The object of the invention is a luminescence detector for temperature measurement, wherein a detection element is made of doped material. The object of the invention is also a method of temperature measuring of the objects using a luminescence detector according to the invention. Luminescent thermometers based on organic matrices co-doped with Tb ³⁺ and Eu ³⁺ ions are presented in the publications [1-6]. The disadvantage of these solutions is the low temperature stability of the used matrix.

Publications [7-20] presents the possibility of changes in the relative intensities of Er ³⁺ ion bands for non-contact temperature measurement. Whereas publication [21] discloses the use of Nd ³⁺ ions for non-contact temperature measurement. A significant disadvantage of these solutions is the low sensitivity of this type of thermometer , less than 1.6%/°C.

Further publications [22-24] disclose the use of changes in the relative intensity of Nd ³⁺ ion bands (bands Rl and R2) for temperature measurement. A significant disadvantage in this type of solution is the low sensitivity of temperature measurement, below 0.2%/°C.

Similar solutions disclosed in the publications [25, 26] are based on the use of changes in the relative intensities of Nd ³⁺ and Yb ³⁺ ion bands (bands 880 nm and 1030 nm and 1030 nm and 1060 nm) for temperature measurement. A significant disadvantage of this solution is the low sensitivity of this type of luminescence thermometers, less than 0.5%/°C.

The prior art discloses also a solution based on the use of changes in the relative intensities of emission components of Nd ³⁺ Starck's band.

Luminescent thermometers currently used are based on the use of the relative changes in emission bands associated with electronic transitions of f-f type of lanthanide ions. As shown above, a significant disadvantage of these solutions is the low sensitivity of this type of luminescent thermometers. Therefore, there is a need to solve the problem of low sensitivity of luminescent thermometers.

The aim of the present invention is improvement of the sensitivity of a luminescent thermometer.

Surprisingly, the inventors of the solution have developed a luminescent detector for temperature measurement, wherein a detection element is made of doped material comprising two types of ions.

The object of the invention is a luminescence detector for temperature measurement, wherein a detection element is made of doped material, characterized in that the material of the detection element is a phosphor doped with transition metal ions and lanthanide ions, wherein the sensitivity of the temperature measurement is above 2%/°C.

Preferably, in the luminescence detector according to the invention, the phosphor is doped with transition metal ions selected from a group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Ru, Rh, Cd, Ta, W, Re, Os, Ir, and lanthanide ions selected from a group consisting of Nd ³⁺ , Er ^3"1" , Yb ³⁺ .

Preferably, in the luminescence detector according to the invention, the phosphor is selected from a group of oxide or fluoride matrix doped with ions of Cr ³⁺ , Nd ³⁺ , Yb ³⁺ , Er ³⁺ , Mn ²⁺ .

Preferably, in the luminescence detector according to the invention, the phosphor is selected from a group of matrix consisting of LiLaP ₄ 0i ₂ doped with ions of l%Cr ³⁺ and 5%Nd ³⁺ or LiLaP ₄ 0i ₂ doped with ions of 2%Cr ³⁺ and 10%Yb ³⁺ or Y2O3 doped with ions of 0.5%Cr ³⁺ and 5%Έ^ ⁺ or NaGdF ₄ doped with ions of 0.5%Cr ³⁺ and l%Nd ³⁺ or NaYF ₄ doped with ions of 0.5%Mn ²⁺ and l%Nd ³⁺ or NaLaF ₄ doped with ions of 0.5% Mn ²⁺ and 1% Yb ³⁺ .

In the optical luminescence temperature detector according to the invention, which based on the analysis of changes in the emission spectra as a function of temperature the changes in relative intensities of f-d type luminescence bands of transition metal ions and f-f type bands of lanthanide ions were used. In contrast to f-f type bands, the f-d type luminescence bands are strongly dependent on temperature and their emission intensity is severely reduced with increasing temperature. Therefore, in the solution according to the invention by using the change in the ratio of luminescence spectrum of f-d bands and f-f bands the non-contact temperature measurement with a high measurement sensitivity above 2%/°C is possible.

Because of their physicochemical properties the transition metal ions are prone to so-called "temperature luminescence quenching" that is, an increase of the temperature results in a strong decrease in the intensity of their emissions. On the other hand, the emission intensity of the lanthanide ions is slightly dependent on temperature. Therefore, considering the intensity of the emission band of lanthanides as a reference band the non-contact temperature measurement with high sensitivity of the measurement can be performed.

Sensitivity of the luminescence thermometer is understood as: S=(1/M)*(AM/AT)* 100%

S -luminescence thermometer sensitivity

M- band intensity ratio

ΔΜ- the change of band intensity in the temperature change ΔΤ

Due to using the change in the relative intensities of bands of transition metal ions and lanthanide ions the sensitivity of luminescent thermometer increased above 2%/°C.

The object of the invention is also a method of non-contact temperature measurement of various types of objects, characterized in that the material of a detection element of a luminescent detector, which is a phosphor doped with transition metal ions and lanthanide ions, with the sensitivity of the temperature measurement above 2%/°C is excited by electromagnetic radiation beam with the wavelength range of 250-800 nm, and then the change of relative intensities of luminescent bands generated by the phosphor in temperature function is measured. Preferably, in the method of non-contact temperature measurement of the objects according to the invention electromagnetic radiation beam is a laser beam with a wavelength range 400-750 nm.

In the method of non-contact temperature measurement of various types of objects according to the invention, phosphor co-doped with transition metal ions and lanthanide ions is excited by electromagnetic radiation beam which allows for excitation of both transition metal ions and lanthanide ions. In the next step phosphor emission spectrum measurement is performed and relative intensity of band emission of a transition metal ion and lanthanide ion is analysed. Their ratio is designated as M. Changing the value of M parameter is associated with the temperature. Comparing the value of M parameter with its value for calibration measurement it is possible to read the temperature. So far, solutions known in the literature based on applying the ratio of the bands of one or more lanthanides to temperature measurement. Using the combination of emission of transition metal ions and lanthanide ions it is possible to increase the sensitivity, and thus a temperature measurement. Therefore, the solution according to the invention allows to increase the accuracy of temperature measurement compared to other luminescent thermometers.

The following table shows the sensitivity of different types of luminescent thermometers known in the prior art based on organic matrix co-doped with lanthanide ions.

Matrix Sensitivity Ref.

[%/°C]

LaMgAlnOi9 Er,Yb 0.27 [13]

NaYF ₄ Er,Yb 1.20 [7]

YV0 ₄ Er,Yb 1.17 [27]

Y2T12O7 Er,Yb 0.67 [28]

LiNbOs Er,Yb 1.40 [29]

AI2O3 Er,Yb 0.51 [30]

CaMo0 ₄ Er,Yb 1.43 [16]

SrW0 ₄ Er,Yb 1.49 [31]

CaW0 ₄ Er,Yb 0.92 [11] Matrix Sensitivity Ref.

[%/°C]

YNb0 ₄ Er,Yb 0.73 [32]

BaTi0 ₃ Er,Yb 0.45 [17]

Yb ₃ Al ₅ 0i ₂ Er,Yb 0.48 [8]

La ₂ 0 ₃ Er,Yb 0.91 [19]

(Na,Ba)Ti0 Er,Yb 0.31 [12]

NaYF ₄ Er,Yb 1.27 [9]

Y ₂ 0 Er,Yb 1.30 [33]

NaGdF ₄ Er,Yb 1.30 [34]

Te0 ₂ -PbF ₂ -AlF 1.24 [20]

(Gd,Yb,Er) ₂ 0 1.22 [10]

NaLnTi0 ₄ Er,Yb 1.20 [15]

GdV0 ₄ Er,Yb 1.20 [14]

NaYF ₄ Er,Yb 1.16 [35]

NaY(Mo0 ₄ ) ₂ Er,Yb 1.14 [36]

BaMo0 ₄ Er,Yb 1.09 [37]

Te0 ₂ -W0 Er,Yb 1.05 [31]

Y ₂ SiOs Er,Yb 1.08 [38]

ZnO-CaTi0 Er,Yb 0.91 [39]

Gd ₂ 0 Er,Yb 0.9 [40]

Fluorphosphate glass 0.829 [41]

LiLaP ₄ 0i ₂ Nd,Yb 0.3 [25]

LaF3 Nd Yb 0.41 [42]

Y3A15012Nd 0.13 [23]

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The description of the disclosed exemplary embodiments is provided. The invention is not intended to be limited to the exemplary embodiments shown herein and various modifications to these exemplary embodiments are possible without departing from the spirit or scope of the invention.

Example 1

A detection element of a luminescent detector is phosphor LiLaP ₄ 0i ₂ doped with ions of l%Cr ³⁺ and 5%Nd ³⁺ .

Temperature measurement on the outer surface of the high temperature furnace, inducing phosphor by a laser radiation beam with a wavelength range 665 nm. Phosphor emission spectrum measurement along with the band 800 intensity change analysis and band 1060 nm derived from ion Cr ³⁺ and ion Nd ³⁺ . Temperature measurement sensitivity was obtained at the level of 5 %/°C.

Example 2

A detection element of a luminescent detector is phosphor LiLaP ₄ 0i ₂ doped with ions of 2%Cr ³⁺ and 10%Yb ³⁺ .

Temperature measurement of HeLa tumor cells, inducing phosphor by a laser radiation beam with a wavelength range 500 nm. Phosphor emission spectrum measurement along with the band 800 intensity change analysis and band 1030 nm derived from ion Cr and ion Yb was measured. Temperature measurement sensitivity was obtained at the level of 3.5 %/°C.

Example 3

A detection element of a luminescent detector is phosphor Y2O3 doped with ions of 0.5%Cr ³⁺ and 5%Nd ³⁺ .

Temperature measurement of the rotating propeller was performed, inducing phosphor by a laser radiation beam with a wavelength range 500 nm. Phosphor emission spectrum measurement along with the band 680 intensity change analysis and band 1550 nm derived from ion Cr ³⁺ and ion Yb ³⁺ was measured. Temperature measurement sensitivity was obtained at the level of 4.5 %/°C.

Example 4

A detection element of a luminescent detector is phosphor NaGdF ₄ doped with ions of 0.5%Cr ³⁺ and l%Nd ³ .

Temperature measurement of the computer processor was performed, inducing phosphor by a laser radiation beam with a wavelength range 420 nm. Phosphor emission spectrum measurement along with the band 680 intensity change analysis and band 1064 nm derived from ion Cr ³⁺ and ion Nd ³⁺ . Temperature measurement sensitivity was obtained at the level of 6.5 %/°C.

Example 5

A detection element of a luminescent detector is phosphor NaYF ₄ doped with ions of 0.5%Mn ²⁺ and l%Nd ³⁺ .

Temperature measurement of the heating plate, inducing phosphor by a laser radiation beam with a wavelength range 400 nm. Phosphor emission spectrum measurement along with the band 600 intensity change analysis and band 870 nm derived from ion Mn ²⁺ and ion Nd ³⁺ . Temperature measurement sensitivity was obtained at the level of 3.5 %/°C. Example 6

A detection element of a luminescent temperature detector was phosphor doped with ions of 0.5%Mn ²⁺ and 1% Yb ³⁺ .

Temperature measurement of the electric heater was performed, inducing phosphor by a laser radiation beam with a wavelength range 550 nm. Phosphor emission spectrum measurement along with the band 600 intensity change analysis and band 1030 nm derived from ion Mn ²⁺ and ion Yb ³⁺ . Temperature measurement sensitivity was obtained at the level of 5.5 %/°C.