CZ2018746A3 - Light-beam optic modulator, especially for the infrared area - Google Patents

Abstract

The light-beam optic modulator, particularly for the infrared region, comprises an optical element (1) comprising (a) electro-optical or magneto-optical glass with optically active nano and / or micro particles; (b) has an inlet surface (2) and an outlet surface (3), both surfaces (2, 3) being optically polished; and (c) embedded in a dielectrically insulating glass material. The optically active nano and / or microparticles have a size of 0.1 nm to 50 µm, preferably 0.5 nm to 100 nm. The inlet and outlet surfaces (2, 3) may be provided with an antireflective layer. The entrance surface (2) is preferably provided with an optical glass fiber (7). To form an electro-optical modulator (EOM1, EOM2), the optical element (1) is connected to its electrodes (8) on its opposite side walls (1c, 1d). To form a magneto-optical modulator (MOM1, MOM2), the optical element (1) is inserted into an electromagnet with a coil (10) and a coil winding (11) of the electromagnet. The optical element (1) has glass carrying optically active nano and / or microparticles, a low-melting, preferably lead-bismuth glass. The optically active nanomicroparticles may be electro-optically active, preferably metal with at least one of Ag, Au, Pt and Cu. The optically active nano and / or microparticles may be magneto-optically active, from the group of metal oxides / oxide compounds including FeOa magnetite / or NiFeO trevorite, and / or nickel-cobalt ferrite (NiCo) FeO, and / or gamma hematite FeO; optionally they may additionally contain at least one lanthanide oxide such as praseodymium oxide PrO and / or dyspropium oxide DyOa / or terbium oxide TbO. The dielectric insulating glass material is selected from the group of glass based on at least one of SiO, BO, PO, VO, MoO, WOa and alkali oxides such as LiO, NaO, KO and RbO and divalent oxides such as MgO, CaO, BaO and ZnO .

Description

Technical field

BACKGROUND OF THE INVENTION The present invention relates to a free-light optic light modulator, particularly for the infrared region. The modulator comprises an active optical element connected to the electrodes or embedded in a magnetic field.

BACKGROUND OF THE INVENTION

Light modulators are designed to modulate a light signal in terms of changing light intensity or phase. For modulating the light, an electric or magnetic field is used which acts on a suitable electro-optical or magneto-optical material.

Electro-optic material is described, for example, in US 6859467 B2. Electro-optical material is the basic element of the electro-optical modulator with laser source. The electro-optic material comprises a crystalline chemical composition, represented by the pattern RcAc4O (BCl ·). wherein Re comprises one of La, Ce, Pr, Nd, Srn, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, and two other elements Y and Sc; and wherein Ae is from Ca, Sr or Ba. Specifically, the crystal composition of YCa4O (BO3) 3 referred to as YCOB or its isostructured variants of GaCOB or LaCOB is disclosed. The modulator of this crystalline material is provided with elongated electrodes which provide an electrical voltage, the intensity of which is conducted across the electro-optical crystal, thereby achieving a phase delay of the polarized laser beam passing through the crystal. In said type of modulator based crystals can replace commonly used YCOB BaB ₂ O4 crystals known as BBO. The advantage of YCOB-based crystals is the much easier technology of growth of these crystals, their polishing, optical bonding and thin-film coating. The crystalline materials used require adherence to exact stoichiometric ratios between their constituent elements in order to provide the desired crystal structure, which requires relatively precise adherence to the crystal manufacturing technology. Even small deviations from stoichiometry cause an undesirable change in their crystalline structure, which can lead to a deterioration of the electro-optical properties, a difficulty in crystal growth technology, their polishing, optical bonding and thin film deposition. Therefore, the chemical composition cannot be varied within a wider range of compositions in order to optimize their physico-chemical properties. The production of these materials will be quite complex and therefore expensive.

Another electro-optical material is described in US 2018/0364501 A1, which is embedded in an electro-optical modulator. The modulator comprises an insulating layer; a central optical waveguide mounted on an insulating layer; a first region with a doping type facing the first side wall of the central optical waveguide; a second region having a p type of doping situated opposite to the first doped region and facing the second wall of the central optical waveguide; a thin dielectric layer extending through the central electro-optical element from its upper surface to its lower surface. The insulating layer is made of a material with a high dielectric constant, including ZrO ₂ , Al ₂ O 3, HfOx, HfSiOx, ZrTiOx, TaOx and a laminated layer of oxides ZrO ₂ -Al ₂ O ₃ -ZrO ₂ (ZAZ), SrTiCE, BaTiCE, BaSrTiCE (BST ) or PbZrTiCl · (PZT). The central optical waveguide comprises an inner crystal 1 and an inner crystal 2 forming plates which, on one side and the other, abut a central dielectric material through which the modulated optical signal passes. In the exemplary embodiments, the first doped region adjacent to the central waveguide region is the Si-doped layer. At the same time, as the second doped region, which on the other side adjoins the central waveguide region, the Si layer with the p-type doping. The design of this modulator uses a relatively complex structure with doped crystalline materials to ensure its functionality. The disadvantage is complex production with expensive special crystalline components. This type of material and modulator design is likely to allow the production of miniature elements and their integration into an integrated optics assembly. This

However, miniaturization in the form of thin films does not allow the modulation of a higher energy light signal and will therefore be less suitable for free-time optics. Also, the production technology of these materials is likely to be demanding in terms of the exact composition and purity of the components as well as the preparation process to ensure the necessary optimal crystalline structure. These necessary conditions combined with the relatively complex construction of the modulator itself will most likely lead to high production costs of the modulator.

A suitable magneto-optical material for electromagnetic light modulators is less utilized compared to the electro-optical material. However, due to ongoing research and development, the use of these materials in light modulators is becoming increasingly important. Magneto-optical material is described, for example, in US 6392784 B1 entitled Faraday Rotator. The disclosed apparatus utilizes an electromagnetic field acting on a magneto-optical material to achieve rotation of the plane of polarized light. This device comprises a number of Faraday magneto-optical elements. Permanent magnets produce a magnetic field that acts in a direction parallel to the direction of propagation of the optical signal, and at the same time the electromagnet generates another magnetic field acting in a direction perpendicular to the direction of propagation of the optical signal. Faraday magneto-optical elements consist of crystals whose direction of crystal orientation is perpendicular to the direction of propagation of the optical signal. The directions of adjacent Faraday crystalline elements are opposite to each other. The composition of the magneto-optical material constituting the crystalline Faraday elements is set forth in claims 5 to 8 of the patent. In claim 5, the composition of these crystals is of the formula (RBi) Tc-O12 or (RBi) Tc-O12. wherein R is one or more of the rare earth elements that may be replaced by iron. These crystals are obtained by liquid phase epitaxial growth technology. In claim 6, the crystal composition of Faraday elements is shown by the formula Y ₃ Fe 50 ₁₂ . According to claim 7, the Faraday rotator can also be used as an optical signal attenuating element in the arrangement of claim 8, wherein the polarizer is upstream of the Faraday rotator and the analyzer downstream of the rotator. The described method of arrangement of individual Faraday elements enables to compensate the temperature dependence of the magneto-optical effect on these crystals and thus reduces the influence of temperature on the functionality of the Faraday rotator. The use of crystalline materials, which must maintain a given ratio of chemical elements to the crystalline structure, does not allow a significant modification of the composition in order to optimize their properties, for example to obtain their precisely tuned assembly in this rotator. This rather complicated construction has to be assembled very precisely, which is obviously quite technically demanding and expensive.

Another type of magneto-optical material for electromagnetic light modulators is described, for example, in US patent 2010/0142028 A1 entitled Magneto-optical optical modulator. The apparatus described herein is used to modulate an optical light beam. The apparatus consists of a substrate of non-ferromagnetic material on which is a thin film of ferromagnetic semiconducting material. The design allows at least a portion of the optical beam to reflect from this thin layer. This layer reacts to the inserted variable magnetic field by changing the polarization of the light beam that is reflected from this layer. The chemical composition of the ferromagnetic semiconductor layer is based on a (III, Mn) V type semiconductor, in particular InMnAs or AISbAs, and also other layers may consist of the compounds AISb, GaSb and GaAs. Said magneto-optical modulator allows efficient transmission of information encoded directly due to possible modulation of the reflected radiation polarization. Said thin film technology enables miniaturization for integration into an integrated optics system where low energy optical signals are used. The materials used based on arsenides and antimonides have weaker bonds and therefore lower chemical stability. Therefore, in the modulation of higher energy optical signals for free-time optics, these materials could degrade and lead to irreversible changes in their magneto-optical properties.

SUMMARY OF THE INVENTION

These disadvantages will be avoided or substantially reduced by the free-light optic light modulator, especially for the infrared region, comprising the optical element according to the invention, whose

-2GB 2018 - 746 A3 is that the optical element:

comprising a glass block of a PbO-Bi2C> 3-Ga2O glass array with optically active nano and / or microparticles which provides electro-optical or magneto-optical properties, the optically active nano and / or microparticles having a size of 0.1 nm to 50 nm pm; having an entrance surface and an exit surface, both surfaces being optically polished and the polished surfaces being covered with an anti-reflective layer, the entrance surface being further provided with an optical glass fiber (7); and is embedded in a dielectric insulating glass material selected from the group of glass based on at least one of the oxides S1O2, B2O3, P2O5, V2O5, MoOs, WO3 and alkali oxides such as L12O, Na2O, K2O and Rb2O and divalent oxides such as MgO, CaO, BaO and ZnO.

The main advantage of the present invention is the glass state of the optical element. Its structure is therefore predominantly amorphous and it is possible to vary the ratios between the chemical components of this material within a relatively wide range. This property of glass enables efficient tuning and optimization of its chemical composition and creation of a suitable chemical environment for optically active nano and / or microparticles. This results in a high electro-optical or magneto-optical effect under the influence of an electric or magnetic field, which is the basis of the modulation of polarized light in this modulator. Another advantage is the easy production and processing of glass as well as the assembly of the modulator from a relatively small number of components. The modulator is based on glass materials that are cheap, easy to manufacture and deformable. Moreover, their properties, such as primarily optical, electrical, magnetic and mechanical properties, can be easily fine-tuned and mutually optimized by chemical composition and thermal history during their manufacture.

Selected dielectric insulating glass material selected from the group of glasses based on at least one of the oxides S1O2, B2O3, P2O5, V2O5, MoOs and WO3 and alkali oxides such as L12O, Na20, K2O and Rb2O and divalent oxides such as MgO, CaO, BaO and ZnO ensures that by a suitable combination of these elements it is possible to obtain a glass material of the pad / cover with good optical, dielectric, mechanical properties allowing efficient modulator operation.

It is preferred that the optically active nano and / or microparticles have a size of 0.1 nm to 50 µm, preferably 0.5 nm to 100 nm. An optical element with optically active particles of these sizes achieves a high electro-optical and / or magneto-optical effect with good transmission in the infrared range of the spectrum.

In an advantageous embodiment, the optical element is formed in the form of a longitudinal prism of the glass, with longitudinal surfaces, namely a longitudinal lower surface, an opposed longitudinal upper surface, between which opposite longitudinal side surfaces are situated. The longitudinal surfaces delimit the opposed situated optically polished entry / exit surfaces. The prism of the optical element may be made of electro-optical or magneto-optical glass. The dielectric insulating glass material consists of a bottom pad and an upper cover. The glass state of the optical element, the substrate and the cover allows for easy and efficient grinding, polishing and connection to any other optical elements, such as inlet glass fiber.

Preferably, the inlet and outlet surfaces are provided with an antireflective layer. This reduces the optical loss at the optical input and output of the modulator.

Preferably, the input surface of the optical element is provided with an optical glass fiber, which allows the use of fiber input laser sources and miniaturization of the modulator.

In order to form an electro-optical modulator, it is advantageous for the optical element to be connected to longitudinally located lead electrodes on its opposing side walls. The electrodes are preferably planar.

In order to form a magneto-optical modulator, it is advantageous if the optical element is inserted into the electromagnet with the coil and the coil winding of the electromagnet, while on the coil winding

A3 of the electromagnet are connected to the AC power supply.

It is also preferred that the glass carrying the optically active nano and / or microparticles is low-melting, preferably based on lead-bismuth glass. Glass is easy to melt and heat and mechanically process, ie cuts, grinds and polishes. It also creates a favorable environment for the electro-optically and magneto-optically active nano and / or microparticles, thereby enhancing their electro-optical or magneto-optical effect in the electric or magnetic field. These glasses also have high transmittance in the infrared range of the spectrum.

Optically active nano and / or microparticles may be electro-optically active or magneto-optically active. Their given chemical composition, their size and placement in the surrounding optimal glass matrix ensures their high optical activity in the electric and / or magnetic field.

For the electro-optical modulator, the optically active nano and / or microparticles are electro-optical. The electro-optically active nano and / or microparticles are metal and comprise at least one metal selected from the group consisting of Ag, Au, Pt and Cu in the form of crystalline and / or partially crystalline nano and / or metal microparticles. Because of this chemical composition, a high electro-optical effect in the alternating electric field is achieved, which is favorable for the construction of a fast-response modulator in the infrared spectrum.

For the magneto-optical modulator, the nano and / or microparticles are optically active. The magneto-optically active nano and / or microparticles are crystalline and / or partially crystalline from the group of metal oxides / oxides, including magnetite Fc? Ch and / or trevorite NiFe2C> 4, and / or nickel-cobalt ferrite (NiCo) Fe2C> 4 , and / or gamma-hematite Fe 2 C 3. Because of this chemical composition, these nano and / or microparticles achieve a high magneto-optical effect in an alternating magnetic field, which is favorable for the construction of a modulator with a very fast response in the infrared spectrum.

Further, the optical element may further comprise at least one lanthanide oxide selected from the group consisting of praseodymium oxide Pr ₂ O ₂ . and / or Dy ₂ O dyspropium oxide, and / or Tb 2 CO 3. The presence of these oxides in the glassy magneto-optically active optical element increases its magneto-optical effect, which is favorable for the construction of a modulator with very fast response and low attenuation in the infrared spectrum.

Clarification of drawings

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an axonometric view of an electro-optical modulator; FIG. 2 is an axonometric view of an electro-optical modulator with a fiber optic inlet; AA of FIGS. 1 or 2, FIG. 4 is a longitudinal section of a magneto-optical modulator and FIG. 5 is a longitudinal section of a magneto-optical modulator with an optical glass fiber at the inlet.

DETAILED DESCRIPTION OF THE INVENTION

The light modulator for free-time optics, intended especially for the infrared region is

-4GB 2018 - 746 A3 is described in detail in the following non-limiting embodiments, and is designated E0M1 for an electro-optical modulator, E0M2 for an electro-optical modulator with glass fiber optic 7, M0M1 for a magneto-optical modulator and M0M2 for a magneto-optical modulator with glass fiber 7.

An essential part of E0M1 modulators. E0M2, M0M1 M0M2 is an optical element 1 with an inlet surface 2 and an outlet surface 3. In an exemplary embodiment, the optical element 1 is in the form of a longitudinal prism with a longitudinal lower surface 1a, an opposite longitudinal upper surface 1b and longitudinally opposed side walls 1c and 1d. The longitudinal surfaces 1a, 1b, 1c, 1d define a shorter inlet surface 2 and an opposed shorter outlet surface 3. The inlet surface 2 and the outlet surface 3 are preferably optically polished and may be provided with an antireflective layer. The optical element may be made of electro-optical or magneto-optical glass.

The optical element 1 and its longitudinal surface 1a, 1b, respectively. lc. Id. they are housed in insulating dielectric glass. In particular exemplary embodiments, the prism of the optical element 1 is embedded in the insulating dielectric glass lower substrate 5 and the insulating dielectric glass upper housing 6.

Connected to the optical element 1 on the opposite longitudinal side walls 1c, 1d of the longitudinal electrode 8 with leads 4 to form the electro-optical element E0M1. E0M2. In an exemplary embodiment, these electrodes 8 are planar.

An optical glass fiber 7 can be connected to the input surface 2 of the modulators, which then forms an electro-optical modulator E0M2 or a magneto-optical modulator M0M2.

The optical element 1 may be inserted into an electromagnet with a coil 10 and a coil winding 11, and thus a magneto-optical modulator M0M1 or M0M2 with an optical glass fiber 7 is formed at its input 2. The coils 11 to the not shown are connected to the coil winding 11. AC power sources.

For dielectric insulating glass material, glass based on at least one of SiO ₂ , B ₂ O ₃ , P ₂ O ₅ V ₂ O ₅ , MoO ₃ and WO ₃ and alkali oxides such as Li ₂ O, Na ₂ O, K _{2 is} suitable O and Rb ₂ O and oxides of divalent oxides such as MgO, CaO, BaO aZnO.

As glass with electro-optical properties, it is suitable and successfully tested glass according to the document CZ 307135 of the same applicants and producers.

As glass with magneto-optical properties, it is suitable and successfully tested glass according to the document CZ 307 666 of the same applicants and producers.

Example 1

Electro-optical modulator E0M1, E0M2 (Fig. 1,2,3) '

Design of the optical element

Less costly components are used to design a free-range transverse electro-optical modulator. For electro-optic active element is used optimized EOS glass system PbO-Bi ₂ O3-Ga ₂ O3 with nanoparticles Ag °, whose composition is shown in Tab. AND.

After melting and casting into the metal mold, the obtained glass blocks were heat treated to control the formation of the desired Ag0 metal nanoparticles. Then these blocks were mechanically modified into prisms for the optical element 1, on whose side walls 1c, 1d were sputtered with Ti

The electrodes 8 were then inserted into the insulating dielectric glass, the washers 5 and closed from above by the cover 6 constituting the structure of the modulators E0M1, E0M2. The glass optical element 10 was formed in such a way that the glass prism was cut with a wire cutter and ground to a longitudinal prism, most often with a length of 25 mm, a width of 9 mm and a height of 13 mm. The cell and the longitudinal sides of the prism were ground in parallel and polished to optical quality. The preparation of the optical surface of the samples to form the optical element 1 by grinding and polishing took place on a surface grinder Montasupal. Suspensions of free particles of alumina - corundum and cerium oxide in distilled water were used as abrasive and polishing material. Corundum abrasive F800, grain size F800 was used for coarser sample grinding to achieve the desired thickness faster, and cerium oxide, under the trade name Tecepol KF250, with a grain diameter D50 (1-2 µm), was used for polishing the surface to optical quality. Grinding was performed on cast iron wheels and the abrasive suspension was added dropwise from the stock bottle. For polishing the ceroxide suspensions, soft discs under the trademark Polpur AB were used, with a layer of fine, fibrous support impregnated with a thermoplastic polyurethane resin. Also, the polishing agent was added dropwise continuously throughout the polishing process. Since the surface quality of the polished glass is important in order to eliminate unwanted scattering of optical radiation on surface irregularities, the entire polishing process has been designed for both devices based on SEM electron microscope surface inspection.

1.2 Creating Electrodes 8

Over the entire area of the long sides 1c. The id of the optical element 1 was vaporized by titanium electrodes 8 with an approximate thickness of 200 nm. Electron Beam Plasma Vapor Deposition (EBPVD) technique was used for steaming. The steaming process took place in the Balzers BAK600 steam chamber and the actual deposition of the layer was controlled by the INFICON SQC-310. During the vapor deposition vacuum chamber was 1.5 · 10 ^-6 mBar and deposition rate of the Ti electrode 8 was 5a with ^_1.

1.3. Design of electro-optical modulator E0M1, E0M2

Modulator E0M1, E0M2 was made in plastic construction box made of ABS plastic, length 50 mm, width 35 mm and height 20 mm. An optical element, a ground glass block with electro-optical properties, was attached to the bottom thereof. On the two longer opposite walls of the optical element 1, the leads 4 were conductively contacted to the steamed Ti layer of the electrodes 8, which were connected to the gold-plated SMA connectors on the longer opposite sides of the plastic box. These connectors are used to connect the poles of the modulation voltage supplied from a high-voltage power supply by 5 mm diameter RG58 coaxial cables with a 50 im impedance.

In the construction of the E0M1 modulator, holes for the input surface 2 and the output surface 3 of the free laser beam were drilled at the intersection of the longitudinal axis of the prism with the shorter sides of the plastic box, which are modulated when passing through the glass prism of the optical element 1.

In the construction of the E0M2 modulator, holes for the inlet surface 2 and the outlet surface 3 of the free laser beam were also drilled at the intersection of the longitudinal axis of the prism with the shorter sides of the plastic box, and glass fiber optic 7 was glued to the inlet surface 2 using a fiber field. grooves) on the entrance surface 2 of the optical element 1.

Nufem PM1950, for a wavelength of about 2000 nm, and Nufem PM460 for the 650 nm region were chosen as suitable optical glass fiber 7 in view of the requirement to maintain polarization of optical radiation.

In more detail:

Optical glass fiber 7, of the Nufem PM460 type, is transmissive to the infrared region of light in the range of 1850 to 2200 nm and is made on the basis of S1O2 doped with GeO2. The specific wavelength is set by a suitable source, an activity known to one of ordinary skill in the art.

-6GB 2018 - 746 A3

Optical glass fiber 7, of the Nufem PM1950 type, is also made of a S1O2-based material doped with GeO2 and is transparent to the visible light range in the range of 460 to 700 nm. The appropriate wavelength of the glass fiber 7 is set by a suitable source and routine to one of ordinary skill in the art.

1.4 EPS glass composition for electro-optical modulator E0M1, E0M2 and its parameters

Table I

Glass components Example 1 [wt%] PbO 60.2 BI2O3 38.7 Ag 0.6 Ouch 0.0 Pt 0.0 Cu 0.0 Sb2C> 3 + Sb20s 0.5 AS2O3 + AS2O5 0.0 SiO ₂ 0.0 Sum 100.0 Melting point t _m [° C] 980 Heat treatment temperature [° C] 340 Heat treatment time [min] 10 Stability against devitrification stable Mean nanoparticle size [nm] 23 Electro-optical coefficient b [m · V ^-2 ] 2,3.10- ¹¹ Transmittance T [%] for wavelength 2100 nm, glass thickness 1 cm 73 Refractive index n at 1311 nm 2.39 Evaluation Great

Optical glass fiber 7 was terminated with an FC / APC connector to connect a pigtail laser source. The output surface 3 of the optical element 1 is then free-again. In order to eliminate reflections at the interface of the individual optical environments, the fiber field and the optical element 1 are glued at an angle of 8 ° to each other. Alignment must be carried out on 15-piezo optic tables to ensure the lowest possible input losses.

1.5 Testing of electro-optical modulator E0M1, E0M2

For testing functional samples of E0M1 modulators. E0M2 created measuring assembly

-7GB 2018 - 746 A3 based on polarity light transmittance measurement. When testing functional samples of the E0M1, E0M2 free-range modulators, the electrical signal on the electrodes 8 was modulated by rectangular DC voltage pulses ranging from 0 to a maximum of 27 kV in the frequency range 1 Hz to 100 MHz using the Rigol wave function generator. As a result of the applied electrical voltage, the refractive index of the glass of the optical element 1 changed and thus the transmittance of the optical system changed when the polarizer and the analyzer were rotated relative to each other. When modulating the applied voltage in the modulator E0M1. E0M2 modulated the intensity of the output free-time optical signal. The results of measurement of electrical modulation and optical output using the Rigol oscilloscope were saved to a computer and subsequently processed. By analyzing the measured response spectra of the modulator optical signal recorded by the oscilloscope, the response times of the optical signal of the constructed EOMI modulators were determined. E0M2.

Engineered E0M1 modulators. E0M2 with optimized glass from the PbO-EUO system, Ga2C> 3 with Ag ° nanoparticles with a mean particle size of 23 nm exhibited response times shown in Table II. Response times were significantly shorter than Ips. The optimized EOS glass had a sufficiently high electro-optical coefficient and proved to be suitable for the construction of a functional sample of the free-range electro-optical modulator E0M1, E0M2 for a wavelength of 2100 nm with a fast response below 1 ps.

1.6 Parameters of electro-optical modulator E0M1, E0M2

The chosen production technology was verified and produced by modulators E0M1. E0M2 met the required properties. The advantage of modulators is the good affordability of its components and its undemanding design. The electro-optical glass of the optical element 1 contains economically advantageous components and its production, shaping and subsequent processing is not expensive.

Table II

Modulator Response time τ [ns] Attenuation for 2100 nm [dB-cm ¹ ] E0M1 30 1.4 E0M2 32 0.9

Example 2

Magneto-optical modulator M0M1, M0M2 (Fig. 4, 5)

Design of the optical element

For the construction of the free-length longitudinal magneto-optical modulator M0M1. M0M2 uses less costly components. For the magneto-optically active element, the optimized MOS glass of the PbO-Bi2O3-Ga2C3 system with magnetic spinel nanoparticles with FeO, Fe2C3 and terbium trioxide TbiO2 was used. the composition of which is given in Table III. The preparation of this optical element 1 was carried out in the same manner as in Example 1.

2.1 Design of magneto-optical modulator M0M1, M0M2

The modulator M0M1, M0M2 was constructed in an aluminum box, which is produced as a die-cast aluminum alloy, and is composed of two parts (base and lid). The box lid has mounting holes for attaching it. Both parts of the box are screwed together. The box is 50 mm long, 35 mm wide and 20 mm high. A ground glass block having magneto-optical properties of 20 mm long, 1.4 mm wide and 1 mm high was inserted into the longitudinal opening of the solenoid coil 10. Custom block

A3 magneto-optical glass is fixed in the solenoid cavity by a support bed. The modulating voltage is applied to the winding 11 of the solenoid coil 10 by two leads 9 (lead wires) lead to a voltage source through the longer wall of the box.

For the M0M1 modulator, at the intersection of the longitudinal axis of the glass block in the solenoid with the shorter sides of the box, holes are drilled for the input surface 2 and the output surface 3 of the free laser beam, which is modulated by magnetic field when passing through the glass block.

For the M0M2 modulator, the laser beam inlet and outlet holes are also drilled at the intersection of the longitudinal axis of the glass block in the solenoid with the shorter sides of the box. In this case, in this case, the openings for the inlet surface 2 and the outlet surface 3 of the free laser beam are solved by gluing the glass fiber 7 by means of a fiber field (V-groove) to the inlet surface 2 of the active magneto-optical optical element 1. Due to the requirement to maintain the polarization of the optical radiation, 7 Nufem PM1950 glass fiber was chosen as suitable for a wavelength of about 2000 nm. For easy wiring to the optical system, the fiber is terminated with an FC / APC connector for connecting a pigtail laser source.

2.3 MOS glass composition for magneto-optical modulator M0M1, M0M2 and its parameters

Table III

Glass components Example 2 [wt%] PbO 35.7 BI2O3 46.2 Ga2Os 6.7 TeO ₂ - Ta ₂ O ₅ - FeO + Fe2O3 9.0 NiO - Tb ₂ O ₃ 2.4 ΡΓ2θ3 - Dy ₂ O ₃ - CoO - Sum 100.0 Melting point t _m [° C] 1025 Heat treatment temperature [° C] 490 Heat treatment time [min] 40 Stability against devitrification stable Mean nanoparticle size [nm] 70 Verdet constant V [rad T ^ m ¹ ] for wavelength 2100 nm -63 Transmittance T [%] for wavelength 2100 nm, glass thickness 1 cm 71 Refractive index n at 1311 nm 2.46 Evaluation Great

-9GB 2018 - 746 A3

The output of the optical element 1 is again free-lumped. To eliminate reflections at the interface of the individual optical environments, the fiber field and the optical glass element 1 are glued at an angle of 8 ° to each other. Alignment must be carried out on piezoelectric optic stands to ensure the lowest possible input losses. A schematic diagram of the solenoid coil 10 with active magneto-optical glass inserted is shown in Figures 4 and 5.

2.4 Testing of magneto-optical modulator M0M1, M0M2

For testing M0M1 modulator prototypes. M0M2 was created measuring set based on measurement of polarized light transmittance. To test the prototypes of these free-range modulators M0M1, M0M2, the voltage at winding 11 of the solenoid coil 10 was modulated by rectangular DC voltage pulses ranging from 0 to a maximum of 12 V in the frequency range 1 Hz to 100 GHz using a Rigol waveform generator. The effect of the applied electrical voltage on the solenoid coil 10 changed the intensity of the magnetic field, which in turn changed the refractive index of the inserted magneto-optical glass. As a result, the plane of polarized light emerging from the optical element 1 coiled, thereby changing the transmittance of the optical system as the polarizer and the analyzer rotated relative to each other. When modulating the applied voltage to the solenoid coil 10, modulators of the M0M1, M0M2 modulators modulated the intensity of the output free-time optical signal. The results of measurement of electromagnetic modulation and optical output using the Rigol oscilloscope were stored in a computer and subsequently processed. Analysis of measured response spectra of optical signal of modulator M0M1. The M0M2 recorded by the oscilloscope was determined by the response times of the optical signal of the constructed modulators. Modulators M0M1. M0M2 with optimized MOS glass from the PbO-Bi2O3-Ga2C system with spinel nanoparticles with FeO, Fe2C> 3 70 nm and terbium trioxide TbzCE in the glass element of the optical element 1 showed response times shown in Tab. IV. Response times were significantly shorter than 1 ns. The optimized MOS glass had a sufficiently high magneto-optical coefficient (characterized by a Verdet constant) and is suitable for the prototype design of the free-coupled magneto-optical modulator M0M1, M0M2 for a wavelength of 2100 nm with a fast response below 1 ns.

2.5 Parameters of electro-optical modulator M0M1, M0M2

Table IV

Modulator Response time τ [ns] Attenuation for 2100 nm [dB-cm ¹ ] M0M1 0.3 1,2 M0M2 0.4 0.7

The chosen technology of production of these modulators was verified and these developed modulators met the required characteristics. The aim and great advantage of these magnetic modulators M0M1. M0M2 is good affordability of its components. The magneto-optical glass itself contains economically advantageous components and its production, shaping and subsequent processing is not expensive. The stability of the magneto-optical glass components is very high due to the high-temperature preparation. The design of this modulator M0M1, M0M2 has also been optimized for the economy of future series production.

Industrial applicability

The developed fast electro-optical modulators E0M1, E0M2 and magneto-optical modulators M0M1. M0M2 can be used especially in intensity or phase modulation of optical signal, especially in infrared spectrum. Modulators can therefore be used

A3 in communication systems operating in the field of infrared radiation safe for the human eye. They can also be used for satellite communication. They can also be applied as sensitive magnetic field sensors or precisely controlled optical damping elements.

PATENT CLAIMS

Claims (13)

A free-light optic light modulator, in particular for an infrared region, comprising an optical element (1), characterized in that the optical element (1) (a) comprises a glass block of a PbO-Bi2O3-Ga2O glass array with optically active nano and / or microparticles that provide electro-optical or magneto-optical properties, the optically active nano and / or microparticles having a size of 0.1 nm to 50 µm, (b) having an inlet surface (2) and an outlet surface (3), both the surfaces (2, 3) are optically polished, the polished surfaces are covered with an antireflective layer, wherein the entrance surface (2) is further provided with an optical glass fiber (7), and (c) is embedded in a dielectric insulating glass material selected from glasses based on at least one of the oxides S1O2, B2O3, P2O5, V2O5, MoOs, WO3 and alkali oxides such as L12O, Na2O, K2O and Rb2O and divalent oxides like MgO, CaO, BaO and ZnO. Light modulator according to claim 1, characterized in that the optically active nano and / or microparticles have a size of 0.5 nm to 100 nm. Light modulator according to claim 1, characterized in that the optical glass fiber (7) is made of an infrared light transmissive material in the range of 1850 to 2200 nm, based on GeCE doped S1O2. Light modulator according to claim 1, characterized in that the optical glass fiber (7) is made of a material transmissive to the visible light range in the range of 460 to 700 nm, based on S102 doped with GeCh. Light modulator according to one of Claims 1 to 4, characterized in that the optical element (1) (i) is formed in the form of a longitudinal prism of the glass, with longitudinal faces (1a, 1b, 1c, 1d), namely a longitudinal lower a surface (1a) opposite the longitudinal upper surface (1b) between which opposed longitudinal side surfaces (1c, 1d) are situated; (ii) its longitudinal surfaces (1a, 1b, 1c, 1d) define oppositely located optically polished entry / exit surfaces (2, 3); and (iii) and is embedded in a dielectric insulating glass material, which is formed by a lower pad (5) and an upper cover (6). Light modulator according to one of Claims 1 to 5, characterized in that the optical element (1) is connected on its opposing side walls (1c, 1d) to electrodes (8) with leads (4), the electrodes (8) they are preferably planar. Light modulator according to one of Claims 1 to 5, characterized in that the optical element (1) is inserted into the electromagnet with the coil (10) and the coil winding (11), wherein on the coil (11) of the electromagnet coil (10) the inlets (9) are connected to an AC power source. - 11 GB 2018 - 746 A3 Light modulator according to claim 1, characterized in that the optical element (1) comprises glass carrying optically active nano and / or microparticles, which is low-melting, preferably based on lead-bismuth glass. Light modulator according to claim 1, characterized in that the optically active nano and / or microparticles are electro-optically active. Light modulator according to claim 9, characterized in that the electro-optically active nano and / or microparticles are metallic and comprise at least one metal from the group comprising Ag, Au, Pt and Cu in the form of crystalline and / or partially crystalline nano and / or metal microparticles. Light modulator according to claim 1, characterized in that the optically active nano and / or microparticles are magneto-optically active. Light modulator according to claim 11, characterized in that the magneto-optically active nano and / or microparticles are crystalline and / or partially crystalline from the group of metal oxides / oxidants, comprising magnetite Fc? and / or nickel-cobalt ferrite (NiCo) Fe2C > 4, and / or gamma-hematite Fe2C > 3, 13. The light modulator of claim 12, wherein the optical element further comprises at least one lanthanide oxide selected from the group consisting of praseodymium oxide PnCl2 and / or dyspropium oxide Dy2C3 and / or terbium oxide Tb2O3.