CN101430278A - Apparatus for measuring luminous efficiency of photoluminescent body - Google Patents

Abstract

The invention discloses a device for measuring the luminous efficiency of a photoinduced luminant. The device comprises an integrating sphere with an optical fiber input end and an optical fiber output end, a fiber laser which is connected with the input end of the integrating sphere and a calibration standard lamp. The integrating sphere is internally fixed with a sample platform and a baffle which is used for preventing the fluorescence emitted by luminous material from directly emerging at the output end of the integrating sphere. The output end of the integrating sphere is connected with the input end of a spectrophotometer. The output end of the spectrophotometer is connected with a computer. The device has simple structure and uses the integrating sphere to measure luminous flux, thereby reducing the influence of external environment on the measurement result, and the device has reliable and exact measurement result and good stability. The device is fit for measuring internal quantum efficiency and external quantum efficiency of fluid, solid and powder luminous material and has good universality.

Description

A kind of device of measuring luminous efficiency of photoluminescent body

Technical field

The present invention relates to measure the device of luminous efficiency of photoluminescent body, belong to field of optical measuring technologies.

Background technology

Along with the progress and the development of society, the theoretical constantly maturation of research embedded photoluminescent material, technology is constantly perfect, and performance improves constantly, and embedded photoluminescent material has been brought into play vital role in every field such as communication, illumination, demonstrations.In the communications field: optical fiber communication has so far developed into the System of all Optical Communication in the 5th generation.One of the Primary Component of all optical communication image intensifer, that the most frequently used is rare earth doped fiber amplifier (Erbium-Doped Fiber Amplifier (EDFA) EDFA), its chief component is the optical fiber of rare earth doped luminescent material, and optical fiber properties, parameter will directly influence the height of communication quality.In illumination and demonstration field: showing and throwing light on is two most important applications fields of luminescent material, and luminescent material also plays an important role in these two fields always.In recent years, new variation tendency has all appearred in demonstration and lighting field.The demonstration field, multiple flat panel display develops rapidly; Lighting field, the semiconductor lighting technology is a dark horse.With the fluorescent light of rare-earth trichromatic fluorescent powder manufacturing not only on luminescence efficiency more traditional general lighting light source great raising is arranged, and overcome the shortcoming that the traditional electrical light source can not be unified on luminescence efficiency and colour rendering.In September, 2008 electron trade standard " semiconductor light-emitting-diode fluorescent powder " is first with the height of external quantum efficiency replacement relative brightness in the past as the luminescence efficiency of estimating fluorescent powder.Fluorescence quantum yield claims fluorescence quantum efficiency again, is meant in the excited state molecule that the molecule of getting back to ground state by emitting fluorescence accounts for the mark of whole excited state molecules.Quantum yield depends on radiation and nonradiative transition process, promptly fluorescent emission, intersystem crossing, shift and the relative speed of interior transfer etc. outward.Since energy crisis took place the world in 1973, various countries were devoted to develop energy-saving luminescent material one after another.Therefore to the measurement of the fluorescence quantum efficiency of luminescent material and the only way which must be passed that evaluation also becomes the luminescent material of the novel function admirable of development.

Fluorescence quantum efficiency method of testing of Cun Zaiing and instrument mainly are at electroluminescent organic material OLED, chemiluminescent material in the market.For the measuring method and the device domestic research that this aspect is not arranged as yet at present of photoluminescence efficiency, the problem of utilizing integrating sphere method test light electroluminescent material fluorescence quantum efficiency mainly to exist has: how (1) gets rid of the influence that the measurement mechanism relative spectral sensitivity produces measurement result; (2) how to make measurement mechanism that different samples are comprised that liquid, solid, powder sample have versatility; (3) algorithm of luminescent material internal quantum efficiency and external quantum efficiency.

Summary of the invention

The purpose of this invention is to provide a kind of device of measuring luminous efficiency of photoluminescent body, with the fluorescence internal quantum efficiency of realizing bulk, liquid, powder embedded photoluminescent material and the measurement of external quantum efficiency.

The device of measurement luminous efficiency of photoluminescent body of the present invention, the integrating sphere that comprises band optic fibre input end and output terminal, fiber laser that is connected with the integrating sphere input end and calibration standard lamp, the integrating sphere internal fixation has sample stage and being used to block the shelves that fluorescence that luminescent material sends directly do not penetrate from the integrating sphere output terminal not pull, the output terminal of integrating sphere links to each other with the spectrophotometer input end, and spectrophotometric output terminal links to each other with computer.

In order to reduce the influence of baffle plate, can on pulling, shelves apply the coating identical with the integrating sphere inwall to measurement result.

During use, select different sampling receptacles at different samples, solid sample selects bulk sample anchor clamps, pulverized specimen to select sample cell, and liquid sample is selected sample cell, and sampling receptacle is fixed on the sample stage.

At first, relative spectral sensitivity S (λ) with standard lamp calibration measurement mechanism of the present invention: not setting-out of the sampling receptacle product of integrating sphere at this moment, close fiber laser, light standard lamp, the light that standard lamp sends is input to spectrophotometer through integrating sphere, by the spectral power distribution I (λ) of computer outputting standard lamp, the theoretical spectral distribute power of standard lamp is P (λ) after the spectrophotometer beam split, the then relative spectral sensitivity S of proving installation of the present invention (λ) (1) calculating by formula:

S(λ)＝I(λ)/P(λ) (1)

Then, open fiber laser, close standard lamp, sampling receptacle is not setting-out product still, and the light that fiber laser sends is input to the spectrophotometer beam split through integrating sphere, by computer output excitation spectrum La (λ); Then put into sample in sampling receptacle, the light direct irradiation that fiber laser sends is on sample, and the fluorescence spectrum of generation and remaining exciting light spectrum are exported remaining excitation spectrum Lb (λ) and fluorescence spectrum Y (λ) through the spectrophotometer beam split by computer.

Calculate total photon number A that exciting light sends by formula (2),

$A=\∫\frac{\mathrm{La}\left(\mathrm{\λ}\right)}{s\left(\mathrm{\λ}\right)}\frac{\mathrm{\λ}}{\mathrm{hc}}\mathrm{d\λ}---\left(2\right)$

In the formula, h is a Planck's constant, and c is the light velocity, and limit of integration is by the excitation wavelength decision of sample.

Calculate the photon number B that luminescent material absorbs by formula (3),

$B=\∫\frac{\mathrm{La}\left(\mathrm{\λ}\right)-\mathrm{Lb}\left(\mathrm{\λ}\right)}{s\left(\mathrm{\λ}\right)}\frac{\mathrm{\λ}}{\mathrm{hc}}\mathrm{d\λ}---\left(3\right)$

In the formula, h is a Planck's constant, and c is the light velocity, and limit of integration is by the excitation wavelength decision of sample.

Count C by the fluorescent photon that formula (4) calculating luminescent material sends,

$C=\∫\frac{Y\left(\mathrm{\λ}\right)}{s\left(\mathrm{\λ}\right)}\frac{\mathrm{\λ}}{\mathrm{hc}}\mathrm{d\λ}---\left(4\right)$

In the formula, h is a Planck's constant, and c is the light velocity, and limit of integration is by the fluorescence spectrum wavelength decision of the required sample of reality.

By the fluorescence internal quantum efficiency of formula (5) calculating luminescent material,

By the fluorescence external quantum efficiency of formula (6) calculating luminescent material,

Apparatus of the present invention are simple in structure, adopt integrating sphere to carry out luminous flux measurement, reduced the influence of external environment to measurement result, and measurement result is reliable, accurate.Apparatus of the present invention are applicable to the measurement of liquid, solid, powder luminous material internal quantum efficiency and external quantum efficiency, and versatility is good.

Description of drawings

Fig. 1 is a device synoptic diagram of measuring luminous efficiency of photoluminescent body.

Fig. 2 is the another kind of device synoptic diagram of measuring luminous efficiency of photoluminescent body.

Embodiment

Further specify the present invention below in conjunction with accompanying drawing.

Referring to Fig. 1, the device of measurement luminous efficiency of photoluminescent body provided by the invention, the integrating sphere 3 that comprises band optic fibre input end and output terminal, the fiber laser 1 and the calibration standard lamp 2 that are connected with integrating sphere 3 input ends, integrating sphere 3 internal fixation have sample stage 5 and are used to block the shelves that fluorescence that luminescent material sends directly do not penetrate from the integrating sphere output terminal does not pull 9, the output terminal of integrating sphere 3 links to each other with spectrophotometer 10 input ends, and the output terminal of spectrophotometer 10 links to each other with computer 11.

Excessive in laser optical power, and in the sampling receptacle during not setting-out product, laser beam with direct irradiation on the integration spherical shell, too high laser power density and energy density can cause integrating sphere to damage, for reducing laser power density and energy density, avoid integrating sphere impaired, can as shown in Figure 2 reflective convex mirror 4 be set on the laser optical path in integrating sphere.

The test luminous efficiency of photoluminescent body, concrete steps are:

The first step: select different sampling receptacles at different samples, solid sample selects bulk sample anchor clamps, pulverized specimen to select sample cell, and liquid sample is selected sample cell, and sampling receptacle is fixed on the sample stage;

Second step: with the relative spectral sensitivity S (λ) of standard lamp calibration measurement device;

The 3rd step: sampling receptacle not setting-out earlier product, measure excitation spectrum La (λ) with fiber laser

The 4th step: sampling receptacle is put into sample, with the fluorescence spectrum Y (λ) and the remaining exciting light spectrum Lb (λ) of fiber laser measuring samples generation

The 5th step: calculate total photon number A that exciting light sends by formula (2),

$A=\∫\frac{\mathrm{La}\left(\mathrm{\λ}\right)}{s\left(\mathrm{\λ}\right)}\frac{\mathrm{\λ}}{\mathrm{hc}}\mathrm{d\λ}---\left(2\right)$

In the formula, h is a Planck's constant, and c is the light velocity, and limit of integration is by the excitation wavelength decision of sample.

Calculate the photon number B that luminescent material absorbs by formula (3),

$B=\∫\frac{\mathrm{La}\left(\mathrm{\λ}\right)-\mathrm{Lb}\left(\mathrm{\λ}\right)}{s\left(\mathrm{\λ}\right)}\frac{\mathrm{\λ}}{\mathrm{hc}}\mathrm{d\λ}---\left(3\right)$

In the formula, h is a Planck's constant, and c is the light velocity, and limit of integration is by the excitation wavelength decision of sample.

Count C by the fluorescent photon that formula (4) calculating luminescent material sends,

$C=\∫\frac{Y\left(\mathrm{\λ}\right)}{s\left(\mathrm{\λ}\right)}\frac{\mathrm{\λ}}{\mathrm{hc}}\mathrm{d\λ}---\left(4\right)$

In the formula, h is a Planck's constant, and c is the light velocity, and limit of integration is by the fluorescence spectrum wavelength decision of the required sample of reality.

By the fluorescence internal quantum efficiency of formula (5) calculating luminescent material,

By the fluorescence external quantum efficiency of formula (6) calculating luminescent material,

Claims (3)

1, a kind of device of measuring luminous efficiency of photoluminescent body, it is characterized in that comprising the integrating sphere (3) of band optic fibre input end and output terminal, the fiber laser (1) and the calibration standard lamp (2) that are connected with integrating sphere (3) input end, integrating sphere (3) internal fixation has sample stage (5) and is used to block the shelves that fluorescence that luminescent material sends directly do not penetrate from the integrating sphere output terminal does not pull (9), the output terminal of integrating sphere (3) links to each other with spectrophotometer (10) input end, and the output terminal of spectrophotometer (10) links to each other with computer (11).

2, the device of measurement luminous efficiency of photoluminescent body according to claim 1 is characterized in that shelves pull and scribble the coating identical with the integrating sphere inwall on (9).

3, the device of measurement luminous efficiency of photoluminescent body according to claim 1 is characterized in that being provided with on the light path in integrating sphere reflective convex mirror (4).

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