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Journal articles on the topic 'Optical instruments'

Author: Grafiati

Published: 4 June 2021

Last updated: 29 July 2024

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1

Abdullahakimovich, Turakhanov Akrom. "Optical Instruments Used In Shooting." American Journal of Applied Sciences 03, no. 03 (March 31, 2021): 68–73. http://dx.doi.org/10.37547/tajas/volume03issue03-11.

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This article gives a brief overview of optical devices used in shooting. This article is intended to acquaint students (students) of higher, secondary special and secondary education institutions with information about optical devices used in shooting.

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Pradana, Pramudya Wahyu, Febriani Febriani, M. Ibnusaputra, and Jumadi Jumadi. "Development of Physics Test Instrument to Measure Verbal Representation of High School Student on Optical Instrument Topic." Jurnal Penelitian Pendidikan IPA 9, no. 10 (October 25, 2023): 7963–68. http://dx.doi.org/10.29303/jppipa.v9i10.3775.

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In the context of Physics learning, verbal representation is very important to foster problem solving skills. However, the role of these representations has not been thoroughly measured and supported by good measurement instruments. In addition, the topic of optical instruments has concepts that can be expressed with verbal representations and is one of the important topics in physics. Therefore, in this study, an instrument was developed to measure students' verbal representation ability on optical instrument topic. The objectives of this research are to (1) determine the instrument's construction and (2) find out the feasibility of the instrument. The instrument was developed following the modified Wilson, Oriondo, and Antonio procedure through three stages: design, testing, and test preparation. The test was piloted on 88 randomly selected students who had studied optical instrument topic. The analysis carried out in this development includes content validity, item-model fit, reliability, and item difficulty level analysis. The development was successful in providing feasible test instrument items for evaluating students' verbal representation of optical instrument topic. This instrument is expected to be used to capture information about students' verbal representation ability, which will then be analyzed to produce more appropriate physics learning instructions.

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3

Okamura, Sadanori. "Optical instruments for JNLT." Astrophysics and Space Science 160, no. 1-2 (1989): 297–311. http://dx.doi.org/10.1007/bf00642785.

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4

Parks, Robert E. "Optics and optical instruments." Optics News 12, no. 11 (November 1, 1986): 28. http://dx.doi.org/10.1364/on.12.11.000028.

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5

Iwan, Wilfred D., Michael A. Moser, and Chia-Yen Peng. "Some observations on strong-motion earthquake measurement using a digital accelerograph." Bulletin of the Seismological Society of America 75, no. 5 (October 1, 1985): 1225–46. http://dx.doi.org/10.1785/bssa0750051225.

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Abstract This paper presents results of a study of some of the characteristics of a PDR-1 digital strong-motion accelerograph. Results are presented for laboratory tests of the background noise level of the instrument, and these results are compared with previously reported observations for optical instruments. Noise levels for the digital instrument are found to be one or two orders of magnitude lower than for an analog optimal instrument. The paper discusses determination of displacement from acceleration data, and results of laboratory tests are presented. An instrument anomaly in the FBA-13 transducer is identified, a simple data correction algorithm proposed, and examples given. The paper also presents detailed results of a comparison of earthquake records obtained from side-by-side digital and optical analog instruments during an aftershock of the 1983 Coalinga earthquake.

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Husna, Hanna Nurul, Siti Mita Rofi’atun Zawjiyah, and Chita Widia. "Implementation QR-Code for Introducing Optical Instruments." Jurnal Penelitian Pendidikan IPA 9, no. 10 (October 25, 2023): 7916–23. http://dx.doi.org/10.29303/jppipa.v9i10.3821.

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The laboratory is one of the important facilities and supports the implementation of learning in tertiary institutions. However, in carrying out practicum activities, students are often constrained by information regarding names, functions, and steps for using instruments. Therefore, the need for information about laboratory equipment is quite important for students. This study aims to produce a website based on a QR code to provide information about the instrument to users and the steps to use it. This research uses research and development methods with the ADDIE model (Analysis, Design, Develop, Implementation, and Evaluation). The questionnaire is used to measure user responses regarding the QR code and its application. Based on the analysis of the problems found, the QR code was successfully created. This QR code was validated by media experts and instrument content experts and obtained valid results. Users show a positive response regarding the use of the QR code for introducing of Refraction Laboratory instruments. Thus, a website-based QR code can be used to provide optical instrument information to users. However, socialization about its use is very necessary for laboratory users.

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7

Pustovoit, V. I., and V. E. Pozhar. "Acoustically-controlled Spectral Optical Instruments." Physics Procedia 70 (2015): 783–86. http://dx.doi.org/10.1016/j.phpro.2015.08.267.

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8

Prodi, V., F. Belosi, S. Agostini, and G. Bettazzi. "Aerodynamic Calibration of Optical Instruments." Applied Occupational and Environmental Hygiene 8, no. 4 (April 1993): 356–59. http://dx.doi.org/10.1080/1047322x.1993.10389220.

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9

Hernandez, G. "Transient response of optical instruments." Applied Optics 24, no. 7 (April 1, 1985): 928. http://dx.doi.org/10.1364/ao.24.000928.

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10

Heacox, William D., and Pierre Connes. "Optical fibers in astronomical instruments." Astronomy and Astrophysics Review 3, no. 3-4 (1992): 169–99. http://dx.doi.org/10.1007/bf00872526.

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11

Siska, Juraj J., Charles R. Hurburgh, and Peter P. Siska. "The Impact of Instrument Engineering Parameters on Spectral Reproducibility across Filter Instruments." Journal of Near Infrared Spectroscopy 9, no. 2 (March 2001): 97–105. http://dx.doi.org/10.1255/jnirs.296.

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This paper explores the role of instrument engineering parameters in master–slave optical differences. Engineering parameters with significant ( p = 0.05) impact were classified into three groups according to the magnitude of their influence (analysis of variance mean squares) on optical differences. The only parameter with high influence was preamplifier gain. Filter area, filter bandwidth, detector temperature, idle filter wheel temperature, sample temperature and optics unit differences exerted medium impact. There were seven properties with low but still significant impact. Software was developed to aid users and manufacturers in selecting optical standardisation and in diagnosing instrument differences.

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12

Williams, Ravaughn, Barbara A. Fink, P. Ewen King-Smith, and G. Lynn Mitchell. "Central Corneal Thickness Measurements: Using an Ultrasonic Instrument and 4 Optical Instruments." Cornea 30, no. 11 (November 2011): 1238–43. http://dx.doi.org/10.1097/ico.0b013e3182152051.

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13

Vasilyev, Roman, Maksim Artamonov, Aleksandr Beletsky, Olga Zorkaltseva, Evgeniya Komarova, Irina Medvedeva, Aleksandr Mikhalev, et al. "Scientific goals of optical instruments of the National Heliogeophysical Complex." Solar-Terrestrial Physics 6, no. 2 (June 27, 2020): 84–97. http://dx.doi.org/10.12737/stp-62202008.

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Studies of the upper atmosphere have to be performed using optical photometric and spectrometric means. Modern devices allow precise photometry of the glow of the night atmosphere — airglow — with high temporal spatial and spectral resolution. As a result, the obtained airglow parameters make it possible to determine the physicochemical properties of the upper atmosphere and observe their variation under the influence of various factors. The National Heliogeophysical Complex, which is being created in Eastern Siberia, is therefore to include a certain set of modern optical instruments. The paper presents the main phenomena that will be investigated by the optical instruments of the complex, provides information on their composition and scientific goals, presents the results of preliminary studies performed using a prototype of the instruments. As a result of the studies, the presence of a significant (about 10 m/sec) vertical wind at various altitudes (100 and 250 km) was established, the importance of taking into account the vertical wind to study the vertical dynamics of the charged component was demonstrated. The long-term dynamics of the vertical wind at an altitude of about 100 km has a pronounced seasonal variations and the absence of diurnal variations, whereas the dynamics of the vertical wind at an altitude of 250 km has a pronounced diurnal variations, which is mostly clearly defined in winter. This suggests the presumed presence of vertical circulation cells at various altitude levels. The possibilities of optical stereoscopy and differential image analysis methods are demonstrated, as applied to the study of fast luminous formations and conducting active ground and space experiments to modify Earth's ionosphere. We report the results of the determination of a three-dimensional picture of a long-lived meteor track with the use of two wide-angle cameras. We propose an algorithm that allows us to get a stereo image of events occurring in the upper atmosphere, recorded simultaneously from different observation points. The joint work of the tools of this complex and the development of cooperation with third-party organizations are shown to be a good enough direction for further study of the vertical dynamics of Earth’s upper atmosphere and space weather phenomena.

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Zhang, Jie, Joseph P. Marto, and James J. Schwab. "Exploring the applicability and limitations of selected optical scattering instruments for PM mass measurement." Atmospheric Measurement Techniques 11, no. 5 (May 22, 2018): 2995–3005. http://dx.doi.org/10.5194/amt-11-2995-2018.

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Abstract. Two optical scattering instruments for particle mass measurement, the Thermo Personal Data RAM (PDR-1500) and the TSI Environmental DustTrak DRX (Model 8543) were evaluated by (1) using poly- and mono-disperse test aerosol in the laboratory, and (2) sampling ambient aerosol. The responses of these optical scattering instruments to different particle characteristics (size, composition, concentration) were compared with responses from reference instruments. A Mie scattering calculation was used to explain the dependence of the optical instruments' response to aerosol size and composition. Concurrently, the detection efficiency of one Alphasense Optical Particle Counter (OPC-N2) was evaluated in the laboratory as well. The relationship between aerosol mass concentration and optical scattering was determined to be strongly dependent on aerosol size and to a lesser extent on aerosol composition (as reflected in the refractive indices of the materials tested) based on ambient measurements. This confirms that there is no simple way to use optical scattering instruments over a wide range of conditions without adjustments based on knowledge of aerosol size and composition. In particular, a test period measuring ambient aerosol with optical scattering instruments and a mass based method (an Aerodyne Aerosol Mass Spectrometer) determined that roughly two thirds of the variance (R2 = 0.64) of the optical to mass signal ratio is explained by the aerosol mass median diameter alone. These observations and calculations help evaluate the applicability and limitations of these optical scattering instruments, and provide guidance to designing suitable applications for each instrument by considering aerosol sources and aerosol size.

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15

Tyc, Tomáš, and Aaron Danner. "Frequency spectra of absolute optical instruments." New Journal of Physics 14, no. 8 (August 29, 2012): 085023. http://dx.doi.org/10.1088/1367-2630/14/8/085023.

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16

Smith, G., K. C. Tan, and M. Letts. "Binocular optical instruments and binocular vision." Clinical and Experimental Optometry 69, no. 4 (June 1986): 137–44. http://dx.doi.org/10.1111/j.1444-0938.1986.tb04577.x.

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17

Leonhardt, Ulf. "Quantum physics of simple optical instruments." Reports on Progress in Physics 66, no. 7 (June 25, 2003): 1207–49. http://dx.doi.org/10.1088/0034-4885/66/7/203.

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18

Raasch, Thomas. "The Eye and Visual Optical Instruments." Optometry and Vision Science 75, no. 6 (June 1998): 380. http://dx.doi.org/10.1097/00006324-199806000-00018.

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19

Tyc, Tomáš, and Ulf Leonhardt. "Transmutation of singularities in optical instruments." New Journal of Physics 10, no. 11 (November 27, 2008): 115038. http://dx.doi.org/10.1088/1367-2630/10/11/115038.

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20

Karabegov, M. A. "Metrological support for optical analytic instruments." Measurement Techniques 28, no. 2 (February 1985): 148–50. http://dx.doi.org/10.1007/bf00862404.

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21

Triebel, Peter, Tobias Moeller, Torsten Diehl, Matthias Burkhardt, Lars Erdmann, and Alexandre Gatto. "Optical Diffraction Gratings for Spectroscopic Instruments." Optik & Photonik 11, no. 2 (April 2016): 41–44. http://dx.doi.org/10.1002/opph.201600010.

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22

Wildgruber, Christoph U., Shuo Qian, Serena H. Chen, Kenneth W. Herwig, Volker S. Urban, and Hugh O'Neill. "A science-driven approach to optimize the design for a biological small-angle neutron scattering instrument." Journal of Applied Crystallography 57, no. 3 (May 31, 2024): 818–30. http://dx.doi.org/10.1107/s1600576724004254.

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Biological small-angle neutron scattering (SANS) instruments facilitate critical analysis of the structure and dynamics of complex biological systems. However, with the growth of experimental demands and the advances in optical systems design, a new neutron optical concept is necessary to overcome the limitations of current instruments. This work presents an approach to include experimental objectives (i.e. the science to be supported by a specific neutron scattering instrument) in the optimization of the neutron optical concept. The approach for a proposed SANS instrument at the Second Target Station of the Spallation Neutron Source at Oak Ridge National Laboratory, USA, is presented here. The instrument is simulated with the McStas software package. The optimization process is driven by an evolutionary algorithm using McStas output data, which are processed to calculate an objective function designed to quantify the expected performance of the simulated neutron optical configuration for the intended purpose. Each McStas simulation covers the complete instrument, from source to detector, including realistic sample scattering functions. This approach effectively navigates a high-dimensional parameter space that is otherwise intractable; it allows the design of next-generation SANS instruments to address specific scientific cases and has the potential to increase instrument performance compared with traditional design approaches.

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23

Fountoulakis, Ilias, Alberto Redondas, Kaisa Lakkala, Alberto Berjon, Alkiviadis F. Bais, Lionel Doppler, Uwe Feister, et al. "Temperature dependence of the Brewer global UV measurements." Atmospheric Measurement Techniques 10, no. 11 (November 22, 2017): 4491–505. http://dx.doi.org/10.5194/amt-10-4491-2017.

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Abstract. Spectral measurements of global UV irradiance recorded by Brewer spectrophotometers can be significantly affected by instrument-specific optical and mechanical features. Thus, proper corrections are needed in order to reduce the associated uncertainties to within acceptable levels. The present study aims to contribute to the reduction of uncertainties originating from changes in the Brewer internal temperature, which affect the performance of the optical and electronic parts, and subsequently the response of the instrument. Until now, measurements of the irradiance from various types of lamps at different temperatures have been used to characterize the instruments' temperature dependence. The use of 50 W lamps was found to induce errors in the characterization due to changes in the transmissivity of the Teflon diffuser as it warms up by the heat of the lamp. In contrast, the use of 200 or 1000 W lamps is considered more appropriate because they are positioned at longer distances from the diffuser so that warming is negligible. Temperature gradients inside the instrument can cause mechanical stresses which can affect the instrument's optical characteristics. Therefore, during the temperature-dependence characterization procedure warming or cooling must be slow enough to minimize these effects. In this study, results of the temperature characterization of eight different Brewer spectrophotometers operating in Greece, Finland, Germany and Spain are presented. It was found that the instruments' response changes differently in different temperature regions due to different responses of the diffusers' transmittance. The temperature correction factors derived for the Brewer spectrophotometers operating at Thessaloniki, Greece, and Sodankylä, Finland, were evaluated and were found to remove the temperature dependence of the instruments' sensitivity.

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24

Yang, Lixiao, Kunyong Lyu, and Chengli Song. "Application of an Optical Tracking System for Motor Skill Assessment in Laparoscopic Surgery." Computational and Mathematical Methods in Medicine 2022 (July 22, 2022): 1–6. http://dx.doi.org/10.1155/2022/2332628.

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Objective. Motion analysis of surgical instruments can be used to evaluate laparoscopic surgical skills, and this study assessed the validity of an optical tracking system for the assessment of laparoscopic surgical motor skills. Methods. Ten experienced surgeons and ten novices were recruited to complete the transferring tasks on a laparoscopic simulator. An optical tracking system, Micron Tracker, was used to capture the marker points on each instrument and to obtain the coordinates of the marker points and the corresponding instrument tip coordinates. The data are processed to create a coordinate system based on the laparoscopic simulator and to calculate the movement parameters of the instruments, such as operating time, path length, speed, acceleration, and smoothness. At the same time, the range of motion of the instrument (insertion depth and pivoting angle) is also calculated. Results. The position that the tip of the instrument can reach is a small, irregularly shaped spatial area. Significant differences ( p < 0.05 ) were found between the surgeon and novice groups in parameters such as operating time, path length, mean speed, mean acceleration, and mean smoothness. The range of insertion depth of the instruments was approximately 150 mm to 240 mm, and the pivoting angles of the left and right instruments were 30.9° and 46.6° up and down and 28.0° and 35.0° left and right, respectively. Conclusions. The optical tracking system was effective in subjectively evaluating laparoscopic surgical skills, with significant differences between the surgeon and novice groups in terms of movement parameters, but not in terms of range of motion.

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Wunch, D., J. R. Taylor, D. Fu, P. Bernath, J. R. Drummond, C. Midwinter, K. Strong, and K. A. Walker. "Simultaneous ground-based observations of O<sub>3</sub>, HCl, N<sub>2</sub>O, and CH<sub>4</sub> over Toronto, Canada by three Fourier transform spectrometers with different resolutions." Atmospheric Chemistry and Physics Discussions 6, no. 5 (October 26, 2006): 10883–928. http://dx.doi.org/10.5194/acpd-6-10883-2006.

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Abstract. An intercomparison of three Fourier transform spectrometers (FTSs) with significantly different resolutions is presented. The highest-resolution instrument has a maximum optical path difference of 250 cm, and the two lower-resolution instruments have maximum optical path differences of 50 cm and 25 cm. The results indicate that the two lower-resolution instruments can retrieve total column amounts of O3, HCl, N2O and CH4 using the SFIT2 retrieval code with percent differences from the high-resolution instrument generally better than 3%, with respect to the high-resolution FTS. Total column amounts of the stratospheric species (O3 and HCl) have larger differences than those of the tropospheric species (N2O and CH4). Instrument line shape (ILS) information is found to be of critical importance when retrieving total columns of stratospheric gases from the lower-resolution instruments. Including the ILS information in the retrievals significantly reduces the difference in total column amounts between the three instruments. The remaining errors for stratospheric species total column amounts can be attributed to the lower sensitivity of the lower-resolution FTSs to the stratosphere.

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Wunch, D., J. R. Taylor, D. Fu, P. Bernath, J. R. Drummond, C. Midwinter, K. Strong, and K. A. Walker. "Simultaneous ground-based observations of O<sub>3</sub>, HCl, N<sub>2</sub>O, and CH<sub>4</sub> over Toronto, Canada by three Fourier transform spectrometers with different resolutions." Atmospheric Chemistry and Physics 7, no. 5 (February 22, 2007): 1275–92. http://dx.doi.org/10.5194/acp-7-1275-2007.

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Abstract. An intercomparison of three Fourier transform spectrometers (FTSs) with significantly different resolutions is presented. The highest-resolution instrument has a maximum optical path difference of 250 cm, and the two lower-resolution instruments have maximum optical path differences of 50 cm and 25 cm. The results indicate that the two lower-resolution instruments can retrieve total column amounts of O3, HCl, N2O and CH4 using the SFIT2 retrieval code with percent differences from the high-resolution instrument generally better than 4%. Total column amounts of the stratospheric species (O3 and HCl) have larger differences than those of the tropospheric species (N2O and CH4). Instrument line shape (ILS) information is found to be of critical importance when retrieving total columns of stratospheric gases from the lower-resolution instruments. Including the ILS information in the retrievals significantly reduces the difference in total column amounts between the three instruments. The remaining errors for stratospheric species total column amounts can be attributed to the lower sensitivity of the lower-resolution FTSs to the stratosphere.

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27

Mínguez-Martínez, Alberto, Piera Maresca, Jesús Caja, and Jesús de Vicente y. Oliva. "Results of a Surface Roughness Comparison between Stylus Instruments and Confocal Microscopes." Materials 15, no. 16 (August 10, 2022): 5495. http://dx.doi.org/10.3390/ma15165495.

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This article presents the results of an LMM-R-2019 interlaboratory comparison. Such comparisons of different families of measuring instruments are one of the activities conducted among the calibration laboratories to maintain their ISO 17025 accreditation. Given that the study of surface roughness is becoming increasingly important in the field of dimensional metrology, the comparison focused on determining the Ra parameter on a pseudorandom metallic roughness standard using two types of measuring instruments: physical contact (stylus instruments) and optical (confocal microscopes). Among the aspects studied was whether the roughness measurements obtained using calibrated confocal microscopes could be compared with those using traditional methods since optical instruments obtain measurements more quickly and responsively than do stylus instruments. The results showed that roughness measurements using confocal microscopes are comparable with those from a traditional stylus instrument.

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TACHIKAWA, Yoshihiko. "Packaging Technologies of Optical Circuits. Optics on Optical Measuring Instruments." Journal of Japan Institute for Interconnecting and Packaging Electronic Circuits 10, no. 5 (1995): 341–45. http://dx.doi.org/10.5104/jiep1995.10.341.

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29

Eriksen, E., and H. N. Hansen. "Surface topography of machined fibre reinforced plastics obtained by stylus instruments and optical profilometers." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 212, no. 6 (June 1, 1998): 479–88. http://dx.doi.org/10.1243/0954405981515789.

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In the manufacturing industry it is important to be able to specify and control the surface quality of the components produced. This is often done with stylus profilometers, by which standardized roughness parameters are found. In recent years instruments based on laser autofocusing have been introduced. They use another working principle to obtain the same parameters, but the settings of most of the measuring variables are not standardized. The present study has investigated aspects that have to be taken into account when the roughness of short fibre reinforced thermoplastics is measured by stylus instruments and by optical profilometers. The measurements were performed on machined surfaces with three distinct different roughness levels. The materials were two thermoplastics, polyoxymethylene and polypropylene, reinforced with short glass fibres. The two stylus instruments gave almost identical values, whereas significantly higher roughnesses were measured with one of the two optical instruments. The optical instruments were identical but with different settings of the control parameters, which resulted in large deviations between the values measured. Some of the differences between the two types of instrument are supposed to relate to the different properties of the fibres and the matrix, whereas others seem to relate to the instruments.

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30

Šošić, Antonela, Ivan Šalinović, Valentina Brzović Rajić, Ana Ivanišević Malčić, Silvana Jukić Krmek, and Ivana Miletić. "Assessment of damage of Endodontic Instruments with Naked Eye and Optical Instruments." Acta Stomatologica Croatica 55, no. 2 (June 15, 2021): 129–36. http://dx.doi.org/10.15644/asc55/2/2.

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31

Kanaya, Y., Y. Komazaki, P. Pochanart, Y. Liu, H. Akimoto, J. Gao, T. Wang, and Z. Wang. "Mass concentrations of black carbon measured by four instruments in the middle of Central East China in June 2006." Atmospheric Chemistry and Physics Discussions 8, no. 4 (August 5, 2008): 14957–90. http://dx.doi.org/10.5194/acpd-8-14957-2008.

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Abstract. Mass concentrations of black carbon (BC) were determined in June 2006 at the top of Mount Tai (36.26° N, 117.11° E, 1534 m a.s.l.), located in the middle of Central East China, using four different instruments: a multi-angle absorption photometer (5012 MAAP, Thermo), a particle soot absorption photometer (PSAP, Radiance Research), an ECOC semi-continuous analyzer (Sunset Laboratory) and an Aethalometer (AE-21, Magee Scientific). High correlation coefficients (R2>0.88) were obtained between the measurements of the BC mass concentrations by the different instruments. From the range of the slopes of the linear least-square fittings, we concluded that the BC concentrations regionally-representative of the area were measured in a range with a maximum-to-minimum ratio of 1.5 (an exception was that the BC (PM2.5) concentrations derived from MAAP were ~2 times higher than the optical measurements (PM2.5) derived from the ECOC analyzer). This range is significant, but is still sufficiently narrow to better constrain the large and highly uncertain emission rate of BC from China. In detail, two optical instruments (the MAAP instrument and the PSAP instrument equipped with a heated inlet (400°C)) tended to give higher concentrations than the thermal EC concentrations observed by the ECOC analyzer. The ratios of optical BC to thermal EC showed a positive correlation with the OC/EC ratio reported by the ECOC analyzer, suggesting two possibilities. One is that the optical instruments overestimated BC concentrations in spite of careful cancellation of the scattering effect in the MAAP instrument and the expected evaporation of volatile species by heating the inlet of the PSAP instrument. The other is that the determined split points between OC and EC were too late when a large amount of OC underwent charring during the analysis, resulting in an underestimation of EC by the ECOC analyzer. High ratios of optical BC to thermal EC were recorded when the NOx/NOy ratio was low, implying the coating of the particles became thicker in the aged air mass and resulted in the optical instruments overestimating BC concentrations owing to the lensing effect.

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32

Gordon, Howard R., and Kuiyuan Ding. "Self-shading of in-water optical instruments." Limnology and Oceanography 37, no. 3 (May 1992): 491–500. http://dx.doi.org/10.4319/lo.1992.37.3.0491.

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33

Boppart, S. A., B. E. Bouma, C. Pitris, G. J. Tearney, J. G. Fujimoto, and M. E. Brezinski. "Forward-imaging instruments for optical coherence tomography." Optics Letters 22, no. 21 (November 1, 1997): 1618. http://dx.doi.org/10.1364/ol.22.001618.

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34

Sidequersky, Fernanda Vincia, Laura Verzé, Andrea Mapelli, Guglielmo Amedeo Ramieri, and Chiarella Sforza. "Quantification of Facial Movements by Optical Instruments." Journal of Craniofacial Surgery 25, no. 1 (January 2014): e65-e70. http://dx.doi.org/10.1097/scs.0000000000000379.

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35

Picciotto, Joanna. "Optical Instruments and the Eighteenth-Century Observer." Studies in Eighteenth Century Culture 29, no. 1 (2000): 123–53. http://dx.doi.org/10.1353/sec.2010.0183.

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36

Perczel, Janos, Carlos Garcia-Meca, and Ulf Leonhardt. "Partial transmutation of singularities in optical instruments." Journal of Optics 13, no. 7 (June 30, 2011): 075103. http://dx.doi.org/10.1088/2040-8978/13/7/075103.

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37

Warren, J., K. Strohbehn, S. Murchie, D. Fort, E. Reynolds, G. Heyler, K. Peacock, et al. "Selected configuration tradeoffs of contour optical instruments." Acta Astronautica 52, no. 2-6 (January 2003): 111–16. http://dx.doi.org/10.1016/s0094-5765(02)00145-5.

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38

Sirohi, Rajpal. "Resolving power of optical instruments: A Tutorial." Asian Journal of Physics 30, no. 1 (January 1, 2021): 31–43. http://dx.doi.org/10.54955/ajp.30.1.2021.31-43.

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39

Purata Sifuentes, Omar Jair. "Indirect Determination of the Internal Diameter of Glass Conical Volumetric Instruments." Entreciencias: Diálogos en la Sociedad del Conocimiento 11, no. 25 (October 20, 2023): 1–13. http://dx.doi.org/10.22201/enesl.20078064e.2023.25.85557.

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Purpose: To determine the values of the internal diameter in conical-shaped glass volumetric instruments using height measurements, without needing to measure the wall thickness of the volumetric container, which will allow calculating the contribution to the uncertainty of volume measurement due to the adjustment of the meniscus. Methodological design: The proposed method approximates volume by a series of truncated cones bounded by instrument graduation lines. The series of truncated cones thus defined is subject to comply with a geometric restriction. Then, for the graduation lines of the volumetric instrument that did not adhere to the constraint, a power regression model allows approximation of the value of the internal diameter. Results: The proposed approach could be used as an alternative method to determine the internal diameter of glass conical volumetric instruments in cases where using a vernier caliper or optical comparator is not an option, either because the geometry of the conical instrument does not allow it or because higher cost instruments are not available. Research limitations: Only two types of conical volumetric instruments were tested: an Imhoff cone and a centrifuge tube, with scopes of 1 L and 100 mL, respectively, from only two commercial brands of laboratory glassware. The volume of the tip of the instrument was modeled up to the first graduation mark, always as a semi-ellipsoid of revolution. Findings: Comparing the direct measurement of the internal diameter of the volumetric instruments with an optical comparator, there is an average relative error below 10 %, with a maximum value below 20 % for the two different conical glass instruments studied.

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Dahneke, Barton, and Bradley Johnson. "A Method for Cross Calibrating Particle Counters." Journal of the IEST 29, no. 5 (September 1, 1986): 31–36. http://dx.doi.org/10.17764/jiet.1.29.5.41529jm555633304.

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A system for generating participate air contamination standards of known size distribution and concentration was developed and used to determine the accuracy of several optical particle counters (OPCs) for the measurement of paniculate air contamination. Of particular concern was the substantial instrument-to-instrument variability of up to a factor of six or more sometimes observed when measuring the same sample with two similar instruments. We found that while the agreement between two instruments calibrated from the manufacturer's calibration data was sometimes poor, the same instruments calibrated by our methods agreed within 10% in their measured results. We therefore recommend use of these new calibration methods when precise air contamination measurements or interchangeability of instruments are needed.

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Stack, Robert F., Carol J. Bayles, Anne-Marie Girard, Karen Martin, Cynthia Opansky, Katherine Schulz, and Richard W. Cole. "Quality Assurance Testing for Modern Optical Imaging Systems." Microscopy and Microanalysis 17, no. 4 (April 11, 2011): 598–606. http://dx.doi.org/10.1017/s1431927611000237.

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AbstractThe days of being able to ascertain instrument performance by simply peering through the eye pieces at a specimen are gone. However, users and granting agencies need to be confident that data collected on these instruments is uniform and quantifiable both over time and between instruments. Ideally, a LASER should not fluctuate, illumination should be completely uniform, and colors should be perfectly aligned. To check the current performance of imaging equipment, we conducted a worldwide research study utilizing three image-based tests: long-/short-term illumination stability, co-registration of signals across various wavelengths, and field illumination uniformity. To differentiate between “acceptable” and “unacceptable” performance, the deviation in illumination power could not exceed 10% (long term) or 3% (short term), the difference in the center-of-mass of imaged multicolored beads could not exceed >1 pixel between different wavelengths, and field illumination values could not exceed 10% (horizontal) or 20% (diagonal) deviation. This study established the current state of microscope performance through simple, efficient, and robust tests, while defining relative standards to assist cores in maintaining their instruments in optimal operating conditions. We developed cross-platform performance standards that will improve the validity of quantitative measurements made using various light microscopes.

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Viviana Vlăduţescu, Daniela, Stephen E. Schwartz, and Dong Huang. "Optical instruments synergy in determination of optical depth of thin clouds." EPJ Web of Conferences 176 (2018): 08008. http://dx.doi.org/10.1051/epjconf/201817608008.

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Optically thin clouds have a strong radiative effect and need to be represented accurately in climate models. Cloud optical depth of thin clouds was retrieved using high resolution digital photography, lidar, and a radiative transfer model. The Doppler Lidar was operated at 1.5 μm, minimizing return from Rayleigh scattering, emphasizing return from aerosols and clouds. This approach examined cloud structure on scales 3 to 5 orders of magnitude finer than satellite products, opening new avenues for examination of cloud structure and evolution.

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Strojnik, Marija, Beethoven Bravo-Medina, Robert Martin, and Yaujen Wang. "Ensquared Energy and Optical Centroid Efficiency in Optical Sensors: Part 1, Theory." Photonics 10, no. 3 (February 28, 2023): 254. http://dx.doi.org/10.3390/photonics10030254.

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High-performance megapixel focal plane arrays with small pixels have been widely used in modern optical remote sensing, astronomical, and surveillance instruments. In the prediction models applied in the traditional instrument performance analysis, the image of a point source is assumed to fall on the center of a detector pixel. A geometrical image of a point source in the realistic optical system may actually fall on any position on the detector pixel because the sensor’s line of sight includes pointing errors and jitter. This traditional assumption may lead to an optimistic error, estimated at between 10% and 20%. We present the critical factors that impact the performance estimate in a realistic instrument design based on the prediction for the noise-equivalent power (NEP). They are the optical centroid efficiency (OCE) and the ensquared energy, or more precisely, the energy on the rectangular detector pixel (EOD). We performed the simulation studies for imaging with an optical system with and without a generalized rectangular central obscuration.

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Tanré, D., F. M. Bréon, J. L. Deuzé, O. Dubovik, F. Ducos, P. François, P. Goloub, M. Herman, A. Lifermann, and F. Waquet. "Remote sensing of aerosols by using polarized, directional and spectral measurements within the A-Train: the PARASOL mission." Atmospheric Measurement Techniques 4, no. 7 (July 12, 2011): 1383–95. http://dx.doi.org/10.5194/amt-4-1383-2011.

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Abstract. Instruments dedicated to aerosol monitoring are recently available and the POLDER (POLarization and Directionality of the Earth's Reflectances) instrument on board the PARASOL (Polarization & Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) mission is one of them. By measuring the spectral, angular and polarization properties of the radiance at the top of the atmosphere, in coordination with the other A-Train instruments, PARASOL provides the aerosol optical depths (AOD) as well as several optical and microphysical aerosol properties. The instrument, the inversion schemes and the list of aerosol parameters are described. Examples of retrieved aerosol parameters are provided as well as innovative approaches and further inversion techniques.

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Gosain, Sanjay, John Harvey, Valentin Martinez Pillet, Frank Hill, and Thomas N. Woods. "A Compact Full-disk Solar Magnetograph Based on Miniaturization of the GONG Instrument*." Publications of the Astronomical Society of the Pacific 135, no. 1046 (April 1, 2023): 045001. http://dx.doi.org/10.1088/1538-3873/acca49.

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Abstract The design of compact instruments is crucial for the scientific exploration by smaller spacecraft such as CubeSats and deep space missions, as these missions require minimal instrument mass. In this proof-of-concept study, we demonstrate the miniaturization of the Global Oscillation Network Group (GONG) instrument. GONG instruments routinely produce full-disk maps of the Sun’s photosphere using the Ni i 676 nm absorption line, measuring Doppler shifts and magnetic fields. To miniaturize the GONG optical design, we propose replacing the bulky Lyot filter with a narrow-band interference filter. We validate this concept through numerical modeling and proof-of-concept observations. Finally, we propose a simple optical design for building a compact version of GONG.

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Lee, Wai Tung, Joel Hagman, Damian Martin Rodriguez, Annika Stellhorn, Alex Backs, Thomas Arnold, Elizabeth Blackburn, et al. "Polarisation Development at the European Spallation Source." EPJ Web of Conferences 286 (2023): 03004. http://dx.doi.org/10.1051/epjconf/202328603004.

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To meet the ever-increasing user demand, eleven of the fifteen European Spallation Source (ESS) instruments under construction aim to offer polarised neutrons for user experiments. They include an imaging instrument, a SANS instruments, two reflectometers, three diffractometers, and four spectrometers. In conjunction with in-kind contributions and instrumentation grants, the ESS Polarisation Project will support the incorporation of polarisation analysis on eight of the eleven instruments. The project aims to deliver polarised neutrons for first-science experiments as instruments enter operation. Different polariser and polarisation analyser techniques will be available to accommodate the specifics of experiments on a given instrument. Polarised 3He neutron spin filter using either Metastable Optical Pumping (MEOP) or Spin-Exchange Optical Pumping (SEOP) techniques will provide shared-use equipment among many instruments, with SEOP’s main application being in situ beam-polarisation. Several instruments will also use polarising-supermirror devices. To provide wide-bandwidth spin-flipping capability to the time-of-flight instruments, Adiabatic Fast Passage (AFP) neutron spin flippers, also known as gradient-field radiofrequency spin flippers will be the main method of choice. Devices based on the same AFP principle will also be used to flip 3He nuclear spins. We are constructing our first 3He polariser setup, including field coils to produce highly uniform magnetic field. Monte Carlo simulations are being done for the supermirror polarisers. To ensure science-focused development, we are working with university partners in doing scientific experiments with polarised neutrons. These are some of the activities developing polarisation analysis for ESS instruments in our project.

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te Plate, Maurice, Brian O’Sullivan, Pierre Ferruit, David Lee, Martyn Wells, Jess Koehler, Markus Melf, and Wolfgang Holota. "The European optical contribution to the James Webb Space Telescope." Advanced Optical Technologies 7, no. 6 (December 19, 2018): 353–64. http://dx.doi.org/10.1515/aot-2018-0041.

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Abstract The James Webb Space Telescope (JWST) is frequently referred to as the follow-on mission to the Hubble Space Telescope (HST). The ‘Webb’ will be the biggest space telescope ever built and is expected to enable astounding new science. The observatory comprises a 6.5-m-diameter telescope with a segmented primary mirror and four high-performance optical science instruments. The JWST has mostly been optimized to work in the near- (0.6–5.0 μm) and mid-infrared (5.0–29 μm) wavelength regions. The project is a strong international partnership led by the National Aeronautics and Space Administration (NASA) with contributions from the European Space Agency (ESA) and the Canadian Space Agency (CSA). The observatory is currently scheduled for launch in early 2021 from Kourou, French Guyana, by an ESA-provided Ariane 5 rocket. This paper will focus on the European optical contribution to the mission, which mainly consists of two highly advanced optical science instruments: The multi-object near-infrared spectrograph (NIRSpec) and the mid-infrared instrument (MIRI). The opto-mechanical design considerations and the realization of both instruments will be described, and we will conclude with a short JWST project status report and future outlook.

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Davis, John. "Commission 9: Instruments and Techniques (Instruments et Techniques)." Transactions of the International Astronomical Union 21, no. 1 (1991): 41–52. http://dx.doi.org/10.1017/s0251107x00009780.

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The period covered by this report has seen significant progress in the development of the new generation of telescopes with apertures in the 8 m plus range. The period has encompassed the major construction phase of the 10 m Keck Telescope, witnessed the commissioning of the European Southern Observatory’s (ESO) New Technology Telescope and the approval of funding for the ESO Very Large Telescope (VLT). Significant progress has been achieved in developing the necessary technology for manufacturing and figuring large mirrors. There have been major expansions of activity in the areas of active control of telescope optics and adaptive optics, and in high angular resolution interferometry with several new groups entering both fields. The use of optical fibers, particularly in the area of multiple-object spectroscopy, has continued to grow. Several telescopes can now be operated remotely and the control systems of new telescopes are being designed to facilitate remote operation.

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Zhang, Shi Lin. "Research on Optical Radiation Measuring System Based on Virtual Instrument." Applied Mechanics and Materials 484-485 (January 2014): 337–42. http://dx.doi.org/10.4028/www.scientific.net/amm.484-485.337.

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Using virtual instrument technology, digital signal processing technology and traditional optical radiation measuring technology to construct optical radiation measuring system breaks the construction methods of traditional instruments. Signal processing, collection, control and process of measuring system are implemented by the software LabVIEW8.2. And they are integrated in a computer. The computer not only is data processing center, but also is instrument control center. While measuring, the user uses the mouse to operate the handles including knobs, switch and buttons of virtual instrument panel to select instrument functions and set various parameters, which realizes measuring optical radiation with different wave bands and different intensity. And the user can change instrument operation panel, modify system software, transform instrument function, and customize instrument parameters, which embodies the idea that the software is the instrument.

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Tuno, Nedim, and Dušan Kogoj. "First Optical Theodolites." Geodetski glasnik, no. 41 (December 31, 2011): 42–51. http://dx.doi.org/10.58817/2233-1786.2011.45.41.42.

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The article gives an overview of the first optical theodolites, which marked a major milestone in the development and use of surveying instruments. Their appearance is connected to the name of the famous constructor Heinrich Wild and had a immeasurably positive impact on the entire industry of surveying instruments, that is still felt today. The purpose of the article is not commercial in terms of advertising of certain technical solutions of the manufacturer Wild (Leica), but an attempt to show the measurement technology that has dominated the previous century, through the lens of legendary T2 theodolite.

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