DE102016121694A1 - lighting device - Google Patents

Abstract

A lighting device is specified. The illumination device comprises a phosphor having the general empirical formula (MA) a (MB) b (MC) c (MD) d (TA) e (TB) f (TC) g (TD) h (TE) i (TF) j (XA) k (XB) l (XC) m (XD) n. Where MA is selected from a group of monovalent metals, MB is selected from a group of divalent metals, MC is selected from a group of trivalent metals, MD is selected from a group of tetravalent metals, TA is selected from a group of monovalent metals , TB is selected from a group of divalent metals, TC is selected from a group of trivalent metals, TD is selected from a group of tetravalent metals, TE is selected from a group of pentavalent elements, TF is selected from a group of hexavalent elements , XA is selected from a group of elements comprising halogens, XB is selected from a group of elements comprising O, S and combinations thereof, XC = N and XD = C. Further: a + b + c + d = t; e + f + g + h + i + j = u; k + 1 + m + n = v; a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j - k - 2l - 3m - 4n = w; 0.8 ≤ t ≤ 1; - 3.5 ≤ u ≤ 4; 3.5 ≤ v ≤ 4; (-0.2) ≤ w ≤ 0.2 and 0 ≤ m <0.875 v and / or v ≥ l> 0.125 v.

Description

The invention relates to a lighting device, in particular a conversion light-emitting diode (conversion LED).

Phosphors that can be efficiently excited with ultraviolet, blue, or green primary radiation and have efficient emission in the blue, green, yellow, red, or deep red spectral region are of great interest for the production of white and color conversion LEDs. Conversion LEDs are used in many applications, such as general lighting, display backlighting, signage, scoreboards, in automobiles, and many other consumer products. Conversion LEDs for the backlighting of display elements, such as displays, are very different from conversion LEDs for general lighting. The requirements for conversion LEDs for general lighting consist in particular in a high luminous efficacy combined with high efficiency, a high color rendering index and a color temperature below 3500 K. For conversion LEDs for the backlighting of display elements in particular phosphors with narrowband emissions in the blue, green and red spectral range needed to cover as wide a color space as possible. In addition, there is a great demand for colored conversion LEDs which reproduce colors adapted to consumer requirements (so-called "color on demand" applications).

Previous white-emitting conversion LEDs for general lighting and backlighting use a semiconductor chip that emits a blue primary radiation and a red and green phosphor. A disadvantage of this solution is that the epitaxially grown semiconductor chips, based for example on GaN or InGaN, may exhibit fluctuations in the peak wavelength of the emitted primary radiation. This leads to fluctuations in the total white radiation, such as a change of the color location and the color reproduction, since the primary radiation contributes the blue component to the total radiation. This is particularly problematic in the use of multiple semiconductor chips in a device.

In order to prevent fluctuations, the semiconductor chips are sorted according to their color locations ("binning"). The closer the tolerances to the wavelength of the emitted primary radiation are set, the higher the quality of conversion LEDs consisting of more than one semiconductor chip. But even after sorting with tight tolerances, the peak wavelength of the semiconductor chips may change significantly at variable operating temperatures and throughput currents. In general lighting and other applications, this may result in a change in optical properties, such as color location and color temperature.

In the backlighting of display elements, such as displays in televisions, computer monitors, tablets and smartphones manufacturers are keen to reproduce the colors alive and lifelike, as this is very attractive to consumers. For the backlighting of display elements therefore light sources with very narrow band emissions, ie a low half width, in the green, blue and red spectral range are needed to cover the widest possible color space. As light sources for backlighting applications, a blue semiconductor chip with a phosphor having a peak wavelength in the green and a phosphor having a peak wavelength in the red spectral range are predominantly combined.

Conversion LEDs for backlighting applications conventionally employ as green phosphor, for example, an yttrium-aluminum garnet, a lutetium-aluminum garnet, or a β-SiAlON (Si _6-z Al _z O _z N _8-z : RE or Si _6-x Al _z O _y N _8-y : RE _z where RE = rare-earth metal). However, yttrium aluminum garnet has an emission peak with a large half-width, so that significant filter losses limit the achievable color space and also reduce efficiency. β-SiAlON exhibits a narrowband emission in the green spectral range with a half-value width of less than 60 nm, which leads to a more saturated green reproduction than with a garnet phosphor. However, the β-SiAlONs lack good internal and external quantum efficiency, which makes the overall backlighting less efficient. Furthermore, the production of these phosphors requires very high temperatures and complex equipment. Thus, the phosphor is very expensive to manufacture and thus the production of conversion LEDs with this phosphor.

Quantum dots are also used to convert primary radiation into backlighting applications due to their very narrow band emission. However, quantum dots are very unstable. In addition, most commercially available quantum dots have harmful elements such as Hg or Cd, whose Concentration under the regulations of the RoHS (Restriction of Hazardous Substances, EU Directive 2011/65 / EU ) is limited in commercial electrical and electronic equipment.

Known blue-green to green phosphors for conversion LEDs are, for example, the phosphors Ca ₈ Mg (SiO ₄ ) ₄ Cl ₂ : Eu, (Sr, Ba) ₂ SiO ₄ : Eu and Lu ₃ (Al, Ga) ₅ O ₁₂ : Ce. Conversion LEDs with these phosphors, however, have insufficient color purity and can not achieve certain color locations, which is why they are out of the question for many "color on demand" applications.

The object of the present invention is to provide a lighting device, in particular a conversion LED, which is improved over the prior art and which can be used in particular for general lighting, backlighting and "color on demand" applications.

The object is achieved by a lighting device according to independent claim 1. Advantageous embodiments and further developments of the present invention are specified in the dependent claims.

It is indicated a phosphor. The phosphor has the general empirical formula:
(MA) _a (MB) _b (MC) _c (MD) _d (TA) _e (TB) _f (TC) _g (TD) _h (TE) _i (TF) _j (XA) _k (XB) ₁ (XC ) _m (XD) _n.

• – a + b + c + d = t;
• – e + f + g + h + i + j = u
• – k + l + m + n = v
• – a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j – k – 2l – 3m – 4n = w
• – 0.8 ≤ t ≤ 1
• – 3.5 ≤ u ≤ 4
• – 3.5 ≤ v ≤ 4
• – (–0.2) ≤ w ≤ 0.2.

Where MA is selected from a group of monovalent metals, MB is selected from a group of divalent metals, MC is selected from a group of trivalent metals, MD is selected from a group of tetravalent metals, TA is selected from a group of monovalent metals , TB is selected from a group of divalent metals, TC is selected from a group of trivalent metals, TD is selected from a group of tetravalent metals, TE is selected from a group of pentavalent elements, TF is selected from a group of hexavalent elements , XA is selected from a group of elements comprising halogens, XB is selected from a group of elements comprising O, S and combinations thereof, XC = N and XD = C.

• - a + b + c + d = t;
• - e + f + g + h + i + j = u
• - k + 1 + m + n = v
• - a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j - k - 2l - 3m - 4n = w
• - 0.8 ≤ t ≤ 1
• - 3.5 ≤ u ≤ 4
• - 3.5 ≤ v ≤ 4
• - (-0.2) ≤ w ≤ 0.2.

Here and below, phosphors are described by means of molecular formulas. It is possible with the stated empirical formulas that the phosphor has further elements approximately in the form of impurities, these impurities taken together should preferably have at most one part by weight of the phosphor of at most 1 part per million or 10 parts per million (ppm).

In accordance with at least one embodiment, the phosphor having the general empirical formula applies
(MA) _a (MB) _b (MC) _c (MD) _d (TA) _e (TB) _f (TC) _g (TD) _h (TE) _i (TF) _j (XA) _k (XB) ₁ (XC ) _m (XD) _n : 0 ≤ m <0.875 v and / or v ≥ l> 0.125 v.

• – MA aus einer Gruppe von monovalenten Metallen ausgewählt ist, die Li, Na, K, Rb, Cs, Cu, Ag und Kombinationen daraus umfasst,
• – MB aus einer Gruppe von divalenten Metallen ausgewählt ist, die Mg, Ca, Sr, Ba, Zn, Mn, Eu, Yb, Ni, Fe, Co und Kombinationen daraus umfasst,
• – MC aus einer Gruppe von trivalenten Metallen ausgewählt ist, die Y, Fe, Cr, Sc, In, Seltene Erden und Kombinationen daraus umfasst,
• – MD aus einer Gruppe von tetravalenten Metallen ausgewählt ist, die Zr, Hf, Mn, Ce und Kombinationen daraus umfasst,
• – TA aus einer Gruppe von monovalenten Metallen ausgewählt ist, die Li, Na, Cu, Ag und Kombinationen daraus umfasst,
• – TB aus einer Gruppe von divalenten Metallen ausgewählt ist, Mg, Zn, Mn, Eu, Yb, Ni und Kombinationen daraus umfasst,
• – TC aus einer Gruppe von trivalenten Metallen ausgewählt ist, die B, Al, Ga, In, Y, Fe, Cr, Sc, Seltene Erden und Kombinationen daraus umfasst,
• – TD aus einer Gruppe von tetravalenten Metallen ausgewählt ist, die Si, Ge, Sn, Mn, Ti, Zr, Hf, Ce und Kombinationen daraus umfasst,
• – TE aus einer Gruppe von pentavalenten Elementen ausgewählt ist, die P, Ta, Nb, V und Kombinationen daraus umfasst,
• – TF aus einer Gruppe von hexavalenten Elementen ausgewählt ist, die W, Mo und Kombinationen daraus umfasst,
• – XA aus einer Gruppe von Elementen ausgewählt ist, die F, Cl, Br und Kombinationen daraus umfasst,
• – XB aus einer Gruppe von Elementen ausgewählt ist, die O, S und Kombinationen daraus umfasst,
• – XC = N
• – XD = C
• – a + b + c + d = t
• – e + f + g + h + i + j = u
• – k + l + m + n = v
• – a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j – k – 2l – 3m – 4n = w
• – 0.8 ≤ t ≤ 1
• – 3.5 ≤ u ≤ 4
• – 3.5 ≤ v ≤ 4
• – (–0.2) ≤ w ≤ 0.2 und 0 ≤ m < 0,875 v und/oder v ≥ l > 0,125 v.

There is provided a lighting device comprising a phosphor. The phosphor has the following general empirical formula:
(MA) _a (MB) _b (MC) _c (MD) _d (TA) _e (TB) _f (TC) _g (TD) _h (TE) _i (TF) _j (XA) _k (XB) ₁ (XC ) _m (XD) _n ,
in which

• MA is selected from a group of monovalent metals comprising Li, Na, K, Rb, Cs, Cu, Ag and combinations thereof;
• MB is selected from a group of divalent metals comprising Mg, Ca, Sr, Ba, Zn, Mn, Eu, Yb, Ni, Fe, Co and combinations thereof;
• MC is selected from a group of trivalent metals comprising Y, Fe, Cr, Sc, In, rare earths and combinations thereof;
• MD is selected from a group of tetravalent metals comprising Zr, Hf, Mn, Ce and combinations thereof,
• TA is selected from a group of monovalent metals comprising Li, Na, Cu, Ag and combinations thereof,
• TB is selected from a group of divalent metals, comprising Mg, Zn, Mn, Eu, Yb, Ni and combinations thereof,
• TC is selected from a group of trivalent metals comprising B, Al, Ga, In, Y, Fe, Cr, Sc, rare earths and combinations thereof,
• TD is selected from a group of tetravalent metals comprising Si, Ge, Sn, Mn, Ti, Zr, Hf, Ce and combinations thereof,
• TE is selected from a group of pentavalent elements comprising P, Ta, Nb, V and combinations thereof,
• TF is selected from a group of hexavalent elements comprising W, Mo and combinations thereof,
• XA is selected from a group of elements comprising F, Cl, Br and combinations thereof,
• XB is selected from a group of elements comprising O, S and combinations thereof,
• - XC = N
• - XD = C
• - a + b + c + d = t
• - e + f + g + h + i + j = u
• - k + 1 + m + n = v
• - a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j - k - 2l - 3m - 4n = w
• - 0.8 ≤ t ≤ 1
• - 3.5 ≤ u ≤ 4
• - 3.5 ≤ v ≤ 4
• - (-0.2) ≤ w ≤ 0.2 and 0 ≤ m <0.875 v and / or v ≥ l> 0.125 v.

In one embodiment, the illumination device is a conversion light emitting diode.

A conversion light-emitting diode (conversion LED) is indicated. The conversion light emitting diode (conversion LED) comprises a phosphor of the molecular formula
(MA) _a (MB) _b (MC) _c (MD) _d (TA) _e (TB) _f (TC) _g (TD) _h (TE) _i (TF) _j (XA) _k (XB) ₁ (XC ) _m (XD) _n.

• – a + b + c + d = t;
• – e + f + g + h + i + j = u
• – k + l + m + n = v
• – a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j – k – 2l – 3m – 4n = w
• – 0.8 ≤ t ≤ 1
• – 3.5 ≤ u ≤ 4
• – 3.5 ≤ v ≤ 4
• – (–0.2) ≤ w ≤ 0.2. Insbesondere ist der Leuchtstoff in einem Konversionselement angeordnet.

Where MA is selected from a group of monovalent metals, MB is selected from a group of divalent metals, MC is selected from a group of trivalent metals, MD is selected from a group of tetravalent metals, TA is selected from a group of monovalent metals , TB is selected from a group of divalent metals, TC is selected from a group of trivalent metals, TD is selected from a group of tetravalent metals, TE is selected from a group of pentavalent elements, TF is selected from a group of hexavalent elements , XA is selected from a group of elements comprising halogens, XB is selected from a group of elements comprising O, S and combinations thereof, XC = N and XD = C.

• - a + b + c + d = t;
• - e + f + g + h + i + j = u
• - k + 1 + m + n = v
• - a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j - k - 2l - 3m - 4n = w
• - 0.8 ≤ t ≤ 1
• - 3.5 ≤ u ≤ 4
• - 3.5 ≤ v ≤ 4
• - (-0.2) ≤ w ≤ 0.2. In particular, the phosphor is arranged in a conversion element.

• – MA aus einer Gruppe von monovalenten Metallen ausgewählt ist, die Li, Na, K, Rb, Cs, Cu, Ag und Kombinationen daraus umfasst,
• – MB aus einer Gruppe von divalenten Metallen ausgewählt ist, die Mg, Ca, Sr, Ba, Zn, Mn, Eu, Yb, Ni, Fe, Co und Kombinationen daraus umfasst,
• – MC aus einer Gruppe von trivalenten Metallen ausgewählt ist, die Y, Fe, Cr, Sc, In, Seltene Erden und Kombinationen daraus umfasst,
• – MD aus einer Gruppe von tetravalenten Metallen ausgewählt ist, die Zr, Hf, Mn, Ce und Kombinationen daraus umfasst,
• – TA aus einer Gruppe von monovalenten Metallen ausgewählt ist, die Li, Na, Cu, Ag und Kombinationen daraus umfasst,
• – TB aus einer Gruppe von divalenten Metallen ausgewählt ist, Mg, Zn, Mn, Eu, Yb, Ni und Kombinationen daraus umfasst,
• – TC aus einer Gruppe von trivalenten Metallen ausgewählt ist, die B, Al, Ga, In, Y, Fe, Cr, Sc, Seltene Erden und Kombinationen daraus umfasst,
• – TD aus einer Gruppe von tetravalenten Metallen ausgewählt ist, die Si, Ge, Sn, Mn, Ti, Zr, Hf, Ce und Kombinationen daraus umfasst,
• – TE aus einer Gruppe von pentavalenten Elementen ausgewählt ist, die P, Ta, Nb, V und Kombinationen daraus umfasst,
• – TF aus einer Gruppe von hexavalenten Elementen ausgewählt ist, die W, Mo und Kombinationen daraus umfasst,
• – XA aus einer Gruppe von Elementen ausgewählt ist, die F, Cl, Br und Kombinationen daraus umfasst,
• – XB aus einer Gruppe von Elementen ausgewählt ist, die O, S und Kombinationen daraus umfasst,
• – XC = N
• – XD = C
• – a + b + c + d = t
• – e + f + g + h + i + j = u
• – k + l + m + n = v
• – a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j – k – 2l – 3m – 4n = w
• – 0.8 ≤ t ≤ 1
• – 3.5 ≤ u ≤ 4
• – 3.5 ≤ v ≤ 4
• – (–0.2) ≤ w ≤ 0.2 und 0 ≤ m < 0,875 v und/oder v ≥ l > 0,125 v.

According to one embodiment, the illumination device, in particular the conversion LED, comprises a primary radiation source, which is set up to emit an electromagnetic primary radiation during operation of the illumination device, in particular the conversion LED. Furthermore, the illumination device, in particular the conversion LED comprises a conversion element which is arranged in the beam path of the electromagnetic primary radiation. The conversion element comprises a phosphor, which is adapted to at least partially convert the electromagnetic primary radiation into an electromagnetic secondary radiation during operation of the illumination device, in particular the conversion LED. The phosphor has in particular the following empirical formula:
(MA) _a (MB) _b (MC) _c (MD) _d (TA) _e (TB) _f (TC) _g (TD) _h (TE) _i (TF) _j (XA) _k (XB) ₁ (XC ) _m (XD) _n ,
in which

• MA is selected from a group of monovalent metals comprising Li, Na, K, Rb, Cs, Cu, Ag and combinations thereof;
• MB is selected from a group of divalent metals comprising Mg, Ca, Sr, Ba, Zn, Mn, Eu, Yb, Ni, Fe, Co and combinations thereof;
• MC is selected from a group of trivalent metals comprising Y, Fe, Cr, Sc, In, rare earths and combinations thereof;
• MD is selected from a group of tetravalent metals comprising Zr, Hf, Mn, Ce and combinations thereof,
• TA is selected from a group of monovalent metals comprising Li, Na, Cu, Ag and combinations thereof,
• TB is selected from a group of divalent metals, comprising Mg, Zn, Mn, Eu, Yb, Ni and combinations thereof,
• TC is selected from a group of trivalent metals comprising B, Al, Ga, In, Y, Fe, Cr, Sc, rare earths and combinations thereof,
• TD is selected from a group of tetravalent metals comprising Si, Ge, Sn, Mn, Ti, Zr, Hf, Ce and combinations thereof,
• TE is selected from a group of pentavalent elements comprising P, Ta, Nb, V and combinations thereof,
• TF is selected from a group of hexavalent elements comprising W, Mo and combinations thereof,
• XA is selected from a group of elements comprising F, Cl, Br and combinations thereof,
• XB is selected from a group of elements comprising O, S and combinations thereof,
• - XC = N
• - XD = C
• - a + b + c + d = t
• - e + f + g + h + i + j = u
• - k + 1 + m + n = v
• - a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j - k - 2l - 3m - 4n = w
• - 0.8 ≤ t ≤ 1
• - 3.5 ≤ u ≤ 4
• - 3.5 ≤ v ≤ 4
• - (-0.2) ≤ w ≤ 0.2 and 0 ≤ m <0.875 v and / or v ≥ l> 0.125 v.

0 ≤ m <0.875 v and / or v ≥ l> 0.125 v means that the mole fraction of XC, ie nitrogen, in the luminescent material is less than 87.5 mol% relative to the total amount v of XA, XB, XC and X XD is and / or the mole fraction of XB, ie oxygen and / or sulfur, in the phosphor is above 12.5 mole% with respect to the total amount of material v at XA, XB, XC and XD.

The fact that the phosphor at least partially converts the electromagnetic primary radiation into an electromagnetic secondary radiation may mean that the electromagnetic primary radiation is partially absorbed by the phosphor and emitted as secondary radiation with a wavelength range at least partially different from the primary radiation. In this so-called partial conversion, the illumination device, in particular the conversion LED, emits, in particular, a total radiation that is composed of the primary radiation and the secondary radiation. It is thus possible for the illumination device, in particular the conversion LED, to emit a mixed radiation of primary radiation and secondary radiation.

The fact that the phosphor at least partially converts the electromagnetic primary radiation into an electromagnetic secondary radiation may also mean that the electromagnetic primary radiation is almost completely absorbed by the phosphor and emitted in the form of electromagnetic secondary radiation. The emitted radiation or total radiation of the illumination device, in particular the conversion LED according to this embodiment thus corresponds almost completely to the electromagnetic secondary radiation. Almost complete conversion is a conversion over 90%, especially over 95% to understand. It is therefore possible for the illumination device, in particular the conversion LED, to predominantly emit secondary radiation.

In accordance with at least one embodiment, the primary radiation source is a layer sequence with an active layer, which is set up to emit an electromagnetic primary radiation during operation of the illumination device.

In this context, "layer sequence" is understood as meaning a layer sequence comprising more than one layer, for example a sequence of a p-doped and an n-doped semiconductor layer, wherein the layers are arranged one above the other and wherein at least one active layer is contained, the primary electromagnetic radiation emitted.

The layer sequence can be embodied as an epitaxial layer sequence or as a radiation-emitting semiconductor chip with an epitaxial layer sequence, that is to say as an epitaxially grown semiconductor layer sequence. In this case, the layer sequence can be implemented, for example, on the basis of InGaAlN. InGaAlN-based semiconductor chips and semiconductor layer sequences are, in particular, those in which the epitaxially produced semiconductor layer sequence has a layer sequence of different individual layers which contains at least one single layer comprising a material of the III-V compound semiconductor material system In _x Al _y Ga _1-xy N with 0 ≦ x ≦ 1, 0 ≦ y ≦ 1 and x + y ≦ 1. Semiconductor layer sequences which comprise at least one InGaAlN-based active layer can, for example, emit electromagnetic radiation in an ultraviolet to blue wavelength range.

The active semiconductor layer sequence may comprise, in addition to the active layer, further functional layers and functional regions, such as p- or n-doped charge carrier transport layers, ie electron or hole transport layers, undoped or p- or n-doped confinement, cladding or waveguide layers, barrier layers, planarization layers , Buffer layers, protective layers and / or electrodes and combinations thereof. Furthermore, one or more mirror layers can be applied, for example, on a side of the semiconductor layer sequence facing away from the growth substrate. The structures described here, the active layer or the further functional layers and areas are known to the person skilled in the art in particular with regard to structure, function and structure and are therefore not explained in detail at this point.

In one embodiment, the emitted primary radiation of the primary radiation source or of the active layer of the layer sequence lies in the near UV region to the blue region of the electromagnetic spectrum. In the near UV range, this may mean that the emitted primary radiation has a wavelength of between 300 nm and 420 nm inclusive. In the blue region of the electromagnetic spectrum may mean that the emitted primary radiation has a wavelength between 420 nm and 500 nm inclusive, preferably up to and including 460 nm.

In one embodiment, during operation of the illumination device, the active layer of the layer sequence emits electromagnetic primary radiation having a wavelength of between 300 nm and 500 nm inclusive or between 300 nm and 460 nm inclusive, preferably between 300 nm or 330 nm inclusive and 450 nm inclusive 440nm or 430nm.

In accordance with at least one embodiment, the primary radiation source or the layer sequence has a radiation exit surface over which the conversion element is arranged.

The fact that a layer or an element is arranged or applied "on" or "over" another layer or another element can mean here and below that the one layer or the one element is directly in direct mechanical and / or electrical contact is arranged on the other layer or the other element. Furthermore, it can also mean that the one layer or the one element is arranged indirectly on or above the other layer or the other element. In this case, further layers and / or elements can then be arranged between the one or the other layer or between the one or the other element.

The radiation exit surface is a main surface of the primary radiation source or of the layer sequence. The radiation exit surface extends in particular parallel to a main extension plane of the semiconductor layers of the layer sequence. For example, at least 75% or 90% of the primary radiation leaving the layer sequence emerges from the layer sequence via the radiation exit surface.

In one embodiment, the conversion element has a direct mechanical contact with the primary radiation source or the layer sequence, in particular with the radiation exit surface of the primary radiation source or the layer sequence.

In one embodiment, the conversion element is arranged over the entire surface over the primary radiation source or the layer sequence, in particular the radiation exit surface of the primary radiation source or the layer sequence.

In one embodiment, the conversion element comprises a matrix material. The phosphor can be distributed in the matrix material, for example it is homogeneously distributed in the matrix material.

The matrix material is both transparent to the primary radiation and to the secondary radiation and is for example selected from a group of materials consisting of: glasses, silicones, epoxy resins, polysilazanes, polymethacrylates and polycarbonates and combinations thereof. Transparent means that the matrix material is at least partially permeable to the primary radiation as well as to the secondary radiation.

In at least one embodiment, MA, MB, MC, MD, TA, TB, TC, TD, TE and TF are the corresponding monovalent, divalent, trivalent, tetravalent, pentavalent or hexavalent cations. In other words, MA and TA have the oxidation state +1, MB and TB the oxidation state +2, MC and TC the oxidation state +3, MD and TD the oxidation state +4, TE the oxidation state +5 and TF the oxidation state +6. In particular, XA, XB, XC and XD are the anions of the corresponding elements. In this case, XA preferably has the oxidation state -1, XB the oxidation state -2, XC, ie N, the oxidation state -3 and XD, ie C, the oxidation state -4.

In the WO 2013/175336 A1 describes a new family of red-emitting phosphors that exhibit emission with small half-widths. The phosphors disclosed therein have a content of at least 87.5% nitrogen and at most 12.5% oxygen with respect to the total amount of anionic elements of the phosphor. A higher oxygen content in the phosphors results according to the WO 2013/175336 A1 too unstable compounds.

The half-width is understood here and below to mean the spectral width at half the height of the maximum of the emission peak, FWHM for short or Full-width at half maximum. The emission peak is understood as the peak with the maximum intensity.

Surprisingly, the inventors of the present invention have found that a higher oxygen and / or sulfur content, ie an oxygen and / or sulfur content in the luminescent substance, exceeds 12.5 mol% with respect to the total amount of anionic elements or a lower nitrogen content. Thus, a nitrogen content in the phosphor below 87.5 mol% relative to the total amount of anionic elements leads to very stable and efficient phosphors with high quantum efficiency. The phosphors have a high absorption capacity in the UV range to green range, in particular between 300 nm and 500 nm or between 300 nm and 460 nm, preferably between 300 nm and 430 nm or 300 nm and 450 nm, and can thus be efficiently with excite a primary radiation in this wavelength range. The primary radiation can be converted by the luminescent material entirely (full conversion) or partially (partial conversion) into a longer-wave radiation, also denominatable as secondary radiation.

According to at least one embodiment, it is preferred that 0 ≦ m <0.75 v or v ≥ 1> 0.25 v, 0 ≦ m <0.625 v or v ≥ l> 0.375 v. Particularly preferred is: 0 ≤ m <0.5 v or v ≥ l> 0.5 v, 0 ≤ m <0.375 v or v ≥ l> 0.625 v, 0 ≤ m <0.25 v or v ≥ l> 0 , 7 v, 0 ≤ m <0.125 v or v ≥ l> 0.875 v or m = 0 or l = v.

The inventors have found that, surprisingly, with increasing oxygen and / or sulfur content or with decreasing nitrogen content, the peak wavelength of the phosphors shifts toward shorter wavelengths and, in addition, results in very stable phosphors. As a result, it is advantageously possible to set the desired peak wavelength of the phosphor accordingly by varying the oxygen content. Also, the peak wavelength and / or the half width of the phosphor can be varied by combinations or substitutions of the metals or elements MA, MB, MC, MD, TA, TB, TC, TD, TE, TF, XA, XC, XD and / or XB , It was thus found a way to provide phosphors, which can be adjusted specifically for a corresponding application in their properties, in particular the peak wavelength and the half-width, and are surprisingly also very stable. In particular, the phosphors can have very narrow half-widths, for example below 50 nm, below 30 nm or below 20 nm, which makes the phosphors interesting for many applications, for example for backlighting applications.

In the present case, the term "peak wavelength" refers to the wavelength in the emission spectrum at which the maximum intensity lies in the emission spectrum.

According to at least one embodiment, the phosphor having the empirical formula applies
(MA) _a (MB) _b (MC) _c (MD) _d (TA) _e (TB) _f (TC) _g (TD) _h (TE) _i (TF) _j (XA) _k (XB) ₁ (XC ) _m (XD) _n :
a + b + c + d = 1;
e + f + g + h + i + j = 4;
k + 1 + m + n = 4;
a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j - k - 2l - 3m - 4n = 0 and m <3.5 or l> 0.5. This is therefore an electroneutral phosphor.

In accordance with at least one embodiment, n = 0, k = 0, v = 4 and m <3.5 and l> 0.5. The phosphor then has the following empirical formula:
(MA) _a (MB) _b (MC) _c (MD) _d (TA) _e (TB) _f (TC) _g (TD) _h (TE) _i (TF) _j (XB) ₁ (XC) _m . MA, MB, MC, MD, TA, TB, TC, TD, TE, TF, XC and XB are as defined above. According to this embodiment, the phosphor has only nitrogen and oxygen, nitrogen and sulfur or nitrogen, sulfur and oxygen, preferably only nitrogen and oxygen, as anions. However, it is not excluded that further, including anionic elements are present in the form of impurities. Preferably, m <3.0 and l>1.0; m <2.5 and 1>1.5; m <2.0 and 1 <2.0; m <1.5 and 1>2.5; m <1.5 and 1>2.5; m <1.0 and l>3.0; m <0.5 and l> 3.5 or m = 0 and l = 4.

• – MA ist aus einer Gruppe von monovalenten Metallen ausgewählt, die Li, Na, K, Rb, Cs, Cu, Ag und Kombinationen daraus umfasst. Besonders bevorzugt ist MA aus einer Gruppe von monovalenten Metallen ausgewählt, die Li, Na, K, Rb und Kombinationen daraus umfasst,
• – MB ist aus einer Gruppe von divalenten Metallen ausgewählt, die Mg, Ca, Sr, Ba, Zn, Mn, Eu, Yb, Ni, Fe, Co und Kombinationen daraus umfasst. Besonders bevorzugt ist MB aus einer Gruppe von divalenten Metallen ausgewählt, die Mn, Eu, Yb und Kombinationen daraus umfasst. Ganz besonders bevorzugt ist MB = Eu oder eine Kombination aus Eu und Mn und/oder Yb,
• – TA ist aus einer Gruppe von monovalenten Metallen ausgewählt, die Li, Na, Cu, Ag und Kombinationen daraus umfasst. Besonders bevorzugt ist TA ist aus einer Gruppe von monovalenten Metallen ausgewählt, die Li, Na und Kombinationen daraus umfasst. Ganz besonders bevorzugt ist TA = Li,
• – TD ist aus einer Gruppe von tetravalenten Metallen ausgewählt, die Si, Ge, Sn, Mn, Ti, Zr, Hf, Ce und Kombinationen daraus umfasst. Besonders bevorzugt ist TD aus einer Gruppe von tetravalenten Metallen ausgewählt, die Si, Ge, Sn, Mn, Ti, und Kombinationen daraus umfasst. Ganz besonders bevorzugt ist TD = Si,
• – XB ist aus einer Gruppe von Elementen ausgewählt, die O, S und Kombinationen daraus umfasst. Besonders bevorzugt ist XB = O,
• – XC = N. Weiter gilt:
• – a + b = t,
• – e + h = u,
• – l + m = v,
• – a + 2b + e + 4h – 2l – 3m = w
• – 0.8 ≤ t ≤ 1
• – 3.5 ≤ u ≤ 4
• – 3.5 ≤ v ≤ 4
• – (–0.2) ≤ w ≤ 0.2
• – 0 ≤ m < 0,875 v und/oder v ≥ l > 0,125 v.

In accordance with at least one embodiment, the phosphor has the general empirical formula (MA) _a (MB) _b (TA) _e (TD) _h (XB) ₁ (XC) _m . The following applies:

• MA is selected from a group of monovalent metals comprising Li, Na, K, Rb, Cs, Cu, Ag and combinations thereof. More preferably, MA is selected from a group of monovalent metals comprising Li, Na, K, Rb and combinations thereof.
• MB is selected from a group of divalent metals comprising Mg, Ca, Sr, Ba, Zn, Mn, Eu, Yb, Ni, Fe, Co and combinations thereof. Most preferably, MB is selected from a group of divalent metals comprising Mn, Eu, Yb and combinations thereof. Most preferably MB = Eu or a combination of Eu and Mn and / or Yb,
• TA is selected from a group of monovalent metals comprising Li, Na, Cu, Ag and combinations thereof. More preferably, TA is selected from a group of monovalent metals comprising Li, Na, and combinations thereof. Most preferably, TA = Li,
• TD is selected from a group of tetravalent metals comprising Si, Ge, Sn, Mn, Ti, Zr, Hf, Ce and combinations thereof. More preferably, TD is selected from a group of tetravalent metals comprising Si, Ge, Sn, Mn, Ti, and combinations thereof. Most preferably, TD = Si,
• XB is selected from a group of elements comprising O, S and combinations thereof. Particularly preferred is XB = O,
• - XC = N. Next applies:
• - a + b = t,
• - e + h = u,
• - l + m = v,
• - a + 2b + e + 4h - 2l - 3m = w
• - 0.8 ≤ t ≤ 1
• - 3.5 ≤ u ≤ 4
• - 3.5 ≤ v ≤ 4
• - (-0.2) ≤ w ≤ 0.2
• 0 ≤ m <0.875 v and / or v ≥ l> 0.125 v.

• – MA ist aus einer Gruppe von monovalenten Metallen ausgewählt, die Li, Na, K, Rb, Cs, Cu, Ag und Kombinationen daraus umfasst. Bevorzugt ist MA aus einer Gruppe von monovalenten Metallen ausgewählt, die Li, Na, K, Rb und Kombinationen daraus umfasst,
• – MB ist aus einer Gruppe von divalenten Metallen ausgewählt, die Mg, Ca, Sr, Ba, Zn, Mn, Eu, Yb, Ni, Fe, Co und Kombinationen daraus umfasst. Bevorzugt ist aus einer Gruppe von divalenten Metallen ausgewählt, die Mn, Eu, Yb und Kombinationen daraus umfasst. Besonders bevorzugt ist MB = Eu oder eine Kombination von Eu mit Mn und/oder Yb,
• – TA ist aus einer Gruppe von monovalenten Metallen ausgewählt, die Li, Na, Cu, Ag und Kombinationen daraus umfasst. Bevorzugt ist TA aus einer Gruppe von monovalenten Metallen ausgewählt, die Li, Na und Kombinationen daraus umfasst. Besonders bevorzugt ist TA = Li,
• – TD ist aus einer Gruppe von tetravalenten Metallen ausgewählt, die Si, Ge, Sn, Mn, Ti, Zr, Hf, Ce und Kombinationen daraus umfasst. Bevorzugt ist TD aus einer Gruppe von tetravalenten Metallen ausgewählt, die Si, Ge, Sn, Mn, Ti, und Kombinationen daraus umfasst. Besonders bevorzugt ist TD = Si,
• – XB ist aus einer Gruppe von Elementen ausgewählt, die O, S und Kombinationen daraus umfasst. Bevorzugt ist XB = O.
• – XC = N. Weiter gilt: a + b = 1; e + h = 4; l + m = 4;
• – a + 2b + e + 4h – 2l – 3m = 0 und m < 3,5 oder l > 0,5.

In accordance with at least one embodiment, the phosphor has the general empirical formula:
(MA) _a (MB) _b (TA) _e (TD) _h (XB) ₁ (XC) _m . Where:

• MA is selected from a group of monovalent metals comprising Li, Na, K, Rb, Cs, Cu, Ag and combinations thereof. Preferably, MA is selected from a group of monovalent metals comprising Li, Na, K, Rb and combinations thereof,
• MB is selected from a group of divalent metals comprising Mg, Ca, Sr, Ba, Zn, Mn, Eu, Yb, Ni, Fe, Co and combinations thereof. Preferred is selected from a group of divalent metals comprising Mn, Eu, Yb and combinations thereof. Particularly preferred is MB = Eu or a combination of Eu with Mn and / or Yb,
• TA is selected from a group of monovalent metals comprising Li, Na, Cu, Ag and combinations thereof. Preferably, TA is selected from a group of monovalent metals comprising Li, Na, and combinations thereof. Particularly preferred is TA = Li,
• TD is selected from a group of tetravalent metals comprising Si, Ge, Sn, Mn, Ti, Zr, Hf, Ce and combinations thereof. Preferably, TD is selected from a group of tetravalent metals comprising Si, Ge, Sn, Mn, Ti, and combinations thereof. Particularly preferred is TD = Si,
• XB is selected from a group of elements comprising O, S and combinations thereof. Preferably, XB = O.
• - XC = N. Furthermore: a + b = 1; e + h = 4; l + m = 4;
• - a + 2b + e + 4h - 2l - 3m = 0 and m <3.5 or l> 0.5.

In accordance with at least one embodiment, the phosphor is an oxide, that is, only oxygen is present as an anionic element in the phosphor. The phosphor then has one of the following general empirical formulas:
(MA) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E,
(MA) ₁ (TA) _3-x (TD) _1-x (TB) _x (TC) _x (XB) ₄ : E,
(MA) _{1-x '} (MB) _x' (TA) ₃ (TD) _{1-x '} (TC) _x' (XB) ₄ : E,
(MA) _{1-x ''} (MB) _{x ''} (TA) _{3-x ''} (TD) _{1-x ''} (TB) _{2x ''} (XB) ₄ : E,
(MA) ₁ (TA) _3-2z (TB) _3z (TD) _1-z (XB) ₄ : E or
(MA) ₁ (TA) ₃ (TD) _{1-2z '} (TC) _z' (TE) _{z '} (XB) ₄ : E, where
XB = O,
0 ≤ x ≤ 1, for example, x = 0, 0.1; 0.2; 0.3; 0.4; 0.5;
0.6; 0.7; 0.8; 0.9 or 1, preferably 0 <x <1,
for example, x = 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8 or 0.9,
0 ≤ x '≤ 1, for example, x' = 0, 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8; 0.9 or 1, preferably 0 <x '<1,
for example, x '= 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8 or 0.9,
0 ≦ x "≦ 1, for example, x" = 0, 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8; 0.9 or 1, preferably 0 <x <1,
for example, x "= 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8 or 0.9,
0 ≦ z ≦ 1, preferably z = 0, 0.1; 0.2; 0.3; 0.4; 0.5; 0.6;
0.7; 0.8; 0.9 or 1, preferably 0 <z <1, for example z = 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8 or 0.9,
0 ≦ z '≦ 0.5, preferably 0 <z'<0.5, for example z '= 0, 0.1; 0.2; 0.3 or 0.4,
and E is selected from a group comprising Eu, Ce, Yb, Mn and combinations thereof.

Here and below, E can also be referred to as an activator. The activator and in particular its surroundings in the host lattice are responsible for the luminescence, in particular the peak wavelength of the emission of the phosphor.

The metals or elements MA, MB, TA, TB, TC, TD, TE and / or XB form the host lattice in the case of the phosphors, E can in this case be lattice sites of the cationic elements MA, MB, TA, TB, TC, TD and / or TE partially replace, or take interstitial spaces. In particular, E occupies the lattice sites of MA. For charge equalization, the proportion of other elements, for example TA and / or TD, may change.

In accordance with at least one embodiment, the phosphor is an oxide or oxonitride, preferably an oxonitride, and therefore has in its empirical formula only oxygen or oxygen and nitrogen as anionic elements. The phosphor can have one of the following general empirical formulas:
(MA) _1-y (TB) _y (TA) _3-2y (TC) _3y (TD) _1-y (XB) _4-4y (XC) _4y : E,
(MA) ₁ (TA) _{3-y '} (TC) _y' (TD) ₁ (XB) _{4-2y '} (XC) _2y' : E,
(MA) ₁ (TA) _{3-y "} (TB) _y" (TD) ₁ (XB) _{4-y "} (XC) _y" : E,
(MA) _{1-w '''} (MB) _w''' (TA) ₃ (TD) ₁ (XB) _{4-w '''} (XC) _w''' : E,
(MA) ₁ (TA) _{3-w '} (TC) _2w' (TD) _{1-w '} (XB) _4-w' (XC) _{w '} : E or
(MA) _{1-w ''} (MB) _{w ''} (TA) _{3-w ''} (TD) _{1-w ''} (TC) _{2w ''} (XB) _{4-2w ''} (XC) _{2w ''} : e,
in which
XB = O,
0 ≤ y ≤ 1, for example, y = 0, 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8; 0.9 or 1, preferably 0 <y <0.875,
for example, y = 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7 or 0.8, most preferably 0 ≤ y ≤ 0.4,
0 ≦ y '≦ 2, for example, y' = 0, 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8; 0.9; 1.0; 1.1; 1.2; 1.3; 1.4; 1.5; 1.6; 1.7; 1.8; 1.9 or 2.0, preferably 0 <y '≦ 1.75, particularly preferably 0 ≦ y' ≦ 0.9,
0 ≦ y '' ≦ 3, for example, y '' = 0, 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8; 0.9; 1.0; 1.1; 1.2; 1.3; 1.4; 1.5; 1.6; 1.7; 1.8; 1.9; 2.0; 2.1; 2.2; 2.3; 2.4; 2.5; 2.6; 2.7; 2.8; 2.9 or 3.0, preferably 0 <y "<3, particularly preferably 0 <y"<1.9,
0 ≦ w '''≦ 1, for example, w''' = 0, 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8; 0.9 or 1, preferably 0 <w '''<1,
0 ≦ w '≦ 1, for example, w' = 0, 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8; 0.9 or 1, preferably 0 <w '<1,
0 ≦ w "≦ 1, for example, w" = 0, 0.1; 0.2; 0.3; 0.4; 0.5; 0.6; 0.7; 0.8; 0.9 or 1, preferably 0 <w ''<1 and E is selected from a group comprising Eu, Ce, Yb, Mn and combinations thereof.

According to at least one embodiment, E is selected from a group comprising Eu, Ce, Yb, Mn and combinations thereof. In particular, E is Eu ²⁺ , Ce ³⁺ , Yb ³⁺ , Yb ²⁺ and / or Mn ⁴⁺ .

The metals or elements MA, MB, TA, TB, TC, TD, XC and / or XB in the case of the phosphors form the host lattice, E can be lattice sites of MA, MB, TA, TB, TC and / or TD, preferably of MA , partially replace, or take interstitial spaces.

By using the activators Eu, Ce, Yb and / or Mn, in particular Eu or Eu in combination with Ce, Yb and / or Mn, particularly well the color locus of the phosphor in the CIE color space, the peak wavelength λpeak or dominant wavelength λdom, and the Half width can be adjusted.

The dominant wavelength is one way of describing non-spectral (polychromatic) light mixtures by spectral (monochromatic) light that produces similar color perception. In the CIE color space, the line connecting a point for a particular color and the point CIE-x = 0.333, CIE-y = 0.333, can be extrapolated to meet the outline of the space in two points. The point of intersection closer to said color represents the dominant wavelength of the color as the wavelength of the pure spectral color at that point of intersection. The dominant wavelength is therefore the wavelength perceived by the human eye.

The activator E according to another embodiment in mol% amounts between 0.1 mol% to 20 mol%, 1 mol% to 10 mol%, 0.5 mol% to 5 mol%, 2 mol% to 5 mol%, to be available. Here and below,% by mole of the activator E, in particular Eu, are understood to mean molar% based on the molar proportions of MA and / or TA in the respective phosphor.

In accordance with at least one embodiment, the phosphor has one of the following general empirical formulas:
(MA) Li _3-x Si _1-x Zn _x Al _x O ₄ : E;
(MA) Li _3-x Si _1-x Mg _x Al _x O ₄ : E;
(MA) _{1-x '} Ca _x' Li ₃ Si _{1-x '} Al _x' O ₄ : E;
(MA) _{1-x "} Ca _x" Li _{3-x "} Si _1-x" Mg _{2x "} O ₄ : E;
(MA) Li _3-2z Mg _3z Si _1-z O ₄ : E;
(MA) Li ₃ Si _{1-2z '} Al _z' P _{z '} O ₄ : E.

Starting from the phosphor of the empirical formula (MA) Li ₃ SiO ₄ : E, according to at least one embodiment, LiSi may at least partially be replaced by ZnAl or MgAl and a phosphor of the formula (MA) Li _3-x Si _1-x Zn _x Al is obtained _x O ₄ : E or (MA) Li _3-x Si _1-x Mg _x Al _x O ₄ : E.

Starting from the phosphor of the empirical formula (MA) Li ₃ SiO ₄ : E, according to at least one embodiment (MA) Si may at least partially be replaced by CaAl and a phosphor of the formula (MA) _{1-x '} Ca _x' Li ₃ Si is obtained _{1-x '} Al _x' O ₄ : E.

Starting from the phosphor of the empirical formula (MA) Li ₃ SiO ₄ : E, according to at least one embodiment (MA), LiSi can be at least partially replaced by CaMg ₂ and a phosphor of the formula (MA) _{1-x "} Ca _{x '' is obtained.} Li _{3-x "} Si _1-x" Mg _{2x "} O ₄ : E.

Starting from the phosphor of the empirical formula (MA) Li ₃ SiO ₄ : E, according to at least one embodiment, Li ₂ Si may at least partially be replaced by Mg ₃ , and a phosphor of the formula (MA) Li _3-2z Mg _3z Si _{1-z is obtained} O ₄ : E.

Starting from the phosphor of the empirical formula (MA) Li ₃ SiO ₄ : E, according to at least one embodiment, Si _{2 may be} at least partially replaced by AlP and a phosphor of the formula (MA) Li ₃ Si _{1-2z '} Al _z' P _{z is obtained '} O ₄ : E.

In accordance with at least one embodiment, the phosphor has one of the following general empirical formulas:
(MA) _1-y Ca _y Li _3-2y Al _3y Si _1-y O _4-4y N _4y : E,
(MA) Li _{3- y'Al y '} SiO _4-2y' N _{2y '} : E,
(MA) Li _{3-y "} Mg _y" SiO _{4-y "} N _y" : E,
(MA) _{1-w '''} Ca _w''' Li ₃ SiO _{4-w '''} N _w''' : E,
(MA) Li _{3-w '} Al _2w' Si _{1-w '} O _4-w' N _{w '} : E,
(MA) _{1-w "} Ca _w" Li _{3-w "} Si _1-w" Al _{2w "} O _4-2w" N _{2w "} : E.

Starting from the phosphor of the empirical formula (MA) Li ₃ SiO ₄ : E, according to at least one embodiment (MA) Li ₃ SiO _{4 may} at least partially be replaced by CaLiAl ₃ N ₄ and a phosphor of the formula (MA) _1-y Ca is obtained _y Li _3-2y Al _3y Si _1-y O _4-4y N _4y : E.

Starting from the phosphor of the empirical formula (MA) Li ₃ SiO ₄ : E, according to at least one embodiment, LiO _{2 can be} at least partially replaced by AlN ₂ and a phosphor of the formula (MA) Li _{3-y '} Al _y' SiO _{4 is obtained. 2y '} N _2y' : E.

Starting from the phosphor of the empirical formula (MA) Li ₃ SiO ₄ : E, according to at least one embodiment, LiO may be at least partially replaced by MgN and a phosphor of the formula (MA) Li _{3-y "} Mg _y" SiO _{4 is obtained. y ''} N _{y ''} : E.

Starting from the phosphor of the empirical formula (MA) Li ₃ SiO ₄ : E, according to at least one embodiment (MA) O may at least partially be replaced by CaN and a phosphor of the formula (MA) _{1-w '''} Ca _{w''is obtained. '} Li ₃ SiO _4-w''' N _{w '''} : E.

Starting from the phosphor of the empirical formula (MA) Li ₃ SiO ₄ : E, according to at least one embodiment, LiSiO can be at least partially replaced by Al ₂ N and a phosphor of the formula (MA) Li _{3-w '} Al _2w' Si _{1 is obtained. w '} O _4-w' N _{w '} : E.

Starting from the phosphor of the empirical formula (MA) Li ₃ SiO ₄ : E, according to at least one embodiment (MA) Li ₃ SiO _{2 can be} at least partially replaced by CaAl ₂ N ₂ and a phosphor of the formula (MA) _{1-w 'is obtained. '} Ca _w'' Li _3-w'' Si _1-w'' Al _2w'' O _4-2w'' N _2w'' : E.

In accordance with at least one embodiment, MA is selected from a group of monovalent metals comprising Li, Na, K, Rb and combinations thereof. For example, MA can be chosen as follows: MA = Na, K, (Na, K), (Rb, Li). (Na, K), (Rb, Li) means that there is a combination of Na and K or a combination of Rb and Li. This choice of MA results in particularly efficient phosphors that are versatile.

In accordance with at least one embodiment, the phosphor has one of the following general empirical formulas:
NaLi _3-x Si _1-x Zn _x Al _x O ₄ : E,
NaLi _3-x Si _1-x Mg _x Al _x O ₄ : E,
Na _{1-x '} Ca _x' Li ₃ Si _{1-x '} Al _x' O ₄ : E,
Na _{1-x "} Ca _x" Li _{3-x "} Si _1-x" Mg _{2x "} O ₄ : E,
NaLi _3-2z Mg _3z Si _1-z O ₄ : E,
NaLi ₃ Si _{1-2z '} Al _z' P _{z '} O ₄ : E.

In accordance with at least one embodiment, the phosphor has one of the following general empirical formulas:
(Na _r K _1-r ) ₁ Li _3-x Si _1-x Zn _x Al _x O ₄ : E,
(Na _r K _1-r ) ₁ Li _3-x Si _1-x Mg _x Al _x O ₄ : E,
(Na _r K _1-r ) _{1-x '} Ca _x' Li ₃ Si _{1-x '} Al _x' O ₄ : E,
(Na _r K _1-r ) _{1-x "} Ca _x" Li _{3-x "} Si _1-x" Mg _{2x "} O ₄ : E,
(Na _r K _1-r ) ₁ Li _3-2z Mg _3z Si _1-z O ₄ : E,
(Na _r K _1-r ) ₁ Li ₃ Si _{1-2z '} Al _z' P _{z '} O ₄ : E, where
0 ≤ r ≤ 1, for example, r = 0; 0.05; 0.1; 0.15; 0.2; 0.25; 0.3; 0.35, 0.4; 0.45; 0.5; 0.55; 0.6; 0.65; 0.7; 0.75; 0.8; 0.85; 0.9; 0.95; 1.0. Preferably, 0 ≤ r ≤ 0.1 or 0.1 ≤ r ≤ 0.4 or 0.4 ≤ r ≤ 1.0; particularly preferably r = 0, 0.25, 0.5 or 1.0.

In accordance with at least one embodiment, the phosphor has one of the following general empirical formulas:
(Rb _{r '} Li _1-r' ) ₁ Li _3-x Si _1-x Zn _x Al _x O ₄ : E,
(Rb _{r '} Li _1-r' ) ₁ Li _3-x Si _1-x Mg _x Al _x O ₄ : E,
(Rb _{r '} Li _1-r' ) _{1-x '} Ca _x' Li ₃ Si _{1-x '} Al _x' O ₄ : E,
(Rb _{r '} Li _1-r' ) _{1-x "} Ca _x" Li _{3-x "} Si _1-x" Mg _{2x "} O ₄ : E,
(Rb _{r '} Li _1-r' ) ₁ Li _3-2z Mg _3z Si _1-z O ₄ : E,
(Rb _{r '} Li _1-r' ) ₁ Li ₃ Si _{1-2z '} Al _z' P _{z '} O ₄ : E, where 0 ≤ r' ≤ 1,
for example, r '= 0; 0.05; 0.1; 0.15; 0.2; 0.25; 0.3; 0.35, 0.4; 0.45; 0.5; 0.55; 0.6; 0.65; 0.7; 0.75; 0.8; 0.85; 0.9; 0.95; 1.0, preferably 0.25 ≦ r '≦ 0.75, more preferably 0.4 ≦ r' ≦ 0.6, most preferably r '= 0.5.

In accordance with at least one embodiment, the phosphor has one of the following general empirical formulas:
(Na _r K _1-r ) _1-y Ca _y Li _3-2y Al _3y Si _1-y O _4-4y N _4y : E,
(Na _r K _1-r ) Li _{3- y'Al y '} SiO _4-2y' N _{2y '} : E,
(Na _r K _1-r ) Li _{3-y "} Mg _y" SiO _{4-y "} N _y" : E,
(Na _r K _1-r ) _{1-w '''} Ca _w''' Li ₃ SiO _{4-w '''} N _w : E,
(Na _r K _1-r ) Li _{3-w '} Al _2w' Si _{1-w '} O _4-w' N _{w '} : E,
(Na _r K _1-r ) _{1-w "} Ca _w" Li _{3-w "} Si _1-w" Al _{2w "} O _4-2w" N _{2w "} : E, where
0 ≤ r ≤ 1, for example, r = 0; 0.05; 0.1; 0.15; 0.2; 0.25; 0.3; 0.35, 0.4; 0.45; 0.5; 0.55; 0.6; 0.65; 0.7; 0.75; 0.8; 0.85; 0.9; 0.95; 1.0. Preferably, 0 ≤ r ≤ 0.1 or 0.1 ≤ r ≤ 0.4 or 0.4 ≤ r ≤ 1.0; particularly preferably r = 0, 0.25, 0.5 or 1.0.

In accordance with at least one embodiment, the phosphor has one of the following general empirical formulas:
(Rb _{r '} Li _1-r' ) _1-y Ca _y Li _3-2y Al _3y Si _1-y O _4-4y N _4y : E,
(Rb _{r '} Li _1-r' ) Li _{3-y '} Al _y' SiO _{4-2y '} N _2y' : E,
(Rb _{r '} Li _1-r' ) Li _{3-y "} Mg _y" SiO _{4-y "} N _y" : E,
(Rb _{r '} Li _1-r' ) _{1-w '''} Ca _w''' Li ₃ SiO _{4-w '''} N _w : E,
(Rb _{r '} Li _1-r' ) Li _{3-w '} Al _2w' Si _{1-w '} O _4-w' N _{w '} : E,
(Rb _{r '} Li _1-r' ) _{1-w ''} Ca _{w ''} Li _{3-w ''} Si _{1-w ''} Al _{2w ''} O _{4-2w ''} N _{2w ''} : E, where
where 0 ≤ r '≤ 1, for example r' = 0; 0.05; 0.1; 0.15; 0.2; 0.25; 0.3; 0.35, 0.4; 0.45; 0.5; 0.55; 0.6; 0.65; 0.7; 0.75; 0.8; 0.85; 0.9; 0.95; 1.0, preferably 0.25 ≦ r '≦ 0.75, more preferably 0.4 ≦ r' ≦ 0.6, most preferably r '= 0.5.

In accordance with at least one embodiment, the phosphor has one of the following general empirical formulas:
Na _1-y Ca _y Li _3-2y Al _3y Si _1-y O _4-4y N _4y : E,
NaLi _3- y'Al _{y '} SiO _{4-2y'N 2y'} : E,
NaLi _{3-y "} Mg _y" SiO _{4-y "} N _y" : E,
Na _{1-w '''} Ca _w''' Li ₃ SiO _{4-w '''} N _w : E,
NaLi _{3-w '} Al _2w' Si _{1-w '} O _4-w' N _{w '} : E,
Na _{1-w "} Ca _w" Li _{3-w "} Si _1-w" Al _{2w "} O _4-2w" N _{2w "} : E.

In accordance with at least one embodiment, the phosphor has the general empirical formula (MA) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E. Here, MA is selected from a group of monovalent metals comprising Li, Na, K, Rb, Cs, Cu, Ag and combinations thereof. Preferably, MA is selected from a group of monovalent metals comprising Li, Na, K, Rb and combinations thereof. TA is selected from a group of monovalent metals comprising Li, Na, Cu, Ag and combinations thereof. TD is selected from a group of tetravalent metals comprising Si, Ge, Sm, Mn, Ti, Zr, Hf, Ce, and combinations thereof. XB is selected from a group of elements comprising O, S and combinations thereof. E is selected from a group comprising Eu, Ce, Yb, Mn and combinations thereof. In particular, E occupies the lattice sites of MA. For charge equalization, the proportion of further elements, for example TA and / or TD, may change. For example, E = Eu ²⁺ and replaces MA ⁺ , the charge compensation takes place via a change in the proportion of TA and / or TD.

In accordance with at least one embodiment, the phosphor has the general empirical formula (MA) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E. In this case, MA is selected from a group of monovalent metals comprising Li, Na, K, Rb and combinations thereof. TA = Li, TD = Si, XB = O and E is selected from a group comprising Eu, Ce, Yb, Mn and combinations thereof. Preferably, E = Eu or a combination of Eu with Ce, Yb and / or Mn.

Surprisingly, it has been found that by varying the composition of MA, the properties of the phosphor, in particular with regard to the peak wavelength and the half-width, can be changed considerably. In addition, the phosphors have a high absorption capacity of primary radiation in the range of 300 nm to 460 nm or 300 nm to 500 nm, in particular between 300 nm and 450 nm or 300 nm and 430 nm.

For example, the phosphor of the formula NaLi ₃ SiO ₄ : Eu emits when excited with a primary radiation having a wavelength of 400 nm in the blue spectral range of the electromagnetic spectrum and shows a narrow-band emission, that is an emission with a low half-width. In the case of an excitation with a primary radiation having a wavelength of 400 nm, on the other hand, the phosphor of the formula KLi ₃ SiO ₄ : Eu emits very broadband from the blue to red spectral range, so that a white-colored light impression is produced. The phosphor of the formula (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu emitted narrow band in the blue-green spectral range of the electromagnetic spectrum and the phosphors of the formula (Rb _0.5 Li _0.5 ) Li ₃ SiO ₄ : Eu and (Na _0.25 K _0.75 ) Li ₃ SiO ₄ : Eu emit narrow band in the green spectral range of the electromagnetic spectrum. The following table shows the properties of the phosphors: λprim λpeak λdom FWHM NaLi ₃ SiO ₄ : Eu 400 nm 469 nm 473 nm 32 nm KLi ₃ SiO ₄ : Eu 400 nm - - - (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu 400 nm 486 nm 493 nm 19.2 nm (Rb _0.5 Li _0.5 ) Li ₃ SiO ₄ : Eu 400 nm 528 nm 538.7 nm 42.8 nm (Na _0.25 K _0.75 ) Li ₃ SiO ₄ : Eu 400 nm 529 nm 541.4 nm 45 nm

Due to the different emission properties, the phosphors are suitable for a wide variety of applications.

The blue spectral range is understood to be the range of the electromagnetic spectrum between 420 nm and 520 nm.

The green spectral range is understood to be the range of the electromagnetic spectrum between 520 nm and 580 nm inclusive.

In accordance with at least one embodiment, the phosphor has the general empirical formula (Na _r K _{1 -r} ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E, 0 ≦ r ≦ 1, for example r = 0; 0.05; 0.1; 0.15; 0.2; 0.25; 0.3; 0.35, 0.4; 0.45; 0.5; 0.55; 0.6; 0.65; 0.7; 0.75; 0.8; 0.85; 0.9; 0.95; 1.0. Preferably, 0 ≤ r ≤ 0.1 or 0.1 ≤ r ≤ 0.4 or 0.4 ≤ r ≤ 1.0; particularly preferably r = 0, 0.25, 0.5 or 1.0. Surprisingly, the properties of the phosphor, in particular the peak wavelength and the half-width, change with a variation of the proportions of Na and K in the phosphor. As a result, a wide variety of applications can be used by these phosphors.

According to at least one embodiment, the phosphor has the formula (Na _r K _{1 -r} ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.4 <r ≦ 1, preferably 0.45 <r ≦ 1, very particularly preferably r = 0.5 or 1. Preferably, TA = Li, TD = Si and XB = O. For example, the phosphor has the formula NaLi ₃ SiO ₄ : Eu or (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu. The peak wavelength of the phosphor lies in the blue spectral range, in particular in the range between 450 nm and 500 nm.

The phosphor (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.4 <r ≦ 1, for example NaLi ₃ SiO ₄ : Eu or (Na _0.5 K _{0, 5} ) Li ₃ SiO ₄ : Eu is particularly suitable for use in conversion LEDs that emit white radiation. For this purpose, the phosphor can be combined with a red and green phosphor.

In addition, the phosphor (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.4 <r ≦ 1, in particular (Na _0.5 K _0.5 ) Li ₃ is suitable SiO ₄ : Eu for use in lighting devices such as conversion LEDs that emit blue radiation.

In accordance with at least one embodiment, the phosphor has the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E where 0 ≦ r ≦ 0.15, preferably 0 ≦ r ≦ 0.1, especially preferably r = 0. Preferably, TA = Li, TD = Si and XB = O. For example, the phosphor KLi ₃ SiO ₄ : Eu. The phosphor emits very broadband from the blue to the red spectral range, so that a white light impression is created.

The phosphor (Na _r K _{1 -r} ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E where 0 ≦ r ≦ 0.15, in particular KLi ₃ SiO ₄ : Eu is suitable, for example, for use in lighting devices such as Conversion LEDs that emit white radiation. Due to the broad emission of the phosphor, this can be used with advantage as the only phosphor in a lighting devices such as a conversion LED.

In accordance with at least one embodiment, the phosphor has the general empirical formula (Rb _{r '} Li _1-r' ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E, where 0 ≦ r '≦ 1, for example r' = 0 ; 0.05; 0.1; 0.15; 0.2; 0.25; 0.3; 0.35, 0.4; 0.45; 0.5; 0.55; 0.6; 0.65; 0.7; 0.75; 0.8; 0.85; 0.9; 0.95; 1.0, preferably 0.25 ≦ r '≦ 0.75, more preferably 0.4 ≦ r' ≦ 0.6, most preferably r '= 0.5. It has been found that these phosphors have a low half-width and are versatile.

In accordance with at least one embodiment, the phosphor has the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.1 <r ≦ 0.4, preferably 0.15 <r ≦ 0.35, more preferably 0.2 <r ≦ 0.3, most preferably r = 0.25 or (Rb _{r '} Li _1-r' ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0 ≦ r '≦ 1, preferably 0.25 ≦ r' ≦ 0.75, particularly preferably 0.4 ≦ r '≦ 0.6. Preferably, TA = Li, TD = Si and XB = O. The peak wavelength of the phosphor is in the green spectral range and has a half-width of less than 50 nm.

Surprisingly, the phosphors according to the invention (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.1 <r ≦ 0.4 and (Rb _{r '} Li _1-r' ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0 ≤ r '≤ 1, for example (Rb _0.5 Li _0.5 ) Li ₃ SiO ₄ : Eu and (Na _0.25 K _0.75 ) Li ₃ SiO ₄ : Eu a peak wavelength in the green spectral range and a very small half width and are therefore particularly for white-emitting illumination devices such as white-emitting conversion LEDs in conjunction with a blue primary radiation emitting semiconductor chip and a red phosphor for backlighting applications, especially for display elements such Displays suitable. Advantageously, with such a white-emitting, in particular such a conversion LED, a particularly wide range of colors can be achieved. Due to the low half-width of the phosphors according to the invention
(Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.1 <r ≤ 0.4 and
(Rb _{r '} Li _1-r' ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E where 0 ≤ r '≤ 1, for example
(Rb _0.5 Li _0.5 ) Li ₃ SiO ₄ : Eu and (Na _0.25 K _0.75 ) Li ₃ SiO ₄ : Eu show the emission peaks a very large overlap with the transmission range of a standard green filter, so that only little light is lost and the achievable color space is large.

In accordance with at least one embodiment, the phosphor crystallizes in a crystal structure having the same atomic sequence as in UCr ₄ C ₄ , CsKNa ₂ Li ₁₂ Si ₄ O ₁₆ or RbLi ₅ {Li [SiO ₄ ]} ₂ . That the phosphor crystallizes in a crystal structure with the same atomic sequence as in UCr ₄ C ₄ , CsKNa ₂ Li ₁₂ Si ₄ O ₁₆ or RbLi ₅ {Li [SiO ₄ ]} ₂ means here and in the following that the sequence of the atoms of the phosphor follows the same pattern as the sequence of atoms in UCr ₄ C ₄ , CsKNa ₂ Li ₁₂ Si ₄ O ₁₆ or RbLi ₅ {Li [SiO ₄ ]} ₂ . In other words, the crystal structure shows the same structural motifs as UCr ₄ C ₄ , CsKNa ₂ Li ₁₂ Si ₄ O ₁₆ or RbLi ₅ {Li [SiO ₄ ]} ₂ . For example, the phosphor of the formula (Na _0.5 K _0.5 ) Li ₃ SiO ₃ : Eu crystallizes in a crystal structure with the same atomic sequence as in CsKNa ₂ Li ₁₂ Si ₄ O ₁₆ , where K occupies the sites of the Cs and the K, Na the places of the Na, Li the places of the Li, Si the places of the Si and O the places of the O. By the variation of the ionic radii with the substitution with other atomic places the absolute position (atomic coordinates) of the atoms can change.

The phosphor can also crystallize in a crystal structure with the same atomic sequence as in the structures derived from UCr ₄ C ₄ NaLi ₃ SiO ₄ or KLi ₃ GeO ₄ .

• – NaLi₃SiO₄
• – KLi₃SiO₄
• – RbLi₅{Li[SiO₄]}₂
• – UCr₄C₄
• – CsKNa₂Li₁₂Si₄O₁₆ oder
• – CsKNaLi₉{Li[SiO₄]}₄.

In accordance with at least one embodiment, the phosphor crystallizes in the same structural type as

• NaLi ₃ SiO ₄
• - KLi ₃ SiO ₄
• - RbLi ₅ {Li [SiO ₄ ]} ₂
• - UCr ₄ C ₄
• - CsKNa ₂ Li ₁₂ Si ₄ O ₁₆ or
• - CsKNaLi ₉ {Li [SiO ₄ ]} ₄ .

The crystal structures of the embodiments are characterized in particular by a three-dimensionally linked spatial network. In this case, TA, TB, TC, TD, TE and / or TF are surrounded by XA, XB, XC and / or XD, and the resulting assemblies are linked via common corners and edges. This arrangement results in a three-dimensionally extending anionic substructure. In the resulting cavities MA, MB, MC and / or MD are arranged.

In accordance with at least one embodiment, the phosphor has a crystal structure in which TA, TB, TC, TD, TE and / or TF are surrounded by XA, XB, XC and / or XD and the resulting assemblies are distributed over common corners and edges a three-dimensional network of space with cavities are linked and are arranged in the cavities MA, MB, MC and / or MD.

For example, in the crystal structure of the embodiment, KLi ₃ SiO ₄ : E, which is iso-type to KLi ₃ GeO ₄ , Li and Si are surrounded by O and form the anionic substructure in the form of a space network of distorted (Li / Si) O ₄ tetrahedra. In the resulting cavities, the K atoms are distorted cube-shaped surrounded by 8 O atoms.

In the crystal structure of the embodiment RbLi ₅ {Li [SiO ₄ ]} ₂ : E, part of the Li atoms and Si are surrounded by O and form the anionic substructure in the form of a space network. The Si atoms are distorted tetrahedrally surrounded by 4 O atoms. The Li atoms involved in the substructure are distorted in their first coordination sphere trigonal planar surrounded by 3 O atoms. With the addition of additional O atoms in the environment, the coordination can also be described as distorted tetrahedral or distorted trigonal bipyramidal. In the resulting cavities, the Rb atoms are distorted cube-like surrounded by 8 O atoms, while the other part of the Li atoms is distorted square planar surrounded by 4 O atoms.

Depending on the chemical composition of the phosphors disclosed herein, there may be a strong distortion of the coordination sphere around MA, MB, MC and / or MD. This leads, for example, in the case of the exemplary embodiment NaLi ₃ SiO ₄ : E, to the fact that the environment of the Na atoms is present as a distorted trigonal prism or with the addition of a further O atom as a distorted clipped cube.

The specified embodiments of the phosphor can be prepared according to the following methods. All features described for the phosphor thus also apply to the process for its preparation and vice versa.

A method for producing a phosphor is given.

• – e + f + g + h + i + j = u
• – k + l + m + n = v
• – a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j – k – 2l – 3m – 4n = w
• – 0.8 ≤ t ≤ 1
• – 3.5 ≤ u ≤ 4
• – 3.5 ≤ v ≤ 4
• – (–0.2) ≤ w ≤ 0.2. Bevorzugt gilt: 0 ≤ m < 0,875 v und/oder v ≥ l > 0,125 v.

In accordance with at least one embodiment, the phosphor has the general empirical formula: (MA) _a (MB) _b (MC) _c (MD) _d (TA) _e (TB) _f (TC) _g (TD) _h (TE) _i (TF () _j XA) _k (XB) _l (XC) _m (XD) _n. Here, MA is selected from the group of monovalent metals, MB is selected from a group of divalent metals, MC is selected from a group of tri-valent metals, MD is selected from a group of tetravalent metals, TA is selected from a group of monovalent metals, TB is selected from a group of divalent metals, TC is selected from a group of trivalent metals, TD is selected from a group of tetravalent metals, TE is selected from a group of pentavalent elements, TF is selected from a group of hexavalent elements, XA is selected from a group of elements comprising halogens, XB is selected from a group of elements comprising O, S and combinations thereof, XC = N and XD = C. Next:
a + b + c + d = t;

• - e + f + g + h + i + j = u
• - k + 1 + m + n = v
• - a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j - k - 2l - 3m - 4n = w
• - 0.8 ≤ t ≤ 1
• - 3.5 ≤ u ≤ 4
• - 3.5 ≤ v ≤ 4
• - (-0.2) ≤ w ≤ 0.2. Preferably, 0 ≤ m <0.875 v and / or v ≥ l> 0.125 v.

• A) Vermengen von Edukten des Leuchtstoffs,
• B) Aufheizen des unter A) erhaltenen Gemenges auf eine Temperatur T1 zwischen 500 und 1400 °C, bevorzugt zwischen 700 und 1400 °C,
• C) Glühen des Gemenges bei einer Temperatur T1 von 500 bis 1400 °C, bevorzugt zwischen 700 und 1400 °C, für 0,5 Minuten bis zehn Stunden.

The method comprises the following method steps:

• A) mixing of educts of the phosphor,
• B) heating the mixture obtained under A) to a temperature T1 between 500 and 1400 ° C, preferably between 700 and 1400 ° C,
• C) annealing the batch at a temperature T1 of 500 to 1400 ° C, preferably between 700 and 1400 ° C, for 0.5 minutes to ten hours.

In one embodiment, the starting materials are present as a powder.

• D) Abkühlen des Gemenges auf Raumtemperatur. Unter Raumtemperatur werden insbesondere 20 °C verstanden.

In one embodiment, after method step C), a further method step follows:

• D) Cool the mixture to room temperature. By room temperature is meant in particular 20 ° C.

In one embodiment, process steps B) and C) are followed by process step D), in which case the phosphor obtained in process step D) is heated or annealed. By this further annealing process, the optical properties of the phosphor can be improved.

In accordance with at least one embodiment, the educts melt during the heating of the batch obtained under A) in process step B).

For example, the cooling and cooling rates can be at 250 ° C per hour.

In one embodiment, the process steps B), C) and / or D) take place under a forming gas atmosphere. Preferably, in the forming gas, the ratio of nitrogen: hydrogen is 92.5: 7.5.

In one embodiment, the process steps B), C) and / or D) take place in a tube furnace.

• A) Vermengen der Edukte umfassend K₂CO₃, Na₂CO₃ und/oder RbCO₃.

In accordance with at least one embodiment, the method comprises the following method step A):

• A) mixing the starting materials comprising K ₂ CO ₃ , Na ₂ CO ₃ and / or RbCO ₃ .

• A) Vermengen der Edukte umfassend oder bestehend aus SiO₂, Eu₂O₃, Li₂CO₃ und zumindest ein Carbonat aus K₂CO₃, Na₂CO₃ und RbCO₃.

In accordance with at least one embodiment, the method comprises the following method step A):

• A) mixing the starting materials comprising or consisting of SiO ₂ , Eu ₂ O ₃ , Li ₂ CO ₃ and at least one carbonate of K ₂ CO ₃ , Na ₂ CO ₃ and RbCO ₃ .

The manufacturing process is very easy to perform compared to many other phosphor production processes. In particular, no inert gas atmosphere is required since neither the starting materials nor the products are sensitive to moisture or oxygen. In addition, the synthesis takes place at moderate temperatures and is therefore very energy efficient. The requirements, for example, the oven used are so low. The educts are inexpensive commercially available and non-toxic.

In accordance with at least one embodiment, the illumination device, in particular the conversion LED, emits white radiation during operation. The radiation can be composed of a superposition of the primary radiation and the secondary radiation or only of the secondary radiation.

According to at least one embodiment, the phosphor emits a secondary radiation having a peak wavelength in the blue spectral range of the electromagnetic spectrum. In order to produce a total white radiation, the conversion element may comprise a second and a third phosphor. In particular, the second phosphor can be set up to partially convert the electromagnetic primary radiation into an electromagnetic secondary radiation which lies in the red spectral range of the electromagnetic spectrum during operation of the illumination device. In particular, the third phosphor can be set up to partially convert the electromagnetic primary radiation into an electromagnetic secondary radiation which lies in the green spectral range of the electromagnetic spectrum during operation of the illumination device. A superposition of the blue, green and red secondary radiation produces a white luminous impression. The lighting device, in particular the conversion LED according to this embodiment is particularly suitable for general lighting.

The blue spectral range is understood to be the range of the electromagnetic spectrum between 420 nm and 520 nm.

The green spectral range is understood to be the range of the electromagnetic spectrum between 520 nm and 580 nm inclusive.

The red spectral range is understood to be the range of the electromagnetic spectrum between 630 nm and 780 nm.

The conversion of the UV or blue primary radiation into a secondary radiation with a slightly longer wavelength in the blue region of the electromagnetic spectrum increases the efficiency of the illumination device, in particular the conversion LED. The peak wavelength of the secondary radiation is closer to the maximum of the eye sensitivity at 555 nm compared to the primary radiation, whereby the emitted radiation has a higher overlap with the eye sensitivity curve and is therefore perceived as lighter.

In accordance with at least one embodiment, the phosphor emits secondary radiation having a peak wavelength in the green spectral range of the electromagnetic spectrum. In order to produce a total white radiation, the conversion element may comprise a second phosphor, which may be configured to partially convert the electromagnetic primary radiation into an electromagnetic secondary radiation in the red spectral region of the electromagnetic spectrum during operation of the illumination device. A superimposition of the blue primary radiation and the green and red secondary radiation produces a white light impression. The lighting device, in particular the conversion LED according to this embodiment is particularly suitable for backlighting applications.

The third phosphor having a peak wavelength in the green spectral region may be selected from a group comprising β-SiAlONs, α-SiAlONs, chlorosilicates, orthosilicates, silicon oxide nitrides (SiONe), garnets, and combinations thereof.

The garnet phosphor may according to one embodiment be selected from the material system (Y, Lu, Gd, Ce) ₃ (Al, Ga) ₅ O ₁₂ or (Y, Lu, Gd, Ce) ₃ (Al) ₅ O ₁₂ . The garnet phosphor is preferably selected from the material system (Y, Lu, Ce) ₃ Al ₅ O ₁₂ and (Y, Lu, Ce) ₃ (Al, Ga) ₅ O ₁₂ . For example, the phosphor Y ₃ Al ₅ O _12.

The α-SiAlONs may, for example, have the following empirical formula: M _t Si _{12- (t '+ t'')} Al _{(t' + t '')} O _n N _16-n : Eu with M = Ca, Mg, Y, preferred approximately

The chlorosilicates may, for example, have the following empirical formula: (Ca, Sr, Ba, Eu) ₈ Mg (SiO ₄ ) ₄ Cl ₂ .

The silicon oxynitrides may have, for example, the following empirical formula:
(EA * _{1-t '''} Eu _t''' ) Si ₂ O ₂ N ₂ with 0 <t '''≤0.2, preferably 0 <t''' ≤0.15, particularly preferably 0.02 ≤t '''≤0.15 and EA * = Sr, Ca, Ba and / or Mg. Preferred is (Sr _{1-t''' - o} EA * _o Eu _{t '''} ) Si ₂ O ₂ N ₂ with EA * = Ba, Ca and / or Mg and 0 ≤ o <0.5.

The second phosphor having a peak wavelength in the red spectral range may be, for example, a nitridosilicate or a nitridoaluminate. In particular, the nitridosilicate may be selected from the material systems (Ca, Sr, Ba, Eu) ₂ (Si, Al) ₅ (N, O) ₈ , (Ca, Sr, Ba, Eu) AlSi (N, O) ₃ , ( Ca, Sr, Ba, Eu) AlSi (N, O) ₃ .Si ₂ N ₂ O, (Ca, Sr, Ba, Eu) ₂ Si ₅ N ₈ , (Ca, Sr, Ba, Eu) AlSiN ₃ and combinations it. The nitridoaluminate may have the formula MLiAl ₃ N ₄ : Eu (M = Ca, Sr).

Furthermore, the second phosphor can be selected from a material system with a peak wavelength in the red spectral range, which is disclosed in the patent application WO2015 / 052238A1 is described, the disclosure of which is hereby incorporated in full in this respect by reference. For example, the second phosphor has the formula Sr (Sr, Ca) Si ₂ Al ₂ N ₆ : Eu.

The second phosphor having a peak wavelength in the red spectral range may also be a phosphor having the empirical formula A ₂ [SiF ₆ ]: Mn ⁴⁺ with A = Li, Na, K, Rb, Cs, for example K ₂ SiF ₆ : Mn ⁴⁺ .

The second phosphor having a peak wavelength in the red spectral region may also be Mg ₄ GeO _5.5 F: Mn.

In accordance with at least one embodiment, the illumination device, in particular the conversion LED, is configured to emit white radiation. The phosphor has the formula (Na _r K _{1 -r} ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E where 0 ≦ r ≦ 0.1, preferably 0 ≦ r ≦ 0.15, particularly preferably r = 0, up. Preferably, TA = Li, TD = Si and XB = O. For example, the phosphor KLi ₃ SiO ₄ : Eu. The phosphor emits very broadband from the blue to red spectral range, so that a white-colored light impression is created. Advantageously, it is possible that the conversion element consists of this phosphor or this phosphor and the matrix material. In particular, the conversion element or the illumination device, in particular the conversion LED according to this embodiment, has no further phosphor. The phosphor can therefore be present as the only phosphor in the conversion element or the illumination device, in particular the conversion LED. The lighting device, in particular the conversion LED has a high efficiency and a high color rendering index. In particular, the illumination device, in particular the conversion LED according to this embodiment, emits warm white radiation having a color temperature below 3500 K, in particular below 3000 K. Thus, this illumination device, in particular this conversion LED, is particularly suitable for general illumination.

In comparison to known white-emitting conversion LEDs, which use a blue-emitting semiconductor chip and a red and green phosphor to generate white light, the elaborate binning of the semiconductor chips can be dispensed with here, or this can be carried out at least with a larger tolerance. It is possible to use semiconductor chips which have a primary radiation which is not or barely perceived by the human eye (300 nm to 430 nm or 440 nm). Manufacturing, temperature or Durchlassstrombedingte fluctuations in the primary radiation have no negative impact on the overall radiation properties. Compared to the use of two or more phosphors, no color matching by varying the concentrations of the phosphors is necessary because the emission spectrum of only one phosphor is generated and thus constant. The conversion LEDs can be manufactured with high throughput, since no color matching or complex chip binning is necessary. There are no color shifts or other negative effects on the emission spectrum due to selective degradation of only one phosphor. Depending on the application, partial conversion of the primary radiation can also take place. Since it is possible to excite the phosphor with a primary radiation in the range of 300 nm to 430 nm or 440 nm, a contribution of the primary radiation, preferably in the short-wave blue region of the electromagnetic spectrum, to the total radiation results in objects illuminated thereby becoming whiter, more radiant and therefore more attractive. Thus, for example, optical brighteners in textiles can be stimulated.

In accordance with at least one embodiment, the illumination device, in particular the conversion light-emitting diode, is configured to emit white radiation, the phosphor having the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.1 <r ≦ 1, preferably 0.15 <r ≦ 1 or (Rb _{r '} Li _1-r' ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0 ≦ r '≦ 1, preferably 0.25 ≦ r '≦ 0.75, particularly preferably 0.4 ≦ r' ≦ 0.6. Preferably, TA = Li, TD = Si and XB = O. The conversion element comprises at least a second phosphor, which is adapted to convert the electromagnetic primary radiation during operation of the lighting device, in particular the conversion LED partially into an electromagnetic secondary radiation in the red spectral range of the electromagnetic spectrum.

In accordance with at least one embodiment, the phosphor has the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.1 <r ≦ 0.4, preferably 0.15 <r ≦ 0.35, more preferably 0.2 <r ≦ 0.3, most preferably r = 0.25 or (Rb _{r '} Li _1-r' ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0 ≦ r '≦ 1, preferably 0.25 ≦ r' ≦ 0.75, particularly preferably 0.4 ≦ r '≦ 0.6. Preferably, TA = Li, TD = Si and XB = O. The peak wavelength of the phosphor is preferably in the green spectral range and has a half-width of less than 50 nm. The conversion element comprises a second phosphor, which is set up to partially convert the electromagnetic primary radiation into an electromagnetic secondary radiation which lies in the red spectral region of the electromagnetic spectrum during operation of the illumination device. It is possible that the conversion element consists of the phosphor and the second phosphor or of the phosphor, the second phosphor and the matrix material. In particular, the conversion element or the conversion LED according to this embodiment has no further phosphor. The phosphor and the second phosphor can thus be present as the only phosphors in the conversion element or the lighting device, in particular the conversion LED. A superposition of the primary radiation and the secondary radiation in the red and green spectral range gives rise to a white-colored luminous impression.

Advantageously, with a lighting device, in particular with a conversion LED according to this embodiment, a particularly wide range of colors can be reproduced. So it is suitable the lighting device, in particular the conversion LED according to this embodiment, in particular for backlighting applications for display elements such as displays.

For liquid crystal displays (LCDs) and other displays, the colors are represented by the primary colors red, green, and blue. The range of colors that can be reproduced on a display is therefore limited by the spanned color triangle of the colors red, green and blue. These colors are filtered out accordingly by the backlighting spectrum of red, green and blue color filters. However, the wavelength range of the transmitted radiation of the color filters is still very wide. Therefore, light sources with very narrow band emissions, ie a low half width, in the green, blue and red spectral range are needed to cover the widest possible color space. As light sources for backlighting applications, a blue-emitting semiconductor chip with a phosphor having a peak wavelength in the green and a phosphor having a peak wavelength in the red spectral range are predominantly combined, the phosphors having the lowest possible half-width of the emission. Ideally, the emission peaks are congruent with the transmission range of the respective color filter in order to lose as little light as possible, to achieve the maximum efficiency and to reduce crosstalk or overlapping of the different color channels, which limits the achievable color space.

Due to the low half-width of the phosphors according to the invention (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.1 <r ≦ 0.4 or (Rb _{r '} Li _1-r' ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0 ≦ r '≦ 1, for example (Rb _0.5 Li _0.5 ) Li ₃ SiO ₄ : Eu or (Na _0.25 K _{0, 75} ) Li ₃ SiO ₄ : Eu, the emission peaks show a very large overlap with the transmission range of a standard green filter (with a half-width in the range of typically 70 to 120 nm), so that only little light is lost and the achievable color space is large. Specifically, as the second phosphor, a phosphor having a narrow half-width, such as K ₂ SiF ₆ : Mn, Mg ₄ GeO ₅ .5 F: Mn, SrLiAl ₃ N ₄ : Eu or Sr (Sr, Ca) Si ₂ Al ₂ N ₆ : Eu used. In particular, the combination of a green and a red phosphor with low half-width results in the coverage of a large color space.

In accordance with at least one embodiment, the illumination device, in particular the conversion light-emitting diode, is configured to emit green radiation, the phosphor has the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.1 <r ≦ 0.4, preferably 0.15 <r ≦ 0.35, more preferably 0.2 <r ≦ 0.3, most preferably r = 0.25 or (Rb _{r '} Li _{1 -r '} ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0 ≦ r' ≦ 1, preferably 0.25 ≦ r '≦ 0.75, particularly preferably 0.4 ≦ r' ≦ 0, 6, up. Preferably, TA = Li, TD = Si and XB = O. The peak wavelength of the phosphor is in the green spectral range and has a half-width of less than 50 nm. It is possible that the conversion element consists of this phosphor or this phosphor and the matrix material. In particular, the conversion element or the illumination device, in particular the conversion LED according to this embodiment, has no further phosphor. The phosphor can therefore be present as the only phosphor in the conversion element or the illumination device, in particular the conversion LED.

Green light-emitting diodes which emit radiation in the green wavelength range can be obtained firstly by directly green-emitting semiconductor chips or conversion LEDs with a semiconductor chip and a green phosphor. Direct green emitting semiconductor chips show a very low quantum efficiency. With the conversion LEDs, the primary radiation can be completely converted into green secondary radiation (full conversion) or partly converted into green secondary radiation (partial conversion) and the remaining amount of green radiation is filtered out by means of a filter.

Conventionally, (Y, Lu) ₃ (Al, Ga) ₅ O ₁₂ : Ce, orthosilicates or oxonitrido-orthosilicates are used as green phosphors. The conventional conversion LEDs often have low efficiency and color purity. To overcome these disadvantages, filters are used to adjust the emission. However, this has a negative effect on the overall performance of the conversion LED.

Illumination devices, in particular conversion LEDs with the green phosphor according to the invention of the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.1 <r ≦ 0.4 or (Rb _{r '} Li _1-r' ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E where 0 ≤ r '≤ 1, for example, (Rb _0.5 Li _0.5 ) Li ₃ SiO ₄ : Eu and (Na _0.25 K _0.75 ) Li ₃ SiO ₄ : Eu, on the other hand, are very efficient and show high color purity and high performance even without the use of a color filter.

In accordance with at least one embodiment, the illumination device, in particular the conversion light-emitting diode, is configured to emit white radiation. The phosphor has the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.4 <r ≦ 1, preferably 0.45 <r ≦ 1, most preferably r = 0, 5 or 1, on. Preferably, TA = Li, TD = Si and XB = O. For example, the phosphor has the formula NaLi ₃ SiO ₄ : Eu or (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu. The peak wavelength of the phosphor is preferably in the blue spectral range, in particular in the range between 450 nm and 500 nm. The conversion element comprises a second and a third phosphor, wherein the second phosphor is adapted to partially convert the electromagnetic primary radiation into an electromagnetic secondary radiation which is in the red spectral range of the electromagnetic spectrum, and the third phosphor is adapted to convert the electromagnetic primary radiation in the operation of the lighting device into a secondary electromagnetic radiation, which is in the green spectral range of the electromagnetic spectrum. It is possible that the conversion element consists of the phosphor, the second and third phosphor or of the phosphor, the second and the third phosphor and the matrix material. In particular, the conversion element or the illumination device, in particular the conversion LED according to this embodiment, has no further phosphor. The phosphor and the second and third phosphors can therefore be present as the only phosphors in the conversion element or the illumination device, in particular the conversion LED. A superposition of the secondary radiations in the blue, red and green spectral range gives rise to a white-colored luminous impression. The lighting device, in particular conversion LED according to this embodiment is particularly suitable for general lighting.

Known white-emitting conversion LEDs use a semiconductor chip which emits a blue primary radiation and a red and green phosphor. Overlaying the blue primary radiation and the red and green secondary radiation produces white light. A disadvantage of this solution is that the epitaxially grown semiconductor chips, based for example on GaN or InGaN, may exhibit fluctuations in the peak wavelength of the emitted primary radiation. This leads to fluctuations in the total white radiation, such as a change of the color location and the color reproduction, since the primary radiation contributes the blue component to the total radiation. This is particularly problematic in the use of multiple semiconductor chips in a device. To prevent fluctuations, the semiconductor chips must be sorted according to their color locations ("binning"). The closer the tolerances to the wavelength of the emitted primary radiation are set, the higher the quality of devices consisting of more than one semiconductor chip. But even after sorting with tight tolerances, the peak wavelength of the semiconductor chips may change significantly at variable operating temperatures and throughput currents. In general lighting and other applications, this may result in a change in optical properties, such as color location and color temperature. In addition, for conventional solutions in the range of 450 nm to 500 nm of the electromagnetic spectrum, there is a spectral gap in the emission spectrum in which no or only very little light is emitted. This results in a reduction of the color rendering index compared to the reference light source.

The phosphor (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.4 <r ≦ 1, for example NaLi ₃ SiO ₄ : Eu or (Na _0.5 K _{0, 5} ) Li ₃ SiO ₄ : Eu, can be efficiently excited with a primary radiation of 300 nm to 440 nm. The combination of a semiconductor chip with a primary radiation of 300 nm to 440 nm, for example based on GaInN, leads to the emission of a secondary radiation in the blue spectral range, which is stable over a much wider temperature range and larger ranges for the forward currents. Since the primary radiation of 300 nm to 440 nm is not or hardly visible, a wide variety of semiconductor chips can be used as a primary radiation source and still obtain a constant and stable emission spectrum of the conversion LED. Thus, a complex "binning" of the semiconductor chips can be avoided or simplified and the efficiency can be increased. A peak wavelength of the phosphor in the range of 450 nm and 500 nm increases the emission in this range. This can be increased with advantage the color rendering index.

In accordance with at least one embodiment, the illumination device, in particular the conversion light-emitting diode, is configured to emit blue radiation. The phosphor has the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.4 <r ≦ 1, preferably 0.45 <r ≦ 1, most preferably r = 0.5, on. Preferably, TA = Li, TD = Si and XB = O. For example, the luminous substance has the formula (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu. The peak wavelength of the phosphor is in the blue spectral range. It is possible that the conversion element consists of this phosphor or this phosphor and the matrix material. In particular, the conversion element or the lighting device, in particular the conversion LED according to this embodiment, no further phosphor, the phosphor can thus thus be present as the only phosphor in the conversion element or the lighting device, in particular the conversion LED. Advantageously, it is possible with the illumination device, in particular the conversion LED according to this embodiment, to achieve many color locations in the blue region of the electromagnetic spectrum, which can not be achieved so far.

The illumination devices, in particular the conversion LEDs of this embodiment, are suitable, for example, for signal lights, such as blue lights of, for example, police, medical, ambulance or fire fighting vehicles. Since these signal lights must be very bright on the one hand and on the other hand in a certain Farbortbereich (usually the dominant wavelength between 465 nm and 480 nm) must be, not all blue light sources are suitable for this use. On the other hand, lighting device, in particular conversion LEDs with the phosphor (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.4 <r ≦ 1, in particular with (Na _{0, 5} K _0.5 ) Li ₃ SiO ₄ : Eu, capable of suppressing melatonin production in humans. The lighting device, in particular conversion LED according to this embodiment can thus be used selectively to increase the alertness and / or the ability to concentrate. For example, it can help to overcome a jet lag faster. In addition, the phosphor or a lighting device, in particular a conversion LED with the phosphor for "color on demand" applications, that is for lighting devices, in particular conversion LEDs adapted to consumer needs blue color locations, for example, for the realization of certain brand-specific or product-specific colors For example, in advertising or in the interior design of cars.

In accordance with at least one embodiment, the illumination device, in particular the conversion LED, has a filter or filter particles which absorbs the primary radiation and / or partially the secondary radiation. In particular, the illumination device, in particular the conversion LED, has a filter or filter particles absorbing the primary radiation and / or partially the secondary radiation when the illumination device, in particular the conversion LED, is used for the backlighting of display elements.

In one embodiment, the filters are red, green and blue color filter systems.

In one embodiment, the color filter system each has a half width in the range of 70 to 120 nm for the colors red, green, blue.

The color filter system preferably comprises a blue filter, a green filter and a red filter, which filter the total radiation to light of first, second and third transmission spectrum.

In one embodiment, the emission of the illumination device, in particular the conversion LED and the transmission of the color filter system are chosen so that the maxima are at similar wavelengths. As a result, there is little reabsorption on the color filter system.

In one embodiment, the phosphor or phosphor is homogeneously distributed in the conversion element.

In one embodiment, the phosphor or phosphors are distributed with a concentration gradient in the conversion element.

In one embodiment, the phosphor having a shorter peak wavelength is located downstream of the phosphor or phosphors having a longer peak wavelength to reduce absorption losses.

In one embodiment, the phosphor or phosphors are particles of the corresponding phosphor.

The particles of the phosphors can independently of one another have an average particle size between 1 μm and 50 μm, preferably between 5 μm and 40 μm, particularly preferably between 8 μm and 35 μm, very particularly preferably between 8 μm and 30 μm. With these particle sizes, the primary radiation or the secondary radiation is scattered on these particles advantageously little and / or mainly in the forward direction, which reduces efficiency losses.

In one embodiment, the conversion element consists of the phosphor and the matrix material or the phosphors and the matrix material.

In one embodiment, the conversion element is formed as a small plate.

In one embodiment, the platelet has a thickness of 1 .mu.m to 1 mm, preferably 10 .mu.m to 150 .mu.m, particularly preferably 25 .mu.m to 100 .mu.m.

The layer thickness of the entire plate can be uniform. Thus, a constant color location can be achieved over the entire surface of the platelet.

In one embodiment, the conversion element may be a ceramic plate. By this is meant that the plate consists of co-sintered particles of the phosphor or the phosphors.

In one embodiment, the platelet comprises a matrix material, for example glass, in which the phosphor or phosphors is or are embedded. The plate may also consist of the matrix material, for example of glass, and the one or more phosphors. Also suitable as matrix materials for the platelet are silicones, epoxy resins, polysilazanes, polymethacrylates and polycarbonates, and combinations thereof.

According to one embodiment, the conversion element is designed as a small plate, which is arranged above the primary radiation source or the layer sequence.

The conversion element may be formed as platelets mounted directly on the primary radiation source or the layer sequence. It is possible that the plate completely covers the entire surface, in particular the radiation exit surface of the primary radiation source or of the layer sequence.

The lighting device, in particular the conversion LED, may comprise a housing. In the housing, a recess may be present in the middle. The primary radiation source or the layer sequence can be mounted in the recess. It is also possible that one or more further of the primary radiation sources or layer sequences are mounted in the recess.

It is possible for the recess to be filled with a potting covering the primary radiation source or the layer sequence. The recess may also consist of an airspace.

In one embodiment, the conversion element is arranged above the recess of the housing. In particular, in this embodiment there is no direct and / or positive contact of the conversion element with the primary radiation source or the layer sequence. This means that there can be a gap between the conversion element and the primary radiation source or layer sequence. In other words, the conversion element is arranged downstream of the primary radiation source or the layer sequence and is illuminated by the primary radiation. An encapsulation or an air gap can then be formed between the conversion element and the primary radiation source or the layer sequence. This arrangement can be referred to as "remote phosphor conversion".

In one embodiment, the conversion element is part of a potting of the primary radiation source or the layer sequence or the conversion element forms the potting.

In one embodiment, the conversion element is formed as a layer. The layer can be arranged over the radiation exit surface of the primary radiation source or of the layer stack or over the radiation exit surface and the side surfaces of the primary radiation source or of the layer stack.

It is the use of a lighting device, in particular a conversion LED specified. All features of the lighting device and the conversion LED are also disclosed for their use and vice versa.

It is the use of a lighting device, in particular a conversion LED for backlighting of display devices, in particular displays specified.

For example, they are displays of televisions such as liquid crystal televisions, computer monitors, tablets or smartphones.

For the backlighting of display elements, the illumination devices used, in particular conversion LEDs, firstly have to have high brightness and, secondly, to cover a large color space. Known filter systems used in conversion LEDs for backlighting consist of three or four color filters (blue, green and red or blue, green, yellow and red). The filters usually have a half-width in the range of typically 70 to 120 nm. The transmission results from the superposition of the three color filters, resulting in regions of the visible spectrum in which no complete transmission is achieved. As a result, with a broadband spectrum of the conversion LED that backlit the color filters, a portion of the emitted light is absorbed by the filter. To obtain the maximum amount of light from the conversion LED at the display level, therefore, narrow-band phosphors are needed. In addition, in order to obtain a high color saturation, it is important that the individual emissions of the conversion LEDs spectrally in each case respond as possible only one color of the color filter system.

Surprisingly, the illumination devices according to the invention, in particular conversion LEDs are very well suited for the backlighting of displays. In particular, a lighting device, in particular a conversion LED with a conversion element comprising the phosphor of the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.1 <r ≦ 0.4 preferably 0.15 <r ≦ 0.35, more preferably 0.2 <r ≦ 0.3, most preferably r = 0.25 or (Rb _{r '} Li _1-r' ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0 ≦ r '≦ 1, preferably 0.25 ≦ r' ≦ 0.75, particularly preferably 0.4 ≦ r '≦ 0.6, has proven particularly suitable for the backlighting of display elements Since the peak wavelength of the phosphor is in the green spectral range of the electromagnetic spectrum and has a half-width of less than 50 nm. Due to the low half-width of the phosphors according to the invention, the emission peaks show a very large overlap with the transmission range of a standard green filter, so that only little light is lost and the achievable color space is large.

The use of a lighting device, in particular a conversion LED in blue light sources, for reducing melatonin production or for color-on-demand applications is specified. The illumination device, in particular the conversion light-emitting diode, is configured to emit blue radiation. The phosphor preferably has the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.4 ≦ r ≦ 1, preferably 0.45 ≦ r ≦ 1, very particularly preferably r = 0.5, up. Preferably, TA = Li, TD = Si and XB = O. For example, the luminous substance has the formula (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu. The peak wavelength of the phosphor is in the blue spectral range.

By lowering melatonin production, alertness and / or concentration can be increased.

It is indicated the use of a lighting device, in particular a conversion LED for general lighting. The illumination device, in particular the conversion light-emitting diode, is configured to emit white radiation. In particular, it is warm white radiation with a color temperature below 3500 K, preferably below 3000 K.

For general lighting, the phosphor has, for example, the formula (Na _r K _{1 -r} ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0 ≦ r ≦ 0.1, preferably 0 ≦ r ≦ 0.15, particularly preferably r = 0, on. Preferably, TA = Li, TD = Si and XB = O. For example, the phosphor KLi ₃ SiO ₄ : Eu. The phosphor emits very broadband from the blue to red spectral range, so that a white-colored light impression is created. The illumination device, in particular the conversion LED according to this embodiment emits a warm-white radiation having a color temperature below 3500 K, in particular below 3000 K.

For general lighting, the phosphor may also have the following formula
(Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.4 <r ≦ 1, preferably 0.45 <r ≦ 1, most preferably r = 0.5 or 1, have. Preferably, TA = Li, TD = Si and XB = O. For example, the phosphor has the formula NaLi ₃ SiO ₄ : Eu or (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu. The peak wavelength of the phosphor is preferably in the blue spectral range, in particular in the range between 450 nm and 500 nm. The conversion element comprises a second and a third phosphor, wherein the second phosphor is adapted to the electromagnetic primary radiation in part to an electromagnetic secondary radiation in the red spectral range convert and the third phosphor is adapted to convert the electromagnetic primary radiation into an electromagnetic secondary radiation in the green spectral range during operation of the lighting device.

A display device is indicated. The display device comprises a lighting device, in particular a conversion LED. All features of the display device are also disclosed for the lighting device, in particular the conversion LED and its use, and vice versa.

In accordance with at least one embodiment, the display device is a display, for example a television, a smartphone, a computer screen or a tablet.

In accordance with at least one embodiment, the illumination device, in particular the conversion LED, has a conversion element comprising the phosphor of the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.1 <r ≦ 0.4, preferably 0.15 <r ≦ 0.35, more preferably 0.2 <r ≦ 0.3, most preferably r = 0.25 or (Rb _{r '} Li _1-r' ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E where 0 ≦ r '≦ 1, preferably 0.25 ≦ r' ≦ 0.75, more preferably 0.4 ≦ r '≦ 0.6, most preferably r' = 0.5, on. The conversion element comprises a second phosphor, which is set up during operation of the illumination device to partially convert the electromagnetic primary radiation into an electromagnetic secondary radiation which lies in the red spectral region of the electromagnetic spectrum.

embodiments

The first embodiment (AB1) of the phosphor according to the invention has the empirical formula NaLi ₃ SiO ₄ : Eu ²⁺ (2 mol% Eu ²⁺ based on the molar amount of Na) and is prepared as follows: Na ₂ CO ₃ , Li ₂ CO ₃ , SiO ₂ and Eu ₂ O ₃ are melted in a stoichiometric ratio corresponding to the molecular formula in an open nickel crucible. The initial weights of the reactants are shown in Table 1 below. The nickel crucible containing the mixed educts is heated for one hour to approximately 1000 ° C. under a forming gas atmosphere (N ₂ : H ₂ = 92.5: 7.5) and then cooled. Further heating under the same forming gas atmosphere and to temperatures below the melting point of the phosphor can be performed to further improve the optical properties of the phosphor. Table 1: reactant Amount of substance / mmol Mass / g Na ₂ CO ₃ 21.82 2313 Li ₂ CO ₃ 66.21 4892 SiO ₂ 43.94 2640 Eu ₂ O ₃ 12:44 0155

The educts of the phosphor are commercially available, stable and also very inexpensive. The simple synthesis at comparatively low temperatures makes the phosphor very inexpensive to manufacture and thus economically attractive.

The phosphor of the first embodiment (AB1) shows an emission in the blue spectral region of the electromagnetic spectrum.

The second embodiment (AB2) of the phosphor according to the invention has the empirical formula KLi ₃ SiO ₄ : Eu ²⁺ (2 mol% Eu ²⁺ based on the molar amount of K) and is prepared as follows: K ₂ CO ₃ , Li ₂ CO ₃ , SiO ₂ and Eu ₂ O ₃ are melted in a stoichiometric ratio corresponding to the molecular formula in an open nickel crucible. The initial weights of the reactants are shown in Table 2 below. The nickel crucible containing the mixed educts is heated for one hour at about 1000 ° C. under a forming gas atmosphere (N ₂ : H ₂ = 92.5: 7.5) and then cooled. Further heating under the same forming gas atmosphere and to temperatures below the melting point of the phosphor can be performed to further improve the optical properties of the phosphor. Table 2: reactant Amount of substance / mmol Mass / g K ₂ CO ₃ 40.78 5636 Li ₂ CO ₃ 123.71 9141 SiO ₂ 82,10 4933 Eu ₂ O ₃ 0.82 0290

The phosphor of the second embodiment (AB2) shows a broad emission from the blue to red spectral region of the electromagnetic spectrum and thus emits white, in particular warm white, radiation with a color temperature below 3500 K.

The third embodiment (AB3) of the phosphor according to the invention has the empirical formula (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu ²⁺ (2 mol% Eu ²⁺ based on the molar amount of Na and K) or NaKLi ₆ Si ₂ O ₈ : Eu ²⁺ and is prepared as follows: K ₂ CO ₃ , Na ₂ CO ₃ , Li ₂ CO ₃ , SiO ₂ and Eu ₂ O ₃ are melted in a stoichiometric ratio corresponding to the empirical formula in an open nickel crucible. The initial weights of the educts are given in Table 3 below. The nickel crucible containing the mixed educts is heated for one hour to eight hours at 800 ° C. to 1100 ° C. under a forming gas atmosphere (N ₂ : H ₂ = 92.5: 7.5). heated and then cooled. Further heating under the same forming gas atmosphere and to temperatures below the melting point of the phosphor can be performed to further improve the optical properties of the phosphor. Table 3: reactant Amount of substance / mmol Mass / g Na ₂ CO ₃ 10.65 1,129 K ₂ CO ₃ 10.44 1,443 Li ₂ CO ₃ 63.97 4,727 SiO ₂ 42.46 2,551 Eu ₂ O ₃ 0.43 0,150

The phosphor of the third embodiment (AB3) exhibits emission in the blue spectral region of the electromagnetic spectrum.

The fourth embodiment (AB4) of the phosphor according to the invention has the empirical formula (Na _0.25 K _0.75 ) Li ₃ SiO ₄ : Eu ²⁺ (2 mol% Eu ²⁺ based on the molar amount of Na and K) or NaK ₃ Li ₁₂ Si ₄ O ₁₆ : Eu ²⁺ and is prepared as follows: K ₂ CO ₃ , Na ₂ CO ₃ , Li ₂ CO ₃ , SiO ₂ and Eu ₂ O ₃ are in a stoichiometric ratio in an open nickel crucible in a molecular formula mixed. The initial weights of the reactants are shown in Table 4 below. The nickel crucible containing the mixed educts is heated at 900 ° C. to 1100 ° C. for four hours under a forming gas atmosphere (N ₂ : H ₂ = 92.5: 7.5) and then cooled. Further heating under the same forming gas atmosphere and to temperatures below the melting point of the phosphor can be performed to further improve the optical properties of the phosphor. Table 4: reactant Amount of substance / mmol Mass / g Na ₂ CO ₃ 5.24 0555 K ₂ CO ₃ 15:50 2142 Li ₂ CO ₃ 62.90 4648 SiO ₂ 41.75 2508 Eu ₂ O ₃ 12:42 0147

The phosphor of the fourth embodiment (AB4) exhibits emission in the green spectral region of the electromagnetic spectrum.

The fifth embodiment (AB5) of the phosphor according to the invention has the empirical formula (Rb _0.5 Li _0.5 ) Li ₃ SiO ₄ : Eu ²⁺ (2 mol% Eu ²⁺ based on the molar amount of (Rb _0.5 Li _{0, 5} )) or RbLiLi ₆ Si ₂ O ₈ : Eu ^2+, respectively, and is prepared as follows: Rb ₂ CO ₃ , Li ₂ CO ₃ , SiO ₂ and Eu ₂ O ₃ have a stoichiometric ratio in an open nickel crucible in a molecular formula mixed. The initial weights of the educts are shown in Table 5 below. The nickel crucible containing the mixed educts is heated for four hours to approximately 1000 ° C. under a forming gas atmosphere (N ₂ : H ₂ = 92.5: 7.5) and then cooled. The resulting product is then ground and a green powder is obtained.

Further heating under the same forming gas atmosphere and to temperatures below the melting point of the phosphor can be performed to further improve the optical properties of the phosphor. Table 5: reactant Amount of substance / mmol Mass / g Rb ₂ CO ₃ 5.17 3937 Li ₂ CO ₃ 52.30 3864 SiO ₂ 34.56 2076 Eu ₂ O ₃ 12:35 0122

The phosphor of the fifth embodiment (AB5) exhibits emission in the green spectral region of the electromagnetic spectrum.

Further advantageous embodiments and developments of the invention will become apparent from the embodiments described below in conjunction with the figures.

1A . 1B . 1C . 1D . 1E . 1F show a selection of possible, electroneutral sum formulas of substitution experiments.

2 . 13 . 23 . 38 . 63 show emission spectra of embodiments of the phosphor according to the invention.

3 . 14 . 24 . 39 . 64 show the Kubelka-Munk functions for embodiments of the phosphor according to the invention.

4 . 43 . 66 show a comparison of optical properties of an embodiment of the phosphor according to the invention with comparative examples.

5 . 6 . 44 . 67 show a comparison of emission spectra of an embodiment with comparative examples.

7 shows a comparison of the Kubelka-Munk function of an embodiment with comparative examples.

8th . 18 . 25 show sections of the crystal structure for embodiments of the phosphor according to the invention.

9 . 19 . 40 . 65 show X-ray powder diffraction patterns using copper K _α1 radiation.

10 . 20 . 26 show Rietveld refinements of X-ray powder diffractograms of embodiments of the phosphor according to the invention.

11 . 12 . 21 . 22 . 27 . 28 show characteristic properties of embodiments of the phosphor according to the invention.

15 . 16 show comparisons of emission spectra of a conversion LED with an embodiment of the phosphor according to the invention with comparative examples.

17 shows a comparison of optical properties of a conversion LED with an embodiment of the phosphor according to the invention with comparative examples.

29 shows a comparison of emission spectra of an embodiment with comparative examples and the sensitivity curve for melatonin production.

30 shows the overlap of emission spectra of different phosphors and different blue emitting LEDs with the sensitivity curve for melatonin production.

31 shows color loci of different phosphors in the CIE Normtafel (1931).

32 . 33 . 34 show comparisons of color purity at different dominant wavelengths of the primary radiation of an embodiment with comparative examples.

35 . 36 . 37 show simulated LED spectra at different excitation wavelengths.

41 shows the reflex positions and the relative intensity of the reflections of the X-ray powder diffraction pattern of an embodiment of the phosphor according to the invention.

42 shows the thermal quenching behavior of an embodiment of the phosphor according to the invention compared to a conventional phosphor.

45 shows the coverage of the color space rec2020 by different combinations of green and red phosphor.

46 to 53 show graphical representations of the coverage of the color space rec2020 by different combinations of green and red phosphor.

54A . 54B and 54C show the coverage of different standard color spaces and color loci of filtered spectra of different combinations of green and red phosphor.

55 to 58 show the spanned color spaces of different combinations of green and red phosphor in an excitation with a primary radiation λdom = 448 nm.

59 to 62 show the emission spectra of conversion LEDs with different combinations of green and red phosphor.

68 to 70 show schematic side views of various embodiments of conversion LEDs described here.

1A . 1B . 1C . 1D . 1E and 1F show tables with possible, electroneutral phosphors, which are replaced by substitution experiments, analogous to the general empirical formula (MA) _a (MB) _b (MC) _c (MD) _d (TA) _e (TB) _f (TC) _g (TD) _h (TE ) _i (TF) _j (XA) _k (XB) ₁ (XC) _m (XD) _n . The substitutions shown are exemplary only, other substitutions are also possible. The activator E is shown only in the general formula and not in the specific embodiments, but still present in the specific embodiments.

In 2 is the emission spectrum of the first embodiment AB1 of the phosphor according to the invention with the empirical formula NaLi ₃ SiO ₄ shown. The wavelength is plotted in nanometers on the x-axis and the emission intensity in percent on the y-axis. For measuring the emission spectrum, the phosphor according to the invention was excited with primary radiation having a wavelength of 400 nm. The phosphor has a half width of 32 nm or 1477 cm ^-1 and a dominant wavelength of 473 nm, the peak wavelength is about 469 nm.

3 shows a normalized Kubelka-Munk function (K / S) plotted against the wavelength λ in nm for the first embodiment (AB1) of the phosphor according to the invention. K / S was calculated as follows:

K / S = (1-R _inf ) ² / 2R _inf ), where R _inf corresponds to the diffuse reflection (remission) of the phosphor.

Out 3 It can be seen that the maximum of K / S for the first embodiment (AB1) of the phosphor according to the invention is about 360 nm. High K / S values mean high absorption in this area. The phosphor can be excited efficiently with a primary radiation from about 300 nm to 430 nm or 440 nm.

In 4 is a comparison of the half-width (FWHM), the peak wavelength (λ _peak ), the dominant wavelength (λ _dom ) and the light output (LER) between a first comparative example (VB1: BaMgAl ₁₀ O ₁₇ : Eu), a second comparative example (VB2: Sr ₅ (PO ₄ ) ₃ Cl: Eu), a third comparative example (VB3: BaMgAl ₁₀ O ₁₇ : Eu) and the first exemplary embodiment of the phosphor according to the invention NaLi ₃ SiO ₄ : Eu (AB1). VB1 and VB3 differ in the concentration of Eu. All phosphors emit radiation in the blue region of the electromagnetic spectrum. The peak wavelength of the phosphor according to the invention NaLi ₃ SiO ₄ : Eu is somewhat longer wavelength compared to the comparative examples. As can be seen, the phosphor according to the invention NaLi ₃ SiO ₄ : Eu has a significantly lower half-width and / or a higher light output (LER) than the comparative examples. The shift of the peak wavelength to a longer wavelength and the smaller half width result in an increase in the overlap with the eye sensitivity curve. Thus, the phosphor according to the invention has a very high and compared to the comparative examples higher luminescence efficiency or luminous efficacy.

The 5 and 6 show the emission spectra of VB1, VB2, VB3 and AB1 as shown in 4 are described. In 5 the wavelength in nanometers is plotted on the x-axis and the emission intensity in percent on the y-axis. In 6 the wave number in cm ^{-1 is} plotted on the x-axis and the emission intensity in percent on the y-axis. Here, the significantly lower half-width of the phosphor according to the invention NaLi ₃ SiO ₄ : Eu in comparison to VB1 and VB3 (BaMgAl ₁₀ O ₁₇ : Eu) can be seen. BaMgAl ₁₀ O ₁₇ : In contrast to AB1, Eu phosphors show a low absorption from a wavelength of 350 nm (cf. 7 ). Together with the relatively large half-width, this leads to a relatively poor color purity of the phosphors VB1 and VB3. Although the known phosphor VB2 shows a small half-width, it has the disadvantage that it contains chlorine. Many applications are subject to strict conditions regarding the chlorine content, so that the use of this phosphor is already limited. Another disadvantage is the risk of release of corrosive HCl during its production, which increases the costs of the synthesis equipment and their maintenance measures.

7 shows a normalized Kubelka-Munk function (K / S) plotted against the wavelength λ in nm for different phosphors VG1, VG2, VG3 and AB1 as shown in FIG 4 are defined. The curve with the reference symbols VG1, VG2 and VG3 represents K / S for known phosphors, the curve with the reference symbol AB1 represents K / S for the first embodiment of the phosphor according to the invention. It can be seen that the phosphor AB1 according to the invention has a higher absorption in comparison to the comparative examples VG1, VG2 and VG3 at relatively long wavelengths, in particular in the range from 360 nm. This is particularly advantageous since efficient excitation of the phosphor according to the invention with a primary radiation of a peak wavelength in the UV range to blue range of the electromagnetic spectrum, in particular in the range between 300 nm to 460 nm, preferably between 300 nm to 430 nm or 440 nm, is possible , Therefore, the phosphor according to the invention is particularly well in combination with semiconductor chips having a primary radiation in the range between 300 nm to 430 nm or 440 nm, applicable.

8th shows the tetragonal crystal structure of the phosphor NaLi ₃ SiO ₄ : Eu in a schematic representation. The hatched circles represent the Na atoms. The crystal structure corresponds to the crystal structure of NaLi ₃ SiO ₄ , as in B. Nowitzki, R. Hoppe, News on Type A [(TO) n] oxides: NaLi3SiO4, NaLi3GeO4, NaLi3TiO4, Revue de Chimie minérale, 1986, 23, 217-230 is described. The crystal structure is that of CaLiAl ₃ N ₄ : Eu, described in P. Pust, AS Wochnik, E. Baumann, PJ Schmidt, D. Wiechert, C. Scheu, W. Schnick, Ca [LiAl3N4]: Eu2 + - A Narrow-Band Red-Emitting Nitridolithoaluminates, Chemistry of Materials 2014 26, 3544- 3549 isotype.

In 9 For example, two X-ray diffraction powder diffractograms are given using copper K _α1 radiation. The diffraction angles are given in ° 2θ values on the x-axis and the intensity on the y-axis. The X-ray powder diffraction pattern provided with the reference I shows that of the first embodiment AB1 of the phosphor according to the invention NaLi ₃ SiO ₄ : Eu. The X-ray powder diffraction pattern provided with the reference symbol II shows that from the crystal structure of NaLi ₃ SiO ₄ ( B. Nowitzki, R. Hoppe, News on Type A [(TO) n] oxides: NaLi3SiO4, NaLi3GeO4, NaLi3TiO4, Revue de Chimie minérale, 1986, 23, 217-230 ) simulated X-ray powder diffraction pattern for NaLi ₃ SiO ₄ . From the agreement of the reflections, it can be seen that the phosphor according to the invention NaLi ₃ SiO ₄ : Eu crystallizes in the same crystal structure as NaLi ₃ SiO _4.

In 10 there is a crystallographic evaluation. 10 shows a Rietveld refinement of the X-ray powder diffractogram of the first embodiment AB1, ie for NaLi ₃ SiO ₄ : Eu. For the Rietveld refinement, the atomic parameters for NaLi ₃ SiO ₄ (Table 7 in B. Nowitzki, R. Hoppe, Revue de Chimie Minérale, 1986, 23, 217-230 ) was used to show that the crystal structure of NaLi ₃ SiO ₄ : Eu is that of NaLi ₃ SiO ₄ corresponds. In the upper diagram, the superposition of the measured reflections with the calculated reflections for NaLi ₃ SiO _{4 is} shown. The lower diagram shows the differences between the measured and calculated reflections.

11 shows crystallographic data of NaLi ₃ SiO _4.

12 shows atomic layers in the structure of NaLi ₃ SiO _4.

In 13 the emission spectrum of the second embodiment AB2 of the phosphor according to the invention is represented by the empirical formula KLi ₃ SiO ₄ : Eu ²⁺ . The wavelength is plotted in nanometers on the x-axis and the emission intensity in percent on the y-axis. For measuring the emission spectrum, the phosphor according to the invention was excited with primary radiation having a wavelength of 400 nm. The phosphor shows a broadband emission of about 430 nm to about 780 nm and thus emits white radiation or generates the emitted radiation a white light impression. Advantageously, the color locus of the phosphor is close to that of Planck's radiator at 2700 K. The color locus is at the following coordinates CIE-x = 0.449 and CIE-y = 0.397 in the CIE standard color chart from 1931. The color temperature (CCT) is 2742 K, the luminous efficacy or luminescence efficiency at 290 lm / W, the CRI (color rendering index) is 81 and the color rendering index R9 at 21. Thus, a conversion LED comprising the novel luminophore KLi ₃ SiO ₄ : Eu ^{2+ is} particularly suitable for general lighting ,

14 shows a normalized Kubelka-Munk function (K / S), plotted against the wavelength λ in nm, for the second embodiment (AB2) of the phosphor according to the invention. Out 14 It can be seen that the maximum of K / S for the second embodiment (AB2) of the phosphor according to the invention is about 340 nm. The phosphor can be excited efficiently with a primary radiation from about 300 nm to 430 nm or 440 nm.

15 and 16 show simulated emission spectra of different conversion LEDs that emit white radiation. The primary radiation source used is an InGaN-based semiconductor layer sequence which has a primary radiation with a peak wavelength of 410 nm (FIG. 15 ) or with a peak wavelength of 390 nm ( 16 ) emitted. The structure of the conversion LEDs is in 17 shown. As can be seen, the conversion LEDs (LED 1 and LED 2 ) using only one phosphor, the inventive KLi ₃ SiO ₄ : Eu ²⁺ , similar emission spectra as the comparative examples VLED2 and VLED1 each having a green and a red phosphor. Advantageously, it is thus possible with the phosphor according to the invention to provide a conversion LED, the warm white light with a color temperature below 3500 K, preferably below 3000 K, emitted and only a phosphor required and not known as white-emitting conversion LEDs, the need at least a green and a red phosphor in combination with a blue primary radiation.

In 17 different properties of conversion LEDs with the phosphor according to the invention KLi ₃ SiO ₄ : Eu ²⁺ (LED1, LED2) and the comparative examples (VLED1 and VLED2) are compared. λ _prim stands for the wavelength of the primary radiation. In the third and fourth column, the first and second phosphors are indicated. CIE-x and CIE-y indicate the color coordinates x and y of the radiation in the 1931 CIE standard color chart. CCT / K indicates the correlated color temperature of the total radiation in Kelvin. R9 stands for a color rendering index known to those skilled in the art (saturated red). LER stands for the luminous efficacy in lumens per watt. As can be seen, the conversion LEDs with the phosphor according to the invention KLi ₃ SiO ₄ : Eu ²⁺ as a single phosphor have similar optical properties as conventional conversion LEDs, based on two phosphors. But there are the disadvantages away, resulting in the use of two or more phosphors. First, the resulting spectrum depends strongly on the ratio of the phosphors used. As a result of batch fluctuations in phosphor production, frequent adjustments of the concentration of the phosphors are necessary, which makes the production of the conversion LEDs very expensive. The phosphors also show different emission properties depending on the temperature, the radiation density of the primary radiation and the excitation wavelength and also have a different Degradierverhalten, ie a different stability in terms of temperature, radiation, moisture or gas influences on. Also, the production of phosphor mixtures can be difficult if the phosphors differ greatly in their physical properties such as density, grain size and sedimentation behavior. All these effects lead to fluctuating color distributions and color shifts in the products when using two phosphors. Conventionally, to achieve a high color rendering index, advantageously with a low color temperature, in particular below 3500 K or below 3000 K, red-emitting phosphors are required. However, all known red emitting phosphors can only by means of expensive Manufacturing methods are synthesized and are therefore much more expensive than known green and yellow phosphors. The phosphor according to the invention KLi ₃ SiO ₄ : Eu ²⁺ , however, can be produced inexpensively, since the starting materials are commercially available, stable and also very inexpensive. In addition, the synthesis does not require an inert gas atmosphere and is therefore comparatively simple.

The use of the phosphor of the invention in a white-emitting conversion LED has numerous advantages. It can be used a primary radiation that is not or barely perceived by the human eye (300 nm to 430 nm or 440 nm). Variations in the primary radiation do not have a negative effect on the overall radiation properties. No color matching is necessary since the emission spectrum is constant. The conversion LEDs can be manufactured with high throughput, since no color matching or complex chip binning is necessary. There are no color shifts or other negative effects on the emission spectrum due to selective degradation of only one phosphor or changes in primary radiation caused by temperature or forward current variations. Furthermore, the conversion LED has no intrinsic color, but shows a white appearance when switched off. Therefore, the phosphor is also suitable for "remote phosphor" arrangements in which no yellow or orange appearance in the off state is desired. Depending on the application, partial conversion of the primary radiation can also take place. Since it is possible to excite the phosphor with a primary radiation in the range of 300 nm to 430 nm or 440 nm, a contribution of the primary radiation, preferably in the short-wave blue region of the electromagnetic spectrum, to the total radiation results in objects illuminated thereby becoming whiter, more radiant and therefore more attractive. Thus, for example, optical brighteners in textiles can be stimulated.

18 shows the triclinic crystal structure of the phosphor KLi ₃ SiO ₄ : Eu in a schematic representation. The hatched circles represent the K atoms. The crystal structure corresponds to the crystal structure of KLi ₃ SiO ₄ , as in K. Werthmann, R. Hoppe, On Oxides of the New Formula Type A [(T4O4)]: For information on KLi3GeO4, KLi3SiO4 and KLi3TiO4, Z. Anorg. Gen. Chem., 1984, 509, 7-22 is described. The crystal structure is that of SrLiAl ₃ N ₄ : Eu, described in P. Pust, V. Weiler, C. Hecht, A. Tücks, AS Wochnik, A.-K. Henß, D. Wiechert, C. Scheu, PJ Schmidt, W. Schnick, Narrow-Band Red-Emitting Sr [LiAl3N4]: Eu2 + as a Next-Generation LED Phosphor Material Nat. Mater. 2014 13, 891-896 isotype.

In 19 For example, two X-ray diffraction powder diffractograms are given using copper K _α1 radiation. The diffraction angles are given in ° 2θ values on the x-axis and the intensity on the y-axis. The X-ray powder diffraction pattern provided with the reference numeral III shows that of the second embodiment of the phosphor of the invention KLi ₃ SiO ₄ : Eu. The provided with the reference numeral IV Röntgenbeugungspulverdiffraktogramm shows the crystal structure of KLi ₃ SiO ₄ simulated Röntgenbeugungspulverdiffraktogramm for KLi ₃ SiO. ₄ From the agreement of the reflections, it can be seen that the phosphor according to the invention KLi ₃ SiO ₄ : Eu crystallizes in the same crystal structure as KLi ₃ SiO _4.

In 20 there is a crystallographic evaluation. 20 shows a Rietveld refinement of the X-ray powder diffractogram of the second embodiment AB2, ie KLi ₃ SiO ₄ : Eu. For the Rietveld refinement, the atomic parameters for KLi ₃ SiO ₄ ( K. Werthmann, R. Hoppe, On Oxides of the New Formula Type A [(T4O4)]: For information on KLi3GeO4, KLi3SiO4 and KLi3TiO4, Z. Anorg. Gen. Chem., 1984, 509, 7-22 ) to show that the crystal structure of KLi ₃ corresponds to SiO ₄ : Eu that of KLi ₃ SiO ₄ . In the upper diagram, the superposition of the measured reflections with the calculated reflections for KLi ₃ SiO _{4 is} shown. The lower diagram shows the differences between the measured and calculated reflections. A peak of an unknown minor phase was marked with asterisks.

21 shows crystallographic data of KLi ₃ SiO _4.

22 shows atomic layers in the structure of KLi ₃ SiO _4.

In 23 the emission spectrum of the third embodiment AB3 of the phosphor according to the invention with the molecular formula (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu ^{2+ is} shown. The wavelength is plotted in nanometers on the x-axis and the emission intensity in percent on the y-axis. For measuring the emission spectrum, the phosphor according to the invention was excited with primary radiation having a wavelength of 400 nm. The phosphor has a half width of less than 20 nm and a peak wavelength of 486 nm. With this low half-width, this phosphor is one of the narrowest known Eu ²⁺ -doped phosphors. The peak wavelength lies in the blue-green, also cyan-markable, spectral range of the electromagnetic spectrum. So far, only a few phosphors with a peak wavelength in this area are known and none of these phosphors has such a small half-width. With a Peak wavelength of 486 nm and the small half width, the phosphor has a good overlap with the eye sensitivity curve. The conversion of the UV or blue primary radiation into a secondary radiation with a slightly longer wavelength in the blue region of the electromagnetic spectrum (peak wavelength of 486 nm) increases the efficiency of the conversion LED. The peak wavelength of the secondary radiation is closer to the maximum of the eye sensitivity at 555 nm compared to the primary radiation, whereby the emitted radiation has a higher overlap with the eye sensitivity curve and is therefore perceived as lighter.

24 shows a normalized Kubelka-Munk function (K / S) plotted against the wavelength λ in nm for the third embodiment (AB3) of the phosphor according to the invention. Out 24 It can be seen that the maximum of K / S for the third embodiment (AB3) of the phosphor according to the invention is between 350 nm and 420 nm. Up to 500 nm, K / S is well above zero. The phosphor (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu ²⁺ can be efficiently excited with a primary radiation from about 340 nm.

25 shows the tetragonal crystal structure of the phosphor (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu ²⁺ in a schematic representation. The hatched circles represent the Na atoms, the white circles fill the K atoms. The crystal structure was determined from X-ray powder diffraction data. As a starting point, the crystal structure of CsKNa ₂ Li ₁₂ Si ₄ O _{16 was used} with exchange of Cs for K.

In 26 there is a crystallographic evaluation. 26 shows a Rietveld refinement of the X-ray powder diffractogram of the third embodiment AB3, ie (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu ²⁺ . The parameters and atomic coordinates of all non-Li atoms were freely refined. In the upper diagram, the superposition of the measured reflections with the calculated reflections for CsKNa ₂ Li ₁₂ Si ₄ O _{16 is} shown. The lower diagram shows the differences between the measured and calculated reflections. The phosphor (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu ²⁺ is structurally isotypic to the compounds CsKNa ₂ Li ₈ {Li [SiO ₄ ]} ₄ , RbNa ₃ Li ₈ {Li [SiO ₄ ]} ₄ , CsNa ₃ Li ₈ {Li [GeO ₄ ]} ₄ and RbNa ₃ Li ₈ {Li [TiO ₄ ]} ₄ . The structure is also similar to that of the first embodiment NaLi ₃ SiO ₄ : Eu and the second embodiment KLi ₃ SiO ₄ : Eu of the phosphor according to the invention, but has a complicated arrangement of the alkali metals

27 shows crystallographic data of (Na _0.5 K _0.5 ) Li ₃ SiO _4.

28 shows atomic layers in the structure of (Na _0.5 K _0.5 ) Li ₃ SiO _4.

The 29 shows the emission spectra of the third embodiment of the inventive phosphor AB3 and three comparative examples ClS, OS and G, where ClS for Ca ₈ Mg (SiO ₄ ) ₄ Cl ₂ : Eu, OS for (Sr, Ba) ₂ SiO ₄ : Eu and G for Lu ₃ (Al, Ga) ₅ O ₁₂ : Ce stands. All phosphors emit in the blue to blue-green region of the electromagnetic spectrum. As can be seen, AB3 has the lowest half-width and the peak wavelength is shifted to shorter wavelengths compared to the comparative examples. Thus, the phosphor according to the invention is suitable for example for use in signal lights such as blue lights of, for example, police, medical, ambulance or fire-fighting vehicles whose dominance wavelength is preferably in a range between 465 nm and 480 nm. The use of the comparative examples is less suitable for this because their peak wavelengths are more than 510 nm, whereas the phosphor according to the invention has a peak wavelength of 486 nm.

The curve labeled smel shows the sensitivity curve for melatonin production, that is, at which wavelengths the melatonin production in the body can best be suppressed ("human response function for melanopic effects"; Lucas et al., Trends in Neurosciences January 2014 Vol. 1 ). As can be seen, the emission spectrum of AB3 shows a high overlap with smel so that this radiation can be effectively used to suppress melatonin formation. Thus, irradiation with this radiation can lead to increased alertness or concentration.

30 shows the overlap of emission spectra of different phosphors (AB3, CIS, OS and G, as described in 29 described) and various blue emitting LEDs (unconverted) with the sensitivity curve for melatonin production. The LEDs are light emitting diodes with InGaN based semiconductor chips. The LEDs Ipeak430nm (peak wavelength 430 nm) and Ipeak435nm (peak wavelength 435 nm) are not usually commercially available in large numbers but are very efficient. The LEDs Ipeak440nm (peak wavelength 440 nm), Ipeak445nm (peak wavelength 445 nm), Ipeak450nm (peak wavelength 450 nm) and Ipeak455nm (peak wavelength 455 nm) are commercially available, inexpensive and efficient. The LEDs Ipeak460nm (peak wavelength 460 nm), Ipeak465nm (peak wavelength 465 nm) and Ipeak470nm (peak wavelength 470 nm) are not very efficient and are not commercially viable usually available. InGaN-based semiconductor chips can in principle emit radiation with a peak wavelength of up to 500 nm, but the efficiency decreases as the wavelength increases, which is why these are usually only produced in large numbers up to a peak wavelength of up to about 460 nm. As a result, the applications of InGaN-based semiconductor chips in light-emitting diodes (without phosphor) are limited. As can be seen, the emission of the inventive phosphor AB3 shows a greater overlap with the sensitivity curve for melatonin production than the phosphors ClS, OS and G and also as the InGaN-based LEDs. Thus, melatonin production can be efficiently suppressed with the phosphor of the present invention.

In 31 the CIE standard table (1931) is shown, wherein the CIE-x component of the primary color red and the y-axis the CIE-y component of the primary color green are plotted on the x-axis. In the CIE standard panel are the color locations of different phosphors (AB3, ClS, OS and G, as under 29 described). The black squares represent chromaticity coordinates of various blue and blue-green InGaN semiconductor chips with peak wavelengths between 430 nm and 492 nm and dominance wavelengths between 436 nm and 493 nm.

The black dot marks the white point Ew with the coordinates CIE-x = 1/3 and CIE-y = 1/3. The black lines, which connect the color dots of a blue indium gallium nitride semiconductor chip (λpeak = 445 nm, λdom = 449 nm) to the color loci of the phosphors, represent the conversion lines of conversion LEDs made up of the indium gallium nitride semiconductor chip and the corresponding phosphors , The area labeled EVL shows the typical blue color space for products for use in the area of signal lights for, for example, police vehicles. The open circles mark color loci with 100% chroma for selected dominant wavelengths at 468 nm, 476 nm, and 487 nm. The dashed line represents color loci at 487 nm with different color purity. Color loci on this dashed line that are closer to the open circle 487 show higher color purity than color loci closer to the white point E. From this figure, the advantageous effects of the new phosphor AB3 become clear: The conversion line (K) of a typical blue LED to the color location of the phosphor AB3 according to the invention intersects the EVL color space in the middle, whereas the conversion lines of the same blue LED with the phosphors OS, ClS and G show only a slight overlap with the EVL color space. This can advantageously be achieved by using the phosphor AB3 more color spaces within the EVL color space than with the conventional phosphors. In addition, the conversion line K intersects the dotted line for the dominant wavelength 487 nm in the point I1, which has higher color purity compared to the intersections of the conversion lines of the known phosphors. The same color purity improvement using the phosphor AB3 of the present invention also shows for other target dominant wavelengths, especially within the EVL color space. The corresponding lines are not shown for clarity. High color purity leads to a more saturated color impression. With the phosphor according to the invention it is thus possible to achieve additional color locations, which can not be achieved so far. The phosphor according to the invention (Na _0.5 K _0.5 ) Li ₃ SiO ₄ : Eu ²⁺ is therefore particularly suitable for conversion LEDs which emit blue radiation with high color saturation. These conversion LEDs are suitable for use in blue lights or for "color-on-demand" applications.

The 32 . 33 and 34 show a comparison of the achievable color purity of different conversion LEDs at different target dominant wavelengths and wavelengths of the primary radiation. To carry out the simulation experiments, a blue semiconductor chip with the different phosphors AB3, ClS, OS and G was combined. In this case, semiconductor chips based on InGaN were used, which have a high efficiency. The content of phosphor was varied for each experiment to achieve the target dominant wavelength, then the color purity was determined from the resulting spectra. The results show that for all chosen target dominant wavelengths and all selected wavelengths of the primary radiation, the conversion LEDs with the phosphor AB3 exhibit a significantly higher color purity than the comparative examples.

The 35 . 36 and 37 show the ones to the 32 . 33 and 34 corresponding simulated emission spectra of the conversion LEDs. It shows 35 the emission spectra of a conversion LED with a primary radiation of 430 nm and a conversion LED with a primary radiation of 455 nm each with the phosphor AB3 at a target dominant wavelength of 487 nm. 36 shows the emission spectra of a conversion LED with a primary radiation of 430 nm and a conversion LED with a primary radiation of 455 nm each with the phosphor AB3 at a target dominant wavelength of 468 nm. 37 shows the emission spectra of a conversion LED with a primary radiation of 430 nm and a conversion LED with a primary radiation of 455 nm each with the phosphor AB3 at a target dominant wavelength of 476 nm.

In 38 is the emission spectrum of the fourth embodiment AB4 of the phosphor according to the invention with the empirical formula (Na _0.25 K _0.75 ) Li ₃ SiO ₄ : Eu ²⁺ shown. The wavelength is plotted in nm on the x-axis and the emission intensity in% on the y-axis. To measure the emission spectrum of the phosphor according to the invention was excited with a primary radiation of a wavelength of 400 nm. The phosphor has a half width of less than 50 nm, a peak wavelength of 529 nm, a dominant wavelength of 541 nm, and a color spot in the CIE color space having the coordinates CIE-x: 0.255 and CIE-y: 0.680. The narrow half-width of the phosphor results in a saturated green emission of the phosphor.

39 shows a normalized Kubelka-Munk function (K / S) plotted against the wavelength λ in nm for the fourth embodiment (AB4) of the phosphor according to the invention. With a primary radiation in the range between 330 nm and 500 nm, preferably 340 nm to 460 nm, particularly preferably 350 nm to 450 nm, the phosphor according to the invention can be efficiently excited. As a result, the phosphor is particularly suitable for backlighting applications, using a semiconductor chip with a primary radiation in the near UV region or blue region of the electromagnetic spectrum.

In 40 the X-ray powder diffractogram of the fourth embodiment AB4 is shown. The intensity is shown on the y-axis and the ° 2θ values on the x-axis. In 41 the reflex positions and the relative intensity in% of the reflex positions of the X-ray powder diffractogram are indicated.

In 42 the emission intensity in% is plotted against the temperature in ° C. As can be seen, the embodiment AB4 of the phosphor according to the invention shows a high thermal stability. In 42 is the thermal quenching behavior of the phosphor AB4 according to the invention compared to a conventional phosphor OS2, a green orthosilicate of the formula (Sr, Ba) ₂ SiO ₄ : Eu shown. The phosphors were excited with a blue primary radiation having a wavelength of 460 nm at various temperatures of 25 to 225 ° C and their emission intensity was recorded. It can be clearly seen that the inventive phosphor AB4 has a significantly lower loss of emission intensity at typical temperatures prevailing in a conversion LED, in particular temperatures above 140 ° C. Advantageously, the phosphor can thus be used at higher operating temperatures in conversion LEDs.

The 43 shows various optical properties of the fourth embodiment of the phosphor according to the invention AB4 compared to conventional phosphors G2 and OS2. OS2 stands for a phosphor of the formula (Sr, Ba) ₂ SiO ₄ : Eu and G ₂ for a phosphor of the formula Lu ₃ (Al, Ga) ₅ O ₁₂ : Ce. All three phosphors show a similar dominant wavelength. However, the inventive phosphor AB4 shows a significantly higher light output (LER) and a significantly higher color purity. This results in improved color saturation, allowing for greater color space coverage, and improved overall efficiency. The reason for the improved properties is the low half-width of the fourth embodiment AB4 with the formula (Na _0.25 K _0.75 ) Li ₃ SiO ₄ : Eu ^{2+ of} the phosphor according to the invention in comparison to the conventional phosphors. The high luminous efficacy increases the efficiency of green conversion LEDs with partial or full conversion compared to green conversion LEDs with known green phosphors having a comparable dominance and / or peak wavelength.

44 shows a comparison of the emission spectra of the fourth embodiment AB4 of the phosphor according to the invention in comparison to the under 43 described conventional phosphors G2 and OS2.

In 45 For example, the coverage of the color space rec2020 (xy) in the CIE color space system and rec2020 (u'v ') in the CIE LUV color space system (1976) is shown by different combinations of a green phosphor and a red phosphor in conjunction with blue primary radiation of different dominant wavelengths , AB4 stands for the fourth embodiment (Na _0.25 K _0.75 ) Li ₃ SiO ₄ : Eu ^{2+ of} the phosphor according to the invention and AB5 for the fifth embodiment (Rb _0.5 Li _0.5 ) Li ₃ SiO _{4 of} the invention Leuchtstoffs, BS stands for a conventional green emitting beta SiAlON: Eu phosphor. The proportions of blue, green and red radiation were adjusted to achieve the white color location for typical backlighting applications (CIE-x = 0.278 and CIE-y = 0.255). Typical color filter curves were applied to the resulting spectrum and the resulting color points for blue, green and red were calculated. The overlap of the resulting color space with the standard color spaces was then calculated and compared. In all cases, it can be seen that the spectra obtained with the embodiments AB4 and AB5 of the phosphor according to the invention lead to a greater coverage of the respective color space. With the phosphors according to the invention can thus be reproduced a wider range of colors. Thus, for example, a display device, such as a display, with a conversion LED comprising the phosphor according to the invention, reproduce a significantly increased number of colors than has hitherto been possible with conventional phosphors.

The 46 to 53 show a graphical representation of the in 45 The results describe the color space coverage for a dominant wavelength of the primary radiation at 448 nm. In the diagrams, the second red phosphor used in each case is indicated by its empirical formula.

The 54A . 54B and 54C show a more comprehensive list of data 45 which additionally show the color locations of the filtered spectra and covers with other standard color spaces.

The 55 to 58 show the spanned color spaces of different examples of in 45 Each figure shows a comparison of three different green phosphors (AB4, AB5 or BS) each combined with a red phosphor indicated by its molecular formula in the figures. The spanned color spaces with the inventive embodiments AB4 and AB5 are almost congruent. It can be seen that with embodiments AB4 and AB5 of the phosphor according to the invention, a greater range of colors can be reproduced, especially in the green and red corner of the spanned color triangle (marked with arrows). This is attributed to the very narrow-band emission of the inventive phosphors AB4 and AB5. The range of green colors is thus increased by the use of the inventive phosphors AB4 and AB5 compared to conventional phosphors. The narrow half-width of the phosphors according to the invention also reduces the radiation loss resulting from the filtering. In comparison with the known phosphor β-SiAlON (BS), the phosphors according to the invention can be prepared starting from inexpensive educts and, moreover, the synthesis takes place at moderate temperatures. This keeps manufacturing costs low, which also makes the phosphors economically very attractive for the production of mass products, such as LCD TVs, computer monitors or displays for smartphones or tablets.

The 59 to 62 show the corresponding conversion LED spectra of the examples of 55 to 58 , The red phosphor is indicated by its molecular formula in the figures.

In 63 the emission spectrum of the fifth embodiment AB5 of the phosphor according to the invention with the empirical formula (Rb _0.5 Li _0.5 ) Li ₃ SiO _{4 is} shown. The wavelength is plotted in nm on the x-axis and the emission intensity in% on the y-axis. For measuring the emission spectrum, the phosphor according to the invention was excited with light having a wavelength of 400 nm. The phosphor has a half-width of 43 nm and a peak wavelength of 528 nm and a dominant wavelength of 539 nm. The coordinates CIE-x and CIE-y are 0.238 and 0.694. Thus, the phosphor proves to be very suitable for backlighting applications, which must have a saturated green tone.

64 shows a normalized Kubelka-Munk function (K / S) plotted against the wavelength λ in nm for the fifth embodiment of the phosphor according to the invention. The maximum of K / S for the fifth embodiment of the phosphor according to the invention is about 400 nm, but the high absorption range extends into the blue-green spectral range up to about 500 nm. Therefore, the phosphor can efficiently with a primary radiation having a wavelength between 330 and 500 nm, preferably 340 and 460 nm, particularly preferably 350 to 450 nm, are excited.

65 shows the X-ray powder diffractogram of the fifth embodiment AB5 of the phosphor according to the invention with the reference symbol V. The X-ray powder diffractogram provided with the reference VI shows a simulated of the compound RbLi (Li ₃ SiO ₄ ) ₂ ( K. Bernet, R. Hoppe, A "Lithosilicate" with Columnar Units: RbLi5 {Li [SiO4] 2, Z. Anorg. Gen. Chem., 1991, 592, 93-105 ). Peaks in the X-ray powder diffraction pattern V which can be assigned to the secondary phase Li ₄ SiO ₄ are marked with asterisks.

The 66 shows various optical properties of the fifth embodiment of the phosphor according to the invention AB5 compared to conventional phosphors G1 and OS1. OS1 stands for a phosphor of the formula (Sr, Ba) ₂ SiO ₄ : Eu and G1 for a phosphor of the formula Lu ₃ (Al, Ga) ₅ O ₁₂ : Ce. In comparison with the phosphors G2 and OS2, the phosphors G1 and OS1 have a different Eu or Ce content, respectively, in order to achieve the same dominance wavelength as the exemplary embodiment AB5. All three phosphors show a similar dominant wavelength. However, the inventive phosphor AB5 shows a significantly higher light output (LER) and a significantly higher color purity. This results in improved color saturation, allowing greater color space coverage, and improved overall efficiency. The reason for the improved properties is the low half-width of the fourth embodiment AB5 of the formula (Rb _0.5 Li _0.5 ) Li ₃ SiO _{4 of} the phosphor according to the invention in comparison to the conventional phosphors. The high luminous efficacy increases the efficiency of partial or full conversion green conversion LEDs compared to green conversion LEDs with known green phosphors of comparable peak wavelength.

67 shows a comparison of the emission spectra of the fifth embodiment AB5 of the phosphor according to the invention compared to the under 66 described conventional phosphors G1 and OS1.

The conversion LED according to 68 has a layer sequence 2 on that on a substrate 10 is arranged. The substrate 10 may be formed, for example, reflective. Over the layer sequence 2 is a conversion element 3 arranged in the form of a layer. The layer sequence 2 has an active layer (not shown) that emits a primary radiation having a wavelength of 300 to 500 nm in the operation of the conversion LED. The conversion element is arranged in the beam path of the primary radiation S. The conversion element 3 comprises a matrix material, such as a silicone and particles of the phosphor (Rb _0.5 Li _0.5 ) Li ₃ SiO ₄ : Eu with an average particle size of 10 microns, the primary radiation during operation of the conversion LED at least partially into secondary radiation converted in the green region of the electromagnetic spectrum. The phosphor is in the conversion element 3 homogeneously distributed in the matrix material within the manufacturing tolerance. The conversion element 3 is above the radiation exit surface 2a the sequence of layers 2 and over the side surfaces of the layer sequence 2 Applied over the entire surface and communicates with the radiation exit surface 2a the sequence of layers 2 and the side surfaces of the layer sequence 2 in direct mechanical contact. The primary radiation can also over the side surfaces of the layer sequence 2 escape.

The conversion element 3 For example, it can be applied by injection molding, transfer molding or spray coating. In addition, the conversion LED has electrical contacts (not shown) whose design and arrangement is known to the person skilled in the art.

In 69 is another embodiment of a conversion LED 1 shown. Compared to 68 is the conversion element 3 shaped as platelets. The platelet can consist of sintered particles of the phosphor and thus be a ceramic platelet, or the platelet comprises, for example, glass, silicone, an epoxy resin, a polysilazane, a polymethacrylate or a polycarbonate as matrix material with particles of the phosphor embedded therein. The conversion element 3 is above the radiation exit surface 2a the sequence of layers 2 applied over the entire surface. In particular, no primary radiation passes over the side surfaces of the layer sequence 2 out, but mainly on the radiation exit surface 2a , The conversion element 3 can on the layer sequence via an adhesive layer (not shown), for example made of silicone 2 be upset.

The conversion LED 1 according to 70 has a housing 11 with a recess. In the recess is a layer sequence 2 disposed having an active layer (not shown) which emits a primary radiation having a wavelength of 300 to 460 nm in the operation of the conversion LED. The conversion element 3 is as casting the layer sequence 2 formed in the recess and comprises a matrix material, such as a silicone and a phosphor, such as KLi ₃ SiO ₄ : Eu, the primary radiation during operation of the conversion LED 1 at least partially converted into a secondary radiation, which gives a white-colored luminous impression. It is also possible that the phosphor in the conversion element 3 spatially above the radiation exit surface 2a is concentrated. This can be achieved, for example, by sedimentation.

The invention is not limited by the description based on the embodiments of these. Rather, the invention encompasses any novel feature as well as any combination of features, including in particular any combination of features in the claims, even if this feature or combination itself is not explicitly stated in the patent claims or exemplary embodiments.

This patent application claims the priority of German patent application 10 2016 114 996.9 , the disclosure of which is hereby incorporated by reference.

LIST OF REFERENCE NUMBERS

ppm

 parts per million

λpeak

 Peak wavelength

λdom

 Dominant wavelength

AB1

 first embodiment

STARTING AT 2

 second embodiment

FROM 3

 third embodiment

FROM 4

 fourth embodiment

FROM 5

 Fifth embodiment

G

 gram

e

 emission

mmol

 millimoles

mol%

 mole percent

R _inf

 diffuse reflection

lm

 lumen

W

 watt

LER

 light output

LED

 light emitting diode

CRI

 Color rendering index

CCT

 correlated color temperature

R9

 Color rendering index

K / S

 Kubelka-Munk function

K

 Kelvin

cm

 centimeter

nm

 nanometer

° 2θ

 Grade 2 Theta

I, II, III, IV, V, VI

 X-ray powder

Ew

 White point

K

 conversion line

T

 temperature

° C

 centigrade

1

 Conversion LED

2

 Layer sequence / semiconductor chip

2a

 Radiation exit area

3

 conversion element

10

 substratum

11

 casing

S

 Beam path of the primary radiation

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2013/175336 A1 [0037, 0037]
• WO 2015/052238 A1 [0127]
• DE 102016114996 [0277]

Cited non-patent literature

• EU Directive 2011/65 / EU [0007]
• B. Nowitzki, R. Hoppe, News about type A [(TO) n] oxides: NaLi3SiO4, NaLi3GeO4, NaLi3TiO4, Revue de Chimie minérale, 1986, 23, 217-230 [0228]
• P. Pust, AS Wochnik, E. Baumann, PJ Schmidt, D. Wiechert, C. Scheu, W. Schnick, Ca [LiAl3N4]: Eu2 + - A Narrow-Band Red-Emitting Nitridolithoaluminates, Chemistry of Materials 2014 26, 3544- 3549 [0228]
• B. Nowitzki, R. Hoppe, News on Type A [(TO) n] Oxides: NaLi3SiO4, NaLi3GeO4, NaLi3TiO4, Revue de Chimie minérale, 1986, 23, 217-230 [0229]
• B. Nowitzki, R. Hoppe, Revue de Chimie Minérale, 1986, 23, 217-230 [0230]
• K. Werthmann, R. Hoppe, On Oxides of the New Formula Type A [(T4O4)]: For information on KLi3GeO4, KLi3SiO4 and KLi3TiO4, Z. Anorg. Gen. Chem., 1984, 509, 7-22 [0238]
• P. Pust, V. Weiler, C. Hecht, A. Tücks, AS Wochnik, A.-K. Henß, D. Wiechert, C. Scheu, PJ Schmidt, W. Schnick, Narrow-Band Red-Emitting Sr [LiAl3N4]: Eu2 + as a Next-Generation LED Phosphor Material Nat. Mater. 2014 13, 891-896 [0238]
• K. Werthmann, R. Hoppe, On Oxides of the New Formula Type A [(T4O4)]: For information on KLi3GeO4, KLi3SiO4 and KLi3TiO4, Z. Anorg. Gen. Chem., 1984, 509, 7-22 [0240]
• Lucas et al., Trends in Neurosciences January 2014 Vol. 1 [0250]
• K. Bernet, R. Hoppe, A "Lithosilicate" with Columnar Units: RbLi5 {Li [SiO4] 2, Z. Anorg. Gen. Chem., 1991, 592, 93-105 [0269]

Claims (16)

Lighting device comprising a phosphor having the general empirical formula (MA) _a (MB) _b (MC) _c (MD) _d (TA) _e (TB) _f (TC) _g (TD) _h (TE) _i (TF) _j (XA ) _k (XB) ₁ (XC) _m (XD) _n , wherein - MA is selected from a group of monovalent metals comprising Li, Na, K, Rb, Cs, Cu, Ag and combinations thereof, - MB from a Is selected from the group consisting of divalent metals comprising Mg, Ca, Sr, Ba, Zn, Mn, Eu, Yb, Ni, Fe, Co and combinations thereof, - MC is selected from a group of trivalent metals containing Y, Fe, Comprising Cr, Sc, In, rare earth metals and combinations thereof, - MD is selected from a group of tetravalent metals comprising Zr, Hf, Mn, Ce and combinations thereof, - TA is selected from a group of monovalent metals, Li, Na, Cu, Ag, and combinations thereof, - TB is selected from a group of divalent metals, Mg, Zn, Mn, Eu, Yb, Ni, and combinations thereof, - TC from a group of tr is selected from the group consisting of B, Al, Ga, In, Y, Fe, Cr, Sc, rare earth metals and combinations thereof, - TD is selected from a group of tetravalent metals comprising Si, Ge, Sn, Mn, Ti, Zr, Hf, Ce and combinations thereof, - TE is selected from a group of pentavalent elements comprising P, Ta, Nb, V and combinations thereof, - TF is selected from a group of hexavalent elements which include W, Mo and Combinations thereof, - XA is selected from a group of elements comprising F, Cl, Br and combinations thereof, - XB is selected from a group of elements comprising O, S and combinations thereof, - XC = N - XD = C - a + b + c + d = t - e + f + g + h + i + j = u - k + l + m + n = v - a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j - k - 2l - 3m - 4n = w - 0.8 ≤ t ≤ 1 - 3.5 ≤ u ≤ 4 - 3.5 ≤ v ≤ 4 - (-0.2) ≤ w ≤ 0.2 and 0 ≤ m <0.875 v and / or v ≥ l> 0.12 5 v. Chr. Lighting device according to claim 1, wherein the lighting device is a conversion light emitting diode ( 1 ), comprising - a primary radiation source ( 2 ), which is set up to emit an electromagnetic primary radiation during operation of the diode, - a conversion element ( 3 ) comprising the phosphor which is arranged in the beam path of the electromagnetic primary radiation, wherein the phosphor is adapted to at least partially convert the electromagnetic primary radiation into an electromagnetic secondary radiation during operation of the illumination device. Lighting device according to one of the preceding claims, wherein the following applies to the phosphor: - a + b + c + d = 1 - e + f + g + h + i + j = 4 - k + l + m + n = 4 - a + 2b + 3c + 4d + e + 2f + 3g + 4h + 5i + 6j - k - 2l - 3m - 4n = 0 and - m <3.5. Lighting device according to one of the preceding claims 2 or 3, wherein the primary radiation source ( 2 ) is adapted to emit during operation of the diode, an electromagnetic primary radiation having a wavelength between 300 nm inclusive and including 500 nm. Lighting device according to one of the preceding claims, wherein the phosphor has one of the following general empirical formulas: (MA) Li _3-x Si _1-x Zn _x Al _x O ₄ : E (MA) Li _3-x Si _1-x Mg _x Al _x O ₄ : E (MA) _1- x'Ca _{x '} Li ₃ Si _{1-x '} Al _x' O ₄ : E (MA) _{1-x "} Ca _x" Li _{3-x "} Si _1-x" Mg _{2x "} O ₄ : E (MA) Li _{3 2z} Mg _3z Si _1-z O ₄ : E or (MA) Li ₃ Si _{1-2z '} Al _z' P _{z '} O ₄ : E, where 0 ≤ x ≤ 1, 0 ≤ x' ≤ 1, 0 ≤ x '' ≦ 1, 0 ≦ z ≦ 1, 0 ≦ z '≦ 0.5 and E is selected from a group comprising Eu, Ce, Yb, Mn and combinations thereof. Lighting device according to one of the preceding claims, wherein the phosphor has one of the following general _empirical formulas: (MA) _1-y Ca _y Li _3-2y Al _3y Si _1-y O _4-4y N _4y : E (MA) Li _{3-y '} Al _y' SiO _{4-2y '} N _2y' : E (MA) Li _{3-y ''} Mg _{y ''} SiO _{4-y ''} N _{y ''} : E (MA) _{1-w '''} Ca _{w '''} Li ₃ SiO _4-w''' N _{w '''} : E (MA) Li _3-w' Al _{2w '} Si _1-w' O _{4-w '} N _w' : E or (MA) _{1 -w "} Ca _w" Li _{3-w "} Si _1-w" Al _{2w "} O _4-2w" N _{2w "} : E, where 0 ≤ y ≤ 0.875, 0 ≤ y '≤ 1 , 75, 0 ≦ y '' ≦ 3, 0 ≦ w '''≦ 1, 0 ≦ w' ≦ 1, 0 ≦ w '' ≦ 1, and E is selected from a group including Eu, Ce, Yb, Mn and combinations thereof. A lighting device according to any one of the preceding claims, wherein the phosphor has the following general molecular formula: (MA) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E, where MA is selected from a group of monovalent metals containing Li, Na , K, Rb and combinations thereof, - TA = Li - TD = Si and - XB = O and E is selected from a group comprising Eu, Ce, Yb, Mn and combinations thereof. Lighting device according to one of the preceding claims, wherein the phosphor has the general formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E or (Rb _{r '} Li _1-r' ) ₁ (TA ) ₃ (TD) ₁ (XB) ₄ : E, wherein 0 ≦ r ≦ 1, 0 ≦ r '≦ 1 and E is selected from a group comprising Eu, Ce, Yb, Mn, and combinations thereof. A lighting device according to claim 8, adapted to emit white radiation, said phosphor having the formula (Na _r K _{1 -r} ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E where 0 ≤ r ≤ 0 , 1. A lighting device according to claim 8, adapted to emit white radiation, said phosphor having the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.1 <r ≦ 1 or (Rb _{r '} Li _1-r' ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0 ≦ r '≦ 1, and wherein the conversion element comprises at least one second phosphor arranged therefor in the operation of the lighting device, to partially convert the electromagnetic primary radiation into an electromagnetic secondary radiation located in the red spectral region of the electromagnetic spectrum. A lighting device according to claim 10, wherein the phosphor has the formula (Na _r K _{1 -r} ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.4 <r ≦ 1, and wherein the conversion element comprises a third phosphor adapted to operate the lighting device to partially convert the electromagnetic primary radiation into an electromagnetic secondary radiation located in the green spectral region of the electromagnetic spectrum. Lighting device according to claim 10, suitable for backlighting applications, wherein the phosphor has the formula (Na _r K _{1 -r} ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.1 <r ≤ 0.4 or (Rb _{r '} Li _1-r' ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0 ≤ r '≤ 1. Lighting device according to claim 12, wherein in addition a primary radiation and / or partially the secondary radiation absorbing filter or filter particles are present. A lighting device according to claim 8 adapted to emit blue radiation, said phosphor having the formula (Na _r K _1-r ) ₁ (TA) ₃ (TD) ₁ (XB) ₄ : E with 0.4 <r ≤ 1.  Use of a lighting device according to one of Claims 1 to 13 for backlighting display devices, in particular displays. Display device comprising a lighting device according to one of claims 1 to 13.

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