Physics/Questions Answered by Expert Optics C
| Subject | Date Asked |
| Colors | 10/11/2010 |
| Q: ) I'm an undergrad student confused with the difference between emissivity and law of attenuation ... A: I think what you call the "law of absorption" is the same thing as the Beer-lambert law. This law ... | |
| question | 4/18/2010 |
| Q: iam in the 8th grade from syria. how do electromagnetic waves penetrate our body? thanks alot A: Low frequency waves (radio waves) will pass through your body just as in air. Microwaves are very ... | |
| Second Harmonic Generation | 4/17/2010 |
| Q: I am a college student studying chemistry and I am doing a project that involves lasers. I have some ... A: You pretty much have the right answers. SHG, like many nonlinear effects, is a two-photon effect. ... | |
| Momentum of light | 3/28/2010 |
| Q: I've read somewhere that only red light is used in photography because of its low energy which does ... A: I assume by "photography" you mean photographic development. Yes, light has a small amount of ... | |
| Fiber Optics | 3/23/2010 |
| Q: I do not understand how data can be transferred using fiber optics and light, it is quite puzzling ... A: Data is transferred digitally through fiber optics, much as computer data is transferred digitally ... | |
| Pleochroism | 3/21/2010 |
| Q: I have recently read two conflicting explanations for pleochroism in minerals placed between crossed ... A: I checked the wikepedia entry on this and I see what you mean. I'm sure that both effects contribute ... | |
| energy levels | 3/2/2010 |
| Q: I am 38 years old, have studied subjects like biology, English and history at the university level ... A: Tue, As an engineer more than a physicist, I rely on the laws of thermodynamics first and think ... | |
| Fiber Optics | 3/1/2010 |
| Q: First off it's good to see you on here again. Wasn't sure if you retired from the site. lol. And to ... A: I'm not sure of the exact price, but you should be able to turn up surplus fiber for very cheap. My ... | |
| Light | 2/23/2010 |
| Q: It is said that solving the Maxwell's equations proved that light is electromagnetic radiation. The ... A: There are plenty of other demonstrations that light is a wave, particularly those involving ... | |
| Reversed spectrum | 2/20/2010 |
| Q: Why does the spectrum reverse when you look at the light source through a prism? When the light ... A: My first instinct was to reject your question, but I'll jump in with reservations. First, asking the ... | |
| Glass slab experiment | 2/10/2010 |
| Q: Why a spectrum cannot be received in case of glass slab and only prism ? A: A prism bends light proportional to the refractive index of the glass. The refractive index is ... | |
| Light reflection | 2/9/2010 |
| Q: Since when we view images from space, we are looking at the past, I was wondering if it might be at ... A: Yes, this is certainly possible in theory. In practice, the light from earth spreads our uniformly ... | |
| Light | 1/28/2010 |
| Q: How old is light? From what I understand if some one could travel near to the speed of light they ... A: OK, I get lazy about specifying the speed of light as being in a vacuum. Light does travel slower as ... | |
| Light | 1/26/2010 |
| Q: How old is light? From what I understand if some one could travel near to the speed of light they ... A: There are probably many ways to answer your question, but I can respond with a couple of comments: ... | |
| lens | 1/25/2010 |
| Q: I am trying to make the cheapest, easiest light lens for creating heat. There are 4 ideas here. ... A: I assume you are focusing the sun onto a collector. Upper left is common in this type of ... | |
| Light Refraction | 1/24/2010 |
| Q: Why does looking at an object through a semi-curved dish filled with water equate to the same ... A: The rectangular dish does not alter the angle of the light from before to after the dish, it just ... | |
| Light and Movement | 1/22/2010 |
| Q: It is ok if you do not want to answer this question since it may not directly deal with optics in ... A: I'm not sure what kind of budget you have in mind, or even what your mechanical constraints are. In ... | |
| Waves | 1/21/2010 |
| Q: How do I find the "curved" distance of a wave if I only know the straight peak to peak length ? ... A: This is a math question rather than an optics question. You would have to take the line integral ... | |
| concave mirror | 1/18/2010 |
| Q: sir, My brother asked me one question on concave mirror. In his textbook for the proof that focal ... A: You are describing the "paraxial approximation," which means that we look only at rays close to the ... | |
| Reversed spectrum | 1/17/2010 |
| Q: Why does the spectrum reverse when you look at the light source through a prism? When the light ... A: I tried to think about this one for a while, but the reason is clear when you draw the rays in a ... | |
| Manipulating light | 1/12/2010 |
| Q: Firstly, about me - I have no scientific background, but I do have an interest in general physics. ... A: 1. Other than by interposing physical matter, the only way to bend light is gravity. This effect is ... | |
| the coefficient of friction | 1/6/2010 |
| Q: why can the coefficient of static friction be greater than 1? can please explain the physical ... A: The coefficient of friction is not a normalized property. A value larger than one simply means that ... | |
| Optics-sprectum | 1/1/2010 |
| Q: Is it possible that an atom can radiate frequency of complementary color in hot condition of the ... A: The absorption and emission of an atom at a given frequency is the same. When hot, the atom will ... | |
| optics | 6/28/2008 |
| Q: my question is that why white light has less energy than voilet light usually given answer is that ... A: White light is not an average of all colors, but a superposition of all colors. A superposition does ... | |
| Is 400 nm light high-energy UV? | 6/26/2008 |
| Q: In http://www.allexperts.com/user.cgi?m=6&catID=1358&qID=4691552 you said "400 nm is the upper end ... A: UVA is an ISO standard band including 400 nm light. The color "violet" is completely unregulated, as ... | |
| An oven consisting of 400 nm lasers -- pros and cons? | 6/21/2008 |
| Q: I am thinking of a hypothetical oven for food that has 400 nm lasers only on the top. These lasers ... A: Certainly you are correct in your example. However: 1. Most substances are not identically ... | |
| An oven consisting of 400 nm lasers -- pros and cons? | 6/19/2008 |
| Q: I am thinking of a hypothetical oven for food that has 400 nm lasers only on the top. These lasers ... A: While lasers are well known for high intensity, their total power is very low. In fact, the highest ... | |
| Three Lens System (Thin Lens) | 6/11/2008 |
| Q: I have a basic understanding of optics and good algebra skills. I'm trying to determine the ... A: Kathleen, When you combine two thin lenses, the equations are straightforward and you are probably ... | |
| prism | 5/28/2008 |
| Q: does a hollow prism split white light into its constituent colours? A: Sure, just not very much. Passing light through a hollow prism is effectively the same as passing ... | |
| Optics freeware and software | 5/14/2008 |
| Q: I have an idea for a possible optics-related invention. Are there freeware or software applications ... A: You want a ray-tracing code. There are several of this type available for use in graphics rendering ... | |
| Quantum Gate | 5/13/2008 |
| Q: I am 23 years old. I have a high school diploma. No real real college education to speak of. But I ... A: There have been some rudimentary applications of quantum operations, including entanglement of up to ... | |
| concave lens | 5/8/2008 |
| Q: can in any case a concave form a real image ANSWER: Yes, but only for a virtual object located ... A: I assumed you meant a lens in air. Certainly a concave "lens" of lower refractive index than the ... | |
| fibre optics | 5/3/2008 |
| Q: can't we send more than one light rays passing through the same optic fibre parallely in such a way ... A: Ok, thanks for the useful background information. There is no way to simultaneously transmit ... | |
| fibre optics | 5/2/2008 |
| Q: can't we send more than one light rays passing through the same optic fibre parallely in such a way ... A: Yes. This is called multiplexing, and there are several ways to do it. The best way is wavelength ... | |
| Light and mirrors | 4/29/2008 |
| Q: What would be the effect of having a powerful beam of light caught between two perfectly placed ... A: While building up arbitrarily large fields is theoretically possible, the law of conservation of ... | |
| Light and mirrors | 4/26/2008 |
| Q: What would be the effect of having a powerful beam of light caught between two perfectly placed ... A: The configuration you describe is frequently encountered in optics. It is called an optical cavity ... | |
| Digital Cameras - Optical Equations Apply Equally? | 4/22/2008 |
| Q: How wonderful you are continuing to provide this invaluable service! In 2005 you provided me with ... A: You are welcome. I've had my ups and downs with the service. You should select 'private' in the ... | |
| Electromagnetism | 4/20/2008 |
| Q: I am an amateur physics student and am currently trying to learn the subject with the aim of gaining ... A: As described by Maxwell's equations, the oscillation of electrical charge (i.e., by changing ... | |
| physics | 4/7/2008 |
| Q: Suppose you are given 3 similar transparent glass cubes. Two of the cubes are made of glass A, while ... A: This sounds like a homework question, so I'll give an incomplete answer. You want to figure this ... | |
| Can you SEE black? | 4/3/2008 |
| Q: I am a college student, and i do not study physics or anything, but i am intrigued to find out ... A: Kimberly, I think the key point here is to distinguish between "seeing" and "perceiving." By your ... | |
| Why does certain colors absorb light differently? | 3/6/2008 |
| Q: I am in eighth grade and will try to understand even the most complicated of answers. My question ... A: Andy, I'm not sure exactly how to interpret your question, but I will try. Heat and light are two ... | |
| Is an omnidirectional laser possible to design? | 3/5/2008 |
| Q: Most lasers give out a unidirectional beam of light. Is it possible to design an omnidirectional ... A: I do not think such a thing is possible. Laser light is created by stimulated emission, in which an ... | |
| lasers and photons | 3/4/2008 |
| Q: In the output from a laser, can we describe the length of coherence useful for holography or ... A: There is certainly value in trying to explain interference using quantum theory, especially because ... | |
| Which laser is hotter -- 400 nm or 700 nm? | 3/1/2008 |
| Q: Let's say there are two lasers -- one that is 400 nm and the other 700nm. The only difference ... A: You have defined the total power (wattage) of each laser to be identical. Although blue photons are ... | |
| Spectrum | 2/19/2008 |
| Q: Is there a way to project a rainbow large enough to cover a wall unlike small simple prisms that ... A: James, Certainly. I would use a diffraction grating rather than a prism. By controlling the line ... | |
| Diffused Reflection | 2/18/2008 |
| Q: In my physics course at high-school, i learnt that if the roughness of the surface is less than ... A: I can start an analogy that has absolutely nothing to do with light: if I place a book onto a rough ... | |
| Shadow w/o object? | 2/16/2008 |
| Q: I noticed you are into optics so thought I'd ask a professional so shed some light (sorry) on a ... A: Ken, As you suppose, the object casting the shadow must be either close to the cloud or very large. ... | |
| Black body emissions | 2/14/2008 |
| Q: I came across another answer you provided to somebody asking about why a solar collector cannot ... A: James, Thinking about geometry (collection apertures and magnification) is destracting you from ... | |
| UV light transmittance through water | 2/13/2008 |
| Q: What wavelength range of Ultra Violet light does water transmit (UV-A, UV-B, UV-C)? and How much ... A: My apologies for a late reply. I have not been getting emails from Allexperts and I thought I was ... | |
| Relativity | 2/10/2008 |
| Q: I thought this idea might be of use to someone interested in the speed of light. Situation: Lying ... A: Gregory, It is the basic principle of relativity that the speed of light is absolute, irrelevant of ... | |
| Speed of Light | 1/25/2008 |
| Q: I am so happy that there is someone who states that he wants to hear questions about light. I have ... A: Light is electromagnetic waves. That is, light is an oscillating electric and magnetic field. Light ... | |
| Light | 1/22/2008 |
| Q: Why are clouds white? ANSWER: Scatter from particles much smaller than the wavelength of light has ... A: Arun, My apologies. I have been having trouble lately with targeting my answers to the level of my ... | |
| Caustic curve | 1/20/2008 |
| Q: Please explain what is caustic curve and how is it formed in detail. A: I remember this topic being somewhat confusing when first I had to learn it. This is my best shot: ... | |
| Light | 1/19/2008 |
| Q: Why are clouds white? A: Scatter from particles much smaller than the wavelength of light has a strong spectral dependence. ... | |
| The Universe and the Neuorns | 1/12/2008 |
| Q: I am a researcher looking into science and religion and during my studies I have found out that ... A: In my opinion, our visual and cognitive systems are finely attuned to recognizing patterns, even ... | |
| Electronmicroscope | 1/11/2008 |
| Q: How does an electron microscope turn a wavelength into a black and white image? Where does the ... A: An electron microscope does not use light at all. Rather, a beam of electrons is directed onto the ... | |
| Physics | 1/9/2008 |
| Q: Why does ordinary light gets dispersed whereas laser light doesn't? A: Padma, I saw your comments. Please note that I get questions from school kids, retirees, physics ... | |
| optics | 1/7/2008 |
| Q: sir can you explain me why does sun appear oval and bigger in size during sun set and sun rise. I ... A: John, This seems like a reasonable description of the oval sun: ... | |
| Reflection angle near the speed of light | 12/19/2007 |
| Q: If a mirror reflecting a beam of light at a 45º angle is sped up to 90% the speed of light in the ... A: Yes: To the stationary observer, the mirror will appear to compress along the direction of motion, ... | |
| Street lights | 12/13/2007 |
| Q: I would like to know why all the street and highway lights are given the yellow color and not ... A: These are low-pressure sodium lamps. Because they are very efficient, they are the cheapest option ... | |
| wet clothes | 12/10/2007 |
| Q: i was wondering why is it that when clothes get wet they look darker? A: Sophie, I've been thinking about this one for a day now, and I think I have a good answer. This ... | |
| Why are magnetic field lines always depicted as pointing from north to south? | 11/18/2007 |
| Q: Southern magnetic energy is emitted from the side of a magnet taking in the lines of force. Northern ... A: The analogy between elecrons and "magnetons" is misleading, as there is no such thing as magnetic ... | |
| quantum behaviour of light | 11/17/2007 |
| Q: I am 14 and I am studying in class X (equivalent 'o' level). Can you explain why light reflects or ... A: Waqar, When light travels through a medium, it causes vibrations in atoms and molecules. Because of ... | |
| microscope | 11/9/2007 |
| Q: why the objective lens of microscope has short focal length and not a long one? A: The optics of a microscope are shown here: http://web.uvic.ca/ail/techniques/scope_basics.html The ... | |
| optics | 11/6/2007 |
| Q: How much is the linear absorption coefficient of normal glass for light? A: Your question is too general to give a single answer. There are many types of glass and the ... | |
| Polarization and Holograms | 10/22/2007 |
| Q: I am doing research for a science fair project. I ran across the Idea of polarization researching ... A: Zakyia, Holograms are simply a device for encoding a higher-dimensional information into a ... | |
| Optical Fibres | 10/18/2007 |
| Q: My question is about how long it takes for a ray of light, that is just totally internally ... A: I use the equation for critical angle, theta_cr: sin(theta_cr) = n_cl/n_co n_cl = clad refractive ... | |
| Night phenomena | 10/12/2007 |
| Q: I was wondering if there is anything the eye is blind to during the day that it can see after dark? ... A: The eye is very insensitive to color in low light conditions. Therefore, one could easily make the ... | |
| light/prisms | 10/11/2007 |
| Q: "Clear," light into it's three primary colors (red Yellow blue). My question is this: are the ... A: Pete, White light is nothing more than the superposition of light of many colors (the color of ... | |
| Light | 10/10/2007 |
| Q: Which of the following locations requires the highest illuminance? A. a residential stairway B. a ... A: For legal, design, and other reasons, there are published standards for illumination levels in ... | |
| Light | 10/5/2007 |
| Q: Which of the following locations requires the highest illuminance? A. a residential stairway B. a ... A: You would have to give me some more information to make a decision. Are you talking about standards ... | |
| Galvanized Steel Pipes As Convex Mirrors? | 10/4/2007 |
| Q: An artist has submitted plans showing 10-ft diameter galvanized steel pipes to be laid horizontally, ... A: I think your concern is justified, but the problem is also readily mitigated. There will be strong ... | |
| Prisims | 10/1/2007 |
| Q: When light enters a prism it diffracts into its seven colors because of the different wavelengths of ... A: When light enters a clear material, the angle it bends is given by Snell's law, which you can find ... | |
| Energy of an electromagnetic wave? | 9/10/2007 |
| Q: I am a college student and these days we were taught about EM waves. Now I know that the instant ... A: The true form of the energy is E X B, where E and B are vector electric and magnetic fields and "X" ... | |
| Near/Far Holograms | 8/31/2007 |
| Q: I was wondering if there is a kind of hologram that revolves through images based on your distance ... A: Holograms whose reconstructed image depends on distance do exist, but they are fairly complex. Your ... | |
| INSTRUMENTATION | 8/29/2007 |
| Q: 1.WHAT IS SPECTRUM ANALYZER? 2.WHAT IS NETWORK ANALYZER? 3.WHAT ARE THE DIFFERENCE BETWEEN SPECTRUM ... A: These pages offer a lot of information and many useful links about network and spectrum analyzers: ... | |
| Filters of light | 8/24/2007 |
| Q: If we can filter out certain color and UV wavelengths, is it possible to 'snapshot' higher frequency ... A: I can interpret what you are describing in tow ways. The first is "aiasing," that is, the effect ... | |
| Alternative EM radiation absorption avenues | 8/11/2007 |
| Q: a known scientist stated that we are constantly being bombarded by solar UV and Gamma rays. Lead is ... A: Water is highly transparent to UV A, B, and C light, to the extent that water light guides are often ... | |
| Diffraction and Holography | 8/10/2007 |
| Q: I understand that transmission holographs redirect photons from the reference beam to follow vectors ... A: You should look at the Huygens–Fresnel principle of diffraction. You can think of the plate as a ... | |
| sight & speed of light | 8/6/2007 |
| Q: If we are always seeing in the past, if we could see at the speed of light, would we be seeing into ... A: Sue, I am intrigued by the concept of "seeing at the speed of light." Do you mean that you are ... | |
| Air traffic / Fm interference | 7/29/2007 |
| Q: I live about 10 km from the Indianapolis airport on the approach to runway 32. I occasionally ... A: Mike, I'm not the best person to ask, but here's a shot. It looks like air traffic frequencies are ... | |
| dispersion | 7/9/2007 |
| Q: can dispersion of white light take place when light is incident on a hollow prism? If not why? pleae ... A: Sure, just not very much. Passing light through a hollow prism is effectively the same as passing ... | |
| Visibility | 7/6/2007 |
| Q: I was wondering if there is anyway to see through fog? I was thinking this on the way home from work ... A: Other portions of the light spectrum, including terahertz (THz), millimeter, and radio frequency ... | |
| physics for living | 7/3/2007 |
| Q: I'm wondering if you can name some great books on physics for non-physicists. There are two types ... A: I read a decent amount of science and physics nonfiction, but I tend to read more philosophical ... | |
| prism | 6/27/2007 |
| Q: Hey I am a land surveyor and we use an instrument that shoots infrared into a prism and the prism ... A: The prism is called a corner cube retroreflector. If you had a cube of glass, you get a corner ... | |
| EM waves | 6/15/2007 |
| Q: hell sir im 20 year old n doin my graduation in physics. i hav few questions regarding EM waves how ... A: EM radiation emitted by the sun is formed many ways, including blackbody radiation and radiation ... | |
| Best Position to Place Color Filter | 6/14/2007 |
| Q: Hope all is well. A question on the best position for placing a color filter in a home made camera. ... A: Usuff, Placing the stop away from the intended location has two detrimental effects: 1. ... | |
| Lab Scenario | 6/13/2007 |
| Q: I'm 16 and in a lab physics course. Suppose you placed a cubic contained of water and scattering ... A: You have inserted a Rayleigh scattering medium in the light beam. There will be no polarization ... | |
| Best Position to Place Color Filter | 6/11/2007 |
| Q: Hope all is well. A question on the best position for placing a color filter in a home made camera. ... A: You want to put the filter as close as possible to the lens stop. The reason is that the light is ... | |
| lens | 6/6/2007 |
| Q: my name is john im 17 years old n a physics student this is regarding the experiment i did to find ... A: Lenses create an image of the object (the needle, in this case) on the other side of the lens. The ... | |
| intensity | 6/1/2007 |
| Q: How are you? Very well I hope... I'm actually struggling with an optics question that I hope you ... A: Mutual coherence is the fourier transform of the source intensity distribution. Unfortunately, I ... | |
| Invention of the Laser | 5/23/2007 |
| Q: I am researching the "inventor of the laser" and have stumbled upon the Gould vs. Bell Labs ... A: As with many inventions involving both physics and engineering, the credit for inventing the laser ... | |
| Heat transfer from very hot surfaces to surrounding structures | 5/20/2007 |
| Q: I am 36, have a BSc and honours in medical sciences and a limited understanding of physics and ... A: 400 C is pretty tough for most plastic materials. Most will deflect at much lower temperatures, so ... | |
| light | 5/10/2007 |
| Q: While deriving the formulae for the focal length of lenses,we consider signs(+/-). But why then do ... A: I apologize for the delay. Questions have not been getting through to my email account. When ... | |
| Best surface for judging focus | 5/6/2007 |
| Q: Trust all is well. I throw a focussed moving beam of light (from a tungsten filament bulb) onto ... A: All is well. I am having a problem with allexperts, though. It seems that none of their emails are ... | |
| Lightning balls | 5/2/2007 |
| Q: What makes those "lightning ball" toys you can get in science stores work? And also can you make ... A: James, There are many terms for the device you describe, but "plasma globe" is one of the most ... | |
| holography | 4/25/2007 |
| Q: Why the inverse picture of an objec appears in holographic photos in addition to the main direct ... A: Note that not all holograms have inverse images. You are describing holograms made by the ... | |
| Neutron-light interaction? | 4/22/2007 |
| Q: I've been taught that electrons oscillate when light is incident on them.They oscillate in the ... A: Neutrons have a weak interaction with EM fields (light) because of their constituent, charged ... | |
| car windows and polarized sunglasses | 4/20/2007 |
| Q: Curtis - I wanted to ask a further question, but you were unavailable, so I asked Scott Valentine. ... A: The patterns you see are caused by thermal contraction during the cooling of the glass after it is ... | |
| patterns in glass of car windows when viewed through polarized sun glasses | 4/17/2007 |
| Q: When viewing car windows through polarized sun glasses, patterns in the glass appear. Is this due ... A: I have a pair of polarized sunglasses and I have observed this effect many times. There is more ... | |
| First Surface Mirrors – Differences in “Quality”? | 4/5/2007 |
| Q: How are you? A question on first surface mirrors - are there any differences between the various ... A: I'm very good, but busy. Highreflective does not provide enough information to verify how well ... | |
| Lenses | 4/4/2007 |
| Q: I was wondering about a question that came up in class the other day - there was a two lens system. ... A: You have handled the first lens fine, so I will address only the second lens as an independent ... | |
| receivers | 3/17/2007 |
| Q: What do the terms homodyne receiver, heterodyne receiver, intradyne receiver stand for? (please ... A: Heterodyne and homodyne are two basic classes of nonlinear frequency downconverters. The former uses ... | |
| Polarization | 3/11/2007 |
| Q: Wow, a light specialist. You seem to be the one that I need to talk to. Getting to the matter, I ... A: Kaleb, Sorry for the late reply. I can't exactly tell from your sky description whether your ... | |
| don't know who else to ask! | 3/4/2007 |
| Q: Since you asked, I graduated from high school last year and didn't do very well in physics... my ... A: There is an excellent discussion of this topic on this web page: ... | |
| Colour - wavelength or frequency? | 2/23/2007 |
| Q: What is the colour of light a characteristic of ; the wavelength of the wave ,or its frequency? I ... A: Light waves are an oscillating electromagnetic field. The most characteristic property of light is ... | |
| Laser Projectors | 2/17/2007 |
| Q: You gave reference to this website: http://www.laserfx.com/Works/Works3.html This looks like the ... A: Typically the laser is fixed and there is a tiny, activated mirror to steer the beam into a pattern. ... | |
| Magnification - Why Two Systems | 4/26/2006 |
| Q: Followup To Question - Welcome back! In studying lens I'm puzzled by the fact there are two ways ... A: The wiki article is good, but it uses a simple sign convention. The authors have chosen a convention ... | |
| Holograms | 4/23/2006 |
| Q: I was curious of how one could create a hologram. I wasn't sure if there are different kinds of a ... A: One could never make a hologram of niagra falls itself for several reasons. Here are two: 1. It is ... | |
| how could this be true? | 4/21/2006 |
| Q: my name is matt volkert, i'm 21 years old with 3 years of college experience at UVA and i'm studying ... A: Not opitcs questions, but easy enough: 1. When your car suddenly stops, you feel a force pulling ... | |
| Questions | 4/20/2006 |
| Q: I actually have a few questions about light and figured there was no need to max you out by sending ... A: 1. holograms are made by interference of light. They can be designed by fast computers as well. The ... | |
| energy diagrams | 4/18/2006 |
| Q: I hope I'm finding you in the best of health. I'm 16, in high school and I thought I nunderstand ... A: This is a trick question of sorts. The atom can relax to the ground state two ways: 3->2->1 (two ... | |
| Magnification - Why Two Systems | 4/10/2006 |
| Q: Welcome back! In studying lens I'm puzzled by the fact there are two ways of expressing a lens' ... A: Good to hear that you have been busy. Certainly I have, which is why I have been "on vacation." ... | |
| light reflection | 11/28/2005 |
| Q: When light is reflected, how can the photons change the direction of travel instantly with no ... A: A: Photons don't really change direction instantly. Photons themselves do not accelerate (they have ... | |
| light | 11/26/2005 |
| Q: my age is 24 and i stud children between (12-14)years the subject of question is the light the ... A: How does vision work: http://science.howstuffworks.com/eye.htm Optics for 12-14 years: I ... | |
| Fiber Optic Light Guide - Where to Obtain | 11/24/2005 |
| Q: I've got a couple of questions - I've put up a webpage as it's easier to explain the question. It's ... A: I'll send you fiber information soon. Generally speaking, the output end of the fiber must be the ... | |
| Lens Magnification Formula | 11/21/2005 |
| Q: Curtis, Many thanks for your earlier reply letting me know the minimum value of R needs to be 4*f ... A: To answer your question directly, your image will be out of focus is you try to force R<4*f. ... | |
| UV light ink | 11/16/2005 |
| Q: I couldn't find someone who specialized in inks or chemestry, but I had a question about that hand ... A: It could certainly work, but I think you would have to be sophisticated to create ink of the proper ... | |
| Lens Magnification Formula and Light Source Question | 11/12/2005 |
| Q: I've got a couple of questions - I've put up a webpage as it's easier to explain the question. It's ... A: FirstThe equation for magnification has lost one of the constraints of the equations that are used ... | |
| Would you have to go the speed of light to reach the speed of light | 10/22/2005 |
| Q: the speed of light is constant about 6 million miles per second or somthing. now as you approach ... A: Time dilation is tricky. If you measure your own speed using distances measured in the motionless ... | |
| Travel faster tha light | 10/14/2005 |
| Q: It is well known that nothing could travel faster than light (C) and also that motion is relative. ... A: By classical mechanics, your two bodies would exceed the speed of light (which would not violate ... | |
| Light:? | 10/12/2005 |
| Q: I came across this question and im confused: A sheet of red paper will look black when illuminated ... A: I'm not sure what you mean by "category." With regards to human response, there are three colors: ... | |
| Variable Index of Refraction | 10/11/2005 |
| Q: Hey there! I was just having a little doubt here: Is there any material bearing the property of a ... A: Refractive index is a linear electromagnetic property of materials. Therefore, it cannot be varied ... | |
| Light - colour | 10/9/2005 |
| Q: I am forty years old! with a degree in Engineering. For the past 5 years I have been teaching ... A: Amanda, The effect is purely visual. For starters, light of different wavelengths (colors) does ... | |
| speed of light questions | 10/6/2005 |
| Q: I'm a layperson interested in some aspects of physics. I wanted to ask you some questions about ... A: Mr. Thomas, Popular physics has grossly misrepresented the nature of light, specifically ... | |
| How do we see the colour of a red book? | 10/2/2005 |
| Q: I am a student teacher. My science knowledge goes up to high school level. I have to give a ... A: Jacqueline, The recognition of color is a result of physical, biological, physiological, and ... | |
| Lens Question | 9/30/2005 |
| Q: I need some help with lenses again! Any help appreciated. I've put the question up as a webpage ... A: Usuff, 1. Consumer mirrors are made from a plate of glass with a layer of aluminum on the back. ... | |
| Lens Question | 9/28/2005 |
| Q: I need some help with lenses again! Any help appreciated. I've put the question up as a webpage ... A: Very nice image. There are a couple of problems with decentering your optics: 1. The translation ... | |
| light | 9/27/2005 |
| Q: i am a senior in high school and Ive been interested in theoretical quantum physics since 8th grade. ... A: Bill, I have a metaphor for you. Q: Is liquid a gas or a solid? A: Liquid has properties of gas ... | |
| Supersonic Optical Phenomena | 9/12/2005 |
| Q: A friend sent me several pictures of a cloud/shock wave which formed around a jet plane probably ... A: Don, This is a popular image in engineering circles. I found it on this web page, along with a ... | |
| Directionality of Thermal Reflections/Emissions | 9/7/2005 |
| Q: Why do non-conductive materials reflect (thermal radiation) better at large angles to the surface ... A: Steve, You have mixed two principles which are better understood separately: 1. Metals reflect ... | |
| Wheels spinning backwards | 8/29/2005 |
| Q: What is the reason that, let's say a car tire, looks to be spinning in the correct direction ... A: Andrew, This effect is called "aliasing." Aliasing means that a phenomenon characterized by a given ... | |
| Condenser Lens - How to Use | 8/25/2005 |
| Q: Curtis, I need some help with condenser lenses. I've put up a webpage with a few questions at :- ... A: 1. When measuring S2, you should take the distance from the curved surface rather than the flat ... | |
| Through how thick matter x-rays... | 8/22/2005 |
| Q: Through how thick matter x-rays can pass (it is clear, that it pass less through the harder matters ... A: The transmission of x-rays depends predominantly on the type of matter, thickness of the matter, ... | |
| focusing light | 8/21/2005 |
| Q: I'm 26. I don't have any courses under my belt but I'm just generally interested in physics. I'm ... A: Greg, As a result of diffraction, the smallest theoretical size to which light of a given ... | |
| science experiments | 8/16/2005 |
| Q: I'm 13, 8th grade, and I really don't know alot about science of any kind yet, but i'm interested in ... A: Erica, I would recommend looking for science fair project ideas on the web. This page looks like a ... | |
| The speed of light........ | 8/15/2005 |
| Q: I'm not sure whether you can help but here goes anyway. A work colleague sent me the following ... A: It is impossible to travel at or faster than the speed of light, but you may travel close to the ... | |
| infra red rays | 7/21/2005 |
| Q: sir, why is that infra red light is able to peneterate through mist and fog? why is it not ... A: Charu, Your statements seem incorrect to me, but it depends on the exact wavelength in question. UV ... | |
| Thin Lens Equation - Can't Get to Work for DCX Lens | 7/14/2005 |
| Q: I couldn't get the thin lens equation to work for me with a double convex lens. I placed an object ... A: Ok, the addition of the second lens makes a big difference. You can use "gaussian reduction" to ... | |
| Thin Lens Equation – Can’t Get to Work for DCX Lens | 7/12/2005 |
| Q: I couldn't get the thin lens equation to work for me with a double convex lens. I placed an object ... A: The Lissajous figure is very nice. I had never heard the term before. I tried adding a fixed ... | |
| A few Questions on Lenses | 7/6/2005 |
| Q: A few questions on lens, if I may. 1) Is there a convention for stating lens magnifications? The ... A: Usuff, I messed up because I did not notice that the lens was a negative focal length. I should ... | |
| A few Questions on Lenses | 7/5/2005 |
| Q: A few questions on lens, if I may. 1) Is there a convention for stating lens magnifications? The ... A: 1. One cannot distinguish an Nx lens from a 1/Nx lens because the former can be turned around to ... | |
| Chromophore | 7/4/2005 |
| Q: 1...Please tell me what is the meaning of "Chromophore" in UV? 2...And what is the meaning of ... A: I assume that you have an issue with the concept of "color" when one is talking about UV light. You ... | |
| a question about emitting light | 7/2/2005 |
| Q: I am a Uni student .I learned something about direct and indirect semiconductor .They said that ... A: I think this summary will answer yourhttp://ece-www.colorado.edu/~bart/book/book/chapter4/ch4_6.htm ... | |
| Interference question | 7/1/2005 |
| Q: I have a question that bothers me for a while now and it appears that I cannot find a satisfactory ... A: The answer to this question varies, depending on whether the wave is finite or infinite. Infinite ... | |
| origin of reflected and refracted way | 6/9/2005 |
| Q: I just learnt that wave propagation is due to the oscillation of charge, thus varyinig electric ... A: Steven, If I am interpreting your question correctly, you are concerned about how the direction of ... | |
| Thin Lens Equation | 6/3/2005 |
| Q: Curtis, [snip] An aside - why is it called the "thin" lens equation when the lenses it applies to ... A: I should take some time to introduce the concept of "paraxial optics," or "first-order optics." ... | |
| How to Find Values for S1 and S2 | 5/31/2005 |
| Q: Followup To Question - Hi Curtis, Many thanks again for the earlier reply giving me the thin lens ... A: Finally, an answer that is not quadratic! (1/m + 1)*(1 + m) = R/f The thin lens equation applies ... | |
| How to Find Values for S1 and S2 | 5/24/2005 |
| Q: Many thanks again for the earlier reply giving me the thin lens equation : 1/S1 + 1/S2 = 1/f ... A: Usuff, You can calculate M without S1 and S2, but the form is again quadratic. There are two ... | |
| How to Find Values for S1 and S2 | 5/22/2005 |
| Q: Many thanks again for the earlier reply giving me the thin lens equation : 1/S1 + 1/S2 = 1/f ... A: Usuff, The two equations form a quadratic when you combine them. Let R = S1 + S2, then S1^2 - ... | |
| Surface Plasmon Phenomenon | 5/16/2005 |
| Q: May everything orients in your favor. I've been graduated in chemical Eng. (BS). My question is ... A: I'm not exactly sure at what level you are trying to understand plasmon effects. My best advice for ... | |
| Sunlight | 5/15/2005 |
| Q: Why does sunlight have a bleaching effect ? I have a number of books on my shelves that are in ... A: Mark, The bleaching is a result of what are called "photochemical reactions." The organic dyes ... | |
| Ligh in two places at once | 5/12/2005 |
| Q: I recently heard that light has been photographed in two places at once. That is, the same photons ... A: The location of a photon can be uncertain enough to conclude that it exists in two places at once. ... | |
| Speed of light. | 5/11/2005 |
| Q: I am 19 and i am a university student studying engineering. At current i am reading a book named ... A: There isn't a "why" to answer your question - that's simply the way it is. Only massless fields ... | |
| charge | 5/9/2005 |
| Q: I have a simple question. What really IS 'charge'? I know a electron has negative charge and a ... A: Ken, Charge is a fundamental property of matter. Therefore, it cannot be defined in any more ... | |
| Plastic Lens - Any Good? | 5/7/2005 |
| Q: I'm interested in obtaining large diameter (10 - 15cm) negative lens with short focal lengths (say ... A: Plastic lenses can be as good or better than glass, but more likely they are not as high quality. ... | |
| Light | 5/4/2005 |
| Q: A 2 part question. First when was the speed of light first measured and how was it measured ? ... A: This web page wll answer the ... | |
| Any Formula for Using Enlarging Lens as Macro Lens? | 5/3/2005 |
| Q: I am photographing objects at close distances, around half a metre away, with both a 35mm and medium ... A: Usuff, Thank you for the drawing. Yes, there is a formula, but first I will introduce a few ... | |
| rear car windows, polarisation of light | 5/2/2005 |
| Q: my name is Maarten, 20 years old, student engineering sciences. I was told that the rear window of a ... A: Maarten, Glass is put under pressure when installed, and it might have polarizing properties, but ... | |
| light | 4/22/2005 |
| Q: Please tell me how do e.m. waves reflect when hitting an object. Does the light bounce of the ... A: EM waves reflect because of vibrating electrons in the object. Whether the electrons are located on ... | |
| photon types | 4/20/2005 |
| Q: Several questions for you... 1. As far as I understand, UV and infrared are considered light. Are ... A: 1. Yes, The term "light" can apply to any electromagnetic wave. Thus, gamma, x-ray, UV, visible, IR, ... | |
| Concave lens/parallel rays | 3/24/2005 |
| Q: I am a physics student. 16 years old. 3 questions about light rays and lenses: why are light rays ... A: 1. Light rays from distant sources are diverging so little that they may be treated as parallel. ... | |
| Black body radiation | 3/22/2005 |
| Q: I'm interested in the maximum temperature an object can reach when being heated by radiation. I'm ... A: You must be hard core to be worrying about whether you can exceed 5700 K - after all, there is ... | |
| theoretical use of magnifier | 2/22/2005 |
| Q: Age 40, Upper second class history degree, Working knowledge of A level optics. This may be be ... A: Denise, This is right up my alley! I will give you the answer, and let you do most of the thinking ... | |
| reflection. | 2/16/2005 |
| Q: you have said to apply lens maker formula.You see lens maker formula is approximation, not exact ... A: Lens maker's equation is exact if you use it with the appropriate cardinal points. In the case of a ... | |
| photocell for pinwood derby car | 2/14/2005 |
| Q: My son wants to add simple sounds to his boy scout pinewood derby car. I have the Radio Shack ... A: Your photocell lowers its resistance with increasing light level. To make a switch from this, you ... | |
| reflection. | 2/12/2005 |
| Q: sir , there is an object and a reflective surface is placed in front of it. now how do we find out ... A: This is a mathematically complex subject. I don't have and idea what your background is, so I will ... | |
| electrical spark phenomena | 2/10/2005 |
| Q: There are several electrical spark phenomena; lightning, electric arc light (also called klieg ... A: Carl, 1) Most of the light produced by electric arcs is created by process of gaseous discharge. ... | |
| e=mc2 | 2/8/2005 |
| Q: Age 60; Graduate in History; elementary grasp of subject. Can you please explain the c2 part of ... A: The full form of the equation is this: E^2 = (m0^2 * c^4) + (p^2 * c^2) E is the total energy of ... | |
| Diffraction grating question | 2/6/2005 |
| Q: If I have the relative intensity [I(x)/I(x=0)] of a diffraction pattern created by shining a HeNe ... A: Your diffraction pattern will be composed of a series of bright dots. The dots will be spaced ... | |
| Trapping Light | 2/4/2005 |
| Q: Is it possible to trap light? Light reflects off objects and disperses but what if it had nowhere to ... A: There is no such thing as a perfect reflector. Light reflects off of the walls of the mirrored box ... | |
| Frequency | 1/25/2005 |
| Q: Sir, I am fairly good in Geometrical and Wave Optics and can comprehend quantum mechanics to an ... A: The frequency stays constant, but the velocity of the waves changes. Therefore, the wavelength must ... | |
| Frequency | 1/23/2005 |
| Q: Sir, I am fairly good in Geometrical and Wave Optics and can comprehend quantum mechanics to an ... A: Sanjeth, Your reasoning is correct, but you can also think of it as a mechanics problem. Light ... | |
| Stroboscopic effect | 1/20/2005 |
| Q: I am over 50 and have a BS in engineering. Why doesn't the stroboscopic effect cause flickering of ... A: The effect is called "aliasing" when the apparent spatial or temporal frequency is different from ... | |
| Solar Energy | 1/19/2005 |
| Q: I am a high school student attending Hamilton High School in Los Angeles, California. I need to do a ... A: Sergio, The science is very simple. Absorbed light becomes heat. The more light collected, and the ... | |
| Speed of Light | 1/15/2005 |
| Q: Curtis, I have two questions for you about light. I am an accountant so I would appreciate it if ... A: Paul, Thanks for the rating. I saw your additional question in your comments. Some people call ... | |
| Series circuit | 1/8/2005 |
| Q: I did an practical experiment in my school. The experiment was to make a series circuit with three ... A: What you describe is commonplace when you run lights in series without a bias resistor. While the ... | |
| Laser acceleration | 1/5/2005 |
| Q: "The "something simple" is the doppler shift. I found a convincing-looking discussion here: ... A: It appears that I send a dynamic link. My apologies. The abstract page might be static: ... | |
| Laser acceleration | 1/4/2005 |
| Q: I am currently a second semester sophomore and have a decent understanding of light and the ... A: Aaron, The "something simple" is the doppler shift. I found a convincing-looking discussion here: ... | |
| atom | 12/18/2004 |
| Q: Let's say you have a smooth wood table and on top of it a rough stone. I assume the table, the ... A: The question of smooth vs. rough is easy. In one case, all the atoms on the surface are aligned in a ... | |
| Space expansion: what exactly is it doing to photons? | 12/17/2004 |
| Q: I am trying to understand how the expansion of spacetime is "stretching" light, for example the ... A: Frank, Sorry for the long wait. As I understand it, photon-matter interactions in the first ... | |
| How to Get Black, Non Reflective Surface | 12/15/2004 |
| Q: I do some photography where I shoot in the dark. I've painted some surfaces with black paint so ... A: I think that black felt is the optimum "cheap" black material. There are things even better, but ... | |
| Light waves I guess | 12/14/2004 |
| Q: age:67! level of education re physics|: pretty low. Q: If the light we see from stars is many light ... A: Deep space is pretty much a vacuum, so light from distant stars does not disperse very much. There ... | |
| optics | 12/13/2004 |
| Q: my name is vineeth venugopal and iam a student of class 12 in india. i have basic education in both ... A: You are welcome to ask optics questions as you wish. I allow only one question per day because of ... | |
| How to Get Black, Non Reflective Surface | 12/8/2004 |
| Q: I do some photography where I shoot in the dark. I've painted some surfaces with black paint so ... A: Even the best black paint applied with the best technique is about 5% reflective at normal ... | |
| Speed of Light | 12/6/2004 |
| Q: Age 70, B.Sc, B.Ed (retired high school math teacher) - I sometimes filled in for the science ... A: My apologies for the long delay, Rick. Your email got lost in my spam filter. I will try to make it ... | |
| field of view | 12/1/2004 |
| Q: Ok I have been searching the Internet for the answer to this question but I have come up empty ... A: The field of view (FOV) of the human eye is almost an entire hemisphere, or 180 degrees. Your brow, ... | |
| rainbow | 11/12/2004 |
| Q: I have just studied that the rainbows are formed by the refrective index on the water droplets, I ... A: Rainbows are formed by light passing through spherical water droplets. They are formed at angles of ... | |
| Hi Curtis, I noticed that... | 11/8/2004 |
| Q: I noticed that the sunlight during the fall seems to be different than the sunlight during summer. ... A: Doug, 1. The sun is much lower in the sky in autumn, meaning that 10-15% less light flux hits the ... | |
| what does sunlight look like? | 10/28/2004 |
| Q: Age 52, Associate of Science in Business. Understanding of the subject: basic, but like to read ... A: David, Light is a travelling electromagnetic wave. As such, it is essentially a form of energy. The ... | |
| light | 10/24/2004 |
| Q: Explain the relationship between light, electricity, and the entire range of the electromagnetic ... A: I can't specifically comment on the book since I have not read it. I am generally a skeptic, so I ... | |
| measuring voltage | 10/19/2004 |
| Q: im 16, a 1st year college and im about to ask you, w/c is more economics, 50 watts incandescent bulb ... A: The two bulbs will cost about the same to operate, depending on your exact electricity cost. The ... | |
| light | 10/17/2004 |
| Q: Explain the relationship between light, electricity, and the entire range of the electromagnetic ... A: Light and electricity are very different. Electricity is the movement of electrons (which have ... | |
| Halogen burnout | 10/15/2004 |
| Q: When I was moving into a new address, the landlord did some wiring for the room that was to be my ... A: Herb, Most likely you just burned through the bulb filament. You can replace the bulb quite easily. ... | |
| spectra--visible light | 10/12/2004 |
| Q: I have some follow-up questions. (I think the original Q&A are printed below) My book has a graph ... A: David, You are studying what can be an extremely confusing topic - standard radiometric units and ... | |
| spectra--visible light | 10/8/2004 |
| Q: I am studying physics on my own, using college textbooks. I would lke to confirm something I have ... A: Your theses is essentially correct. Using planck's law, one can easily calculate the number of ... | |
| telescope | 10/3/2004 |
| Q: Can you please explain me how can we create a simple/good refracting telescope at home? Also please ... A: The list of requirements and specifications are too large for me to answer. Instead, I recommend ... | |
| microwave combine with smoke detector | 9/21/2004 |
| Q: how many times have we burnt our popcorn? Many! that's y i want to design a microwave that ... A: Very interesting. I'm not sure that carbon dioxide is the dominant byproduct of overcooking. That ... | |
| the spectrum beyond | 9/18/2004 |
| Q: What lies beyond the shortest and the longest electrodynamic waves, why should there be a limit to ... A: There is no such thing as the shortest and longest electromagnetic wave. The electromagnetic ... | |
| FTL communication | 9/17/2004 |
| Q: It occurred to me to wonder: if we had an observation post halfway between us and another star ... A: On the first point, you are correct. Any signal from the observation post would also travel at the ... | |
| Sunlight, UV rays and vitamin D | 9/14/2004 |
| Q: I in my 30's and hold a B.Sc. Can you tell me if both types of UV rays penetrate regular window ... A: Not sure what you mean by "both types of UV." UV is a continuous spectrum of light from 1000-400 nm ... | |
| Rifle Scopes | 9/6/2004 |
| Q: I am a 43 year old man with a college degree, but very little knowledge of rifle scopes. My ... A: I think this page had a quick summary of ballistic compensation: ... | |
| Red eye | 9/3/2004 |
| Q: Why do we have red eye in the photograph? A: Shawn, Redeye is caused by the reflection of light off the back of your eye (the retina). The ... | |
| red light | 6/3/2004 |
| Q: Many light bulbs used for gardening have specific bandwidths of light that they output, in the red ... A: Good question, and one about which I have recently wondered. I dropped the $10 on a fluorescent ... | |
| light As Physics | 6/3/2004 |
| Q: Would you please explain this problem, (C) --- (ii) only? I have the answers-----still cannot ... A: Jane, This problem assumes that the footprint of a pixel is proportional to the distance ("range") ... | |
| Optics | 6/2/2004 |
| Q: Have you seen those outer space sci-fi movie where you have this kind of computer/machine where they ... A: Light cannot reflect of bend in free space. For you to see light, it must either 1. be directly ... | |
| vision | 5/31/2004 |
| Q: How far can a standing 6 foot person see out toward the horizon A: To calculate the distance to the horizon in nautical miles use the following formula: Distance to ... | |
| The specific property of black colour | 3/9/2004 |
| Q: my name is Andrius (Andrew in english:). I'm a young physicist from Lithuania studying in Vilnius ... A: 1. The color of an absolute blackbody depends on its temperature. If the temperature is less than ... | |
| Finding the refractive index | 3/9/2004 |
| Q: I am 17, and leaving school at the end of the year, I am doing advanced higher physics (equivalent I ... A: I am a little bit confused by your apparatus. Here's my best guess: 1. You have a concave mirror ... | |
| a question about uv light | 3/2/2004 |
| Q: I am currently taking first year physics in university and something that we were learning about ... A: Ultraviolet is broken into three bands based on wavelength, UVA, UVB, and UVC: UVA 400 nm - 320 nm ... | |
| Is Speed of Light Absolutely Constant? | 2/27/2004 |
| Q: I was taught in school that c is constant, regardless. However the refraction of light in glass is ... A: Usuff, This is a misunderstanding that I hear about all the time. The speed of light is constant ... | |
| laser | 2/21/2004 |
| Q: I am a researcher.I want to know that which chemical quickly give colour change on exposure to He-Ne ... A: I could not find any reference to the material you mentioned, or to any other photochromic dyes ... | |
| optical | 2/20/2004 |
| Q: i very good morning sir, my quenstion is, when a very high- melting point object's heated it will ... A: The phenomenon you are interested in is called "blackbody color". The spectrum of light extends from ... | |
| photoelasticity and stress factors | 2/17/2004 |
| Q: i am 17 years old, a junior in high school, and doing a science fair project on photoelasticity and ... A: Keri, I gather that you are using photoelasticity to determine the amount of stress on a window. I ... | |
| Second Length | 2/16/2004 |
| Q: "Second" is probably the basic unit of time. I have a question. Why the length of a second is "One ... A: The definition of a second is arbitrary. At some point in ancient history, the Egyptians divided a ... | |
| Laser pointer guy again. lol. | 2/10/2004 |
| Q: I have yet another question for you related to laser pointers. lol. You say that the diodes are ... A: I tried to find a decent page on laser diode technology, and this seems to be the best: ... | |
| magnitized water | 2/9/2004 |
| Q: I am eleven years old, i am in junior high school. i don' understand this topic much all i know is ... A: I think that water magnetization is a scam. Look here for information: ... | |
| Laser pointer and eyes | 2/7/2004 |
| Q: Sorry that this one won't stretch you. It must be an easy one. Those laser pointers used in ... A: Art, No, those lasers are not dangerous to people or any large animals. Their power is firly low, ... | |
| Blue lasers | 1/31/2004 |
| Q: This time my question will strickly be about light. lol. I've been wanting to buy a blue laser ... A: James, You will have to wait a little while to buy a cheap blue laser pointer. The reason is quite ... | |
| diffraction grating/interference | 1/29/2004 |
| Q: I performed an experiment passing light from a sodium lamp through a coarse diffraction grating, ... A: Pete, You have not told me much about your apparatus, but it sounds like you might have imaged the ... | |
Physics
Answers by Expert:
Optics C
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I am interested in answering general questions about optical phenomena, devices, experiments, and instrumentation. I have a special interest in the properties of light, interaction of light and matter, and interaction of light and humans (visual optics). Ask me anything to do with light!
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I have a classical training in optics, optical phenomenology, optical modeling and laboratory experimentation. I work for a major university research laboratory specializing in infrared optics .
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Ph.D., Optical Physics
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