LED光学设计.pdf

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高功率高功率高功率高功率LEDLEDLEDLED之光 Reflector TIR
Lens
Made from standard commodity plastic
resins that are very inexpensive
X
Made from optical grade plastics (PMMA) X
that are very expensive.
Fairly simple to design and the tooling is
inexpensive. Basic injection molding. Yields
thousands / hour X
Very complex to manufacture, which makes
the design and tooling very expensive.
Unlike reflectors, these molds need to be X
run in high precision molding machines.
Yields hundreds of parts / hourHowHow toto choosechoose thethe LensLens YouYou NeedNeedRadiationRadiation PatternsPatterns
• Batwing radiation pattern
– For even illumination of a flat surface
– Intended to be used in Traffic Signals
• Lambertian radiation pattern
– For general purpose
– same source size from all angles
– point source
• Side Emitter
– In combination with Reflectors
– Coupling into WaveguidesBatwingBatwing radiationradiation patternpattern
Α Α > Α [ m
] 100%
1 2 1 90%
80%
b a a=cos(ϕ) *b 70%
ϕ ϕ 60%
50%
40%
Ω1 30%
20%
Relative Intensity (%)
d 10%
1 Ω = Ω [ sr ] 0%
2 1 -100 -80 -60 -40 -20 0 20 40 60 80 100
x [m] Angular Displacement (Degrees)
Iv [cd] = [lm/sr] (Intensity)
2
~ cos( ϕ)^-3 ϕ [°]
Ev [lx] = [lm/m淫 (Illuminance)
3
x [m] : S