Diffraction Definition and 1000 Threads

Homework Statement A beam of monochromatic light of wavelength 500 nm falls normally on a diffraction grating. What is the spacing between slits on the grating if a first order maximum is observed at 32o? a. 2.88 m b. 0.944 m c. 0.750 m d. 0.500 m e. 0.250 m Homework Equations...

Homework Statement A very large diffraction grating has an amplitude transmission aperture function A(x) = 1/2[1+cos(kx)]e^(-x^2/a^2) a) What is the far-field irradiance diffraction pattern when a >>1/k B) Plot the pattern c) Using the appropriate resolving criteria, find the grating's...

Hi there, My textbook says "When a beam of high energy electrons is directed at a thin solid sample of an element, the incident electrons are diffracted by the nuclei of the atoms in the foil." What does this mean exactly? Are the atoms diffracted by the gap between different nuclei? It...

http://asymmetricphotons.davehewitt.com/__oneclick_uploads/2012/03/asymm.JPG While playing with lasers in a simple home setup, I have produced asymmetrical diffraction patterns and have been unable to locate explanations in the public domain. By using a green led laser and two parallel panels...

i understand that when we shoot x-rays at a object, it will scatter in accordance to bragg's reflection law. as such we position the detector as per the picture below my question is , for the production of characteristic x-rays, does bragg's reflection law still holds? and why does...

What is the effect of change of wavelength on diffraction pattern?Does it effects intensity or fringe width?

I've searched online and on the forum but still can't find an explanation or mechanism behind why diffraction is dependent upon wavelength. For example, assume a water wave that diffracts around a small boat (smaller than the wavelength). The degree of diffraction decreases as the boat gets...

Homework Statement http://www.xtremepapers.com/CIE/International%20A%20And%20AS%20Level/9702%20-%20Physics/9702_s02_qp_2.pdf question no. 7b Homework Equations dsin∅=nλ The Attempt at a Solution I subtracted the two angles and got 26 degrees. So then I plugged...

i wonder how we can describe the degree of diffraction of waves in a single slit in a mathematical formula , with the variables , wavelength and slit width ...my attempt to it is to use the equation for double-slit interference(or plane transmission grating) , namely 'd sin theta=n lambda'...

Homework Statement A laser with monochromatic light of frequency 6.33 × 10^14 Hz is fired through a diffraction grating. If the first minimum in this diffraction pattern coincides with the position of the second order that was seen in the previous diffraction pattern, what is the width of...

Homework Statement A single slit forms a diffraction pattern with monochromatic light. The 6th minimum of the pattern occurs at an angle of 23° from the central maximum. The number of bright bands on either side of the central band is closest to: A) 16 B) 13 C) 14 D) 15 E) 17 Homework...

Hi. The grating equation says n x λ = d sinθ. Where d = 1/N (the nymber of slits per unit length.) Using the equation and solving for a grating with large number of slits gives the result that the diffraction pattern should have a greater angle of deviation from central maximum for...

I've been studying waves and diffraction has come up, I'd just like to know, why is it that diffraction is most significant when the size of a gap a wave passes through is similar to the wave length?

Homework Statement Consider a metal with an BCC crystal structure and atomic weight 92.91. When monochromatic x-radiation having a wavelength of 0.14 nm is used, the angle of diffraction (2*theta) for the (211) set of planes in this metal occurs at 41.148 ° (first-order reflection)...

Whatt happens during destructive interference of electrons. Two electrons(waves) combine and cancel each other out so no dot is produced on the screen?? Then where did the electrons go? First of all : How is a dot created on the screen? - is it because of the wave nature of electron or...

Homework Statement In an experimental setup (shown in attachment) like this for neutron diffraction, how do I find the wavelength of the neutron. It should be around 2nm. Homework Equations \lambda = \frac{h}{mv}=\frac{396}{v} The Attempt at a Solution I am having trouble with...

How do crystallographers go from a diffraction pattern to actually determining the structure of the crystal? http://pwatlas.mt.umist.ac.uk/internetmicroscope/micrographs/microscopy/decr5a-a-big.jpg

Homework Statement The number of lines per metre in a grating is 500,000, calculate grate spacing. The wavelength of light going through the grating is 600nm, what is the angle of the first order? What is the frequency of the light is it's speed is 3 x 10^8 m/s? Homework Equations The...

1. Homework Statement I'm choosing an angle for a diffraction grating such that a laser of particular wavelength λ is retroreflected (reflected back along incident path). 2. Homework Equations If you have a better way than using the equation below, feel free to explain. The book that I'm...

I'm choosing an angle for a diffraction grating such that a particular wavelength λ is retroreflected (reflected back along incident path). The book that I'm looking through treats the blazed diffraction grating as a set of N slits. This results in the equation...

Hi In the Diffraction Handbook http://gratings.newport.com/library/handbook/chapter6.asp#6.2.4 it says: A grating used in the Littrow or autocollimating configuration diffracts light of wavelength λ back along the incident light direction (Figure 6-4). In a Littrow monochromator, the...

I've been asking myself this question that is not entirely clear to me: the Bragg condition used to describe the constructive interference of waves on a crystal is based on the assumption of reflection. However, x-rays diffract on a crystal rather than reflect, so theoretically there is always...

Hi In lab classes today I worked with diffraction gratings, but there is one thing I can't quite seem to understand. If we deal with ruled diffraction gratings, then they are blazed at angle such that the first order is reflected back at the same angle as the incident angle with a specific...

How do get the d spacing from XRD data, using braggs law. I am unsure how to actually obtain the value of d. I have attached the file as a text file with the data in. Many thanks for the help.

Homework Statement How does adding a lens behind a slit alter the diffraction pattern given you know it's focal length? Homework Equations I know currently that i'd look at equations such as: y_{n} = \frac{nD\lambda}{d} Destructive and so fourth But what about the lens, does that...

hey all. i was wondering what's the diffrance between quasicrystal diffraction pattern and normal crystals (single and multiple).. where can i find some info about the diffrences? thanks , alon

Hi, I was having a flick around Google maps whilst procrastinating and came across this when I looked at some islands off the Australian coast. I'm not 100% certain that the pattern is caused by diffraction of the waves passing through the gap between Bernier and Dorre Islands, or simply...

Hello everybody, I'm having some trouble comprehending the following image. I am supposed to be able to deduce from the figure that the total difference in phase angle is (k-k')r. To begin with, I do not understand why for the diffracted wave the difference in phase angle is -k'*r while for the...

Hi guys, I can't find my notes on Fresnel diffraction and I have my Optics exam on Monday... Does anyone know how to derive F=a2/λL where L=1/z+1/z' I've googled it to death, checked here and tried in Optics 4th edition by Hecht with no luck... I'd really appreciate any help...

Homework Statement Laser light of wavelength 632.8 nm falls normally on a slit that is 0.0210 mm wide. The transmitted light is viewed on a distant screen where the intensity at the center of the central bright fringe is 8.50 W/m2. a) Find the maximum number of totally dark fringes on the...

Hi Guys, my textbook mentioned that how the equation for the minima for single slit diffraction was derived: Consider a slit of width W with 2 light rays, one emitting from the edge, one emitting from the center. Their path difference is W/2 sin T . If the path difference is 1/2 lambda, then...

Hi, this is my first post. I have a problem to solve: "Given the plane (1 1 1) of 3 lattice sc, bcc and fcc, says in which case there is diffraction" I hope that someone helps me... Thanks for helpers

Homework Statement How many interference fringes are visible in the central diffraction peak if the ratio of slit separation to slit width is 3.125? Homework Equations d*sin(θ) = m*λ for interference maxima with slit separation d, maxima are at m = 0, 1, 2, 3 ... a*sin(θ) = m*λ for...

need simulate program for fresnel biprism diffraction(urgent) Dear friends I am student learning phyisics (8th term or 4th year) this is my last term and I have optic My teacher told us that he want some programs to simulate some optice expriments like : prism - young expriment - loid...

A light passing through a lens will be focused for a converging lens. However, to look at it carefully, it'll not converge to a single point but to a certain size. The size of it and some fringes surround it is actually a diffraction phenomenon. I don't really understand that the usual...

So my book has an equation describing the wavelengths of light that are diffracted by a chiral nematic liquid crystal in terms of the refractive index (n), the pitch of the helix (p), and the angle (θ) with respect to the surface. The equation is this - λ = np√((1-cos2θ)/n2) If this isn't...

I know it is a simple question but I cannot find the answer. Why is the [001] diffraction peak not observed in XRD but [004] peak is observed. Thank you.

When the wavelength is bigger than an obstacle, then the sound waves bend around the obstacle. so why I can't imagine this at all I read this page and watched the animations of it but it doesn't tell me the answer http://www.acoustics.salford.ac.uk/feschools/waves/diffract.htm reflection of...

Homework Statement Suppose that you have a reflection diffraction grating with n=140 lines per millimeter. Light from a sodium lamp passes through the grating and is diffracted onto a distant screen. How wide does this grating need to be to allow you to resolve the two lines 589.00 and...

Homework Statement A very thin sheet of plastic (n=1.70) covers one slit of a double-slit apparatus illuminated by 630 nm light. The center point on the screen, instead of being a maximum, is dark. What is the (minimum) thickness of the plastic? Homework Equations Constructive...

I'm looking for a book that might teach me how to read diffraction patterns and infer structure. I'm also interested in the history of the technique. This is mainly so I can explain it with confidence to high school students and college freshmen as a teacher. I feel like I never really went...

Homework Statement The same diffraction grating is used with two different wavelengths of light, λA and λB. The fourth-order principal maximum of light A exactly overlaps the third-order principal maximum of light B. Find the ratio λA/λB. Homework Equations sin theta = m lambda /...

Homework Statement A zone plate is to be set up on an optical bench, where it will be used as an enlarging lens. Its innermost zone is to be 0.2250 mm in diameter and monochromatic blue-green light of wavelength 480 nm from a cadmium arc is to be used. If the magnitude of the enlargements is...

Could someone help me with the path taken by the emergent ray for blue light if it is refracted most than red light rays.the emergent ray for the red light lies on the boundary of the prism after being diffracted and forms the criticle angle(c). Is the path taken by the refracted blue light ray...

Homework Statement White light was shone vertically down on a cd tilted 5°, with adjacent tracks d = 720 nm. An observer some distance away observes a color of light. Determine that wavelength of light observed. (Refer to picture attachment) Homework Equations finding path...

Homework Statement Homework Equations n\lambda = 2dsin(\theta) The Attempt at a Solution a) solving for d I get \frac{n*\lambda}{2*sin*(\theta)} = d substituting in the first value 50.85 to solve for d, with n=1 I get d= 1.754*10^-10m How do I solve the miller indices from the inter...

This isn't a homework question per se, I'm just wondering about something in my textbook (Halliday & Resnick) that isn't clear to me: This figure shows intensity as a function of angle (0 degrees is the center) for three experiments that use single slits of different width. The one on the...

Dear All, I appreciate the efforts and support of members/admin here toward the goodness of education. I am confusing a few concepts regarding diffraction, kindly help me out. I came up with following questions, 1. Is apperture required for diffraction or any finite wave will diffract...

Homework Statement A diffraction grating has 4,200 rulings/cm. On a screen 2.00 m from the grating, it is found that for a particular order m, the maximum corresponding to two closely spaced wavelengths of sodium (589.0 nm and 589.6 nm) are separated by 1.54 mm. Determine the value of m...

I was wondering what occurs when light encounters a slit that happens to be smaller than the wavelength of light that's trying to go through it. Does it just reflect back, does part of it go through thereby making the light have a shorter wavelength that matches the slit, what actually...