Diffraction Definition and 1000 Threads

Light normally doesn't interfere with itself because it is incoherent and unpolarized, right? So how is it that incoherent, unpolarized light passes through a circular aperture and interferes with itself? How does the aperture suddenly cause the light to be able to interfere with itself? In...

Hello, could someone tell me what is the main difference between effects of diffraction and interference? For now, I think that diffraction is name for deviation of waves when they come to obstacle. And interference is phenomenon when two or more waves are in superposition in some point...

Hi, I'm having some trouble understanding the path difference between two parallel rays leaving a single slit, and was hoping you guys could help me. I'm having a hard time understand what path differences exist for each subsection of a slit and for which minimum. For example: -What is the...

Homework Statement Light with a wavelength of 475 nm produces a first order maximum 0.214 m from the central bright line for a particular diffraction apparatus. At what distance would you expect a maximum using light of 625 nm? The Attempt at a Solution I am confused. For some reason...

Hi! I am confused about the difference between the Bragg and Laue Diffraction. It seems that both arrive at the same result, but the assumptions for both are different?

Homework Statement This is the light intensity on a viewing screen behind a rectangular opening in a screen. Is the shape of the opening (1), (2), or (3)? Homework Equations w=(2λL)/a where w is the width of the central maximum, L is the distance to the viewing screen, and a is...

Homework Statement Electrons are accelerated to an energy of 2.40 keV and then passed through a thin graphite film. The distance between the carbon atoms is 1.42 * 10^-10 m. Homework Equations b) Describe the diffraction pattern on a screen 5.00 cm from the graphite film. We're looking for...

Homework Statement This is the interference pattern on a viewing screen behind two slits. (image of 7 bright fringes with black fringes between every pair of bright fringes) How would the pattern change if the two slits were replaced by 20 slits having the same spacing d between...

Homework Statement See figure attached for problem statement as well as my attempt Homework Equations The Attempt at a Solution I don't know where to go from here. Can someone help me get started?

So for 2 point sources (or 2 slits) the formula for finding the lines of maxima and minima for waves is n(lambda)=dsin(theta) and when n is an integer you would expect to find a maxima. However, I don't understand why this formula also applies to diffraction gratings since there are way more...

This isn't exactly a homework question but just a few conceptual questions I'm confused about. First off on the topic of diffraction I notice many textbooks and other resources say that diffraction is more evident when the width of a slit is close to the wavelength of the wave. However, they...

Homework Statement I am required to calculate the width of a single slit. I have known distance, L, between the observation screen and the slit, and photo images were taken of the resulting waveform. However, the wavelength is unknown, therefore making many of the equations I'm attempting to...

I watched the Feynman lectures on light . And when he talks about a photon bouncing off a mirror, and that it usually bounces off at the angle it hits, But then he says I'm going to do a dirty trick and paint black lines in the mirror. Like if he paints enough lines the light will diffract...

Hello everyone, It's said that the first Brilloin zone is the k-space where electrons are not diffracted. Electrons with k-vectors on the surface of BZ are diffracted. How can we understand in terms of electron particules the behavior of electrons associated waves when these waves...

Homework Statement Identify the following as an example of Refraction, Diffraction, or Interference 1) Rainbow pattern on a compact disk 2) The floating blotches in our eyes 3) Rainbow pattern on a beetle's back 4) The dark bands seen a a window screen Homework Equations...

I was idly musing (as you do) and I was thinking of Fermat's principle which says that light takes the 'shortest route'. That, however, must refer to the classical situation. Take the simplest diffraction situation of two slits - or forming the really complex diffraction pattern from a large...

Homework Statement I did the single slit light diffraction lab. The diode laser we used was 630-680 nm. It produced an image very much like the one on this page: http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/fraungeo.html#c1 How does having multiple wavelengths in the laser change...

an someone explain to me the symbol "m" in dsin\theta=m\lambda, where m is the order of diffraction (or whatever it's called). I am using a fluorospectrometer at which the sin\theta is always equal to 1. This instrument can fix the excitation \lambda. The main point is that scattering of the 1st...

Homework Statement Light with wavelengths of 520 nm and 630nm passes through a diffraction grating that contains 6000 lines/cm. 1) Calcualte the angles for the first and second order maxima that would appear on the screen Homework Equations sin(Theta)m = m(Lamda)/d The Attempt at a...

Homework Statement How to make difference between the light that has traveled through a prism and the light that has traveled through a diffraction grating when only place that is visible to the viewer is the place where the white light lands? The Attempt at a Solution Sorry, but i...

Hello all, I have a basic question with the theta-2theta technique in XRD. Here it is: If I have a single crystal material and I perform the above mentioned characterization. Should I get one diffraction peak associated to the orientation of the bulk crystal or should I get many peaks...

Homework Statement Light emitted by Element X passes through a diffraction grating having 1200 lines/mm. The diffraction pattern is observed on a screen 75.0 cm behind the grating. Bright fringes are seen on the screen at distances of 56.2 cm, 65.9 cm, and 93.5 cm from the central maximum. No...

Homework Statement Electrons pass through a 10-6m wide slit with a speed of 1.5 x 106m/s. How wide is the electron diffraction pattern on a detector 1 m behind the slit. Homework Equations \lambda=h/mv (matter waves) asin\theta=m\lambda (path length difference for constructive...

I've done plenty of problems over the course of my degree that involve waves passing through slits of widths comparable to their wavelengths, and spreading out. As far as I'm aware though, I haven't been told what is actually going on there, just that it does happen. I know that we can...

Hi. I cannot understand what the order of diffraction means. Could anybody give me some link with animation or detailed explanation? I do not understand why it should be integer to create constructive interference?

Homework Statement Consider the following, A collimated light source impinges on a plane diffraction grating and diffracts via the well known diffraction equation. The diffracted light is then collimated by a 1 metre focal length lens (good quality one). It is experimentally verified that the...

When light goes through a narrow single slit it diffracts. And you can explain this with the uncertainty principle or the wave-like nature of light. But if a photon can only be in one medium at a time then how does it know its going through a slit , How is it interacting with the edges of the...

Short question, but I can't figure it out - when we have a diffraction on any obstacle, which is construction of spherical Huygens waves, why the situation presents as it is shown on the first picture and not like on the second picture, what could actually be expected, as we consider spherical...

Homework Statement [PLAIN]http://img714.imageshack.us/img714/8205/65617184.jpg Homework Equations I = I_{0} [\frac{sin[\pi a(sin\theta)/\lambda]}{\pi a(sin\theta)/\lambda}]^{2} The Attempt at a Solution Here is my attempt: I = I_{0} [\frac{sin[\pi (50)(sin\1)/632]}{\pi...

Consider one slit white light diffraction which produces rainbow fringe - black fringe - white fringe-black fringe-rainbow fringe. That is, continuous spectrum (or...two continuous spectrums). My question is, instead of white light, project monochromatic red light. What happens then leaving all...

Does anyone have an idea on how to build a homemade Diffraction Grating . If its too hard I could buy one there not that much. It would be cooler to build one tho.

When waves diffract through one slit why does it form a series of maxima and minima when there is no interference?...our teacher won't tell us and its really annoying me...and i have no idea why it should. please help! ~sorry if this is in he wrong place

Homework Statement You will need to know the spacing d between grooves on the diffraction grating used in the lab. If the this diffraction grating has 13400 grooves per inch, how many grooves per meter does it have? Homework Equations 1 inch = 39.37 meters The Attempt at a...

Homework Statement From the intensities of the first-order peaks in the spectrum of a diffraction grating with monochromatic (633 nm) light shining on it, estimate the aperture size. Also known: grating constant (20 nm), distance from grating to screen (25 cm), positions of first-order peaks...

Homework Statement Light of wavelength 490 nm is incident on a narrow slit. The diffraction pattern is viewed on a screen 3.6 m from the slit. The distance on the screen between the central maximum and the third minimum is 2 cm. What is the width of the slit? Homework Equations The...

Diffraction is obviously a limiting constraint on high-precision imaging instruments. But is it possible, given a known aperture shape, to remove the diffraction caused by that aperture? At this point, I know that the diffraction pattern of an aperture or slide film brought to rear focus is...

Homework Statement Single-slit diffraction can be observed with any type of electromagnetic wave (not just light). Suppose you want to make a diffraction slit whose width is seven times larger than the wavelength for the following cases. How wide would the slit be? (a) A radio wave for...

I don't know why my intuition tells me that generally if a monochromatic wave goes toward an aperture smaller than its wavelength (or half its wavelength maybe), the wave can't go through the aperture. Is it true? I don't think so now... I see no reason why it would be true. And we couldn't...

A lecturer is demonstrating two-slit interference with sound waves. Two speakers are used, 1.9 m apart. The sound frequency is 1220Hz and the speed of sound is 343 m/s. Students sit facing the speakers in a row of sear 5.4 m away. Along the row of students, what is the spacing between the...

So I understand that thin hair or wire can make a diffraction pattern, but why would the diffraction pattern be horizontal when the hair is vertical?

Monochromatic light with a wavelength of 419 nm passes through a single slit and falls on a screen 88 cm away. If the distance of the first-order dark band is 0.29 cm from the center of the pattern, what is the width of the slit? My knowns are as follows: L= 88 cm (distance from slit to...

Homework Statement http://b.imagehost.org/0607/Question_7.png Homework Equations [PLAIN][PLAIN]http://d.imagehost.org/0813/Untitled_6.jpg The Attempt at a Solution I was able to get question b, which ends up being 73pm, but as for questions a and c, I was unable to come up with...

Homework Statement Light of wavelength 460nm falls on two slits spaced .3 mm apart. What is the required distance from the slit to a screen if the spacing between the first and second dark fringes is to be 4mm?Homework Equations dsin(theta)=(m+1/2)lambda where d = .3mm y=4mm lambda = 460nm...

Homework Statement What is the diffraction-limited object size (at 25 cm) imposed by the numerical aperture of the eye (if the eye is a diffraction-limited optic)? Use 4mm for the iris diameter and 550 nm for the wavelength. Homework Equations Rayleigh criterion states: for angular...

In the book of the Dr. Ronald Askeland the problem about x-ray diffraction use the next planes indices to calculate the interplanar distance, but I don't understand why to use such planes indices? Are these planes all of planes in a cubic structure? (111) (200) (211)...

Homework Statement Show that the angular locations of the first to fourth secondary maximas are \alpha = a sin \Theta/\Lambda = 1.43030 2.45902 3.47089 4.46641 respectively. a is the slit width = 0.00016m \Lambda wavelength of laser 650nm Homework Equations I(\Theta) = I0...

How many dark fringes will be produced n either side of the central maximum if light (its wavelength is 651 nm ) is incident on a single slit that is 5.47x10^-6 m wide? sin (theta) = m.wavelength/w

I have read that the wavelength must be according to the size of aperture to get diffraction phenomena. Considering normal incidence on the aperture, please explain why the wavelength should be of the order of aperture, as wavelength is perpendicular to the diameter of aperture, & any wave can...

I wonder is there any application for diffraction and diffraction grating in daily life except for lab purposes?:bugeye:

Hi Please can someone explain in a simple way what the Diffraction plane & image plane are Thanks