Ghost reflection of testing long focal length lens with computer-generated hologram

A method for testing the transmitted wavefront of large aperture long-focal-length lens with a multizone computer-generated hologram (CGH) is proposed. The multizone CGH has 5 zones: one main zone for the null testing of long-focal-length lens and four auxiliary zones for the pre-alignment of measured lens. Both 1st order wavefront and 0th order wavefront of CGH are measured, and 0th order wavefront is used to calibrate the substrate error. To verify this test approach, a 450mm×450mm multizone CGH is designed and fabricated for testing the spatial filter lens. Experiments and error analysis are carried out. The results show that the desired precision can be reached with use of CGH.

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Testing the transmitted wavefront of large aperture and long-focal-length lens with computer-generated hologram

Optics Express ◽

10.1364/oe.26.028067 ◽

2018 ◽

Vol 26 (21) ◽

pp. 28067 ◽

Cited By ~ 1

Author(s):

Jian-Peng Cui ◽

Ning Zhang ◽

Jie Liu ◽

Di-Long Wu ◽

Hua Xu ◽

...

Keyword(s):

Focal Length ◽

Large Aperture ◽

Computer Generated Hologram ◽

Focal Length Lens

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Short focal length lens array based on liquid crystal material with large Δn

Chinese Journal of Liquid Crystals and Displays ◽

10.37188/cjlcd.2020-0288 ◽

2021 ◽

Vol 36 (4) ◽

pp. 509-515

Author(s):

Rui LI ◽

◽

Qiong-hua WANG ◽

Keyword(s):

Liquid Crystal ◽

Focal Length ◽

Lens Array ◽

Crystal Material ◽

Focal Length Lens ◽

Liquid Crystal Material ◽

Short Focal Length

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IR femtosecond pulsed laser-based fiber Bragg grating inscription in a photonic crystal fiber using a phase mask and a short focal length lens

Optics Express ◽

10.1364/oe.26.014741 ◽

2018 ◽

Vol 26 (11) ◽

pp. 14741 ◽

Cited By ~ 4

Author(s):

Tigran Baghdasaryan ◽

Thomas Geernart ◽

Adriana Morana ◽

Emmanuel Marin ◽

Sylvain Girard ◽

...

Keyword(s):

Photonic Crystal ◽

Fiber Bragg Grating ◽

Photonic Crystal Fiber ◽

Focal Length ◽

Pulsed Laser ◽

Phase Mask ◽

Bragg Grating ◽

Crystal Fiber ◽

Focal Length Lens ◽

Short Focal Length

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Variable focal-length lens for atoms

Journal of the Optical Society of America B ◽

10.1364/josab.13.000257 ◽

1996 ◽

Vol 13 (2) ◽

pp. 257 ◽

Cited By ~ 1

Author(s):

Qiming Li ◽

K. G. H. Baldwin ◽

H.-A. Bachor ◽

D. E. McClelland

Keyword(s):

Focal Length ◽

Focal Length Lens

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A 100 KV Transmission Scanning Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100064165 ◽

1971 ◽

Vol 29 ◽

pp. 22-23

Author(s):

A. V. Crewe

Keyword(s):

Focal Length ◽

Electron Gun ◽

Objective Lens ◽

Scanning Microscope ◽

Parallel Beam ◽

Condenser Lens ◽

Focal Length Lens ◽

Short Focal Length ◽

Pass Through ◽

Correction System

A 100 kv transmission scanning microscope is now being constructed which should have a point resolution of 2.5 to 3 Å. The design of this microscope is similar to the design of our existing 30 kv 5 Å microscope, but there are several significant changes which are based upon some difficulties and sources of inflexibility of that microscope.A field emission electron gun of our usual design will be used as the source of electrons, the only difference being that the spacing between the anodes has been increased from 2 to 3 cm. The electron beam will then pass through a condenser lens which will produce a parallel beam of electrons. This parallel beam will then be focused onto the specimen by means of a short focal length lens (approximately 1 mm focal length). The reason for using a condenser lens to produce the parallel beam of electrons is that in the future a quadrupole-octupole correction system will be installed in this section of the microscope in order to attempt to correct the spherical aberrations of the objective lens and thereby improve its resolution.

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