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Patents: Diffractive Optic 2.0x & 1.8x Teleconverters

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tc2 - Patents: Diffractive Optic 2.0x & 1.8x Teleconverters
2.0x Teleconverter
tc18 - Patents: Diffractive Optic 2.0x & 1.8x Teleconverters
1.8x Teleconverter

Patent Publication No. 2011-123336

  • 2011.6.23 Release Date
  • 2009.12.11 filing date
  • Related 2011-123334

Example 1

  • f =- 124.47mm
  • = 1.95 magnification

Example 9

  • f =- 251.89mm
  • = 1.80 magnification
  • Rear attachment lens
  • Master a longer focal length
  • Smaller than the front converter
  • Because of the negative refractive power and degrade the curvature
  • Without a diaphragm
  • Beam passes through the upper and lower
  • Can not compensate for the aberrations caused by light passing through the off-axis
  • Magnification chromatic aberration only expanded
  • Correcting the axial chromatic aberration in the most object side lens group, to compensate for inadequate performance of the chromatic aberration and curvature of the most image-side lens group
  • Diffractive optics (DO lens = Diffractive Optics)
  • For example, the material is UV cured resin, wavelength 530nm design degree
  • Diffraction efficiency decreases at wavelengths other than orders for the design and will not require light fraction decreased, causing a flare
  • Transmittance is reduced when used in multiple locations

Patent Technology

  • Positive refractive power as a whole, group 4 consists
  • Applicable to telephoto and telephoto zoom
  • Share in compensating the chromatic aberration of magnification and lens and the next most image side lens
  • Multi-layer diffractive optical element
  • Than 95% diffraction efficiency across the visible light

Source [EG]

thanks Evgenii



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