorbing inorganic material of compound 8 is tuned to a different frequency range other than the radiation frequency of the traffic light, light attenuation and clarity of the color indication of the traffic light heads 2 does not occur.

In the event that the traffic light of counter-interference radiation, for example, short-wave radiation (blue and ultraviolet) from the Sun or from the laser pointer of an intruder, gets onto the LED heads 2, this radiation is absorbed and scattered by the anti-glare compound 8. Due to this, the interference radiation energy does not reach the phosphor layer of 10 LEDs 4 or becomes insufficient to activate the phosphor and change the color of the heads of 2 traffic lights.

The present invention is not limited to the given example of its implementation. In the framework of this invention, other design options for LED railway traffic lights are possible. So as anti-reflective coatings and additives in this traffic light to further increase the noise immunity of the traffic light, dielectric compositions and additives known from / RU 2272329 / can additionally be used to cover the screens of gas-discharge indicator panels and including, wt.%: Silicon oxide - 2 ÷ 5; photoexposed dielectric material based on epoxy and acrylic resins - 95 ÷ 98. This composition requires high-temperature processing and can be applied with a thickness of 2 ÷ 5 μm only on the protective glass of the LED head 2 of the traffic light if it is present (not shown). Such a coating creates a rough anti-reflective surface that additionally scatters the interfering radiation before it enters the LED head 2. If the layer thickness is more than 5 μm, the coating will have a surface with a high degree of roughness, which reduces the brightness and clarity of the traffic signal. When the content of silicon oxide in the dielectric composition is less than 2 wt.%, And also when the anti-reflective layer is less than 2 mm thick, the anti-reflective coating effect is weakly expressed, since silicon oxide particles are rarely located on the surface of the protective glass and interfering short-wave radiation penetrates (in the absence of a compound layer 8 ) into the phosphor layer 10 of the LED 4, changing its color and creating a glare at a frequency different from the frequency of its causing.

The design of the railway traffic light is developed at the prototype level. Based on this design, prototypes of various modifications of noise-protected LED traffic lights for railway traffic service are currently developed. The measurement results showed that the noise immunity of the LED railway light from artificial and natural noise increased by at least 300%, and the unevenness of the color temperature on the surface of the light heads 2 of the traffic light significantly decreased and amounted to ± 100 degrees K.

Claims (6)

1. A railway traffic light containing at least one matrix of LED light emitters of the type LED or a semiconductor crystal equipped with individual and / or common optics installed on its front surface, the optics being made in the form of aspherical lenses, on the inside of which are recesses for installing light emitters , characterized in that between the aspherical lenses and LED light emitters installed anti-reflective compound with a refractive index of n≥1.4 and including a mixture of silicone and absorbing nanoparticles with a size of 0.1 to 1 micron. 2. The railway traffic light according to claim 1, characterized in that each matrix of LED emitters is made with the glow of its LEDs and / or crystals of yellow, red, green, blue or white. 3. The railway traffic light according to claim 2, characterized in that the yellow, red, green, blue LED contains a semiconductor crystal coated on the outside with a layer of transparent organosilicon gel and / or phosphor gel mixture, and the white LED is a crystal coated on the outside, a layer of gel-phosphor mixture of variable thickness, ensuring the preservation of the white glow of the LED regardless of the angle of observation. 4. The railway traffic light according to claim 3, characterized in that in order to ensure the visibility of the radiation of the LED arrays in the white frequency spectrum, the wavelength of the LED crystal coated with a phosphor is chosen to be λ = 405-460 nm, and its chromaticity coordinates in the range X = ( 0.31, 0.31, 0.45, 0.45) ± 0.001 or Y = (0.306, 0.335, 0.42, 0.39) ± 0.001. 5. Railway traffic light according to claim 3, characterized in that the gel-phosphor mixture contains, in mass,%:
- Stokes phosphor - 1 ÷ 10;
- gel-like silicone - 90 ÷ 99. 6. Railway traffic light according to claim 3, characterized in that the organosilicon gel is selected with a refractive index of n≥1.4.

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