Developments in TEM for life-science research

1994 ◽  
Vol 52 ◽  
pp. 514-515
Author(s):  
U. Lücken ◽  
Wim M. Busing ◽  
Michael Felsmann ◽  
Frank de Jong ◽  
Max T. Otten
Keyword(s):  
Life Science ◽  
Materials Science ◽  
Focal Length ◽  
Science Research ◽  
Objective Lens ◽  
High Contrast ◽  
Contrast Imaging ◽  
Low Contrast ◽  
High Contrast Imaging ◽  
Small Spot

The study of Life Science materials with the TEM faces a number of problems such as low contrast in unstained specimens and specimen sensitivity to electron-beam damage and poor vacuum. Providing solutions to these problems has been the basis for several new developments on the Philips CM-series TEMs.Objective lenses traditionally have been optimised for parameters that are important in materials science: high resolution and very small spot sizes. With these parameters comes a short focal length which reduces the contrast from the specimen - no problem in the high-contrast materials science specimens, but highly problematic in the case of low-contrast biological specimens. A new objective lens - the BioTWIN - has been developed specifically for high-contrast imaging and analysis of biological specimens. Its long focal length (6.2 mm; 2 to 3 times larger than that of a typical materials science objective lens) ensures high contrast by enabling the removal of the majority of elastically and inelastically scattered electrons by the objective aperture. Figure 1 shows a comparison of images of a stained section imaged at low magnification, recorded with a TWIN and a BioTWIN lens.

The CM120 Biotwin: a high-contrast objective lens, optimum cryo-vacuum and improved EDX performance

1995 ◽  
Vol 53 ◽  
pp. 584-585
Author(s):  
Uwe Lücken ◽  
Michael Felsmann ◽  
Wim M. Busing ◽  
Frank de Jong
Keyword(s):  
Life Science ◽  
Focal Length ◽  
Objective Lens ◽  
High Contrast ◽  
Contrast Imaging ◽  
X Ray ◽  
Forming Mechanism ◽  
Similar Image ◽  
High Contrast Imaging ◽  
Low Concentrations

A new microscope for the study of life science specimen has been developed. Special attention has been given to the problems of unstained samples, cryo-specimens and x-ray analysis at low concentrations.A new objective lens with a Cs of 6.2 mm and a focal length of 5.9 mm for high-contrast imaging has been developed. The contrast of a TWIN lens (f = 2.8 mm, Cs = 2 mm) and the BioTWTN are compared at the level of mean and SD of slow scan CCD images. Figure 1a shows 500 +/- 150 and Fig. 1b only 500 +/- 40 counts/pixel. The contrast-forming mechanism for amplitude contrast is dependent on the wavelength, the objective aperture and the focal length. For similar image conditions (same voltage, same objective aperture) the BioTWIN shows more than double the contrast of the TWIN lens. For phasecontrast specimens (like thin frozen-hydrated films) the contrast at Scherzer focus is approximately proportional to the √ Cs.

The CM120-Biofiiter: Digital Imaging Of Frozen Hydratedspecimens and Elemental Mapping

1998 ◽  
Vol 4 (S2) ◽  
pp. 398-399
Author(s):  
U. Lücken ◽  
AF. de Jong ◽  
M. Kundmann ◽  
D. Chemy ◽  
R. Leapman
Keyword(s):  
Digital Image ◽  
Low Dose ◽  
Ease Of Use ◽  
Objective Lens ◽  
High Contrast ◽  
Contrast Imaging ◽  
Image Recording ◽  
High Contrast Imaging ◽  
Computer Controlled ◽  
Digital Image Recording

A new system for energy-filtered electron microscopy (EFTEM) has been developed, adapted for the study of life science specimens. Special attention has been given to integration, ease of use and the typical problems encountered while investigating unstained and cryo-specimens. Low-dose, cryocapabilities and a high-contrast objective lens have been combined with an imaging energy filter, digital image recording with phosphor scintillator and advanced image-processing capabilities. The CM120-BioFilter is an integration of the CM120-BioTWIN or the CM120TWIN with the Gatan postcolumn imaging filter GIF100. The BioTWIN objective lens (Cs=6.2 mm, f=5.9 mm) is optimized for high-contrast imaging. The TWIN lens(Cs=2mm,f=2.8mm) is optimized for high resolution in structural biology. The GIF 100 is a computer-controlled, second-order corrected energy filter with a cooled multiscan CCD for digital image recording. Improvement of the contrast can be achieved if inelastically scattered electrons are removed.

The CM120-Biofilter: Digital Imaging of Unstained Specimen, a Comparison of Zero-Loss and Unfiltered Images

1996 ◽  
Vol 54 ◽  
pp. 422-423
Author(s):  
Uwe Lücken ◽  
A. Frank de Jong ◽  
Wim M. Busing ◽  
Jeremy Rees ◽  
Klaus Nadarzinski ◽  
...  
Keyword(s):  
Digital Image ◽  
Ease Of Use ◽  
Objective Lens ◽  
High Contrast ◽  
Contrast Imaging ◽  
Spleen Tissue ◽  
Image Recording ◽  
High Contrast Imaging ◽  
Computer Controlled ◽  
Digital Image Recording

A new system for energy-filtered electron microscopy (EFTEM) has been developed, adapted for the study of life science specimens. Attention has been given to integration, ease of use and the typical problems encountered while investigating unstained and cryo-specimens. Low-dose, cryo-capabilities and a high contrast objective lens have been combined with an imaging energy filter, digital image recording with phosphorus scintillator and advanced image processing capabilities. The CM120-BioFilter is an integration of the CM 120-BioTWIN with the Gatan post-column imaging filter GIF100. The BioTWIN objective lens (Cs=6.2 mm, f=5.9 mm) is optimized for high-contrast imaging. The GIF100 is a computer-controlled, second- order corrected energy filter with a cooled multiscan CCD for digital image recording. Improvement of the contrast can be achieved if inelastically scattered electrons are removed. A comparison of zero-loss filtered and unfiltered images from unstained specimens is presented.The contrast of thick, unstained specimens is limited by the high amount of inelastic scattering. Images from thick sections of unstained spleen tissue shown in Fig. 1 are compared by means of mean and standard deviation of multiscan CCD data.

scholarly journals Planar photonic chips with tailored angular transmission for high-contrast-imaging devices

2021 ◽  
Author(s):  
Yan Kuai ◽  
Junxue Chen ◽  
Gang Zou ◽  
Joseph Lakowicz ◽  
Douguo Zhang
Keyword(s):  
Large Scale ◽  
Biological Species ◽  
High Contrast ◽  
Contrast Imaging ◽  
Imaging Device ◽  
Low Contrast ◽  
High Contrast Imaging ◽  
Brightfield Microscopy ◽  
Photonic Band ◽  
Microscopy Images

Abstract A limitation of standard brightfield microscopy is its low contrast images, especially for thin specimens of weak absorption, and biological species with refractive indices very close in value to that of their surroundings. Here, we demonstrate, using a planar photonic chip with tailored angular transmission as the sample substrate, a standard brightfield microscopy can provide both darkfield and total internal reflection (TIR) microscopy images with one experimental configuration. The image contrast is enhanced without altering the specimens and the microscope configurations. This planar chip consists of several multilayer sections with designed photonic band gaps and a central region with dielectric nanoparticles, which does not require top-down nanofabrication and can be fabricated in a large scale. The photonic chip eliminates the need for a bulky condenser or special objective to realize darkfield or TIR illumination. Thus, it can work as a miniaturized high-contrast-imaging device for the developments of versatile and compact microscopes.

scholarly journals Planar photonic chips with tailored angular transmission for high-contrast-imaging devices

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yan Kuai ◽  
Junxue Chen ◽  
Zetao Fan ◽  
Gang Zou ◽  
Joseph. R. Lakowicz ◽  
...  
Keyword(s):  
Total Internal Reflection ◽  
Biological Species ◽  
High Contrast ◽  
Contrast Imaging ◽  
Imaging Device ◽  
Low Contrast ◽  
High Contrast Imaging ◽  
Brightfield Microscopy ◽  
Photonic Band ◽  
Microscopy Images

AbstractA limitation of standard brightfield microscopy is its low contrast images, especially for thin specimens of weak absorption, and biological species with refractive indices very close in value to that of their surroundings. We demonstrate, using a planar photonic chip with tailored angular transmission as the sample substrate, a standard brightfield microscopy can provide both darkfield and total internal reflection (TIR) microscopy images with one experimental configuration. The image contrast is enhanced without altering the specimens and the microscope configurations. This planar chip consists of several multilayer sections with designed photonic band gaps and a central region with dielectric nanoparticles, which does not require top-down nanofabrication and can be fabricated in a larger scale. The photonic chip eliminates the need for a bulky condenser or special objective to realize darkfield or TIR illumination. Thus, it can work as a miniaturized high-contrast-imaging device for the developments of versatile and compact microscopes.

scholarly journals Anti-quenching NIR-II molecular fluorophores for in vivo high-contrast imaging and pH sensing

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Shangfeng Wang ◽  
Yong Fan ◽  
Dandan Li ◽  
Caixia Sun ◽  
Zuhai Lei ◽  
...  
Keyword(s):  
Ph Sensing ◽  
High Contrast ◽  
Contrast Imaging ◽  
High Contrast Imaging

Simulations of exoplanets detection obtained with a high-contrast imaging instrument: CHEOPS

2004 ◽  
Author(s):  
Alessandro Berton ◽  
Raffaele G. Gratton ◽  
Markus Feldt ◽  
Silvano Desidera ◽  
Elena Masciadri ◽  
...  
Keyword(s):  
High Contrast ◽  
Contrast Imaging ◽  
High Contrast Imaging ◽  
Imaging Instrument
Sign in / Sign up

Export Citation Format

Share Document