Physical domain data compression in high-speed optical measurement systems (Conference Presentation)

AbstractOptical measurement systems are an important part of the portfolio of 3D topography sensors. By precise, contactless and rapid measurements these sensors constitute an alternative to tactile instruments. In this contribution the principle of a laser interferometric distance sensor is presented, which in combination with lateral scan axes acts as a topography sensor and also as distance sensor for the compensation of vibrations in a coherence scanning Linnik interferometer. An advantage of this distance sensor is its high acquisition rate of height values, which in case of working as a topography sensor enables high scan velocities as it is demonstrated at a chirp standard measured with a scan velocity of 80 mm/s. This is much higher than the scan velocity of tactile instruments, which are typically limited up to 1 mm/s. In addition, the compensation of vibration disturbances demonstrates the capability of the fast distance measurement.In contrast to other existing high-speed point sensors the relevant components are mass products. This keeps the costs of the sensor setup in a limited range. Furthermore, the sensor shows potential of much higher measurement rates than 116 kHz provided by the sensor used here.

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Nano-imprinted subwavelength gratings as polarizing beamsplitters

Journal of the European Optical Society Rapid Publications ◽

10.1186/s41476-021-00149-8 ◽

2021 ◽

Vol 17 (1) ◽

Author(s):

Julian Wüster ◽

Yannick Bourgin ◽

Patrick Feßer ◽

Arne Behrens ◽

Stefan Sinzinger

Keyword(s):

Nanoimprint Lithography ◽

Optical Measurement ◽

Design Method ◽

Optical Systems ◽

Surface Metrology ◽

Measurement Systems ◽

Common Path ◽

Dielectric Coatings ◽

Subwavelength Gratings ◽

Wide Range

AbstractPolarizing beamsplitters have numerous applications in optical systems, such as systems for freeform surface metrology. They are classically manufactured from birefringent materials or with stacks of dielectric coatings. We present a binary subwavelength-structured form-birefringent diffraction grating, which acts as a polarizing beamsplitter for a wide range of incidence angles −30∘…+30∘. We refine the general design method for such hybrid gratings. We furthermore demonstrate the manufacturing steps with Soft-UV-Nanoimprint-Lithography, as well as the experimental verification, that the structure reliably acts as a polarizing beamsplitter. The experimental results show a contrast in efficiency for TE- and TM-polarization of up to 1:18 in the first order, and 34:1 in the zeroth order. The grating potentially enables us to realize integrated compact optical measurement systems, such as common-path interferometers.

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Detection of foot contact in treadmill running with inertial and optical measurement systems

Journal of Biomechanics ◽

10.1016/j.jbiomech.2021.110419 ◽

2021 ◽

pp. 110419

Author(s):

Jasper Reenalda ◽

Marit A. Zandbergen ◽

Jelle D. Harbers ◽

Max R. Paquette ◽

Clare E. Milner

Keyword(s):

Optical Measurement ◽

Treadmill Running ◽

Measurement Systems

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Methods of temperature measurement in microwave heating technologies

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2021-6-20-28 ◽

2021 ◽

pp. 20-28

Author(s):

Boris A. Lapshinov

Keyword(s):

Temperature Measurement ◽

Microwave Heating ◽

Microwave Radiation ◽

Electromagnetic Fields ◽

Optical Measurement ◽

Measurement Methods ◽

Heating Systems ◽

Measurement Systems ◽

Processed Material ◽

Spectral Pyrometry

In industrial technological processes associated with the heating of the processed material by microwave radiation, it is necessary to measure the temperatures of objects. Methods for measuring temperatures in the fields of technology using microwave heating systems are considered. The main possibilities, disadvantages and limitations of the used contact and non-contact (optical) measurement methods are determined. The requirements for temperature measurement systems under conditions of exposure to strong electromagnetic fields are listed. The possibilities of the spectral pyrometry method are especially noted.

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Multi-layered tissue head phantoms for noninvasive optical diagnostics

Journal of Innovative Optical Health Sciences ◽

10.1142/s1793545815410059 ◽

2015 ◽

Vol 08 (03) ◽

pp. 1541005 ◽

Cited By ~ 39

Author(s):

M. S. Wróbel ◽

A. P. Popov ◽

A. V. Bykov ◽

M. Kinnunen ◽

M. Jędrzejewska-Szczerska ◽

...

Keyword(s):

Optical Properties ◽

Near Infrared ◽

Optical Measurement ◽

Human Head ◽

Medical Diagnostics ◽

Optical Parameters ◽

Measurement Systems ◽

Tissue Phantoms ◽

Optical And Mechanical Properties

Extensive research in the area of optical sensing for medical diagnostics requires development of tissue phantoms with optical properties similar to those of living human tissues. Development and improvement of in vivo optical measurement systems requires the use of stable tissue phantoms with known characteristics, which are mainly used for calibration of such systems and testing their performance over time. Optical and mechanical properties of phantoms depend on their purpose. Nevertheless, they must accurately simulate specific tissues they are supposed to mimic. Many tissues and organs including head possess a multi-layered structure, with specific optical properties of each layer. However, such a structure is not always addressed in the present-day phantoms. In this paper, we focus on the development of a plain-parallel multi-layered phantom with optical properties (reduced scattering coefficient [Formula: see text] and absorption coefficient μa) corresponding to the human head layers, such as skin, skull, and gray and white matter of the brain tissue. The phantom is intended for use in noninvasive diffuse near-infrared spectroscopy (NIRS) of human brain. Optical parameters of the fabricated phantoms are reconstructed using spectrophotometry and inverse adding-doubling calculation method. The results show that polyvinyl chloride-plastisol (PVCP) and zinc oxide ( ZnO ) nanoparticles are suitable materials for fabrication of tissue mimicking phantoms with controlled scattering properties. Good matching was found between optical properties of phantoms and the corresponding values found in the literature.

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Optical measurement systems

Mechatronics ◽

10.1007/978-1-4615-3068-8_4 ◽

1991 ◽

pp. 49-74

Author(s):

D. A. Bradley ◽

D. Dawson ◽

N. C. Burd ◽

A. J. Loader

Keyword(s):

Optical Measurement ◽

Measurement Systems

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GIF IMAGE HARDWARE COMPRESSORS

Information, Computing and Intelligent systems ◽

10.20535/2708-4930.2.2021.244189 ◽

2021 ◽

Author(s):

Ivan Mozghovyi ◽

Anatoliy Sergiyenko ◽

Roman Yershov

Keyword(s):

Data Compression ◽

Data Storage ◽

High Speed ◽

Data Transfer ◽

Future Research ◽

Volume Data ◽

High Speed Data ◽

Lzw Algorithm ◽

And Storage ◽

Speed Data Transmission

Increasing requirements for data transfer and storage is one of the crucial questions now. There are several ways of high-speed data transmission, but they meet limited requirements applied to their narrowly focused specific target. The data compression approach gives the solution to the problems of high-speed transfer and low-volume data storage. This paper is devoted to the compression of GIF images, using a modified LZW algorithm with a tree-based dictionary. It has led to a decrease in lookup time and an increase in the speed of data compression, and in turn, allows developing the method of constructing a hardware compression accelerator during the future research.

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