Means to improve light source productivity: from proof of concept to field implementation

AbstractA scheme of photoabsorption spectroscopy based on scanning tunneling microscopy (STM) has been developed by using a supercontinuum light as the wideband light source of a Fourier transform interferometer for spectroscopic measurements. The performance was demonstrated for a sample of GaAs. The proof-of-concept test showed that the use of the supercontinuum light instead of halogen lamps greatly enhances the signal-to-noise ratio due to the high brilliance of the supercontinuum light emitted from a small core of the photonic crystal fiber that enables tight focusing of the spectroscopy light onto the sample beneath the STM tip.

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An Eye Tracking based Aircraft Helmet Mounted Display Aiming System

10.36227/techrxiv.18093233.v1 ◽

2022 ◽

Author(s):

Mengtang Li ◽

Quanlong Qiu ◽

Jie Zhu ◽

Chao Gou

Keyword(s):

Eye Tracking ◽

Light Source ◽

Head Movement ◽

Design Methodology ◽

Proof Of Concept ◽

Experimental Characterization ◽

Detailed Design ◽

Working Principle

<p>In this paper, we comprehensively present new advancements towards the working-principle, algorithm, prototype setup and experimental characterization and feasibility demonstration of a new aircraft helmet mounted display aiming system. More specifically, we describe detailed design methodology and algorithm of an eye tracking based HMD aiming system. We also present a proof-of-concept prototype and conduct experiment tests in lab environment to characterize the performance of the proposed system. Lastly, through a comparison with related works, we demonstrate the advantages of the proposed HMD system for free head movement and no additional light source required.</p>

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Muscope: A miniature on-chip lensless microscope

10.1101/2021.06.09.447680 ◽

2021 ◽

Author(s):

Ekta Prajapati ◽

Saurav Kumar ◽

Shishir Kumar

Keyword(s):

Light Source ◽

Super Resolution ◽

Field Of View ◽

Computational Techniques ◽

Wide Field ◽

Proof Of Concept ◽

The Past ◽

Illumination System ◽

Wide Field Of View ◽

On Chip

In the past few decades, a significant amount of effort has been put into developing different lensless microscope designs. The existing lensless microscopes are capable of offering high resolution and wide field-of-view using super-resolution and computational techniques. But, the employment of macroscopic illumination system and unscalable opto-mechanical components limit their cost-effectiveness, scalability, mass production and on-chip integration. In this work, we report Muscope, an on-chip microscope, which fixes these issues. It extends a few mm in each dimension and comprises of an off-the-shelf electronic assembly. The futuristic microLED display chip is utilised as the light source. Each microLED on the chip functions as a microscopic light source whose position and rightness can be electronically controlled. To demonstrate Muscope, we imaged human blood smear and microbeads of diameter upto 1 um. We also provide a proof-of-concept of its suitability with super-resolution and field-of-view enhancement techniques, without additional hardware compulsions.

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An Eye Tracking based Aircraft Helmet Mounted Display Aiming System

10.36227/techrxiv.18093233 ◽

2022 ◽

Author(s):

Mengtang Li ◽

Quanlong Qiu ◽

Jie Zhu ◽

Chao Gou

Keyword(s):

Eye Tracking ◽

Light Source ◽

Head Movement ◽

Design Methodology ◽

Proof Of Concept ◽

Experimental Characterization ◽

Detailed Design ◽

Working Principle

<p>In this paper, we comprehensively present new advancements towards the working-principle, algorithm, prototype setup and experimental characterization and feasibility demonstration of a new aircraft helmet mounted display aiming system. More specifically, we describe detailed design methodology and algorithm of an eye tracking based HMD aiming system. We also present a proof-of-concept prototype and conduct experiment tests in lab environment to characterize the performance of the proposed system. Lastly, through a comparison with related works, we demonstrate the advantages of the proposed HMD system for free head movement and no additional light source required.</p>

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Update VertiGo – light affection of mobile VNG

Current Directions in Biomedical Engineering ◽

10.1515/cdbme-2021-1030 ◽

2021 ◽

Vol 7 (1) ◽

pp. 140-144

Author(s):

Sophia Reinhardt ◽

Joshua Schmidt ◽

Michael Leuschel ◽

Christiane Schüle ◽

Jörg Schipper

Keyword(s):

Computer Vision ◽

Light Source ◽

Clinical Application ◽

The Self ◽

History Taking ◽

Proof Of Concept ◽

Vestibular Nystagmus ◽

Lighting Conditions ◽

Recorded Data ◽

External Light Source

Abstract Dizziness is one of the most frequent symptoms in outpatient practices. For the differentiation of peripheral or central pathogenesis of vertigo, history taking and clinical examination with the detection of nystagmus is elementary. The aim of this study was to investigate the effect of lighting for the detection of horizontal vestibular nystagmus while utilizing a conventional webcam. In the proof-of-concept study, caloric induced vestibular nystagmus was recorded with a conventional video-nystagmography and mobile webcam in addition to an external light source. The analysis of recorded data was performed with a self-developed software using computer vision techniques. The self-designed algorithm detected the existence of nystagmus and its direction in several cases. The experimental webcam-based vestibular nystagmography could be enhanced by improving lighting conditions. Currently, a clinical application for this technique is not approved. Further software improvements are necessary to increase its accuracy.

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A Method for Setting the Clearance Angle

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095200 ◽

1972 ◽

Vol 30 ◽

pp. 388-389

Author(s):

Michael T. Bucek ◽

Howard J. Arnott

Keyword(s):

Experimental Evidence ◽

Light Source ◽

Black Spot ◽

Critical Factor ◽

Clearance Angle ◽

Crude Approximation ◽

Ultrathin Sections

It is believed by the authors, with supporting experimental evidence, that as little as 0.5°, or less, knife clearance angle may be a critical factor in obtaining optimum quality ultrathin sections. The degree increments located on the knife holder provides the investigator with only a crude approximation of the angle at which the holder is set. With the increments displayed on the holder one cannot set the clearance angle precisely and reproducibly. The ability to routinely set this angle precisely and without difficulty would obviously be of great assistance to the operator. A device has been contrived to aid the investigator in precisely setting the clearance angle. This device is relatively simple and is easily constructed. It consists of a light source and an optically flat, front surfaced mirror with a minute black spot in the center. The mirror is affixed to the knife by placing it permanently on top of the knife holder.

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Direct measurement of electron-diffraction-pattern intensities using an energy loss spectrometer

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155311 ◽

1989 ◽

Vol 47 ◽

pp. 668-669

Author(s):

A. G. Jackson ◽

M. Rowe

Keyword(s):

Thermal Effects ◽

Dynamic Range ◽

Scattering Amplitude ◽

Dynamical Theory ◽

Site Symmetry ◽

Proof Of Concept ◽

Parallel Acquisition ◽

Kinematic Approximation ◽

Speed Up ◽

Structure Calculations

Diffraction intensities from intermetallic compounds are, in the kinematic approximation, proportional to the scattering amplitude from the element doing the scattering. More detailed calculations have shown that site symmetry and occupation by various atom species also affects the intensity in a diffracted beam. [1] Hence, by measuring the intensities of beams, or their ratios, the occupancy can be estimated. Measurement of the intensity values also allows structure calculations to be made to determine the spatial distribution of the potentials doing the scattering. Thermal effects are also present as a background contribution. Inelastic effects such as loss or absorption/excitation complicate the intensity behavior, and dynamical theory is required to estimate the intensity value.The dynamic range of currents in diffracted beams can be 104or 105:1. Hence, detection of such information requires a means for collecting the intensity over a signal-to-noise range beyond that obtainable with a single film plate, which has a S/N of about 103:1. Although such a collection system is not available currently, a simple system consisting of instrumentation on an existing STEM can be used as a proof of concept which has a S/N of about 255:1, limited by the 8 bit pixel attributes used in the electronics. Use of 24 bit pixel attributes would easily allowthe desired noise range to be attained in the processing instrumentation. The S/N of the scintillator used by the photoelectron sensor is about 106 to 1, well beyond the S/N goal. The trade-off that must be made is the time for acquiring the signal, since the pattern can be obtained in seconds using film plates, compared to 10 to 20 minutes for a pattern to be acquired using the digital scan. Parallel acquisition would, of course, speed up this process immensely.

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A confocal laser scanning microscope for fluorescence and reflection at video rates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152641 ◽

1989 ◽

Vol 47 ◽

pp. 134-135

Author(s):

P.M. Houpt ◽

A. Draaijer

Keyword(s):

Light Source ◽

Laser Scanning ◽

Focal Point ◽

Confocal Laser Scanning Microscope ◽

Confocal Laser ◽

Point Light Source ◽

Volume Of Interest ◽

Ion Laser ◽

Point Light ◽

Point Detector

In confocal microscopy, the object is scanned by the coinciding focal points (confocal) of a point light source and a point detector both focused on a certain plane in the object. Only light coming from the focal point is detected and, even more important, out-of-focus light is rejected.This makes it possible to slice up optically the ‘volume of interest’ in the object by moving it axially while scanning the focused point light source (X-Y) laterally. The successive confocal sections can be stored in a computer and used to reconstruct the object in a 3D image display.The instrument described is able to scan the object laterally with an Ar ion laser (488 nm) at video rates. The image of one confocal section of an object can be displayed within 40 milliseconds (1000 х 1000 pixels). The time to record the total information within the ‘volume of interest’ normally depends on the number of slices needed to cover it, but rarely exceeds a few seconds.

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Inter-Method Reliability of Pulse Volume Related Measures Derived Using Finger-Photoplethysmography

Journal of Psychophysiology ◽

10.1027/0269-8803/a000197 ◽

2018 ◽

Vol 32 (4) ◽

pp. 182-190 ◽

Cited By ~ 4

Author(s):

Kenta Matsumura ◽

Koichi Shimizu ◽

Peter Rolfe ◽

Masanori Kakimoto ◽

Takehiro Yamakoshi

Keyword(s):

Light Intensity ◽

Adverse Effects ◽

Light Source ◽

Direct Current ◽

Resting State ◽

Current Component ◽

Psychophysiological Measures ◽

Pulse Volume ◽

Optical Paths ◽

Sensor Positions

Abstract. Pulse volume (PV) and its related measures, such as modified normalized pulse volume (mNPV), direct-current component (DC), and pulse rate (PR), derived from the finger-photoplethysmogram (FPPG), are useful psychophysiological measures. Although considerable uncertainties exist in finger-photoplethysmography, little is known about the extent of the adverse effects on the measures. In this study, we therefore examined the inter-method reliability of each index across sensor positions and light intensities, which are major disturbance factors of FPPG. From the tips of the index fingers of 12 participants in a resting state, three simultaneous FPPGs having overlapping optical paths were recorded, with their light intensity being changed in three steps. The analysis revealed that the minimum values of three coefficients of Cronbach’s α for ln PV, ln mNPV, ln DC, and PR across positions were .948, .850, .922, and 1.000, respectively, and that those across intensities were .774, .985, .485, and .998, respectively. These findings suggest that ln mNPV and PR can be used for psychophysiological studies irrespective of minor differences in sensor attachment positions and light source intensity, whereas and ln DC can also be used for such studies but under the condition of light intensity being fixed.

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