Share
VIDEOS 1 TO 50
General Characteristics of Photodetectors
General Characteristics of Photodetectors
Published: 2013/10/04
Channel: nptelhrd
Photodetectors
Photodetectors
Published: 2014/09/22
Channel: nptelhrd
Photodetector Basics SAMPLE
Photodetector Basics SAMPLE
Published: 2014/06/21
Channel: Peter Beyersdorf
Photodetector and Its Features. Simple ...
Photodetector and Its Features. Simple ...
Published: 2012/04/30
Channel: ChipDipvideo
Basics of Photodetectors
Basics of Photodetectors
Published: 2016/02/09
Channel: Physics.
QWIP Photodetector
QWIP Photodetector
Published: 2012/08/15
Channel: Cloud .Tube
Photodiode in Hindi
Photodiode in Hindi
Published: 2017/02/10
Channel: Electrical Technology
Photodetector
Photodetector
Published: 2018/01/22
Channel: Electrical and Electronics Engineering
Intel researcher talks about the Avalanche Photodetector
Intel researcher talks about the Avalanche Photodetector
Published: 2008/12/10
Channel: IntelResearchLabs
Photodetector - NoMADA®
Photodetector - NoMADA®
Published: 2015/04/29
Channel: Solace Labs
PHOTODIODE AND PHOTODETECTOR
PHOTODIODE AND PHOTODETECTOR
Published: 2018/05/18
Channel: Thatchaa Girl
13. Fundamentals of Photodetectors
13. Fundamentals of Photodetectors
Published: 2013/02/21
Channel: kashyap B
Photodetector!
Photodetector!
Published: 2015/06/26
Channel: Phan Thuan
Photodiode
Photodiode
Published: 2013/06/15
Channel: Qpage
How to use photo-detector | Digitizing Light and measure in Mach-Zehnder interferometer
How to use photo-detector | Digitizing Light and measure in Mach-Zehnder interferometer
Published: 2016/03/10
Channel: Vijayan T
Photodetector
Photodetector
Published: 2016/12/15
Channel: Free Educational Channel
Infra Red Thermal Imaging Photodetector Basics in HINDI
Infra Red Thermal Imaging Photodetector Basics in HINDI
Published: 2017/07/31
Channel: LearnEveryone
The Photo Detector
The Photo Detector
Published: 2016/04/22
Channel: Verisure UK
Mod-01 Lec-21 Photo Detector
Mod-01 Lec-21 Photo Detector
Published: 2014/03/24
Channel: nptelhrd
Photodetector integrated with EWD device
Photodetector integrated with EWD device
Published: 2015/09/13
Channel: LIJI CHEN
Photodetector
Photodetector
Published: 2016/01/29
Channel: WikiAudio
Balanced photodetector
Balanced photodetector
Published: 2017/06/24
Channel: IH S
Graphene Photodetector   Video1
Graphene Photodetector Video1
Published: 2016/05/05
Channel: Matthew Cieslak
Photodetector
Photodetector
Published: 2009/12/11
Channel: dispensamatic
Photodetector signal check (FBG)
Photodetector signal check (FBG)
Published: 2017/11/21
Channel: Reina Villegas
CCNY How to connect the wire with photodetector
CCNY How to connect the wire with photodetector
Published: 2015/05/13
Channel: Xinbin Xu
semiconductor chapter photodetector
semiconductor chapter photodetector
Published: 2016/11/07
Channel: semiconductor ELE541
Advances in Silicon Photonics: Avalanche Photodetector
Advances in Silicon Photonics: Avalanche Photodetector
Published: 2008/12/10
Channel: IntelResearchLabs
x96 Graphene Photodetector
x96 Graphene Photodetector
Published: 2015/03/15
Channel: Noah Acosta
Avalanche Photodetector project
Avalanche Photodetector project
Published: 2008/12/13
Channel: IntelResearchLabs
The Verisure Photo Detector
The Verisure Photo Detector
Published: 2018/07/15
Channel: Better Price Merchant Solutions
Arduino: IR Photodetector System Test 1
Arduino: IR Photodetector System Test 1
Published: 2016/01/04
Channel: TinselKoala
Photodetector circuit testing
Photodetector circuit testing
Published: 2009/03/26
Channel: Mark Gu
What is Avalanche Photodiode?
What is Avalanche Photodiode?
Published: 2012/06/28
Channel: FOSCO CONNECT
Semiconductor Photo-Diodes
Semiconductor Photo-Diodes
Published: 2013/10/04
Channel: nptelhrd
What Is Meant By Photodetector?
What Is Meant By Photodetector?
Published: 2018/07/15
Channel: SMART Hairstyles
PIN PHOTODIODE
PIN PHOTODIODE
Published: 2015/03/16
Channel: Sukanya Bhattacharjya
How to say "photodetector"! (High Quality Voices)
How to say "photodetector"! (High Quality Voices)
Published: 2017/02/10
Channel: WordBox
Lesson7 Buzzer   photodetector
Lesson7 Buzzer photodetector
Published: 2015/06/11
Channel: urbanoutlaw858
ZnO Nanowires Based Flexible UV Photodetectors for Wearable Dosimetry - IEEE Sensors 2017
ZnO Nanowires Based Flexible UV Photodetectors for Wearable Dosimetry - IEEE Sensors 2017
Published: 2018/02/23
Channel: BEST_UofG
Mod-01 Lec-20 Photo Diodes and Detector Noise
Mod-01 Lec-20 Photo Diodes and Detector Noise
Published: 2014/03/24
Channel: nptelhrd
Photodetectors by Dr  Partha Sarkar
Photodetectors by Dr Partha Sarkar
Published: 2017/08/19
Channel: Dr.Partha Sarkar
Global Voltaic Photo-Detector Market Research Report 2017
Global Voltaic Photo-Detector Market Research Report 2017
Published: 2017/12/26
Channel: Market Research Reports, Inc.
Download Introduction to Light Trapping in Solar Cell and Photo detector Devices Book
Download Introduction to Light Trapping in Solar Cell and Photo detector Devices Book
Published: 2016/08/15
Channel: E. Patriya
What does photodetector mean?
What does photodetector mean?
Published: 2017/10/21
Channel: What Does That Mean?
Introduction to Light Trapping in Solar Cell and Photo detector Devices
Introduction to Light Trapping in Solar Cell and Photo detector Devices
Published: 2017/06/18
Channel: abduloh hardi
Online proton therapy monitoring: clinical test of a Silicon-photodetector-based in-beam PET
Online proton therapy monitoring: clinical test of a Silicon-photodetector-based in-beam PET
Published: 2018/03/06
Channel: ScienceVio
BEAM PHOTO DETECTOR ใช้ Laser ตรวจจับผู้บุกรุก
BEAM PHOTO DETECTOR ใช้ Laser ตรวจจับผู้บุกรุก
Published: 2018/06/13
Channel: นวพล วารินทร์
Quantum Tunneling Photo Detector Array
Quantum Tunneling Photo Detector Array
Published: 2015/04/20
Channel: Red-White-Black-Yellow Man/Woman
Introduction to Light Trapping in Solar Cell and Photo detector Devices
Introduction to Light Trapping in Solar Cell and Photo detector Devices
Published: 2017/03/03
Channel: Abrahamsen
NEXT
GO TO RESULTS [51 .. 100]

WIKIPEDIA ARTICLE

From Wikipedia, the free encyclopedia
  (Redirected from Ambient light sensor)
Jump to navigation Jump to search

A photodetector salvaged from a CD-ROM drive. The photodetector contains three photodiodes, visible in the photo (in center).

Photodetectors, also called photosensors, are sensors of light or other electromagnetic radiation.[1] A photo detector has a p–n junction that converts light photons into current. The absorbed photons make electron–hole pairs in the depletion region. Photodiodes and photo transistors are a few examples of photo detectors. Solar cells convert some of the light energy absorbed into electrical energy.

Types[edit]

A commercial amplified photodetector for use in optics research

Photodetectors may be classified by their mechanism for detection:[2][unreliable source?][3][4]

  • Photoemission or photoelectric effect: Photons cause electrons to transition from the conduction band of a material to free electrons in a vacuum or gas.
  • Thermal: Photons cause electrons to transition to mid-gap states then decay back to lower bands, inducing phonon generation and thus heat.
  • Polarization: Photons induce changes in polarization states of suitable materials, which may lead to change in index of refraction or other polarization effects.
  • Photochemical: Photons induce a chemical change in a material.
  • Weak interaction effects: photons induce secondary effects such as in photon drag[5][6] detectors or gas pressure changes in Golay cells.

Photodetectors may be used in different configurations. Single sensors may detect overall light levels. A 1-D array of photodetectors, as in a spectrophotometer or a Line scanner, may be used to measure the distribution of light along a line. A 2-D array of photodetectors may be used as an image sensor to form images from the pattern of light before it.

A photodetector or array is typically covered by an illumination window, sometimes having an anti-reflective coating.

Properties[edit]

There are a number of performance metrics, also called figures of merit, by which photodetectors are characterized and compared[2][3]

  • Spectral response: The response of a photodetector as a function of photon frequency.
  • Quantum efficiency: The number of carriers (electrons or holes) generated per photon.
  • Responsivity: The output current divided by total light power falling upon the photodetector.
  • Noise-equivalent power: The amount of light power needed to generate a signal comparable in size to the noise of the device.
  • Detectivity: The square root of the detector area divided by the noise equivalent power.
  • Gain: The output current of a photodetector divided by the current directly produced by the photons incident on the detectors, i.e., the built-in current gain.
  • Dark current: The current flowing through a photodetector even in the absence of light.
  • Response time: The time needed for a photodetector to go from 10% to 90% of final output.
  • Noise spectrum: The intrinsic noise voltage or current as a function of frequency. This can be represented in the form of a noise spectral density.
  • Nonlinearity: The RF-output is limited by the nonlinearity of the photodetector[7]

Devices[edit]

Grouped by mechanism, photodetectors include the following devices:

Photoemission or photoelectric[edit]

Semiconductor[edit]

Photovoltaic[edit]

Thermal[edit]

  • Bolometers measure the power of incident electromagnetic radiation via the heating of a material with a temperature-dependent electrical resistance. A microbolometer is a specific type of bolometer used as a detector in a thermal camera.
  • Cryogenic detectors are sufficiently sensitive to measure the energy of single x-ray, visible and infrared photons.[14]
  • Pyroelectric detectors detect photons through the heat they generate and the subsequent voltage generated in pyroelectric materials.
  • Thermopiles detect electromagnetic radiation through heat, then genetating a voltage in thermocouples.
  • Golay cells detect photons by the heat they generate in a gas-filled chamber, causing the gas to expand and deform a flexible membrane whose deflection is measured.

Photochemical[edit]

Polarization[edit]

Graphene/silicon photodetectors[edit]

A graphene/n-type silicon heterojunction has been demonstrated to exhibit strong rectifying behavior and high photoresponsivity. Graphene is coupled with silicon quantum dots (Si QDs) on top of bulk Si to form a hybrid photodetector. Si QDs cause an increase of the built-in potential of the graphene/Si Schottky junction while reducing the optical reflection of the photodetector. Both the electrical and optical contributions of Si QDs enable a superior performance of the photodetector.[16]

Frequency range[edit]

In 2014 a technique for extending semiconductor-based photodetector's frequency range to longer, lower-energy wavelengths. Adding a light source to the device effectively "primed" the detector so that in the presence of long wavelengths, it fired on wavelengths that otherwise lacked the energy to do so.[17]

See also[edit]

References[edit]

  1. ^ Haugan, H. J.; Elhamri, S.; Szmulowicz, F.; Ullrich, B.; Brown, G. J.; Mitchel, W. C. (2008). "Study of residual background carriers in midinfrared InAs/GaSb superlattices for uncooled detector operation". Applied Physics Letters. 92 (7): 071102. Bibcode:2008ApPhL..92g1102H. doi:10.1063/1.2884264. 
  2. ^ a b Donati, S. "Photodetectors" (PDF). unipv.it. Prentice Hall. Retrieved 1 June 2016. 
  3. ^ a b Yotter, R.A.; Wilson, D.M. (June 2003). "A review of photodetectors for sensing light-emitting reporters in biological systems". IEEE Sensors Journal. 3 (3): 288–303. Bibcode:2003ISenJ...3..288Y. doi:10.1109/JSEN.2003.814651. 
  4. ^ Stöckmann, F. (May 1975). "Photodetectors, their performance and their limitations". Applied Physics. 7 (1): 1–5. Bibcode:1975ApPhy...7....1S. doi:10.1007/BF00900511. 
  5. ^ A. Grinberg, Anatoly; Luryi, Serge (1 July 1988). "Theory of the photon-drag effect in a two-dimensional electron gas". Physical Review B. 38 (1): 87–96. Bibcode:1988PhRvB..38...87G. doi:10.1103/PhysRevB.38.87. 
  6. ^ Bishop, P.; Gibson, A.; Kimmitt, M. (October 1973). "The performance of photon-drag detectors at high laser intensities". IEEE Journal of Quantum Electronics. 9 (10): 1007–1011. Bibcode:1973IJQE....9.1007B. doi:10.1109/JQE.1973.1077407. 
  7. ^ Hu, Yue (1 October 2014). "Modeling sources of nonlinearity in a simple pin photodetector". Journal of Lightwave Technology. 32 (20): 3710–3720. Bibcode:2014JLwT...32.3710H. doi:10.1109/JLT.2014.2315740. 
  8. ^ "Photo Detector Circuit". oscience.info. 
  9. ^ Paschotta, Dr. Rüdiger. "Encyclopedia of Laser Physics and Technology - photodetectors, photodiodes, phototransistors, pyroelectric photodetectors, array, powermeter, noise". www.rp-photonics.com. Retrieved 2016-05-31. 
  10. ^ "PDA10A(-EC) Si Amplified Fixed Gain Detector User Manual" (PDF). Thorlabs. Retrieved 24 April 2018. 
  11. ^ "DPD80 760nm Datasheet". Resolved Instruments. Retrieved 24 April 2018. 
  12. ^ Rizzi, M.; D`Aloia, M.; Castagnolo, B. "Semiconductor Detectors and Principles of Radiation-matter Interaction". Journal of Applied Sciences. 10 (23): 3141–3155. Bibcode:2010JApSc..10.3141R. doi:10.3923/jas.2010.3141.3155. 
  13. ^ "Silicon Drift Detectors" (PDF). tools.thermofisher.com. Thermo Scientific. 
  14. ^ Enss, Christian (Editor) (2005). Cryogenic Particle Detection. Springer, Topics in applied physics 99. ISBN 3-540-20113-0. 
  15. ^ Yuan, Hongtao; Liu, Xiaoge; Afshinmanesh, Farzaneh; Li, Wei; Xu, Gang; Sun, Jie; Lian, Biao; Curto, Alberto G.; Ye, Guojun; Hikita, Yasuyuki; Shen, Zhixun; Zhang, Shou-Cheng; Chen, Xianhui; Brongersma, Mark; Hwang, Harold Y.; Cui, Yi (1 June 2015). "Polarization-sensitive broadband photodetector using a black phosphorus vertical p–n junction". Nature Nanotechnology. 10 (8): 707–713. Bibcode:2015NatNa..10..707Y. doi:10.1038/nnano.2015.112. 
  16. ^ Yu, Ting; Wang, Feng; Xu, Yang; Ma, Lingling; Pi, Xiaodong; Yang, Deren (2016). "Graphene Coupled with Silicon Quantum Dots for High-Performance Bulk-Silicon-Based Schottky-Junction Photodetectors". Advanced Materials. doi:10.1002/adma.201506140. 
  17. ^ Claycombe, Ann (2014-04-14). "Research finds "tunable" semiconductors will allow better detectors, solar cells". Rdmag.com. Retrieved 2014-08-24. 

External links[edit]

Disclaimer

None of the audio/visual content is hosted on this site. All media is embedded from other sites such as GoogleVideo, Wikipedia, YouTube etc. Therefore, this site has no control over the copyright issues of the streaming media.

All issues concerning copyright violations should be aimed at the sites hosting the material. This site does not host any of the streaming media and the owner has not uploaded any of the material to the video hosting servers. Anyone can find the same content on Google Video or YouTube by themselves.

The owner of this site cannot know which documentaries are in public domain, which has been uploaded to e.g. YouTube by the owner and which has been uploaded without permission. The copyright owner must contact the source if he wants his material off the Internet completely.

Powered by YouTube
Wikipedia content is licensed under the GFDL and (CC) license