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1、发光器件的测量,NRC INMS PAR Measurement CourseWeb Instruments,光度学和辐射度学的基本概念,A 辐射能通量（辐射功率，单位：瓦 W）辐射能通量的谱密度,辐射能通量的谱密度：,视见函数,定义：,当= 555 nm 时，V=1,实验表明：,= 400 nm,a 光通量,光源发出的辐射能通量通过视见函数的权重因子折合成对人眼起作用的有效视觉强度称为光通量。单位：流明 lm,有：,或者：,最大光功当量，,1 lumen = 1/683 W at 555 nm,From a quantum mechanic perspective of photon flo
2、w rate and photon energy (E) at 555 nm,This is what 1 lumen is equivalent to.,b 发光强度 和 B 辐射强度,点光源发光强度,Radiometric Intensity is the radiometric flux density (watts) per steradian (W/sr),Photometric (luminous) intensity is the luminous flux density per steradian expressed in candellas.,Exponential Int
3、ensity Source: profiles radiation patterns of LEDs, both wide and and narrow beam widths.,Where n is the radiation exponent,c 亮度和 C 辐射亮度,亮度：,辐射亮度：,d 照度和 D 辐射照度,(光)照度定义：,，,单位：lux, lx,辐射照度定义：,单位：W/m2,watts per square meter,，,点光源的照度,，,面光源的照度,注意： （a）通常情况下光强的概念与这里的辐射 照度的概念一致，单位是W/cm2 。（b）照度是接收的概念，发光强度 和亮
4、度是发射的概念。,Some Typical Luminance And Radiance Levels,视见函数,400,500,600,700,800,0,1,1.8,Wavelength, nm,Photopic Sensitivity,y,This curve shows the relative sensitivity of the eye. To convert to photometric units from radiometric, multiply by 683 Lumens Per Watt,Color: Tristimulus Values,Describe Eyes R
5、esponse to ColorBased on Color Matching ExperimentsSmall Number of ObserversLines are Approximations,Spectral radiance Le(), the usual units are Watt/steradian/m2/nm,PR-705,Radiance(watts/sr/m2)3802.846e-0033821.285e-0023842.987e-0023863.336e-0023881.459e-0023901.739e-0023921.675e-0023944.251e-00339
6、61.720e-0023982.580e-0024002.076e-0024025.027e-0034041.362e-0024063.447e-0024083.644e-0024105.342e-0024128.716e-0024141.359e-0014161.861e-0014182.458e-0014203.686e-001,PhotometryObserver: 2 degreesLuminance(cd/m2)8.138e+004Luminance(fl) 2.375e+004Scotopic Y(cd/m2)9.670e+004Scotopic Y(fl) 7.025e+004P
7、ho. Transmit. (%)N/APho. Reflect. (%)N/APho. Opt. DensityN/APho. AbsorptanceN/AObserver: 10 degreesLuminance(cd/m2)9.088e+004Luminance(fl) 2.652e+004Pho. Transmit. (%)N/APho. Reflect. (%)N/APho. Opt. DensityN/APho. AbsorptanceN/A,RadiometryRadiance(watts/sr/m2) 3.393e+002Photon Rad.(photons/sr/m2/se
8、c) 8.782e+020Rad. Transmit. (%) N/ARad. Reflect (%) N/ARad. Opt. Density N/ARad. Absorptance N/A,ChromaticityObserver: 2 degreesX 9.101e+004Y 8.138e+004Z 1.832e+005CCT 91020MK -1 11.0u-v Dev -0.0153x 0.2559y 0.2289u 0.1956v 0.2623u 0.1956v 0.3935Observer: 10 degrees,Avantes 光纤光谱仪一个光子的能量：E = hc/ （J）
9、其中h = Plancks constant (6.626 10-34 Js)c = Speed of light (2.998108 ms-1)= Wavelength (m)一个焦耳的光子数 the number of photons per joule is:（in nm）5.0341015 1 mol = 6.023081023 (Number of Avogadro)1 mol = 6.023081017,单位换算 1 Watt/cm2 = 1 Joule/s/cm2 = 0.01 Joule/s/m2 0.01(nm)5.0341015/6.02308/1017 Mol/(sm2)
10、 =(nm)0.0000835785 Mol/(sm2) The photon count distribution Mol/(sm2nm) shows the photon flux received per square meter. Other photon count units that can be calculated from this are: Mol/(snm) photon flux received at diffuser surface Mol/( m2nm) photons received per square meter during one integrati
11、on cycle Mol/nm photons received at diffuser surface during one integration cycleIlluminance曲线 lm/m2或lux =测量的Irradiance曲线 Watt/cm2 0.01683视见函数Photometry 文件的表中：Illuminance值Illuminance曲线下积分（380nm780nm）Luminous Flux (r探头收到的) Lumen = Illuminance曲线 lm/m2 积分 探头接收面积m2,单色仪,透射谱测量 Transmittance,反射谱测量 Reflectance,吸收谱测量 Absorbance,人有了知识，就会具备各种分析能力，明辨是非的能力。所以我们要勤恳读书，广泛阅读，古人说“书中自有黄金屋。”通过阅读科技书籍，我们能丰富知识，培养逻辑思维能力；通过阅读文学作品，我们能提高文学鉴赏水平，培养文学情趣；通过阅读报刊，我们能增长见识，扩大自己的知识面。有许多书籍还能培养我们的道德情操，给我们巨大的精神力量，鼓舞我们前进。,
