DE10247004A1 - Method for making polarizer involves coating sides of two transparent, trapezoidal components with transparent polymer and placing them together, forming chamber which is filled with liquid crystal material - Google Patents

Abstract

Method for making a polarizer comprises coating the largest sides of two transparent, trapezoidal components (1, 11) with a layer of transparent polymer (3, 13). These layers are placed together, forming an intermediate chamber which is filled with a liquid crystal material (F). This is oriented so that it is birefringent and produces two polarized components (K1, K2) from incident light (E). Method for making a polarizer comprises coating the largest sides of two transparent, trapezoidal components (1, 11) with a layer of transparent polymer (3, 13). These layers are placed together, forming an intermediate chamber which is filled with a liquid crystal material (F). This is oriented so that it is birefringent and produces two polarized components (K1, K2) from incident light (E). These components are orthogonally linear polarized with respect to each other, or one component is elliptically or circularly polarized, while the other is orthogonally elliptically or circularly polarized. One component is totally reflected at the boundary between the upper polymer layer and liquid crystals, while the other penetrates it. An Independent claim is included for a polarizer made by the method.

Description

Technical field:

The invention relates to a polarizer for light, with a first transparent body, which has at least a first boundary surface, and a second transparent body, which has at least a second boundary surface, and a method for producing such a polarizer.

Polarization is fundamental Property of light. Only polarized light can be in one physically uniquely characterized state; unpolarized Light is always an overlay of polarized light. Many optical components can be used for certain Applications, e.g. in optical telecommunications, can only be optimized if the polarization state of the light in the input of the optical Component is defined. In optical communication the use of polarized light is therefore desirable. Also for many Applications outside optical communication the use of polarized light is advantageous, for example in the field of material processing using laser radiation, laser welding or of laser surgery.

To polarized light from natural or to generate unpolarized light are polarizers for light necessary. Such can based on different principles, such as mirroring, on refraction or on dichroism. Especially for many applications polarization prisms are advantageous and important in practice, in which birefringent crystals are used. prisms usually consist of two birefringent prisms, between which have a non-birefringent layer. The two Prisms lie opposite each other the main areas the layer. The birefringent material from which the prisms exist, points for such unpolarized light, which determine within one Incidence angle intervals on the interface prism layer, for the ordinary Beam a different refractive index than for the extraordinary beam.

The material of the layer has one such a refractive index that the interface Prism layer either only for the normal beam the condition for total reflection is fulfilled, during the extraordinary Beam is refracted and transmitted, or vice versa. To one Total reflection of the refracted beam at the opposite layer-prism interface to avoid, the refractive index of the layer is as possible equal to the refractive index chosen for the broken one Beam is given within the primes.

A known embodiment one polarization prism is the Nicol prism; an overview of various Types of polarization prisms are e.g. in the "Handbook of Optics" by W.G. Driscoll and W. Vaughan, New York, 1978, Chapter 10, Section 7.

Significant advantages of polarization prisms across from other types of polarizers consist in the achievable high Degree of polarization and resilience with great light output. adversely is the requirement of relatively large-volume birefringent crystals to use to build the polarization prisms; these crystals are very expensive and in some desired versions Market not readily available.

Therefore polarization prisms have been developed which manage with a reduced volume of birefringent material. An example of this is the Feussner prism, which consists of two glass prisms joined together, between which there is a thin plate made of birefringent crystal. A more detailed explanation of the Feussner prism can be found, for example, in the "Handbook of Optics" by WG Driscoll and W. Vaughan, New York, 1978, Chapter 10, Section 8, pages 10-29 and 14 , given.

Despite having this type of polarizing prism associated savings of birefringent material are the mentioned Disadvantages are not complete here either eliminated. The manufacture of thin birefringent Plates is very expensive; the effort for this is further increased by the fact that the birefringent Plate with respect to the optical crystal axis in a certain direction must be cut. Furthermore, large crystals of high optical quality are required for the production of these plates Purity required. Hence the manufacture of such Polarization prisms are relatively expensive.

With the advent of nematic liquid crystals high birefringence it has become possible the thin Crystal plate of Feussner prisms through a thin layer of a nematic liquid crystal to replace; an example of this is in the publication "Polarization Prism employing an oriented Layer of a nematic liquid Crystal "by A.A. Karetnikov, published in Sov. J. Opt. Technol., V.56, pages 445-447, 1989, given.

The advantage here is that the birefringent Material is available in practically unlimited quantities at low cost, so that Polarization prisms at low cost in even very large dimensions can be produced. there remains the advantage of the very high achievable degree of polarization preserved, as in conventional polarization prisms the effect of total reflection of the ordinary or extraordinary ray is exploited.

The problem with such polarization prisms is their short lifespan, which is due to the fact that the alignment of the molecules of the Liquid crystal is not stable over the long term, ie the degree of orientation of the molecules of the liquid crystal decreases significantly over time.

It is also known to first treat a surface on which a liquid crystal is to be applied with a surface-active substance which brings about an alignment of the molecules of the liquid crystal in a preferred direction. An example of this is in the US 3991241 specified.

Furthermore, it is known to add a substance to a liquid crystal to be applied to a surface which effects or promotes an alignment of the molecules of the liquid crystal in a preferred direction. An example of this is in the US 3871904 specified.

The disadvantage in the latter two cases is that a constant Concentration of the substances mentioned cannot be achieved or cannot be achieved easily is. The consequence of this is a spatial one inhomogeneity the alignment of the liquid crystal molecules. Of more can Interactions between the substances mentioned and the liquid crystal molecules into one with time decreasing orienting effect of these substances to lead.

The invention is therefore the object based on a polarizer for To create light that is inexpensive and even in large designs can be produced with little effort, a high degree of polarization achieved, has a long service life and largely homogeneous Polarization properties possible even over large areas.

• a) die erste Begrenzungsfläche des ersten Körpers wird mit einer ersten transparenten Polymerschicht und die zweite Begrenzungsfläche des zweiten Körpers mit einer zweiten transparenten Polymerschicht beschichtet, welche so beschaffen sind, daß Licht, dessen Einfallswinkel auf die erste oder zweite Begrenzungsfläche innerhalb eines bestimmten Winkelintervalls liegt, weder an der ersten noch an der zweiten Begrenzungsfläche totalreflektiert wird,
• b) die beiden Körper werden zueinander so angeordnet, daß die erste und die zweite Polymerschicht einander im wesentlichen gegenüberliegend zugewandt und unter Bildung eines Zwischenraumes voneinander beabstandet sind,
• c) der Zwischenraum wird mit einem transparenten Flüssigkristall gefüllt, so daß dieser mit der ersten und mit der zweiten Polymerschicht in Berührungskontakt steht, wobei der Flüssigkristall so ausgebildet ist, daß die Moleküle des Flüssigkristalls aufgrund des Berührungskontaktes desselben mit den Polymerschichten im Mittel in eine bestimmte Vorzugsrichtung ausgerichtet werden und der Flüssigkristall hierdurch in solcher Weise doppelbrechend wird, daß unpolarisiertes Licht, dessen Einfallswinkel auf die erste oder zweite Begrenzungsfläche innerhalb des bestimmten Winkelintervalls liegt, an der Grenzfläche zwischen der ersten oder zweiten Polymerschicht und dem Flüssigkristall in eine erste und eine zweite polarisiere Komponente aufgespalten wird, wobei – entweder die erste und die zweite Komponente orthogonal zueinander linear polarisiert sind, – oder die erste Komponente elliptisch bzw. zirkular polarisiert und die zweite Komponente zur ersten Komponente orthogonal elliptisch bzw. orthogonal zirkular polarisiert ist, – und die erste Komponente an der Grenzfläche zwischen der ersten oder zweiten Polymerschicht und dem Flüssigkristall im wesentlichen totalreflektiert wird und die zweite Komponente im wesentlichen vom ersten Körper durch den Flüssigkristall hindurch in den zweiten Körper übergeht, wobei mindestens eine der Komponenten als polarisiertes Licht aus dem ersten oder zweiten Körper austritt.

This object is achieved according to the invention by a method for producing a polarizer for light, using a first transparent body which has at least one first boundary surface and a second transparent body which has at least a second boundary surface, characterized by the following steps:

• a) the first boundary surface of the first body is coated with a first transparent polymer layer and the second boundary surface of the second body is coated with a second transparent polymer layer, which are designed so that light whose angle of incidence on the first or second boundary surface lies within a certain angular interval, there is no total reflection on either the first or the second boundary surface,
• b) the two bodies are arranged with respect to one another in such a way that the first and second polymer layers face one another essentially opposite one another and are spaced apart from one another to form an intermediate space,
• c) the intermediate space is filled with a transparent liquid crystal, so that it is in contact with the first and with the second polymer layer, the liquid crystal being designed such that the molecules of the liquid crystal, on account of the contact thereof with the polymer layers, average in a certain one Preferred direction are aligned and the liquid crystal thereby becomes birefringent in such a way that unpolarized light, the angle of incidence of which on the first or second boundary surface lies within the specific angular interval, polarizes into a first and a second at the interface between the first or second polymer layer and the liquid crystal Component is split, whereby - either the first and the second component are linearly polarized orthogonally to each other, - or the first component is elliptically or circularly polarized and the second component is orthogonal to the first component is elliptically or orthogonally circularly polarized, - and the first component at the interface between the first or second polymer layer and the liquid crystal is substantially totally reflected and the second component essentially passes from the first body through the liquid crystal into the second body, at least one of the components emerges as polarized light from the first or second body.

• a) die erste Begrenzungsfläche des ersten Körpers mit einer ersten transparenten Polymerschicht und die zweite Begrenzungsfläche des zweiten Körpers mit einer zweiten transparenten Polymerschicht beschichtet sind, welche Polymerschichten so beschaffen sind, daß Licht, dessen Einfallswinkel auf die erste oder zweite Begrenzungsfläche innerhalb eines bestimmten Winkelintervalls liegt, weder an der ersten noch an der zweiten Begrenzungsfläche totalreflektiert wird,
• b) die beiden Körper zueinander so angeordnet sind, daß die erste und die zweite Polymerschicht einander im wesentlichen gegenüberliegend zugewandt und unter Bildung eines Zwischenraumes voneinander beabstandet sind, welcher mit einem transparenten Flüssigkristall gefüllt ist, der somit mit der ersten und mit der zweiten Polymerschicht in Berührungskontakt steht,
• c) die erste und die zweite Polymerschicht sowie der Flüssigkristall so beschaffen sind, daß die Moleküle des Flüssigkristalls aufgrund des Berührungskontaktes desselben mit den Polymerschichten im Mittel in eine bestimmte Vorzugsrichtung ausgerichtet sind, und
• d) der Flüssigkristall hierdurch in solcher Weise doppelbrechend ist, daß unpolarisiertes Licht, dessen Einfallswinkel auf die erste oder zweite Begrenzungsfläche innerhalb des bestimmten Winkelintervalls liegt, an der Grenzfläche zwischen der ersten oder zweiten Polymerschicht und dem Flüssigkristall in eine erste und eine zweite polarisierte Komponente aufgespalten wird, wobei – entweder die erste und die zweite Komponente orthogonal zueinander linear polarisiert sind, – oder die erste Komponente elliptisch bzw. zirkular polarisiert und die zweite Komponente zur ersten Komponente orthogonal elliptisch bzw. orthogonal zirkular polarisiert ist, – und die erste Komponente an der Grenzfläche zwischen der ersten oder zweiten Polymerschicht und dem Flüssigkristall im wesentlichen totalreflektiert wird und die zweite Komponente im wesentlichen vom ersten Körper durch den Flüssigkristall hindurch in den zweiten Körper übergeht, wobei mindestens eine der Komponenten als polarisiertes Licht aus dem ersten oder zweiten Körper austritt.

The object is further achieved by a polarizer for light, having a first transparent body which has at least one first boundary surface and a second transparent body which has at least one second boundary surface, characterized in that

• a) the first boundary surface of the first body with a first transparent polymer layer and the second boundary surface of the second body with a second transparent polymer layer are coated, which polymer layers are such that light, the angle of incidence of the first or second boundary surface is within a certain angular interval , there is no total reflection on either the first or the second boundary surface,
• b) the two bodies are arranged with respect to one another such that the first and the second polymer layer face each other substantially opposite each other and are spaced apart to form an intermediate space which is filled with a transparent liquid crystal, which is thus in contact with the first and with the second polymer layer Is in touch,
• c) the first and second polymer layers and the liquid crystal are such that the molecules of the liquid crystal due to the contact thereof with the polymer layers are aligned in a certain preferred direction, and
• d) the liquid crystal is thus birefringent in such a way that unpolarized light, the angle of incidence of which on the first or second boundary surface lies within the specific angular interval, is split into a first and a second polarized component at the interface between the first or second polymer layer and the liquid crystal is, - either the first and the second component are linearly polarized orthogonally to one another, - or the first component is elliptically or circularly polarized and the second component is orthogonally elliptically or orthogonally circularly polarized to the first component, - and the first component at the Interface between the first or second polymer layer and the liquid crystal is substantially totally reflected and the second component essentially passes from the first body through the liquid crystal into the second body, at least one of the components being polar isolated light emerges from the first or second body.

• a1) der erste bzw. zweite Körper wird in eine Beschichtungskammer verbracht, welche ein Kohlenwasserstoff-Monomer in gasförmigem Zustand enthält,
• a2) in der Beschichtungskammer wird ein elektrisches Feld erzeugt, indem zwischen einer ersten Elektrode und einer von dieser beabstandeten zweiten Elektrode eine elektrische Spannung angelegt wird,
• a3) der erste bzw. zweite Körper wird innerhalb der Beschichtungskammer so angeordnet, daß sich mindestens ein Teil der ersten bzw. zweiten Begrenzungsfläche (2,12) in dem elektrischen Feld befindet,
• a4) die elektrische Spannung wird so gewählt, daß durch dieselbe zwischen den Elektroden eine Gasentladung ausgelöst wird, welche zu einem Strom von Ionen des Kohlenwasserstoff-Monomers in Richtung der ersten bzw. zweiten Begrenzungsfläche und dort zu einer Anlagerung und Polymerisation der Ionen führt, so daß auf der ersten bzw. zweiten Begrenzungsfläche eine Schicht eines Kohlenwasserstoff-Polymers, nämlich die erste bzw. zweite Polymerschicht, gebildet wird.

According to a preferred variant of the method according to the invention, method step a) comprises the following substeps:

• a1) the first or second body is placed in a coating chamber which contains a hydrocarbon monomer in the gaseous state,
• a2) an electrical field is generated in the coating chamber by applying an electrical voltage between a first electrode and a second electrode spaced apart therefrom,
• a3) the first or second body is arranged within the coating chamber in such a way that at least part of the first or second boundary surface ( 2 . 12 ) is in the electric field,
• a4) the electrical voltage is selected so that it causes a gas discharge between the electrodes, which leads to a flow of ions of the hydrocarbon monomer in the direction of the first or second boundary surface and there to an accumulation and polymerization of the ions, so that a layer of a hydrocarbon polymer, namely the first or second polymer layer, is formed on the first or second boundary surface.

• a1) der erste bzw. zweite Körper wird in eine Beschichtungskammer verbracht, welche ein Kohlenwasserstoff-Monomer in gasförmigem Zustand enthält,
• a2) in der Beschichtungskammer wird ein elektrisches Feld erzeugt, indem zwischen einer ersten Elektrode und einer von dieser beabstandeten zweiten Elektrode eine elektrische Spannung angelegt wird,
• a3) der erste bzw. zweite Körper wird innerhalb der Beschichtungskammer so angeordnet, daß sich mindestens ein Teil der ersten bzw. zweiten Begrenzungsfläche in dem elektrischen Feld befindet,
• a4) die elektrische Spannung wird so gewählt, daß durch dieselbe zwischen den Elektroden eine Gasentladung ausgelöst wird, welche zu einem Strom von Ionen des Kohlenwasserstoff-Monomers in Richtung der ersten bzw. zweiten Begrenzungsfläche und dort zu einer Anlagerung und Polymerisation der Ionen führt, so daß auf der ersten bzw. zweiten Begrenzungsfläche eine Schicht eines Kohlenwasserstoff-Polymers, nämlich die erste bzw. zweite Polymerschicht, gebildet wird.

According to a preferred embodiment, a polarizer according to the invention is therefore characterized in that the first and second polymer layers are produced as follows:

• a1) the first or second body is placed in a coating chamber which contains a hydrocarbon monomer in the gaseous state,
• a2) an electrical field is generated in the coating chamber by applying an electrical voltage between a first electrode and a second electrode spaced apart therefrom,
• a3) the first or second body is arranged within the coating chamber in such a way that at least part of the first or second boundary surface is in the electric field,
• a4) the electrical voltage is selected so that it causes a gas discharge between the electrodes, which leads to a flow of ions of the hydrocarbon monomer in the direction of the first or second boundary surface and there to an accumulation and polymerization of the ions, so that a layer of a hydrocarbon polymer, namely the first or second polymer layer, is formed on the first or second boundary surface.

As the hydrocarbon monomer, a saturated hydrocarbon monomer or an aliphatic hydrocarbon monomer can be used. In particular, a monomer of octane C ₈ H ₁₈ can be used as the hydrocarbon monomer.

The partial pressure is preferred of the hydrocarbon monomer in the coating chamber between 0.1 and 0.3 Pa selected.

Before executing sub-step a4) the coating chamber is preferably evacuated and then the Hydrocarbon monomer introduced into the coating chamber, So that the Coating chamber during the execution of sub-step a4) contains essentially no gas other than the hydrocarbon monomer.

The amount of electrical voltage is preferably chosen between 1300 and 2000 volts. The Voltage can be a DC voltage or an AC voltage, in particular be a high frequency AC voltage.

The pressure inside is preferred the coating chamber and the electrical voltage selected so that the gas discharge takes place as a glow discharge.

According to a preferred, particularly advantageous embodiment of the invention, the first or second boundary surface is oriented during the execution of sub-step a4) such that when the first boundary surface is coated, a first edge region of the first boundary surface of the first electrode and a second edge region of the first boundary surface of the is facing the second electrode, and in coating the second boundary surface a first edge region of the second boundary surface of the first electrode and a The second edge area of the second boundary surface faces the second electrode, the amount of the angle β between the normal of the first boundary surface and the central direction of the field lines of the electric field being between 80 ° and 100 °, preferably between 85 ° and 95 °.

According to a refinement of this The first or second boundary surface during the configuration execution of sub-step a4) so that the amount of the angle β between the normals of the first and second boundary surfaces and the mean direction of the field lines of the electric field between 87 ° and 89 ° or between 91 ° and Is 93 °. Preferably for at the coating of the first and the coating of the second boundary surface the angle β is identical selected.

According to another particularly advantageous embodiment of the invention is in the process step b) the first edge region of the first boundary surface second edge area opposite the second boundary surface and the second edge area the first boundary surface arranged opposite the first edge region of the second boundary surface.

To produce the polarizer, the liquid crystal is preferably filled into the intermediate space, the bodies being oriented such that the solder forms an angle δ on the first and / or the second boundary surface with the horizontal, which is given by δ = 90 ° -β , According to a preferred variant of the invention, the bodies are therefore oriented before executing method step c) such that the solder L forms an angle with the horizontal on the first and / or the second boundary surface δ includes which is given by δ = 90 ° -β and which is kept substantially constant during the filling of the liquid crystal into the space.

According to a preferred embodiment of the Invention are the first and second boundary surfaces, respectively flat surfaces; such an execution is not mandatory, however; rather, the boundary surfaces or one of them also curved his.

Furthermore, according to a preferred embodiment In the invention, the first and second bodies each have prisms so that the polarizer is a polarizing prism. Therefore, first and first are preferred as a second body each a prismatic body used so that first and second boundary surfaces are each flat surfaces.

The first and second boundary surfaces will be in method step b) preferably aligned parallel to one another According to one preferred embodiment of a polarizer according to the invention the first and second boundary surfaces are therefore parallel aligned with each other, i.e. the expansion of the space perpendicular to the boundary surfaces is constant.

Are preferred as the first and as second body each a vitreous used so the first and the second body each made of glass and therefore made of inexpensive material.

According to a preferred variant The invention method is at least between the boundary surface a spacer is arranged, which the two bodies in their mutual position fixed or is able to fix. Preferably, three identical spacers are used, which are arranged in a triangle. The spacer or spacers can each with both boundary surfaces glued or welded be and thus the two bodies fix together. The spacers can e.g. are made of Teflon.

To escape the liquid crystal To prevent from the gap can be between the boundary surfaces Sealing material should be introduced so that the gap is completely closed will, i.e. the intermediate space is through on its main surfaces the polymer layers, on its narrow sides through the sealing material locked. For filling of the liquid crystal can leave a small hole or in the sealing material or drilled into one of the spacers. Of course you can the sealing material at the same time as peripheral around the space circumferential ring-shaped spacer serve.

As the liquid crystal is preferred one uses its molecules due to the touch contact of the liquid crystal aligned homeotropically with the polymer layers become. In particular, can be used as a liquid crystal a smectic or a nematic liquid crystal can be used.

A can also be used as the liquid crystal nematic liquid crystal be used, its molecules due to the touch contact of the liquid crystal with the polymer layers aligned on average perpendicular to the boundary surfaces become.

The mutual position of the body will preferably, when using spacers e.g. by appropriate Choice of the dimensions of the same, chosen so that the expansion of the space in the to the boundary surfaces vertical direction, i.e. towards the solder on the boundary surfaces, between 400 nm and 50 μm. According to one Refinement of this variant is the mutual position of the body chosen that extension of the space in the direction perpendicular to the boundary surfaces is 20 μm to 50 μm. The The thickness of the polymer layers is preferably in each case between 50 nm and 100 μm.

The selection of the material for the transparent body and the liquid crystal is preferred according to the spectral range in which the se materials are transparent, and the refractive indices of these materials. For example, for a liquid crystal with an optical anisotropy of the refractive indices between 0.1 and 0.3, and in the case where the refractive index of the material of the transparent bodies is approximately equal to the refractive index for the ordinary ray, the above-mentioned one determines Angular interval of the angle of incidence, which leads to the total reflection of one of the components, is between 60 ° and 70 °.

By the method according to the invention is the production of a homogeneous liquid crystal layer without dislocations and other defects as well as with long-term stability in a preferred direction aligned molecules allows. A using such a liquid crystal layer manufactured polarizer according to the invention the advantages of low material costs, a high degree of polarization, a big one possible aperture, a long service life and a simple, easily automatable Manufacturability. For coating the boundary surfaces with Polymer layers can conventional vacuum systems to be used. Polarizers according to the invention can can therefore be manufactured industrially in a simple manner and leave very advantageous in optical communication and use information processing.

Brief description of the drawing, in which schematically show:

1 2 shows a side view of a polarizer according to the invention with two prism-shaped glass bodies, between which there are spacers, two polymer layers and between them a liquid crystal layer, the thickness of the polymer layers and the liquid crystal layer being greatly exaggerated for reasons of clarity,

2 an application example of the polarizer from 1 in an optical communication system, with the polarizer opposite 1 is shown reduced and the spacers, the polymer layers and the liquid crystal layer are omitted,

3 a cross-sectional view of a coating chamber in which there are two electrodes, one of the vitreous 1 as well as a gaseous hydrocarbon monomer, the glass body opposite 1 is shown reduced in size and an electrical direct voltage is applied between the electrodes,

4 the polarizer of 1 during the filling of the liquid crystal into the space between the polymer layers,

5 a time diagram α _S / α _P ratio for different bonds within the molecules of the liquid crystal, which with the polymer layers of 1 is in touch, and

6 a cracked section of one of the vitreous 1 with an applied polymer layer in perspective with some extremely enlarged and symbolically represented molecules of a nematic liquid crystal, which is covered with both polymer layers from 1 is in contact, whereby the molecules are aligned parallel to one another and perpendicular to the polymer layer.

The 1 to 6 each relate to a preferred variant of the invention.

1 shows a schematic side view of a polarizer according to the invention for light, which has two glass prisms 1 . 11 includes. The first glass prism 1 has a first flat boundary surface 2 on which the second glass prism 11 is facing. The second glass prism also points 11 a second flat boundary surface 12 on which the first glass prism 1 is facing. The glass from which the two glass prisms are made 1 . 11 exist, is not birefringent, ie it is optically isotropic, and has a refractive index of typically, for example, 1.68. The prism angle is typically 70 °, for example. Both are preferably glass prisms 1 . 11 of identical construction.

The first boundary surface 2 of the first glass prism 1 is with a first transparent polymer layer 3 coated. The second boundary surface is also 12 of the second glass prism 11 with a second transparent polymer layer 13 coated.

Using two spacers 4 . 5 are the two glass prisms 4 . 5 fixed in their mutual position so that the first and second boundary surfaces 2 . 12 facing each other and spaced parallel to form an intermediate space.

The polymer layers 3 . 13 are such that light, whose angle of incidence φ on the first boundary surface 2 is within a certain angular interval, neither on the first nor on the second boundary surface 2 . 12 is totally reflected. The two polymer layers 3 . 13 have a constant thickness over their entire area, which in 1 is greatly exaggerated for reasons of clarity and clarity and is typically between 50 nm and 100 μm in practice. The thickness of the polymer layers is preferred 3 . 13 each chosen smaller than a wavelength of the light to be polarized, so that the refractive index of the polymer layers 3 . 13 is insignificant for the transmission and polarization properties of the polarizer.

The space between the polymer layers 3 . 13 is filled with a transparent nematic liquid crystal F, which is thus with the first and with the second polymer layer 3 . 13 is in touch contact. Because of this touch The molecules of the nematic liquid crystal F are in contact with the polymer layers 3 . 13 interacting. The expansion of the intermediate space in the direction of the solder L is preferably between 400 nm and 50 μm, typically for example 10 μm.

The first and second polymer layers 3 . 13 and the nematic liquid crystal F are such that the molecules of the nematic liquid crystal F are on average in a certain preferred direction due to this interaction, namely perpendicular to the boundary surfaces 2 . 12 or homootropic, and the liquid crystal F thereby becomes birefringent in such a way that unpolarized light E, which lies through the first glass prism under one of the specified angular intervals, onto the first boundary surface 2 occurs at the interface between the first polymer layer 3 and the nematic liquid crystal F is split into a first and a second polarized component K1, K2, which are linearly polarized orthogonally to one another. The angle of incidence φ is the angle between the direction of the incident unpolarized light E and the solder L on the boundary surfaces 2 . 12 Are defined. The preferred direction is in 1 marked as Z-direction.

The polymer layers 3 . 13 thus serve for alignment, ie for orienting the molecules in a certain preferred direction, which is also referred to as "director" and in the present example runs approximately parallel to the perpendicular L. The polymer layers 3 . 13 can therefore also be called "orientation layers".

Because the glass from which the two glass prisms 1 . 11 exist, is not birefringent, the glass has the same refractive index for both components K1, K2. The nematic liquid crystal F is such that the refractive index of the nematic liquid crystal for the first component K1 is smaller than the refractive index of the glass from which the two glass prisms are made 1 . 11 exist, and the first component K1 at the interface between the first polymer layer 3 and the nematic liquid crystal F is totally reflected, and the refractive index of the nematic liquid crystal for the second component K2 is equal to or approximately equal to the refractive index of the glass, so that the second component K2 is not totally reflected, but with material-related reflection and absorption losses from the first glass prism 1 through the nematic liquid crystal F into the second glass prism 11 transforms.

The determined angular interval, within which the angle of incidence φ must lie, by total reflection of the first component K1 at the boundary layer between the first polymer layer 3 and to enable the nematic liquid crystal F can typically be, for example, between 60 ° and 70 °. Depending on the choice of the material used as liquid crystal F, the ordinary beam as the first component K1 can be totally reflected at the boundary layer mentioned and the extraordinary beam can be transmitted or vice versa. The difference in the refractive indices of the nematic liquid crystal F for the two components K1, K2 is typically Δn = 0.1 ... 0.3.

The first component K1 emerges as linearly polarized light from the first glass prism 1 , the second component K2 as orthogonally polarized light from the second glass prism 11 out. Of course, one of the components K1, K2 can be made, for example, by blackening or covering the light exit surface of the glass prism in question 1 respectively. 11 are filtered out so that only one of the linearly polarized components K1 or K2 can leave the polarizer.

Between the boundary surfaces 2 . 12 is a sealing material, not shown, introduced so that the space is completely closed and the nematic liquid crystal F can not escape from the space.

The first boundary surface 2 has a first edge region 6 and a second edge area 7 on which the first edge area 6 on the first boundary surface 2 is substantially diametrically opposite and from this in a direction perpendicular to the Z direction, in 1 marked as X direction, is spaced. The second boundary surface also points 12 a first edge area 16 and second edge area 17 on which the first edge area 16 on the second boundary surface 12 is substantially diametrically opposite and spaced from it in the X direction. The two boundary surfaces 2 . 12 of 1 lie opposite each other to form the intermediate space so that the first edge region 6 the first boundary surface 2 the second edge area 17 the second boundary surface 12 opposite and the second edge area 7 the first boundary surface 2 the first edge area 16 the second boundary surface 12 is arranged opposite; this is referred to below with reference to 3 discussed in more detail.

The usable spectral range of a polarizer according to the invention, which has no substantial Fresnel loss is essentially determined through the transmission of the glass prisms and the liquid crystal layer.

6 schematically shows a section of the second glass prism shown in a crack 11 of 1 with the polymer layer applied to it 13 in perspective with some extremely enlarged and symbolically shown cyanobiphenyl molecules M of a nematic liquid crystal, which with both polymer layers 3 . 13 of 1 is in contact, whereby the molecules M parallel to each other and almost perpendicular or homeotropic to the polymer layers 3 . 13 are aligned; the direction of the solder on the polymer layer 13 is in 6 marked as Z-direction and corresponds to the Z-direction of 1 , The first glass prism 1 as well as the first polymer layer 3 of 1 are in 6 not shown. The liquid crystal usually consists of a mixture of different molecules.

The direction of orientation of the liquid crystal molecules M homeotropic or almost perpendicular to the surface of the polymer layers 3 . 13 is due to the interaction of the nematic liquid crystal molecules M with the surface molecules of the polymer layers 3 . 13 as well as determined by hydrogen bonds.

2 shows schematically an application example of the polarizer of 1 in an optical communication system, with the polarizer opposite 1 is shown reduced and the spacers 4 . 5 , the polymer layers 3 . 13 and the liquid crystal layer F of 1 are omitted for the sake of clarity. An unpolarized optical signal passes through an optical coupling lens via an optical fiber F0 30 into the first glass prism 1 , wherein the angle of incidence lies within the specific angular interval explained above. Because of the optical fiber F0 in the first glass prism 1 Incident light E is split by the polarizer into two components K1, K2 which are linearly polarized perpendicular to one another, as above with reference to FIG 1 explained.

The first component K1 emerges from the first glass prism after total reflection 1 and is for further processing or use by a coupling-out lens 31 fed into an optical fiber F1. Likewise, the second component K2 which is linearly polarized perpendicular to the first component K1 becomes after passing through the liquid crystal F and through the second glass prism 11 out of this through a coupling lens 32 uncoupled and fed into an optical fiber F2 for further processing or use.

3 serves to illustrate a variant of the production of the polymer layers according to the invention 3 . 13 of 1 and shows a schematic cross-sectional view of a coating chamber 20 , in which there are two electrodes 21 . 22 and a gaseous hydrocarbon monomer, not shown. In the coating chamber 20 there is also the first glass prism 1 of 1 for the purpose of coating the first boundary surface 2 with the first polymer layer 3 ( 1 ), what a 3 does not yet exist. The glass prism 1 is in 3 across from 1 shown reduced.

In the coating chamber 20 becomes an electric field 23 generated by between the first of the second electrode spaced therefrom 22 an electrical voltage is applied, which in the example of 3 is a DC voltage. The polarity of the DC voltage is in the example of 3 chosen so that the first electrode 21 a cathode and the second electrode 22 is an anode. The electrodes 21 . 22 do not necessarily have to be plate-shaped.

The first glass prism 1 is in the coating chamber 20 arranged so that the first boundary surface 2 in the electric field 23 located. The one between the electrodes 21 and 22 applied electrical voltage is chosen so that it between the two electrodes 21 . 22 a gas discharge is triggered, resulting in a flow of gaseous ions in the coating chamber 20 hydrocarbon monomer present in the direction of the first boundary surface 2 and there leads to an accumulation and polymerization of the ions. This way, the first boundary surface 2 a layer of a hydrocarbon polymer, namely the first polymer layer 3 educated.

Before applying the electrical voltage, the coating chamber 20 first evacuated; then the hydrocarbon monomer is fed into the coating chamber 20 introduced so that the coating chamber 20 contains essentially no gas other than the hydrocarbon monomer. The partial pressure of the hydrocarbon monomer in the coating chamber 20 is preferably between 0.1 and 0.3 Pa.

The amount of electrical voltage is typically between 1300 and 2000 volts and is preferably chosen so that the gas discharge in the coating chamber 20 takes place as a glow discharge.

The first boundary surface 2 is inside the coating chamber 20 oriented in such a way that when coating the first boundary surface 2 the first edge area 6 ( 1 ) of the first electrode or cathode 21 and the second edge area 7 the first boundary surface 2 the second electrode or anode 22 is facing. The amount of the angle β between the perpendicular L on the first boundary surface 1 and the mean direction of the field lines 23 The electric field is preferably between 87 ° and 89 °, so that the ions of the hydrocarbon monomer graze the first boundary surface 2 incident.

For the production of the second polymer layer 13 on the second boundary surface 3 the procedure is completely analogous to this (not shown). The second glass prism 2 is in the coating chamber 20 so arranged that the second boundary surface 2 in the electric field 23 is located, the first edge area 16 the second boundary surface 12 the cathode 21 and the second edge area 17 the second boundary surface 12 the anode 22 is facing and the amount of the angle β between the perpendicular L to the second boundary surface 12 and the mean direction of the field lines 23 is preferably again between 87 ° and 89 ° so that the ions of the hydrocarbon monomer also on the second boundary surface 12 hit with grazing incidence; this geometry has been used to achieve the desired ability of the polymer layers to remove the molecules of the nematic liquid crystal F ( 1 ) by touching it essentially perpendicular to the boundary surfaces 2 . 12 align, proven to be particularly advantageous.

The electrical voltage is used to coat the second boundary surface 12 with unchanged polarity again preferably chosen so that between the two electrodes 21 . 22 a glow discharge is triggered, resulting in a flow of gaseous ions in the coating chamber 20 hydrocarbon monomer present towards the second boundary surface 21 and there leads to an accumulation and polymerization of the ions, whereby the second polymer layer 13 is formed. The hydrocarbon-monomer partial pressure is again preferably chosen between 0.1 and 0.3 Pa.

The thickness of the polymer layers so formed 3 . 13 is essentially proportional to the time over which the glow discharge is maintained and can therefore be controlled in a wide range. Typically, the process is controlled so that approximately 100 nm thick polymer layers are produced. The refractive index of the polymer layers produced in this way is typically approximately 1.5 with an extinction coefficient in the visible and near infrared spectral range of typically approximately 0.01 to 0.02.

The coatings of the boundary surfaces 2 . 12 are preferably carried out one after the other; alternatively can with sufficient spatial expansion of the electric field 23 both boundary surfaces 2 . 12 be coated at the same time.

After coating, the two boundary surfaces 2 . 12 arranged opposite each other so that the first edge region 6 the first boundary surface 2 the second edge area 17 the second boundary surface 12 opposite and the second edge area 7 the first boundary surface 2 the first edge area 16 the second boundary surface 12 is arranged opposite, ie the first edge region 6 the first boundary surface 2 which, when coating the cathode 21 facing the second edge area 17 the second boundary surface 12 which when coating the anode 22 was facing, arranged opposite. In this way it is ensured according to the invention that the hydrocarbon polymers formed during the coating of both polymer layers 3 . 13 are aligned in the antiparallel preferred direction and thus collinear. It has been found that this results in the orienting effect of the polymer layers 3 . 13 on the liquid crystal F ( 1 ) significantly improved, intensified and homogenized and the lifespan of this effect is extended considerably.

According to another variant of the invention, the polarity of the DC electrical voltage is opposite 3 unchanged orientation of the boundary surfaces 2 . 12 interchanged so that the first electrode 21 the anode and the second electrode 22 is the cathode. According to a further variant of the invention, the electrical voltage is opposite 3 unchanged orientation of the boundary surfaces 22 . 12 an AC voltage; in particular, it can be an HF alternating voltage.

After the glass prisms are arranged relative to one another in the manner mentioned, the intermediate space is closed all around by a sealing material, for example epoxy resin. The mutual fixation of the two glass prisms 1 . 11 can first be joined together using spacers 4 . 5 take place and are finally stabilized by the sealing material. The liquid crystal F can then be filled into the intermediate space. Here, the two boundary surfaces 2 . 12 preferably oriented in a certain direction with respect to the direction of gravity, which is explained below with reference to 4 is explained.

4 shows the polarizer of 1 in cross-sectional view during the filling of the liquid crystal F in the space 50 between the polymer layers 3 . 13 according to a preferred variant of the method according to the invention. The expansion of the space 50 perpendicular to the boundary surfaces 2 . 12 is in 4 for the sake of clarity 1 shown enlarged. 4 refers to a point in time at which part of the space already exists 50 is filled with the liquid crystal so that the liquid crystal F has a surface S located in the intermediate space at the top; this represents the liquid level of the liquid crystal F and runs on average horizontally, ie perpendicular to gravity, and of course increases with an increasing amount of the liquid crystal F. The spacer 5 has a bore through which the liquid crystal F can be filled into the space, for example with the aid of a cannula; this process is in 4 symbolized by an arrow P.

The liquid crystal can in particular in the isotropic state under the action of capillary forces. At the transition the liquid crystal molecules go out into the nematic phase from the surface of the polymer layers and progressing into the interior of the liquid crystal aligned

While filling the liquid crystal F into the space 50 are the glass prisms 1 . 11 preferably oriented so that the solder L on the boundary surfaces 2 . 12 with the central direction of the surface S of the liquid crystal F, ie with that in 4 Horizontal lines shown in dash-dot lines includes an angle δ, which is given by δ = β-90 °, where β is the angle between the perpendicular L on the boundary surfaces 2 . 12 and the mean direction of the field lines 23 of the electric field of 3 is. It has been found that this procedure achieves the desired orienting effect of the polymer layers 3 . 13 on the liquid crystal F further improved, intensified, homogenized, stabilized and their lifespan is extended.

The deviation of the director of the orientation of the liquid crystal molecule M from the direction of the solder L on the polymer layers 3 . 13 is in the manufacture of the polymer layers according to that with reference to 3 and 4 explained procedure low, namely typically less than 3 °.

5 shows a time chart of measured values of the dichroic ratio α _S / α _{P of} the vibration absorption bands in the infrared for various bonds within the molecules of the cyanobiphenyl-based liquid crystal, which consists of molecules, some of which in 6 are exemplified as molecules M, and which with the polymer layers produced according to the invention by glow discharge from an octane vapor 3 . 13 of 1 is in contact, whereby the molecules M perpendicular to the polymer layers 3 . 13 be aligned. The ratio α _S / α _P is a measure of the birefringence of the liquid crystal and thus also a measure of the degree of orientation of the molecules M. With triangles are in 5 the to the in 6 marked C≡N triple bond within the molecules M with the reference symbol B1, with squares the measured values which correspond to the in 6 CC bond marked with the reference symbol B2 within a phenyl ring, and with filled circles the measured values which correspond to that in 6 CC bonds marked with the reference symbol B3 belong between the phenyl rings.

The time t1 denotes in 5 the instant immediately after the manufacture of a polarizer according to the invention with reference to 3 and 4 explained way. The time t2 marks a time approximately 10 months after the time t1. Out 5 it can be seen that within 10 months after the manufacture of the polarizer according to the invention the ratio α _S / α _{P has} risen only slightly and thus the birefringent properties of the liquid crystal F and thus also its polarization properties have changed only slightly; the lifetime of the alignment of the molecules M of the liquid crystal produced according to the invention is very long. The increase in the ratio α _S / α _P between times t1 and t2 is due to the absorption of hydroxyl groups on the surface of the polymer layers 3 . 13 and caused by the formation of hydrogen bonds.

The time t3 denotes in 5 a point in time immediately after heating the liquid crystal to 65 ° C and cooling it again. A nematic-isotropic-nematic transition was triggered by the heating; the ratio α _S / α _P then returned to its original value at the time t1. By measuring the wetting angle it was shown that the surface energy of the polymer layers was approximately 38 mJ / m ² .

Industrial applicability:

The invention can be advantageous in the optical communication and information processing and for the production of corresponding components deploy.

1.11

First, second transparent body

2.12

first, second boundary surface

3.13

first, second polymer layer

4.5

spacer

6.7

first, second edge area of 2

16.17

first, second edge area of 12

20

coating chamber

21.22

first, second electrode

23

electrical field lines

24.25

electrical cables

30,31,32

converging lenses

50

Space between 3 and 13

B1, B2, B3

bonds in m

e

incident unpolarized light

F

liquid crystal

F0, F1, F2

optical fibers

K1, K2

first, second component

L

Solder on 2 . 12

M

Molecules from F

P

Arrow in 4

S

liquid level from F

β

Angle between 23 and L

δ

angle between S and L.

φ

angle of incidence from E

Claims (49)

Method for producing a polarizer for light, using a first transparent body ( 1 ), which has at least a first boundary surface ( 2 ) and a second transparent body ( 11 ), which has at least a second boundary surface ( 12 ), characterized by the following steps: a) the first boundary surface ( 2 ) of the first body ( 1 ) with a first transparent polymer layer ( 3 ) and the second boundary surface ( 12 ) of the second body ( 11 ) with a second transparent polymer layer ( 13 ) coated, which are such that light, the angle of incidence (φ) of the first or second boundary surface ( 2 . 12 ) lies within a certain angular interval, neither on the first nor on the second boundary surface ( 2 . 12 ) is totally reflected, b) the two bodies ( 1 . 11 ) are arranged in relation to each other in such a way that the first and the second polymer layer ( 3 . 13 ) facing each other essentially opposite each other and forming a space ( 50 ) are spaced from each other, c) the space ( 50 ) is filled with a transparent liquid crystal (F), so that this with the first and with the second polymer layer ( 3 . 13 ) is in touch contact, the liquid crystal (F) being designed in such a way that the molecules (M) of the liquid crystal (F) due to the touch contact thereof with the polymer layers ( 3 . 13 ) are aligned on average in a certain preferred direction and the liquid crystal (F) thereby becomes birefringent in such a way that unpolarized light (E), its angle of incidence (φ) on the first or second boundary surface ( 2 . 12 ) lies within the determined angular interval, at the interface between the first or second polymer layer ( 3 . 13 ) and the liquid crystal (F) is split into a first and a second polarized component (K1, K2), wherein - either the first and the second component (K1, K2) are linearly polarized orthogonally to one another, - or the first component (K1 ) is elliptically or circularly polarized and the second component (K2) is orthogonally elliptically or orthogonally circularly polarized to the first component (K1), - and the first component (K1) at the interface between the first or second polymer layer ( 3 . 13 ) and the liquid crystal (F) is essentially totally reflected and the second component (K2) essentially from the first body ( 1 ) through the liquid crystal (F) into the second body ( 11 ) passes, at least one of the components (K1, K2) as polarized light (K1, K2) from the first or second body ( 1 . 11 ) exit. Method according to Claim 1, characterized in that method step a) comprises the following substeps: a1) the first or second body ( 1 . 11 ) is placed in a coating chamber ( 20 ) which contains a hydrocarbon monomer in gaseous state, a2) in the coating chamber ( 20 ) an electric field is generated by between a first electrode ( 21 ) and a second electrode spaced from it ( 22 ) an electrical voltage is applied, a3) the first or second body ( 1 . 11 ) is inside the coating chamber ( 20 ) arranged so that at least part of the first or second boundary surface ( 2 . 12 ) is in the electric field, a4) the electric voltage is selected so that it between the electrodes ( 21 . 22 ) a gas discharge is triggered, which leads to a flow of ions of the hydrocarbon monomer in the direction of the first or second boundary surface ( 2 . 12 ) and there leads to an accumulation and polymerization of the ions, so that on the first or second boundary surface ( 2 . 12 ) a layer of a hydrocarbon polymer, namely the first or second polymer layer ( 3 . 13 ) is formed. A method according to claim 2, characterized in that as Hydrocarbon monomer is a monomer of a saturated hydrocarbon or a monomer of an aliphatic hydrocarbon is used. A method according to claim 3, characterized in that a monomer of octane C ₈ H _{18 is} used as the hydrocarbon monomer. Method according to one of claims 2 to 4, characterized in that the partial pressure of the hydrocarbon monomer in the coating chamber ( 20 ) is selected between 0.1 and 0.3 Pa. Method according to one of claims 2 to 5, characterized in that before the execution of sub-step a4) - the coating chamber ( 20 ) is evacuated and then - the hydrocarbon monomer into the coating chamber ( 20 ) is introduced so that the coating chamber ( 20 ) contains essentially no gas other than the hydrocarbon monomer during the execution of sub-step a4). Method according to one of claims 2 to 6, characterized in that that the Amount of electrical voltage between 1300 and 2000 volts is selected. Method according to one of claims 2 to 7, characterized in that that the electrical voltage a DC voltage or an AC voltage is. Method according to one of claims 2 to 8, characterized in that the first or second boundary surface ( 2 . 12 ) is oriented during the execution of sub-step a4) such that - when coating the first boundary surface ( 2 ) a first edge area ( 6 ) of the first boundary surface ( 2 ) of the first electrode ( 21 ) and a second edge area ( 7 ) of the first boundary surface ( 2 ) the second electrode ( 22 ) is facing, and - when coating the second boundary surface ( 12 ) a first edge area ( 16 ) of the second boundary surface ( 12 ) of the first electrode ( 21 ) and a second edge area ( 17 ) of the second boundary surface ( 12 ) the second electrode ( 22 ) facing, the amount of the angle β between the normal of the first boundary surface ( 1 ) and the middle direction of the field lines ( 23 ) of electric field between 80 ° and 100 °, preferably between 85 ° and 95 °. Method according to claim 9, characterized in that the first or second boundary surface ( 2 . 12 ) is oriented during the execution of sub-step a4) such that the amount of the angle β between the normal of the first or second boundary surface ( 2 . 12 ) and the mean direction of the field lines ( 23 ) of the electric field is between 87 ° and 89 ° or between 91 ° and 93 °. Method according to claim 9 or 10, characterized in that in method step b) the first edge region ( 6 ) of the first boundary surface ( 2 ) the second border area ( 17 ) of the second boundary surface ( 12 ) opposite and the second edge area ( 7 ) of the first boundary surface ( 2 ) the first edge area ( 16 ) of the second boundary surface ( 12 ) is arranged opposite. Method according to one of claims 9 to 11, characterized in that before the execution of method step c) the body ( 1 . 11 ) are oriented so that the solder (L) on the first and / or the second boundary surface ( 2 . 12 ) forms an angle δ with the horizontal (S), which is given by δ = 90 ° -β and which during the filling of the liquid crystal (F) into the intermediate space ( 50 ) is kept essentially constant. Method according to one of claims 1 to 12, characterized in that the pressure inside the coating chamber ( 20 ) and the electrical voltage are selected so that the gas discharge takes place as a glow discharge. Method according to one of claims 1 to 13, characterized in that the first and the second body ( 1 . 11 ) each a prism-shaped body ( 1 . 11 ) is used so that the first and the second boundary surface ( 2 . 12 ) are each flat surfaces. Method according to one of claims 1 to 14, characterized in that the first and the second boundary surface ( 2 . 12 ) are aligned parallel to one another in method step b). Method according to one of claims 1 to 15, characterized in that the first and second bodies ( 1 . 11 ) a vitreous body is used in each case. Method according to one of claims 1 to 16, characterized in that between the boundary surfaces ( 2 . 12 ) at least one spacer ( 4 . 5 ) is arranged, which the two bodies ( 1 . 11 ) fixed in their mutual position. Method according to one of claims 1 to 17, characterized in that between the boundary surfaces ( 2 . 12 ) a sealing material is introduced so that the space is completely closed. Method according to one of claims 1 to 18, characterized in that the liquid crystal (F) used is one whose molecules are due to the contact of the liquid crystal (F) with the polymer layers ( 3 . 13 ) are aligned homeotropically. Method according to one of claims 1 to 19, characterized in that that as Liquid crystal (F) a smectic or a nematic liquid crystal is used. A method according to claim 20, characterized in that a nematic liquid crystal is used as the liquid crystal (F), the molecules of which are due to the contact of the liquid crystal (F) with the polymer layers (F) 3 . 13 ) on average perpendicular to the boundary surfaces ( 2 . 12 ) are aligned. Method according to one of claims 1 to 21, characterized in that the mutual position of the body ( 1 . 11 ) is chosen so that the expansion of the space ( 50 ) to the boundary surfaces ( 2 . 12 ) vertical direction (L) is between 400 nm and 50 μm. A method according to claim 22, characterized in that the mutual position of the body ( 1 . 11 ) is chosen so that the expansion of the space ( 50 ) to the boundary surfaces ( 2 . 12 ) vertical direction (L) is 20 μm to 50 μm. Method according to one of claims 1 to 23, characterized in that the thickness of the polymer layers ( 3 . 13 ) is between 50 nm and 100 μm. Polarizer for light, with a first transparent body ( 1 ), which has at least a first boundary surface ( 2 ), and a second transparent body ( 11 ), which has at least a second boundary surface ( 12 ), characterized in that a) the first boundary surface ( 2 ) of the first body ( 1 ) with a first transparent polymer layer ( 3 ) and the second boundary surface ( 12 ) of the second body ( 11 ) with a second transparent polymer layer ( 13 ) are coated, which polymer layers ( 3 . 13 ) are such that light whose angle of incidence (φ) hits the first or second boundary surface ( 2 . 12 ) is within a certain angular interval, neither on the first still on the second boundary surface ( 2 . 12 ) is totally reflected, b) the two bodies ( 1 . 11 ) are arranged relative to one another in such a way that the first and the second polymer layer ( 3 . 13 ) facing each other essentially opposite each other and forming a space ( 50 ) are spaced from each other, which is filled with a transparent liquid crystal (F), which is thus with the first and with the second polymer layer ( 3 . 13 ) is in contact, c) the first and second polymer layers ( 3 . 13 ) and the liquid crystal (F) are such that the molecules (M) of the liquid crystal (F) due to their contact with the polymer layers ( 3 . 13 ) are oriented on average in a certain preferred direction, and d) the liquid crystal (F) is thereby birefringent in such a way that unpolarized light (E), its angle of incidence (φ) on the first or second boundary surface ( 2 . 12 ) lies within the determined angular interval, at the interface between the first or second polymer layer ( 3 . 13 ) and the liquid crystal (F) is split into a first and a second polarized component (K1, K2), wherein - either the first and the second component (K1, K2) are linearly polarized orthogonally to one another, - or the first component (K1 ) is elliptically or circularly polarized and the second component (K2) is orthogonally elliptically or orthogonally circularly polarized to the first component (K1), - and the first component (K1) at the interface between the first or second polymer layer ( 3 . 13 ) and the liquid crystal (F) is essentially totally reflected and the second component (K2) essentially from the first body ( 1 ) through the liquid crystal (F) into the second body ( 11 ) passes, at least one of the components (K1, K2) as polarized light (K1, K2) from the first or second body ( 1 . 11 ) exit. Polarizer according to claim 25, characterized in that the first or second polymer layer ( 3 . 13 ) are produced as follows: a1) the first or second body ( 1 . 11 ) is placed in a coating chamber ( 20 ) which contains a hydrocarbon monomer in gaseous state, a2) in the coating chamber ( 20 ) an electric field is generated by between a first electrode ( 21 ) and a second electrode spaced from it ( 22 ) an electrical voltage is applied, a3) the first or second body ( 1 . 11 ) is inside the coating chamber ( 20 ) arranged so that at least part of the first or second boundary surface ( 2 . 12 ) is in the electric field, a4) the electric voltage is selected so that it between the electrodes ( 21 . 22 ) a gas discharge is triggered, which leads to a flow of ions of the hydrocarbon monomer in the direction of the first or second boundary surface ( 2 . 12 ) and there leads to an accumulation and polymerization of the ions, so that on the first or second boundary surface ( 2 . 12 ) a layer of a hydrocarbon polymer, namely the first or second polymer layer ( 3 . 13 ) is formed. Polarizer according to claim 26, characterized in that this Hydrocarbon monomer is a monomer of a saturated hydrocarbon or is an aliphatic hydrocarbon monomer. Polarizer according to claim 26, characterized in that the hydrocarbon monomer is a monomer of octane C ₈ H ₁₈ . Polarizer according to one of claims 26 to 28, characterized in that the partial pressure of the hydrocarbon monomer in the coating chamber ( 20 ) is between 0.1 and 0.3 Pa. Polarizer according to one of claims 26 to 29, characterized in that before the execution of sub-step a4) - the coating chamber ( 20 ) is evacuated and then - the hydrocarbon monomer into the coating chamber ( 20 ) is introduced so that the coating chamber ( 20 ) contains essentially no gas other than the hydrocarbon monomer during the execution of sub-step a4). Polarizer according to one of claims 26 to 30, characterized in that that the The amount of electrical voltage is between 1300 and 2000 volts. Polarizer according to one of claims 26 to 31, characterized in that that the electrical voltage a DC voltage or an AC voltage is. Polarizer according to one of claims 26 to 32, characterized in that the first or second boundary surface ( 2 . 12 ) is oriented during the execution of sub-step a4) such that - when coating the first boundary surface ( 2 ) a first edge area ( 6 ) of the first boundary surface ( 2 ) of the first electrode ( 21 ) and a second edge area ( 7 ) of the first boundary surface ( 2 ) the second electrode ( 22 ) is facing, and - when coating the second boundary surface ( 12 ) a first edge area ( 16 ) of the second boundary surface ( 12 ) of the first electrode ( 21 ) and a second edge area ( 17 ) of the second boundary surface ( 12 ) the second electrode ( 22 ) is facing where the amount of the angle β between the normal of the first boundary surface ( 1 ) and the middle direction of the field lines ( 23 ) of the electric field is between 80 ° and 100 °, preferably between 85 ° and 95 °. Polarizer according to claim 33, characterized in that the first or second boundary surface ( 2 . 12 ) is oriented during the execution of sub-step a4) such that the amount of the angle β between the normal of the first or second boundary surface ( 2 . 12 ) and the mean direction of the field lines ( 23 ) of the electric field is between 87 ° and 89 ° or between 91 ° and 93 °. Polarizer according to claim 33 or 34, characterized in that in the production step b) the first edge region ( 6 ) of the first boundary surface ( 2 ) the second border area ( 17 ) of the second boundary surface ( 12 ) opposite and the second edge area ( 7 ) of the first boundary surface ( 2 ) the first edge area ( 16 ) of the second boundary surface ( 12 ) is arranged opposite one another. Polarizer according to one of Claims 33 to 35, characterized in that, in order to produce the polarizer, the liquid crystal in the intermediate space ( 50 ) is filled with the body ( 1 . 11 ) are oriented so that the solder (L) on the first and / or the second boundary surface ( 2 . 12 ) forms an angle δ with the horizontal (S), which is given by δ = 90 ° –β. Polarizer according to one of claims 26 to 36, characterized in that the pressure inside the coating chamber ( 20 ) and the electrical voltage are selected so that the gas discharge takes place as a glow discharge. Polarizer according to one of claims 25 to 37, characterized in that the first and the second boundary surface ( 2 . 12 ) are each flat surfaces. Polarizer according to claim 38, characterized in that the first and the second body ( 1 . 11 ) are prisms. Polarizer according to one of claims 25 to 39, characterized in that that the first and the second boundary surface aligned parallel to each other are. Polarizer according to one of claims 25 to 40, characterized in that the first and the second body ( 1 . 11 ) each consist of glass. Polarizer according to one of claims 25 to 41, characterized in that between the boundary surfaces ( 2 . 12 ) at least one spacer ( 4 . 5 ) is arranged, which the two bodies ( 1 . 11 ) is able to fix in their mutual position. Polarizer according to one of claims 25 to 42, characterized in that between the boundary surfaces ( 2 . 12 ) a sealing material is introduced so that the space ( 50 ) is completely closed. Polarizer according to one of claims 25 to 43, characterized in that the liquid crystal (F) is one whose molecules are due to the contact of the liquid crystal (F) with the polymer layers ( 3 . 13 ) are aligned homeotropically. Polarizer according to one of claims 25 to 44, characterized in that that the Liquid crystal (F) is a smectic or a nematic liquid crystal (F). Polarizer according to claim 45, characterized in that the liquid crystal (F) is a nematic liquid crystal (F), the molecules of which are due to the contact of the liquid crystal (F) with the polymer layers ( 3 . 13 ) on average perpendicular to the boundary surfaces ( 2 . 12 ) are aligned. Polarizer according to one of claims 25 to 46, characterized in that the expansion of the intermediate space ( 50 ) to the boundary surfaces ( 2 . 12 ) vertical direction (L) is between 400 nm and 50 μm. Polarizer according to claim 47, characterized in that the expansion of the intermediate space ( 50 ) to the boundary surfaces ( 2 . 12 ) vertical direction (L) is 20 μm to 50 μm. Polarizer according to one of claims 25 to 48, characterized in that the thickness of the polymer layers ( 3 . 13 ) is between 50 nm and 100 μm.