A New High-Speed Spray Processor for 16/35mm Black-and-White, Negative or Positive Film

1957 ◽  
Vol 66 (7) ◽  
pp. 419-421
Author(s):  
Edward V. Lewis
Keyword(s):  
1985 ◽  
Vol 107 (2) ◽  
pp. 206-219 ◽  
Author(s):  
R. A. Taylor

Two new scanning type cotton trashmeters are being developed to indicate the amount of trash and foreign matter in lint cotton. These instruments are primarily intended to replace the current visual method of grading cotton for market quality. They both perform a two dimensional surface scan using a black and white television camera. High-speed microprocessors provide an analysis of the TV signal at video scan rates. Only a fraction of a second of time is required to complete all scanning, signal processing, and data analysis for each cotton sample exposure. This article discusses some common problems in TV image analysis and how they relate to cotton scanning. Also discussed are instrument precision and design features and a method of calibrating each instrument.


2021 ◽  
Vol 59 ◽  
pp. 57-70
Author(s):  
Om Prakash Jasuja ◽  
Suryakant Mishra ◽  
Mohinder Singh

The present research was aimed at finding out the relative effect of advancement in photocopier technology on the analysis of handwriting line quality features in multi-generational photocopies. Five subsequent multi-generational photocopies of 50 signature samples from different individuals which were produced by 75 black and white photocopiers were used for line quality assessments. Variations in line quality features in different photocopy generations, such as: smooth edges or ragged edges, broken or continuous stroke, fine tapering changes, and some identification details of features like pen lifts, retouching, and hesitation were carefully observed in sample photocopies, which were recorded according to the brand and model of photocopier machines, as well as their size and speed. The results of the study revealed that raggedness in line was often observed in third generation (G3) and higher generations, in samples produced by some low speed copiers (copying speed < 30 cpm) or very high speed copiers (copying speed ≤ 80 cpm). However, their line quality was still found to be good enough for handwriting analysis up to the fifth generation (G5) in photocopy samples produced by some medium speed copiers (copying speed 30 to 50 cpm). It was, however, observed that, usually, continuity of line and smoothness of line were appreciably lost in G3 and higher generations in photocopies which were produced by portable desktop printers. Exceptionally, certain artifacts that are usually found in some higher generation copies were conspicuously absent in all photocopy generations (G1–G5) which were produced by some advanced third generation photocopiers. Hopefully, the information obtained from the study will be found useful to document examiners when examining certain cases involving multi-generations of photocopier reproductions.


1960 ◽  
Vol 69 (10) ◽  
pp. 742-744 ◽  
Author(s):  
F. W. Spangler ◽  
H. R. Beilfuss

1968 ◽  
Vol 77 (10) ◽  
pp. 1136-1136
Author(s):  
W. H. Bahler ◽  
M. L. Judd ◽  
F. W. Spangler ◽  
A. L. Williams

MRS Bulletin ◽  
1989 ◽  
Vol 14 (5) ◽  
pp. 17-22 ◽  
Author(s):  
Frederick C. Brown

The modern photographic emulsion is an extremely sensitive detector of light quanta. In fact, high speed black-and-white film (which consists mainly of microcrystalline grains of AgBr or AgBrI suspended in gelatin on an inert base) ranks with the photomultiplier tube as capable of detecting a very few individual light quanta. Exposure times can vary from minute fractions of a second to hours. Unlike the multiplier tube, the photographic emulsion also responds well to relatively high light flux, that is, film can have wide exposure latitude. In many respects such as sensitivity, latitude, resolution, etc., film sets the pace as new multiplier tubes and charge-coupled devices are developed.Of course, the high sensitivity of film comes about because light absorbed within an emulsion grain causes a latent image to be formed (usually on the surface), which then renders the entire grain developable. The tabular grains of a modern high speed emulsion are largely triangular or hexagonal single-crystal platelets approximately 10 ü across and 0.1 ü thick. Such a grain will contain about 109 silver atoms, and it can be sensitized by a few molecules of gold sulfide or other additives adsorbed on its surface.In the concentration speck theory of the latent image, light is absorbed throughout the grain, but this energy is transported by the motion of electrons to a sensitivity center usually on the surface where the latent image is formed.


2007 ◽  
Vol 364-366 ◽  
pp. 827-831
Author(s):  
Mika Aikio ◽  
Hannu Lindström ◽  
Eveliina Juntunen ◽  
Kari Kataja ◽  
Heimo Keränen

High speed imaging with decent image quality is difficult because the available exposure times are very short, which leads to the usage of a large aperture. Unfortunately, large aperture also decreases the depth resolution of the system, which reduces the quality of the image. Thus the source of illumination has to be able to output a high amount of energy in a very short time so that the aperture requirement can be relaxed. There are only a few Xenon flash lamps that fulfill the requirement of sub-microsecond pulses, so the natural choice would be to use lasers. However, when the target surface is rough, high degree of coherence causes black and white interference patterns known as speckle. The sensor might register irradiance values from zero to saturated state. Needless to say, this reduces drastically the quality of the image. There is variety of techniques for speckle removal, ranging from chaotic laser states to digital signal processing [1-5]. In this paper we discuss an alternative, namely LEDs, for this kind of illumination. The authors have performed some experiments and theoretical modeling, and successfully demonstrated an illumination system based on LEDs that can output enough energy to enable imaging with pulse lengths of 100 ns.


TAPPI Journal ◽  
2012 ◽  
Vol 11 (2) ◽  
pp. 33-39
Author(s):  
MELUR K. RAMASUBRAMANIAN ◽  
RICHARD A. VENDITTI ◽  
PRADEEP K. GILLELLA

Sorting paper into compatible grades is a necessary step before recycling. Current methods of man¬ually sorting are tedious, slow, and expensive. High-speed automation of the sorting process will improve the cost efficiency and increase the amount of paper recycled significantly. Correct identification of the sample in real-time before the sample reaches the actuation station still remains a challenge because different types of paper and board samples are mixed in a waste stream, and have a lot of variation in terms of color, chemical composition, coating, and printing in black and white and color to different degrees. This primarily is because of a lack of satisfactory sen¬sors and sensor fusion algorithms for sample identification in real-time. In this paper, we identify key parameters that must be measured, discuss a sensor system design, and describe integration of the output from sensors to interpret the type of sample using a fuzzy inference algorithm. Results show that the sensor system proposed is capable of identifying the samples at 90% accuracy compared to manual identification. The sensor system can be integrated onto a conveyor and actuation system for automated sorting.


2020 ◽  
Vol 34 (2) ◽  
pp. 438-450
Author(s):  
Sadiye Keleş ◽  
Özlem Yurt

The aim of the study is to evaluate the relationship between early childhood teachers’ risky play experiences, their injury histories in their childhood and risky play management strategies they used as a teacher. 190 early childhood teachers participated in this study. Data were collected through a semi- structured interview form. Only play with great heights (climbing up a tree) and play with high speed (swinging on playground swings) were included in the semi-structured interview form. Scenario-based, black and white drawings were used as a data collection tool. Results showed that teachers’ risky play histories, injury histories and their management strategies at play with great heights are independent of each other. However, a different pattern was identified for play with high speed (swinging on playground swings).  This result provides an opportunity to discuss whether teachers’ injury histories at specific risky play categories, may affect their risky play management strategies.


1968 ◽  
Vol 77 (10) ◽  
pp. 1051-1052 ◽  
Author(s):  
Warren W. Evans

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