Varifocal Lens
Varifocal Lens
Image of Varifocal Lens

KTN Innovative Optics: Elecro-optically activated. Best for bio-related fast laser microscopies.

*The top micrographs are two-photon images of C. elegans, kindly provided by Prof. Junichi Nakai and Dr. Keiko Gengyo-Ando, currently at Tohoku University. GFP was expressed in all neurons. Both microscope images are captured in two different imagining depths.

Varifocal Lens Inquiry



The focal-length can be shifted in a micro second by controlling the voltage to KTN crystal, which is 100 times faster than those of conventional varifocal lenses.

Focusing mechanism: Concept diagram


The focal-length shift performance

KTN Varifocal lens works as a convex lens and the focal-length is varied in proportion to the square o the supplied voltage.
The typical result of the lens power using the practical permittivity is 1.0 m−1 when 1 kV is applied.*

*Quoted from APPLIED OPTICS Vol. 51, No. 10 1 April 2012、APEX-4-022501.

Voltage vs Focal Point Shift Δf

Time response


Lens power 0 - 0.5m-1
Response frequency DC - 10kHz
Wavelength 488nm - 3500nm
Beam radius 3 mmφ
Size 97 mm x 85 mm x 32 mm

Custom-designed KTN VariFocal lenses are available.
Please feel free to contact us. 


3D microscopy setup (possible application)


Application examples

  • Biological microscopes, e.g., supporting nanometer-level resolution 3D living cell analysesa),b)
a) Klaus C. Gwosch, Jasmin K. Pape, Francisco Balzarotti, Philipp Hoess, Jan Ellenberg, Jonas Ries and Stefan W. Hell “MINFLUX nanoscopy delivers 3D multicolor nanometer resolution in cells”, Nature Methods, volume 17, 217–224, 2020.
b) Jasmin K. Pape, Till Stephan, Francisco Balzarotti, Rebecca Büchner, Felix Lange, Dietmar Riedel, Stefan Jakobs and Stefan W. Hell, “Multicolor 3D MINFLUX nanoscopy of mitochondrial MICOS proteins”, Proc. Natl. Acad. Sci. USA, published August 11, 2020.

  • Laser processing
  • 3D measurement (combined with KTN scanner)
Custom-designed KTN VariFocal lenses are available.
Please feel free to contact us. 


Varifocal Lens Inquiry

Related Link

Papers &Publications

Link page

Varifocal Lens Inquiry
Share on Twitter Share on Facebook