Constant fraction discriminator for fast high-precision pulsed TOF laser rangefinder

The purpose of a time discriminator is to decide when the input is something you are interested in. It does this by putting out a logic pulse when the input signal meets an adjustable threshold value. A low cost high performance constant fraction discriminator (CFD) for laser rangefinder using pulsed TOF (time of flight) is proposed with the accuracy been improved. The theory of CFD is deduced and discussed and a distance measuring system has been established and experimental evidence is presented to show the feasibility of solving the time walking error problem to amend the precision and improving the environmental applicability, the distance error of +/-0.5mm was observed in the lab condition. The advantages of this instrument are highlighted and the experimental results are presented.

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Software for the data-computing system of the high-precision laser rangefinder ?Hyperon-SLR?

Measurement Techniques ◽

10.1007/bf00980129 ◽

1994 ◽

Vol 37 (9) ◽

pp. 1021-1024

Author(s):

O. A. Bayuk ◽

M. Yu. Orlov ◽

O. V. Panyushkin ◽

A. V. Suetenko

Keyword(s):

High Precision ◽

Computing System ◽

Laser Rangefinder

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Construction Features of The High-Precision Laser Rangefinder Light Modulator

Journal of Architectural and Engineering Research ◽

10.54338/27382656-2021.1-5 ◽

2021 ◽

Vol 1 (1) ◽

pp. 26-31

Author(s):

Yegisabet Hakob Hayrapetyan ◽

Stepan Karen Petrosyan

Keyword(s):

High Precision ◽

Modulation Frequency ◽

Modulation Method ◽

Optical Effect ◽

Laser Rangefinder ◽

Light Modulator ◽

Phase Determination ◽

Modulation And Demodulation ◽

Determination Error ◽

Optical Crystal

The issues related to the development of a light modulator operating on the electro-optical effect of laser rangefinders by the modulation method are considered. To reduce the modulation power, it is proposed to lower the modulation frequency to 750-800 MHz, while simultaneously increasing the modulation quality to Q = 1000. The study of the phase determination error of a high-precision laser rangefinder depending on temperature showed that it is rational to construct the light modulator by radial installation of the KDP electro-optical crystal, with separated modulation and demodulation channels, while on combined resonators.

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Performance evaluation of fast, high precision laser rangefinder electronics with a pulsed laser

10.1117/12.912323 ◽

2011 ◽

Author(s):

David Vyhlídal ◽

Michal Jelínek ◽

Miroslav Čech ◽

Václav Kubeček

Keyword(s):

Performance Evaluation ◽

High Precision ◽

Pulsed Laser ◽

Laser Rangefinder

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Design of Optical System for Laser Rangefinder

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.187.581 ◽

2011 ◽

Vol 187 ◽

pp. 581-585

Author(s):

W.C. Wang

Keyword(s):

High Precision ◽

High Voltage ◽

Optical System ◽

Design Method ◽

Elevation Angle ◽

Laser Rangefinder ◽

Horizontal Angle ◽

Subdivision Algorithm

The principle and classes of grating sensors are analyzed in this paper firstly. To the high-precision requirement of rangefinder for the measurement of high voltage cables, the design method based on grating sensor is proposed. It is realized by installing two grating sensors on the rangefinder platform which are used for outputting the elevation angle and the horizontal angle. The subdivision circuit of system is described in detail by using E-subdivision algorithm. Experiment shows that it can increase the measure precision greatly.

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Automatic measurement of SAED patterns from asbestos minerals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106296 ◽

1988 ◽

Vol 46 ◽

pp. 846-847

Author(s):

J. C. Russ ◽

T. Taguchi ◽

P. M. Peters ◽

E. Chatfield ◽

J. C. Russ ◽

...

Keyword(s):

Diffraction Pattern ◽

High Precision ◽

Diffraction Data ◽

Automatic Measurement ◽

Automatic Method ◽

Important Method ◽

X Ray ◽

Integrated Intensity ◽

Asbestiform Minerals ◽

True Center

Conventional SAD patterns as obtained in the TEM present difficulties for identification of materials such as asbestiform minerals, although diffraction data is considered to be an important method for making this purpose. The preferred orientation of the fibers and the spotty patterns that are obtained do not readily lend themselves to measurement of the integrated intensity values for each d-spacing, and even the d-spacings may be hard to determine precisely because the true center location for the broken rings requires estimation. We have implemented an automatic method for diffraction pattern measurement to overcome these problems. It automatically locates the center of patterns with high precision, measures the radius of each ring of spots in the pattern, and integrates the density of spots in that ring. The resulting spectrum of intensity vs. radius is then used just as a conventional X-ray diffractometer scan would be, to locate peaks and produce a list of d,I values suitable for search/match comparison to known or expected phases.

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On effects of non-systematic reflections on weak-beam images of partial dislocations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087756 ◽

1991 ◽

Vol 49 ◽

pp. 688-689

Author(s):

K. Z. Botros ◽

S. S. Sheinin

Keyword(s):

High Precision ◽

Stacking Fault ◽

Important Application ◽

Stacking Fault Energy ◽

Sharp Peak ◽

Weak Beam ◽

Partial Dislocations ◽

Deviation Parameter ◽

Beam Diffraction

The main features of weak beam images of dislocations were first described by Cockayne et al. using calculations of intensity profiles based on the kinematical and two beam dynamical theories. The feature of weak beam images which is of particular interest in this investigation is that intensity profiles exhibit a sharp peak located at a position very close to the position of the dislocation in the crystal. This property of weak beam images of dislocations has an important application in the determination of stacking fault energy of crystals. This can easily be done since the separation of the partial dislocations bounding a stacking fault ribbon can be measured with high precision, assuming of course that the weak beam relationship between the positions of the image and the dislocation is valid. In order to carry out measurements such as these in practice the specimen must be tilted to "good" weak beam diffraction conditions, which implies utilizing high values of the deviation parameter Sg.

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Digital differential hysteresis iimage processing displays what the microscope acquires but the eye can't see

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139585 ◽

1995 ◽

Vol 53 ◽

pp. 642-643

Author(s):

Klaus-Ruediger Peters

Keyword(s):

Image Processing ◽

Visual System ◽

High Precision ◽

Image Data ◽

Processing Technology ◽

Output Data ◽

Contrast Resolution ◽

Pixel Intensity ◽

Data Reading ◽

Hysteresis Properties

Differential hysteresis processing is a new image processing technology that provides a tool for the display of image data information at any level of differential contrast resolution. This includes the maximum contrast resolution of the acquisition system which may be 1,000-times higher than that of the visual system (16 bit versus 6 bit). All microscopes acquire high precision contrasts at a level of <0.01-25% of the acquisition range in 16-bit - 8-bit data, but these contrasts are mostly invisible or only partially visible even in conventionally enhanced images. The processing principle of the differential hysteresis tool is based on hysteresis properties of intensity variations within an image.Differential hysteresis image processing moves a cursor of selected intensity range (hysteresis range) along lines through the image data reading each successive pixel intensity. The midpoint of the cursor provides the output data. If the intensity value of the following pixel falls outside of the actual cursor endpoint values, then the cursor follows the data either with its top or with its bottom, but if the pixels' intensity value falls within the cursor range, then the cursor maintains its intensity value.

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