Diffraction Definition and 1000 Threads

Homework Statement The intensity of light I in the fraunhofer diffraction patter of a single slit is I=I0(sin\gamma/\gamma)2 where \gamma=\piasin\theta/\lambda Show that the equation for the vaules of \gamma at which I is maximum is tan\gamma=\gamma well, intensity is...

Hi, I was conducting an experiment on a material using XRD and I investigated two cases. One case is the presence of outside electric potential, that is, the material being connected to a electric circuit. The other case is the absence of this electric potential. I found that the two XRD...

Homework Statement When i see the back of a CD or DVD, there is a spectrum, in which the various colours are overlapping with each other(continuous spectrum) Homework Equations What is the reason for this phenomenon, diffraction or dispersion? The Attempt at a Solution Diffraction...

Homework Statement The distance between crystal planes in a KCl crystal is about 3.14 \times 10 ^{-10}m. Calculate the Bragg's reflexion angle of first order for electrons with kinetic energy of 4keV. Compare it with photons that have the same energy.Homework Equations \lambda n =2d \sin...

Hello World, I'm suffering a lot about light diffraction and I need help I can't really imagine the idea of diffraction What is an Airy disk?and what does it represent?Does it represent the image of the hole at which diffraction takes place?Is that the reason why the shape of airy disk...

Hi, I have tried tackling these question but I am simply absolutely lost... 1. A single slit of width 1.50 um is illuminated with light of wavelength 500.0 nm. Find the angular width of the central maximum. I have no attempt for number 1. 2. Microwaves of wavelength 2.8 cm fall on...

Homework Statement Light consisting of two nearly equal wavelengths L and L+dL, where dL << L, is incident on a diffraction grating. The slit separation of the grating is D. Show that the angular separation of these two wavelengths in the m'th order is dTheta = dL / ((D/m)2+L2)0.5...

I was wondering what occurs when a diffraction grating is produced with features smaller than a wavelength of visible light. If the pits in a CD were made to be only a few tens of nanometers wide, what would we see?

Explain the concept of missing orders in case of double and n slit diffraction.

Homework Statement A beam of monochromatic light is incident on a single slit of width 0.560 mm. A diffraction pattern forms on a wall 1.35 m beyond the slit. The distance between the positions of zero intensity on both sides of the central maximum is 2.32 mm. Calculate the wavelength of the...

Hi, Going through a Physics problem in class today my teacher stated that we could only resolve if: θ = λ/b. Why? Is it because when that does not follow, there is no "black spot", therefore that light source can merge with another one? Thanks, Peter

I was curious as to how semiconductor manufacturing gets around the fact that diffraction should prevent processors with transistors on the scale of tens of nanometers from being possible. How do we get around this if the diffraction of light is a fundamental limit to how small we can do any...

Hi there, I understand somewhat how diffraction works in terms of the aperture of a camera lens and the resulting loss in resolution in the image, but my question is: Is the degree of diffraction only dependent upon absolute aperture size, or the size of the entrance pupil? For example, f/22...

Homework Statement I was a asked a question from an experiment: What happens if the light shone into the diffraction grating or a double slit is not perpendicular to the diffraction grating or double slit? What will happen?The Attempt at a Solution Straight away i can tell that the light...

When white light is passed through the slits in the grate and hits a screen some distance away from the grate, different order spectra appear. My textbook tells me that violet light is always closer to the zeroth order bright fringe than red light because it has a shorter wavelength. However...

Homework Statement I've been reading a book about waves. I skipped the test earlier this year because I had not done any problems and thought it would be a waste of time to try. But now I kind of have to do it, I've re-read the book but it's much to understand and remember. Especially the...

Hey guys, In diffraction of light, why must the slit width be of comparable size to the wavelength of the light being shone on it for diffraction to be noticed most? Thanks

When firing electrons at a small slit, does the resulting interference pattern appearing on a screen behind the slit change significantly depending on whether the electrons are "aimed" at the center of the slit compared to the edges of the slit? Any references with more info about this?

if i have two in coherent waves then will interference and diffraction be noticeable? if yes then to what extent and what factors matter?please xplain

What is the mechanism of diffraction? Let's consider water waves and not light; if we consider water an aggregate of little molecules, why would a chain of molecules moving up and down (the wave) suddenly turn once passed through a slit? I hope I'm clear enough.

Could someone explain what the 'first order' diffraction peak is?

Hello In an electron diffraction experiment usually the diffraction rings are blurred. My question. If measuring the diameter, should I measure to the inside of the ring, the outside, or take a guess where the middle of the ring is and measure to there? Thanks

-------------------------------------------------------------------------------- Hope somebody can help me. I am studing perovskite hydride CaCoH3 using X-ray diffraction. CaCoH3 crystallizes with a cubic in space group Pm-3m. At phase transtion point, all peaks weakened gradually, and...

I know how photons are diffracted round a corner in quantum mechanics. But is there also an explanation in classical electromagnetic theory (i.e. by Maxwell's laws?) Imagine there was an EM wave traveling purely normal to a slab of material which is highly attenuating, but which has a small...

i just don't understand diffraction in a double slit , ? how is it related to interference?? like if i want to find how many bright fringes within the central bright fringe of the diffraction envelope? or how many bright fringes are found between the bright fringes of the first and second of...

A diffraction grating with 600 lines/mm is illuminated with light of wavelength 500nm. A very wide viewing screen is 2.0m behind the grating. b.) How many bright fringes can be seen on the screen. MY ATTEMPT: i worked out the angular separation between bright fringes to be 0.305 rad (i...

Hi, I'm trying to perform a double slit diffraction experiment without using a laser, but instead using a super-bright, white LED. This LED has been placed inside a sealed box with a small pinhole opening (~1/32 inch diameter). This however introduces the problem that the light is incoherent...

This is in my book: exp[2\pi i(hx+ky+lz)][1+exp(\pi i(h+k+l))]=2exp[2\pi i(hx+ky+lz)]\cos^2[\frac{\pi}{2}(h+k+l)] And in order for the cosine not to be zero, h+k+l must be even when we want to see the reflection. But I think that the result should be exp[2\pi...

Can anyone tell me the difference between interference in double slit's and single slit diffraction?

Hello all. I have a relatively simple question. I have learned very recently about wave optics and the resulting diffraction patterns. The experiment by Thomas Young was used to explain the topic and the equations were solved with the assumption that L >> d >> lambda. I was curious how one would...

Homework Statement light from an atomic hydrogen lamp falls on a diffraction grating with 200 lines per centimetre. on a screen 2.5 m away, the distance between green spots of the first and second order spectra is 2.43cm while the distance between a green spot and a red spot both of the first...

Homework Statement Hi! I need help with showing how to derive this formula for the diffraction of a laser: m λ = d (sin(θm) - sin(θi)) where: d = groove spacing m = order of diffraction λ = wavelength of laser θi = angle of incidence θm = angle of diffraction Homework Equations I found this...

Hi, I've been doing Fraunhofer diffraction and I have been getting dark spots in the middle if my patterns, not predicted by the Fourier transform of the aperture. I don't think it's babinets principle and effect is stronger near the edges of the slits. Any ideas? Thanks

a wave will be diffracted as it passes by an object. in the case of light passing through a slit experiment, why isn't the probablility function of the associated photon(s) "collapsed" by its interaction with the edge of the slit? a wave will be refracted if it enters a new medium. what...

Homework Statement A single slit forms a diffraction pattern, with the first minimum at an angle of 40 from the central maximum. Monochromatic light of 410 nm wavelength is used. The same slit, illuminated by a different monochromatic light source, produces a diffraction pattern with the...

Homework Statement Hi Could someone explain to me... if a diffraction experiment that had a plane grating on it was submerged into water...why the diffracted light would produce extra angles that are wider and narrower than if the experiment had been carried in air?Homework Equations Snells...

Homework Statement You wish to study a material with a cubic crystal structure with three orthogonal sides of length a = 0.3nm. What is the longest possible wavelength of the X-ray source you could use to reveal the (211) Bragg peak of the crystal? Homework Equations nλ =...

I have no idea where to start with these questions. I am pretty sure I have to use these equations 1. theta = tan^-1(x/D) 2. wsintheta = nlambda 3. dsintheta = nlambda Which order m of in the two-slit interference pattern will give the least uncertainty in the slit spacing, d? a) m = 1 b)...

Lets say I have a double slit interference experiment set up. Now if I cover one slit what CHANGES would be observed ? I know I would see fewer bright fringes and that the intensity of the bright fringes would fall. Is there anything else ?In a different scenario I have a diffraction grating...

Homework Statement A single slit 10-4m wide(a) is illuminated by plane waves from helium-neon laser ( l = 6.328*10-7m). If the observing screen is 10m(D) away, determine the width of the central maximum(y). Homework Equations sin(alpha)=(m+0.5)*l/a tan(aplha)~sin(alpha)=y/2*D...

I'm doing some experiences with a laser about diffraction caused by an edge, and I have some question to ask. Unfortunately, I've found very few literature (almost nothing) about diffraction caused by an EDGE. Everyone explains well diffraction caused by slits; someone explains diffraction...

Homework Statement What is the difference between the pattern resulting from -2 slits, each 0.02mm wide, separated by 0.2mm AND -2 slits, each 0.02 mm wide, separated by 0.4 mm Homework Equations lambda = 2yd / (2m-1)D, m = 1,2,3, etc. D = distance from screen (where pattern is...

Say you have a square room with only one door, and the door is as the center of one side of the square. Suppose you put a stereo just outside the door. Can you hear the sound if you are standing in one of the corners of the room that's adjacent to the door? Fraunhofer diffraction predicts that...

Homework Statement In a single-slit diffraction pattern on a flat screen, the central bright fringe is 1.37 cm wide when the slit width is 3.48E-5 m. When the slit is replaced by a second slit, the wavelength of the light and the distance to the screen remaining unchanged, the central bright...

Homework Statement When a 450-nm light is incident normally on a certain double-slit system, the number of interference maxima within the central diffraction maxima is 5. When 900-nm light is incident on the same slit system, the number of interference maxima within the central diffraction...

:shy: By looking at the figures showing diffration of x-rays by crystals, it looks more like reflection.. Seems like I am studying reflection... So, where is the diffraction part??

why is it that in electron diffraction from cystals, theta i and theta r are not necessarily equal?

diffraction takes place when the wavelets are a source of more wavelets that expand in all directions, and the shape of the new wave front is curved. The wavelets of these diffracted, or bent, waves can now travel different paths and subsequently interfere with each other, producing interference...

Introduction: diffraction is an evidence that light is wave. Photo electric effect shows that light is particle. Question: What about reflection and refraction? Are they evidences of the wave nature of light or of the corpuscular theory?

Homework Statement (a) In a double-slit system, what value of d/a causes diffraction to eliminate the third bright side fringe? Homework Equations I(\theta) = I_mcos^2(\beta)(\frac{sin(\alpha)}{\alpha})^2 \beta =\frac{\pi d}{\lambda} sin \theta \alpha = \frac{\pi a}{\lambda} sin \theta...