Stabilization of imprint’s optical parameters in offset printing

2021 ◽  
Author(s):  
Yaroslav Zorenko ◽  
Vasyl Skyba
Author(s):  
R. Hegerl ◽  
A. Feltynowski ◽  
B. Grill

Till now correlation functions have been used in electron microscopy for two purposes: a) to find the common origin of two micrographs representing the same object, b) to check the optical parameters e. g. the focus. There is a third possibility of application, if all optical parameters are constant during a series of exposures. In this case all differences between the micrographs can only be caused by different noise distributions and by modifications of the object induced by radiation.Because of the electron noise, a discrete bright field image can be considered as a stochastic series Pm,where i denotes the number of the image and m (m = 1,.., M) the image element. Assuming a stable object, the expectation value of Pm would be Ηm for all images. The electron noise can be introduced by addition of stationary, mutual independent random variables nm with zero expectation and the variance. It is possible to treat the modifications of the object as a noise, too.


Author(s):  
Norio Baba ◽  
Norihiko Ichise ◽  
Syunya Watanabe

The tilted beam illumination method is used to improve the resolution comparing with the axial illumination mode. Using this advantage, a restoration method of several tilted beam images covering the full azimuthal range was proposed by Saxton, and experimentally examined. To make this technique more reliable it seems that some practical problems still remain. In this report the restoration was attempted and the problems were considered. In our study, four problems were pointed out for the experiment of the restoration. (1) Accurate beam tilt adjustment to fit the incident beam to the coma-free axis for the symmetrical beam tilting over the full azimuthal range. (2) Accurate measurements of the optical parameters which are necessary to design the restoration filter. Even if the spherical aberration coefficient Cs is known with accuracy and the axial astigmatism is sufficiently compensated, at least the defocus value must be measured. (3) Accurate alignment of the tilt-azimuth series images.


Author(s):  
F.A. Ponce ◽  
H. Hikashi

The determination of the atomic positions from HRTEM micrographs is only possible if the optical parameters are known to a certain accuracy, and reliable through-focus series are available to match the experimental images with calculated images of possible atomic models. The main limitation in interpreting images at the atomic level is the knowledge of the optical parameters such as beam alignment, astigmatism correction and defocus value. Under ordinary conditions, the uncertainty in these values is sufficiently large to prevent the accurate determination of the atomic positions. Therefore, in order to achieve the resolution power of the microscope (under 0.2nm) it is necessary to take extraordinary measures. The use of on line computers has been proposed [e.g.: 2-5] and used with certain amount of success.We have built a system that can perform operations in the range of one frame stored and analyzed per second. A schematic diagram of the system is shown in figure 1. A JEOL 4000EX microscope equipped with an external computer interface is directly linked to a SUN-3 computer. All electrical parameters in the microscope can be changed via this interface by the use of a set of commands. The image is received from a video camera. A commercial image processor improves the signal-to-noise ratio by recursively averaging with a time constant, usually set at 0.25 sec. The computer software is based on a multi-window system and is entirely mouse-driven. All operations can be performed by clicking the mouse on the appropiate windows and buttons. This capability leads to extreme friendliness, ease of operation, and high operator speeds. Image analysis can be done in various ways. Here, we have measured the image contrast and used it to optimize certain parameters. The system is designed to have instant access to: (a) x- and y- alignment coils, (b) x- and y- astigmatism correction coils, and (c) objective lens current. The algorithm is shown in figure 2. Figure 3 shows an example taken from a thin CdTe crystal. The image contrast is displayed for changing objective lens current (defocus value). The display is calibrated in angstroms. Images are stored on the disk and are accessible by clicking the data points in the graph. Some of the frame-store images are displayed in Fig. 4.


TAPPI Journal ◽  
2012 ◽  
Vol 11 (10) ◽  
pp. 9-17
Author(s):  
ALESSANDRA GERLI ◽  
LEENDERT C. EIGENBROOD

A novel method was developed for the determination of linting propensity of paper based on printing with an IGT printability tester and image analysis of the printed strips. On average, the total fraction of the surface removed as lint during printing is 0.01%-0.1%. This value is lower than those reported in most laboratory printing tests, and more representative of commercial offset printing applications. Newsprint paper produced on a roll/blade former machine was evaluated for linting propensity using the novel method and also printed on a commercial coldset offset press. Laboratory and commercial printing results matched well, showing that linting was higher for the bottom side of paper than for the top side, and that linting could be reduced on both sides by application of a dry-strength additive. In a second case study, varying wet-end conditions were used on a hybrid former machine to produce four paper reels, with the goal of matching the low linting propensity of the paper produced on a machine with gap former configuration. We found that the retention program, by improving fiber fines retention, substantially reduced the linting propensity of the paper produced on the hybrid former machine. The papers were also printed on a commercial coldset offset press. An excellent correlation was found between the total lint area removed from the bottom side of the paper samples during laboratory printing and lint collected on halftone areas of the first upper printing unit after 45000 copies. Finally, the method was applied to determine the linting propensity of highly filled supercalendered paper produced on a hybrid former machine. In this case, the linting propensity of the bottom side of paper correlated with its ash content.


TAPPI Journal ◽  
2010 ◽  
Vol 9 (10) ◽  
pp. 7-15
Author(s):  
HANNA KOIVULA ◽  
DOUGLAS BOUSFIELD ◽  
MARTTI TOIVAKKA

In the offset printing process, ink film splitting has an important impact on formation of ink filaments. The filament size and its distribution influence the leveling of ink and hence affect ink setting and the print quality. However, ink filaments are difficult to image due to their short lifetime and fine length scale. Due to this difficulty, limited work has been reported on the parameters that influence filament size and methods to characterize it. We imaged ink filament remains and quantified some of their characteristics by changing printing speed, ink amount, and fountain solution type. Printed samples were prepared using a laboratory printability tester with varying ink levels and operating settings. Rhodamine B dye was incorporated into fountain solutions to aid in the detection of the filaments. The prints were then imaged with a confocal laser scanning microscope (CLSM) and images were further analyzed for their surface topography. Modeling of the pressure pulses in the printing nip was included to better understand the mechanism of filament formation and the origin of filament length scale. Printing speed and ink amount changed the size distribution of the observed filament remains. There was no significant difference between fountain solutions with or without isopropyl alcohol on the observed patterns of the filament remains.


2004 ◽  
Vol 9 (4) ◽  
pp. 363-372 ◽  
Author(s):  
T. Lukaszewicz ◽  
A. Ravinski ◽  
I. Makoed

A new multilayer electrochromic device has been constructed according to the following pattern: glass1/ITO/WO3/gel electrolyte/BP/ITO/glass2, where ITO is a transparent conducting film made of indium and tin oxide and with the surface resistance equal 8–10 Ω/cm2 . The electrochromic devices obtained in the research are characterized by great (considerable) transmittance variation between coloration and bleaching state (25–40% at applied voltage of 1.5 to 3 V), and also high coloration efficiency (above 100 cm2 /C). Selfconsistent energy bands, dielectric permittivity and optical parameters are calculated using a full-potential linear muffin-tin orbital method. The numerical solution of the Debye-Smoluchowski equations is developed for simulating recombination probability of Li+ ions in amorphous electrolyte.


2002 ◽  
Vol 8 (2-3) ◽  
pp. 231-238
Author(s):  
G.K. Korotaev ◽  
◽  
M.E. Li ◽  
G.A. Tolkachenko ◽  
◽  
...  

Author(s):  
I. P. Studenyak ◽  
A. V. Bedak ◽  
V. Yu. Izai ◽  
А. М. Solomon ◽  
P. Kúš ◽  
...  
Keyword(s):  

2019 ◽  
Vol 70 (10) ◽  
pp. 3538-3544
Author(s):  
Alina Costina Luca ◽  
Ana Cezarina Morosanu ◽  
Irina Macovei ◽  
Dan Gheorghe Dimitriu ◽  
Dana Ortansa Dorohoi ◽  
...  

Electro-optical parameters of fluorescein molecule in the second excited electronic state and information on the interactions with solvents were obtained from a solvatochromic study. Parameters of the solvents such as the refractive index, electrical permittivity and Kamlet-Taft parameters (hydrogen bond acidity and basicity) were related with the experimentally recorded shifts of UV absorption spectral band of fluorescein dissolved in several solvents. Through a variational method, the electric dipole moment and polarizability in excited state of fluorescein molecule were estimated. The calculus requires some parameters of the fluorescein molecule in the ground electronic state, which were determined through a quantum-mechanical study.


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