L03 Quantum Optics and Photometry_DMS_2024_StudentNotes.pdf

2/2/24 OPTM 4101 Principles of Optics *TR -zenit Introduction to Quantum Optics and Photometry...

2/2/24 OPTM 4101 Principles of Optics *TR -zenit Introduction to Quantum Optics and Photometry Danuta Sampson, Discipline of Optometry, SAH [email protected] 1 Acknowledgement of country The University of Western Australia acknowledges that its campus is situated on Noongar land, and that Noongar people remain the spiritual and cultural custodians of their land, and continue to practise their values, languages, beliefs and knowledge. Artist: Dr Richard Barry Walley OAM 2 1  2/2/24 Contents ****** Introduction to Quantum Optics Radiometry and Photometry # Black body Spectral sensitivity of the eye **** Fi RELA T ↑74*AHRXTR. Photons and dual nature of light Radiant and luminous power INDEX *** I ↑ ETART2D** 7 EVE Photoelectric effect and quantum Solid angle K theory. Radiant and luminous intensity IEEET ZET , Atomic structure TFEx H discovered by 19005. 5 5 What is light? * a) ah 7*** 4 ↑Tahi. Pi*7(47) ri Particle iR * Ett It Al ↳ 4747 / TY Th A. light red lightt Sodiune > - yellow - - 17 radiation (light) due to 17 emit electromagnetic where objects emit light across a spectrum of Is a process absolute zero above ( their temperature wavelengths. Thermal emission of light characteristics of this light , its a wavelength intensity distribution , depend on the objects temperature. http://howthingswork.org/physics-qm-black-body-radiation/ 18 18 9  2/2/24 in si 6Black body Perfect. emitter Absorbs all incident radiation & The hotter the , body re-emits energy at a spectrum it the more energy of wavelengths determined solely radiates by its temperature according to , Planck's law. It doesn't reflect or transmit radiation. Principle of conservation of energy: A+R+T=100% A – absorption, R – reflection, T – transmission 19 http://www.electrical4u.com/black-body-radiation/ 19 Black body radiation properties: Wien’s law ↓ peak wavelength ↑ temperature , the & the Spectrum shifts to shorter · wavelength Wien’s law- peak wavelength is inversely proportional to temperature of the black body (nm) http://www.electrical4u.com/black-body-radiation/ 20 http://www.giangrandi.ch/optics/blackbody/blackbody.shtml 20 10  2/2/24 Thermal sources !.#$%&$!" ' ) !!"# = (Wien’s displacement law) → For a human temperature = 37oC = Infrared (9340 nm) *' 21 http://www.mnn.com/earth-matters/animals/blogs/hot-and-wild-14-thermal-images-of-animals 21 Tungsten bulb https://pxhere.com/fr/photo/1239560 22 22 11  2/2/24 Summary: Light sources -only emits specific wavelength - discrete spectrum Atomic emission - Generates all wavelength (define by the tempretures) -Continuous Spectrum. Thermal emission https://www.youtube.com/watch?v=NMqIOWWegV8 http://astronomy.nju.edu.cn/~lixd/GA/AT4/AT404/HTML/AT40401.htm 23 http://homepages.uc.edu/~hansonmm/ASTRO/LECTURENOTES/W07/Light/EmissionLineTutorial.html 23 Radiometry and Photometry Now we’ve produced light, how do we measure how much we’ve got? Credit: freepik.com 24 24 12  2/2/24 Radiometry and Photometry RADIOMETRY PHOTOMETRY Quantifies radiation across Quantifies radiation in the the EM spectrum visible portion of the spectrum Employs physical constants Is weighted to the human eye response (considering vision) > - measures physical quantities of order to visible vision EM radiation in Quantifying > -. characterize visible light with physical terms. Reports radiation 25 > - in energy 25 Radiometry and Photometry From light source to our eyes Radiometry measures the radiant energy produced by an electromagnetic source. Fil te r including all wavelength , not just visible light. Modified from Kalloniatis and Luu. http://webvision.med.utah.edu/book/part-viii-gabac-receptors/psychophysics-of-vision/ 26 26 13  measures that specifically human eye. 2/2/24 subset of radiometry the by of light perceived of the human The properties sensitivity & a the whichvariesactos detect into account It takes Visual system , Radiometry and Photometry - From light source to our eyes visible part of the EM only the Fil te Photometry measures the part of the radiant r power that we can perceive (visible) and takes into account that we perceive some λs brighter than other. It is how our eye interacts with the spectrum. Each radiometric magnitude/unit has a corresponding photometric magnitude/unit. Modified from Kalloniatis and Luu. http://webvision.med.utah.edu/book/part-viii-gabac-receptors/psychophysics-of-vision/ 27 27 Photometry and Spectral sensitivity of the eye Photopic O O the illuminate efficiency , The higher to that wavelength. we are sensitive the more it. we perceive the brighter Spectral luminous efficiency function of the human eye Schwartz, Visual Perception 28 28 14  2/2/24 Radiant power and Luminous power measure the total power of electromagnetic radiation emitted , reflected , transmitted Radiant power or flux (ϕE) or received , per unit time. bally Watts=Joules/s , W the amount of the light / the energy. consumes Howbrigh theisum. 29 29 Radiant power and Luminous power Radiant power or flux (ϕE) Watts=Joules/s , W the measure of the perceived power of light the human. eye by Luminous power or flux (ϕV) Lumens (lm) Watts to Lumen: Luminous flux = Radiant flux * Luminous efficiency - https://en.wikipedia.org/wiki/Luminous_flux 30 how well a light 30 produce visible source a light. 15  2/2/24 Solid angle: Steradian (Sr) A steradian can be defined as the solid angle subtended at the center of a unit sphere by a unit area on its surface. https://en.wikipedia.org/wiki/Steradian 31 31 Radiant intensity and Luminous intensity Radiant intensity (IE) A Unit: W/sr r Ω Luminous intensity (IV): Unit: Candela = lm/sr &'()*+', 23'4 &'()*+', )*./*,).0 = 5+3)6 7*83/ 32 32 16 photometry measurement of light :. luminous flux : the measure of power emitted by a light source and is measured in lumens //m) 2/2/24. "The cup is poorly illuminated" "The luminated. poorly or Cup is v by illumination describes light falling onto the cup , whereas luminance is the perceived brightness of light coming off the cup. Radiance and Luminance Radiance (LE) Unit: W/sr/m2 Luminance (LV): Unit: Candela/m2=lux DOES NOT CHANGE WITH DISTANCE MEASURED 33 33 Irradiance/Illuminance Irradiance (EE) Unit: W/m2 Illuminance (Ev) Unit: lux = lm/m2 Luxmeter https://www.udemy.com/using-a-photographic-light-meter/ Schwartz, Visual perception 34 34 17  2/2/24 as the distance off of light falls the intensity Describe how - increases (Inverse square law for illuminance sources from a point The illuminance (lumens falling on a surface) decreases with the square of the distance as the point source is moved away from the surface. The surface is assumed to be normal (perpendicular) to the light source. Schwartz, Visual perception 35 35 36 36 18  2/2/24 Lambert’s Cosine law of illumination Light source not perpendicular to the task surface → illuminance (EV) reduced by cosine of the angle with perpendicular (q) http://oceanoptics.com/faq/response-cosine-corrector/ 37 37 Summary Luminance Flux Luminous intensity Schwartz, Visual perception 38 38 19  measure of the amount of luminous flux(lightl falling on a surface 2/2/24 per unit area - how much light available measuring is to illuminate the area. Summary LIGHT INTENSITY LUMINANCE LUMINOUS FLUX & ILLUMINANCE Photo credit: https://www.erco.com/en/designing-with-light/lighting-knowledge/photometry/radiant-power-7527/ 39 39 Transmittance: Filters Filters that reduce all wavelengths) such as neutral density (ND) filters Filters that remove specific wavelengths (coloured filters) https://en.wikipedia.org/wiki/Neutral-density_filter https://www.vision-doctor.com/en/colour-filters.html 40 40 20  2/2/24 Not all coloured filters work perfectly https://www.edmundoptics.com.au/c/shortpass-edge-filters/733/# 41 41 References and Resources 1. Hecht, E. (2017). Optics. Pearson. 2. Strong, S. (2023). Introduction to visual optics: a light approach. Elsevier. 3. Schwartz, S.H. (2002). Geometrical and visual optics: A clinical introduction. McGraw-Hill Education. 4. Bennett, A.G. and Rabbett, R.B. (2007). Clinical visual optics. Butterworth-Heinemann. 5. Schwartz, S. (2010). Visual Perception: A Clinical Orientation. McGraw Hill Medical Introductory concepts (Ch 2) Electromagnetic spectrum, dual nature of light Chapter 4: Photometry 6. Donnely, J.F. and Massa N.M. (2010). Light: Introduction to optics and photonics. Lulu (chapter 2). 7. For extension: Keating, M.P. (1988). Geometric, physical, and visual optics. Elsevier Health Sciences. Chapter 24: 24.2, 24.3, 24.4, 24.5, 24.6 42 42 21