scholarly journals Non-contact detection of oxygen saturation based on visible light imaging device using ambient light

2013 ◽  
Vol 21 (15) ◽  
pp. 17464 ◽  
Author(s):  
Lingqin Kong ◽  
Yuejin Zhao ◽  
Liquan Dong ◽  
Yiyun Jian ◽  
Xiaoli Jin ◽  
...  
Keyword(s):  
Visible Light ◽  
Oxygen Saturation ◽  
Contact Detection ◽  
Ambient Light ◽  
Imaging Device ◽  
Visible Light Imaging

An approach to ensure joint illumination & communication performance of a forward error corrected indoor visible light communication (VLC) system in presence of ambient light interference

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Sourish Chatterjee ◽  
Biswanath Roy
Keyword(s):  
Visible Light ◽  
Bit Error Rate ◽  
Error Rate ◽  
Light Emitting Diode ◽  
Visible Light Communication ◽  
Ambient Light ◽  
Ambient Illumination ◽  
Communication Performance ◽  
Light Interference ◽  
Forward Error

AbstractIn recent time of looming radio frequency (RF) spectrum crisis, visible light communication using lighting infrastructure emerged as a potential alternative at an indoor environment. This paper addresses the setback associated with ambient light interference in an indoor Visible Light Communication (VLC) system to ensure joint communication and illumination performance inside an office room. A novel VLC architecture with suitable white light emitting diode (WLED) luminaire arrangement is presented to minimize the dispersion of signal to interference plus noise ratio (SINR) across the room. Luminaires are categorized in two groups viz. data transmitting illuminants and illuminants for lighting purpose. The first group is dedicated to transmit data as well as serves the purpose of illumination. The other set creates only ambient illumination to achieve quality lighting attributes. The proposed forward error corrected receiver configuration discards the ambient light noise originated by the illuminants that serve the ambient illumination. Tail biting convolutional encoder and viterbi decoder are used at the encoding section of the transmitter and decoding section of the receiver respectively to improve bit error rate. Results obtained through MATLAB simulation shows better average bit error rate (BER) in the order of 10−8 measured at uniformly distributed 25 grid points over the working plane. At the same time achieved average horizontal illuminance with good uniformity comply with ISO recommendation.

Spatio-temporal measurement of beam properties in the PLS diagnostic beamline

1998 ◽  
Vol 5 (3) ◽  
pp. 642-644 ◽  
Author(s):  
J. Y. Huang ◽  
I. S. Ko
Keyword(s):  
Visible Light ◽  
Imaging System ◽  
Ccd Camera ◽  
Photon Beam ◽  
Transverse Beam ◽  
Beam Position ◽  
X Ray ◽  
X Ray Imaging ◽  
Visible Light Imaging ◽  
Temporal Measurement

A diagnostic beamline is being constructed in the PLS storage ring for measurement of electron- and photon-beam properties. It consists of two 1:1 imaging systems: a visible-light imaging system and a soft X-ray imaging system. In the visible-light imaging system, the transverse beam size and beam position are measured with various detectors: a CCD camera, two photodiode arrays and a photon-beam position monitor. Longitudinal bunch structure is also investigated with a fast photodiode detector and a picosecond streak camera. On the other hand, the soft X-ray imaging system is under construction to measure beam sizes with negligible diffraction-limited error. The X-ray image optics consist of a flat cooled mirror and two spherical focusing mirrors.

Identification of Pigments in Paint Cross Sections by Reflection Visible Light Imaging Microspectroscopy

2003 ◽  
Vol 75 (4) ◽  
pp. 716-722 ◽  
Author(s):  
Jaap van der Weerd ◽  
Marieke K. van Veen ◽  
Ron M. A. Heeren ◽  
Jaap J. Boon
Keyword(s):  
Visible Light ◽  
Cross Sections ◽  
Visible Light Imaging

Three Dimensional X-Ray Computed Tomography in Materials Science

MRS Bulletin ◽  
1988 ◽  
Vol 13 (1) ◽  
pp. 13-18 ◽  
Author(s):  
J.H. Kinney ◽  
Q.C. Johnson ◽  
U. Bonse ◽  
M.C. Nichols ◽  
R.A. Saroyan ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Sample Preparation ◽  
Visible Light ◽  
Three Dimensional ◽  
Materials Characterization ◽  
Imaging Technology ◽  
X Ray ◽  
X Ray Imaging ◽  
Visible Light Imaging

Imaging is the cornerstone of materials characterization. Until the middle of the present century, visible light imaging provided much of the information about materials. Though visible light imaging still plays an extremely important role in characterization, relatively low spatial resolution and lack of chemical sensitivity and specificity limit its usefulness.The discovery of x-rays and electrons led to a major advance in imaging technology. X-ray diffraction and electron microscopy allowed us to characterize the atomic structure of materials. Many materials vital to our high technology economy and defense owe their existence to the understanding of materials structure brought about with these high-resolution methods.Electron microscopy is an essential tool for materials characterization. Unfortunately, electron imaging is always destructive due to the sample preparation that must be done prior to imaging. Furthermore, electron microscopy only provides information about the surface of a sample. Three dimensional information, of great interest in characterizing many new materials, can be obtained only by time consuming sectioning of an object.The development of intense synchrotron light sources in addition to the improvements in solid state imaging technology is revolutionizing materials characterization. High resolution x-ray imaging is a potentially valuable tool for materials characterization. The large depth of x-ray penetration, as well as the sensitivity of absorption crosssections to atomic chemistry, allows x-ray imaging to characterize the chemistry of internal structures in macroscopic objects with little sample preparation. X-ray imaging complements other imaging modalities, such as electron microscopy, in that it can be performed nondestructively on metals and insulators alike.

Smartphone Positioning Using an Ambient Light Sensor and Reflected Visible Light

2021 ◽  
Author(s):  
Kojiro Abe ◽  
Takuto Sato ◽  
Hiroki Watanabe ◽  
Hiromichi Hashizume ◽  
Masanori Sugimoto
Keyword(s):  
Visible Light ◽  
Ambient Light ◽  
Light Sensor

Infrared laser induced hard damage to visible light imaging system

2010 ◽  
Vol 22 (9) ◽  
pp. 2023-2026 ◽  
Author(s):  
马金龙 Ma Jinlong ◽  
刘长安 Liu Chang’an ◽  
裘伟 Qiu Wei ◽  
常星璋 Chang Xingzhang ◽  
毛静锋 Mao Jingfeng ◽  
...  
Keyword(s):  
Visible Light ◽  
Imaging System ◽  
Infrared Laser ◽  
Visible Light Imaging

scholarly journals Passive Visible Light Detection of Humans

Sensors ◽  
2020 ◽  
Vol 20 (7) ◽  
pp. 1902 ◽  
Author(s):  
Kenneth Deprez ◽  
Sander Bastiaens ◽  
Luc Martens ◽  
Wout Joseph ◽  
David Plets
Keyword(s):  
Visible Light ◽  
Detection Rate ◽  
Detection System ◽  
Light Emitting Diode ◽  
Line Of Sight ◽  
Controlled Environment ◽  
Ambient Light ◽  
Light Emitting ◽  
Light Sensing ◽  
Reflected Light

This paper experimentally investigates passive human visible light sensing (VLS). A passive VLS system is tested consisting of one light emitting diode (LED) and one photodiode-based receiver, both ceiling-mounted. There is no line of sight between the LED and the receiver, so only reflected light can be considered. The influence of a human is investigated based on the received signal strength (RSS) values of the reflections of ambient light at the photodiode. Depending on the situation, this influence can reach up to ± 50 % . The experimental results show the influence of three various clothing colors, four different walking directions and four different layouts. Based on the obtained results, a human pass-by detection system is proposed and tested. The system achieves a detection rate of 100% in a controlled environment for 21 experiments. For a realistic corridor experiment, the system keeps its detection rate of 100% for 19 experiments.

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