Wide-angle zoom lens with removed forward entrance pupil

1998 ◽  
Author(s):  
Irina L. Livshits-Anitropova ◽  
Michael M. Russinov ◽  
Igor G. Bronchtein
Keyword(s):  
2013 ◽  
Vol 60 (9) ◽  
pp. 2603-2613 ◽  
Author(s):  
Tung-Ying Lee ◽  
Tzu-Shan Chang ◽  
Chen-Hao Wei ◽  
Shang-Hong Lai ◽  
Kai-Che Liu ◽  
...  

1974 ◽  
Author(s):  
Karl M. Bystricky ◽  
Paul R. Yoder, Jr.
Keyword(s):  

Author(s):  
R. W. Carpenter ◽  
I.Y.T. Chan ◽  
J. M. Cowley

Wide-angle convergent beam shadow images(CBSI) exhibit several characteristic distortions resulting from spherical aberration. The most prominent is a circle of infinite magnification resulting from rays having equal values of a forming a cross-over on the optic axis at some distance before reaching the paraxial focal point. This distortion is called the tangential circle of infinite magnification; it can be used to align and stigmate a STEM and to determine Cs for the probe forming lens. A second distortion, the radial circle of infinite magnification, results from a cross-over on the lens caustic surface of rays with differing values of ∝a, also before the paraxial focal point of the lens.


Author(s):  
L. T. Germinario ◽  
J. Blackwell ◽  
J. Frank

This report describes the use of digital correlation and averaging methods 1,2 for the reconstruction of high dose electron micrographs of the chitin-protein complex from Megarhyssa ovipositor. Electron microscopy of uranyl acetate stained insect cuticle has demonstrated a hexagonal array of unstained chitin monofibrils, 2.4−3.0 nm in diameter, in a stained protein matrix3,4. Optical diffraction Indicated a hexagonal lattice with a = 5.1-8.3 nm3 A particularly well ordered complex is found in the ovipositor of the ichneumon fly Megarhyssa: the small angle x-ray data gives a = 7.25 nm, and the wide angle pattern shows that the protein consists of subunits arranged in a 61 helix, with an axial repeat of 3.06 nm5.


1987 ◽  
Vol 32 (1) ◽  
pp. 54-55
Author(s):  
Jack P. Shonkoff

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