Diffraction Definition and 1000 Threads

Dear everyone, I'm wondering what the diffraction limited spot is. When a laser(CW) is used to excite a fluorescent single molecule, the fluorescence from a single molecule is shown in the CCD camera. The size of fluorescence molecule is determined by Airy Disc which comes from diffraction...

I'm trying to calculate the diffraction limit/angular resolution for the Hubble Space Telescope. I know this can be found using the formula: \theta = 1.22 \frac{\lambda}{D} Where \lambda is the wavelength of the light being observed and D is the diameter of the objective lens (2.5 m on...

Hey, I'm working on a problem about the atomic form factor. I found that the atomic form factor of an fcc lattice of Buckyballs (C60 atoms) looks like f~(sin(Gr))/G multiplied bij some constants. The question is now to explain from this atomic form factor why the (2,0,0) X-ray diffraction...

Homework Statement 1. The intensities of Kalpha and Kbeta of a Cu X-ray tube have a ratio of about 10/1. It is desirable to increase the ratio to 1000/1 by using a Ni foil as a critical absorber. What should be the thickness of the Ni foil? How much attenuation in intensity has the Cu Kalpha...

Homework Statement The aperture has vertical opaque strips of width, a, separated by open spaces of width 2a. The width of the overall aperture is L = 19a. a) Write a transmission function for this aperture. b) What would the field distribution be, at a plane in the Fraunhofer zone, if the...

What are the diffraction conditions for plans in a hexagonal closed packed lattice with atoms of the same type at 000 1/3 2/3 1/2?

A conceptual problem for me anyway! In the standard texts a Huygens construction is used to explain the diffraction pattern from a single slit. However it is not used in the explanations for double (or multiple slits). What is the justification for this ... the double slit pattern should be...

Two isotropic (radiating the same intensity of EM wave in all directions) point sources S1and S2 emit light in phase at wavelength λ and at the same amplitude. The sources are separated by distance 2d=6.00λ. They lie on the axis that parallel to the x-axis, which runs along a viewing screen at...

Hello! X-ray powder diffraction can be used to determine the structure of crystal. I am given the diffraction angles (theta) for a sample and I am supposed to see if it has fcc, bcc or diamond structure. I read that if one plots sqr(sin(theta)) against ( sqr(h) +sqr(k) +sqr(l) ) where h, k, l...

Homework Statement Light of wavelength 587.5 nm illuminates a single 0.75 mm wide slit. (a) At what distance from the slit should a screen be placed if the first minimum in the diffraction pattern is to be 0.85 mm from the central maximum? (b) Calculate the width of the central maximum...

Homework Statement An aircraft causes a horizontal layer of charged particles to be formed in the atmosphere. Radio waves are relected without phase from this layer. Radio waves of frequency 8.00 x 10^2 kHz are received at a location 12 km from the transmitter. What is the minimum height of...

hello I wonder if the diffraction pattern after Laserlight going thru a grating pattern (say 10 slots) has anything to do with the Fourier transform of the grating pattern. I am not a physicist, but have some knowledge of Fourier math. I think the spatial frequencies of the grating pattern...

Homework Statement A single electron with de Broglie wavelength \lambda passes through a slit of width d = 2\lambda. The electron can then strike a flourescent screen. What will be observed on the screen? a) A diffraction pattern b) A single flash has if the electron had moved in a straight...

Homework Statement I'm just making sure I have the correct parameters for a linear graph. The experiment used a diffraction tube to verify deBroglie's hypothesis. The goal is to find the correct lattice spacings in graphite for d(10) and d(11). This might be lacking in pertinent information...

In Modern Quantum Mechanics, Sakurai say that at quantum level the gravity is no more geometrical because the schrodinger equation depend on the fraction \frac{m}{\hbar}. Can someone explain better this claim or link me some detailed paper on this argument?

Homework Statement Two loud speakers emit sound waves of the same wavelength.When a microphone is moved between them quiet places are observed 20cm apart.What is the wavelength of the sound waves? Homework Equations The Attempt at a Solution

Homework Statement green light of wavelength 5000 A is incident normally on a grating, and the 2nd order image is diffracted 32 degrees from the normal. how many lines/cm are marked on the grating A=10^-10 n= 2 degree= 32 d=? wavelength- 5000 A the answer to...

We know that to observe diffraction the width of the apertures in the grating must be of the order of the wave-length used. Would we observe diffraction if the apertures are significantly narrower than the order of wavelength used? Or what would be the difference? I think we would not observe...

Homework Statement Monochromatic light shines on the surface of a diffraction grating with 5.3x10^3 lines/cm. The first order maximum is observed at an angle of 17 (degrees). Find the wavelength. a) 420nm c) 530nm b) 520nm d) 550nm Homework...

Homework Statement A powdered sample of a simle cubic crystal with a lattice constat of 2.83 x 10^-10 m scatters X-rays of wavelength 1.54 x 10^-10 m. What is the smallest angle of scattering that will be observed from this sample? Homework Equations 2dsinθ = nλ The Attempt at a...

For diffraction patterns, the simple relation for the angle corresponding to dark fringes is sinθd = mλ/a, in which a is the width of the slit and m = {all integers excluding 0}. From this, it appears that a slit only allows certain wavelengths (a slit width corresponding to a length equal to...

How do the photons actually interact with the atoms to make them diffract. is it related to de broglies equation some how? Also with High energy electron diffraction, are the electrons being diffracted because they are attracted and repelled electrostatically from the nucleus and orbiting...

Hi I was wondering whether anyone could suggest ways of making nice diffraction patterns using a red laser. I work at a charitable school in Kazakhstan so am limited in terms of materials. Any suggestions would be appreciated. Thanks

Homework Statement Consider a plane wave (of wavelength λ) incident on a wall at an angle Φ = 30. There are two slits in the wall separated by a distance d=10λ. Each slit has width a<<λ. Rays emerging from the slits propagate to a distant screen where an interference/diffraction pattern may be...

Homework Statement Monochromatic light from a helium-neon laser(lambda=632.8nm) is incident normally on a diffraction grating containing 6000lines/cm.Find angles at which the 1storder,2nd.. Homework Equations The Attempt at a Solution here goes my solutions, given lambda=632.8 X...

Homework Statement A microwave detector is located 0.5m above the surface of a large lake far from the shore. As a star, emitting monochromatic microwave radiation of 21cm wavelength, rises slowly above the horizon, the detector indicates successive maxima and minima in the signal...

Homework Statement I have the classic slit-diffraction experiment, where light is incident on two narrow slits on a screen and is diffracted to create a pattern of maxima and minima on the far surface. It is usually assumed that the light incident on the slits is uniform. In practice, the...

In Young's double slit experiment, how come the interefernece pattern produced does not take into account single slit diffraction? Thanks

My advisor recently asked me a series of questions that made me realize I don't fully understand how the Fourier transform of, let's say series of vertical lines, produces a diffraction pattern like those seen in a TEM. To get a better understanding I re-read Hecht's short little chapter on...

In the famous two-split experiment in your freshman college class, you learn that shining a light at a wall with two narrow slits causes a diffraction pattern. Something that's always bothered me is in these ideal setups, we always assume the wall is a continuous barrier to the light. But the...

A certain crystal has a planar spacing of .25nm. What energies are necessary to observe up to three interference (diffraction) maxima for a)electrons and b)neutrons?

I have been looking for a comprehensive definition of what Electron Diffraction and Particle Diffraction and all my reference books etc. have ones which are hard to get into my head. Can anyone explain it from the point of view of a student to another student? Many Thanks, James

Homework Statement White light is spread out into its spectral components by a diffraction grating. If the grating has 2469 lines/cm, at what angle does red light of wavelength 635 nm appear in first order? Answer in units of ◦. Homework Equations sin(theta) = m(\lambda /d) The...

Diffraction Grating? [URGENT] Homework Statement Consider two monochromatic sources of light, blue light of wavelength λb = 460 nm and red light of wavelength 670 nm. The red light is shun upon a diffraction grating of density, nr = 10,000 lines per cm. A diffraction grating with what line...

Does gravitational lensing cause diffraction patterns, such as those seen by single, double, etc slit diffraction? In other words, would x-rays from object X get bent "less" than say microwaves or infrared? Would this happen if the light was passing between binary stars only, or could it...

In order to increase the diffraction efficiency of the AOM, we need to reduce the beam size of the laser. According to the manual of my AOM, it needs to have the beam size of 220um to get more than 90% diffraction efficiency. So, I decided to do so by putting a lens in front of it and...

Homework Statement Diffraction occurs for all types of waves, including sound waves. High-frequency sound from a distant source with wavelength 9.20 cm passes through a narrow slit 11.5 cm wide. A microphone is placed 35.0 cm directly in front of the center of the slit. The microphone is then...

Homework Statement The distance d from the center of the pattern to the location of the third diffraction minimum of the red laser is 4.05 centimeters. The wavelength of the red laser is 633 nanometers and the slit is 0.15 millimeters wide. How far is the screen from the slit? Homework...

a Fourier transform of an aperature results the pattern of the fraunhofer diffraction fringes at infinity of light passing that aperature. How can we understand that point physically? I tried much to think about it! but no use. Everyone, Please give your thought about this, so I can have...

Homework Statement A 550 lines/mm diffraction grating is illuminated by light of wavelength 550nm. How many bright fringes are seen on a 3.1-m-wide screen located 2.1m behind the grating? Homework Equations \DeltaY = \lambda*L/d where Y is equal to the fringe spacing... lamda is...

DIFFRACTION PROBLEMS -- please help tough problems, any help or either one is greatly appreciated (1) Consider the single-slit diffraction pattern in figure V.2, which gives the location of the central maximum, and the zeros of the diffraction. If Z=1m and lambda=6*10^-7m, using the data...

One of my prelab problems for physics 3: The Moon is about 4*10^8 m from the Earth and has a diameter of about 3.2*10^6 m. You want a radar antenna which just covers the Moon with the central spot of its diffraction pattern. If the radar wavelength is 10 cm, what is the diameter of the radar...

How can empty space act as individual point sources as in sinle slit diffraction?

Homework Statement I am trying to solve the following homework problem: 1) A laser beam of light with wavelength λ=600nm shines perpendicular to a slide that has a rectangular pattern of small holes that can be viewed as point sources. The spacing between the holes is a=40μm and b=30μm...

I have two questions here, 1. The two slits of a double slit each have a width of 0.140 mm and a distance between centers of 0.840 mm, (a) What orders are missing? (b) What is the approximate intensity of orders m=1 to m=3, relative to the zeroth-order maximum? 2. Sketch the intensity...

Problem: Diffraction of X rays has been observed when a beam strikes an extremely fine slit. What must be the width if the slit if X rays of wavelength 10A are to display a diffraction pattern with a central beam of angular width 0.1? I used Bragg's equation to obtain...

1. A neutron has a kinetic energy of 10MeV. What size object is necessary to observe neutron diffraction effects? Is there anything in nature of this size that could serve as a target to demonstrate the wave number of 10MeV neutrons? K= 10MeV or 1.602 x 10^-12J Mass of neutron = 1.675...

OK, I'm working on a homework problem and I'm a little stuck. Problem: You want to detect th efringes in he diffraction pattern produced by sunlight passing through a fine slit in the blinds covering a window. You have available a filter that blocks all wavelengths except 550nm, and you...

Hi, at my Uni we have a lab course where we first take some measurements and then write a report about the experiment. Our current experiment was about microwave diffraction. First, we measured the wave length of the microwaves, and then proceeded to measure the intensity of the scattered...

Homework Statement I have to find "sinθ" and "d" in the diffraction equation. Homework Equations The formula is n(lambda) = d(sinθ) I have the n, length, width, and hypotenuse. http://img81.imageshack.us/my.php?image=captureee1.jpg n=1, L=335 W=42.5 hyp=337.8 The Attempt at a Solution I...