DESIGN,FABRICATION AND EVALUATION OF A HYBRID DIFFRACTIVE REFRACTIVE ACHROMAT

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DESIGN,FABRICATION AND EVALUATION OF A HYBRID
DIFFRACTIVE REFRACTIVE ACHROMAT

• Kiran Yeruva

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Introduction

• Image formation by converging lens
• Chromatic aberration
• Doublet
• Removal Of aberration
• Doublet Fabrication
• Photo resist lithography
• Binary structure efficiency
• Advantage of Hybrid structures

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Geometrical Optics

• Image formed by Converging Lens

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Chromatic Aberration

• Different colors are focused at different
  distances along the axis

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Doublet Lens
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Image formed by singlet,doublet
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Doublet Image
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Beam Separation Reduction
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Removal of aberration

• With crown and flint glass combination chromatic
  aberration is removed

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• Zone Plate

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Kinoform
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Photo resist etching
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Lens with kinoform
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SEM image of etched surface
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Binary Efficiency
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Doublet lens etching
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Reduction of Chromatic aberration
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Conclusions

• Hybrid Doublet lens removes chromatic aberration
• It is more efficient than a singlet
• By photo resist method we can reach 100
  efficiency
• A complicated lens system can be reduced to a
  simple lens system

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References

• Design, Fabrication, Evaluation of hybrid
  diffractive refractive achromat By Neil Emerton
  ieee publication
• www.wikipedia.org
• Optics- Euguene Hecht

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THANK YOU

• Have a Nice Day